Next:   [Contents][Index]

GNU Gnulib

This manual is for GNU Gnulib (updated 2026-07-04 14:52:25), which is a library of common routines intended to be shared at the source level.

Copyright © 2004–2026 Free Software Foundation, Inc.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled “GNU Free Documentation License”.

Table of Contents

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

1 Brief Overview

Gnulib is a source code library that provides basic functionality to programs and libraries. Many software packages make use of Gnulib to avoid reinventing the portability wheel.

Resources:

Next: , Up: Brief Overview   [Contents][Index]

1.1 Gnulib Basics

While portability across operating systems is not one of GNU’s primary goals, it has helped introduce many people to the GNU system, and is worthwhile when it can be achieved at a low cost. This collection helps lower that cost.

Gnulib is intended to be the canonical source for most of the important “portability” and/or common files for GNU projects. These are files intended to be shared at the source level; Gnulib is not a typical library meant to be installed and linked against. Thus, unlike most projects, Gnulib does not normally generate a source tarball distribution; instead, developers grab modules directly from the source repository.

The easiest, and recommended, way to do this is to use the gnulib-tool script. Since there is no installation procedure for Gnulib, gnulib-tool needs to be run directly in the directory that contains the Gnulib source code. You can do this either by specifying the absolute filename of gnulib-tool, or by using a symbolic link from a place inside your PATH to the gnulib-tool file of your preferred Gnulib checkout. For example: 

$ ln -s $HOME/gnu/src/gnulib.git/gnulib-tool $HOME/bin/gnulib-tool

Next: , Previous: , Up: Brief Overview   [Contents][Index]

1.2 Git Checkout

Gnulib is available for anonymous checkout. In any Bourne-shell the following should work: 

$ git clone https://git.savannah.gnu.org/git/gnulib.git

For a read-write checkout you need to have a login on ‘savannah.gnu.org’ and be a member of the Gnulib project at https://savannah.gnu.org/projects/gnulib. Then, instead of the URL https://git.savannah.gnu.org/git/gnulib.git, use the URL ‘ssh://user@git.savannah.gnu.org/srv/git/gnulib’ where user is your login name on savannah.gnu.org.

git resources:

Overview:

https://en.wikipedia.org/wiki/Git_(software)

Homepage:

https://git-scm.com/

When you use git annotate or git blame with Gnulib, it’s recommended that you use the -w option, in order to ignore massive whitespace changes that happened in 2009.

Next: , Previous: , Up: Brief Overview   [Contents][Index]

1.3 Keeping Up-to-date

The best way to work with Gnulib is to check it out of git. To synchronize, you can use git pull.

Subscribing to the mailing list will help you to plan when to update your local copy of Gnulib (which you use to maintain your software) from git. You can review the archives, subscribe, etc., via https://lists.gnu.org/mailman/listinfo/bug-gnulib.

Sometimes, using an updated version of Gnulib will require you to use newer versions of GNU Automake or Autoconf. You may find it helpful to join the autotools-announce mailing list to be advised of such changes.

Next: , Previous: , Up: Brief Overview   [Contents][Index]

1.4 Contributing to Gnulib

All software here is copyrighted by the Free Software Foundation—you need to have filled out an assignment form for a project that uses the module for that contribution to be accepted here.

If you have a piece of code that you would like to contribute, please email .

Generally we are looking for files that fulfill at least one of the following requirements:

  • If your .c and .h files define functions that are broken or missing on some other system, we should be able to include it.
  • If your functions remove arbitrary limits from existing functions (either under the same name, or as a slightly different name), we should be able to include it.

If your functions define completely new but rarely used functionality, you should probably consider packaging it as a separate library.

Next: , Up: Contributing to Gnulib   [Contents][Index]

1.4.1 Gnulib licensing

Gnulib contains code both under GPL and LGPL. Because several packages that use Gnulib are GPL, the files state they are licensed under GPL. However, to support LGPL projects as well, you may use some of the files under LGPL. The “License:” information in the files under modules/ clarifies the real license that applies to the module source.

Keep in mind that if you submit patches to files in Gnulib, you should license them under a compatible license, which means that sometimes the contribution will have to be LGPL, if the original file is available under LGPL via a “License: LGPL” information in the projects’ modules/ file.

Next: , Previous: , Up: Contributing to Gnulib   [Contents][Index]

1.4.2 Indent with spaces not TABs

We use space-only indentation in nearly all files. This includes all *.h, *.c, *.y files, except for the regex module. Makefile and ChangeLog files are excluded, since TAB characters are part of their format.

In order to tell your editor to produce space-only indentation, you can use these instructions.

  • For Emacs: Add these lines to your Emacs initialization file ($HOME/.emacs or similar): 
    ;; In Gnulib, indent with spaces everywhere (not TABs).
;; Exceptions: Makefile and ChangeLog modes.
(add-hook 'find-file-hook '(lambda ()
  (if (and buffer-file-name
           (string-match "/gnulib\\>" (buffer-file-name))
           (not (string-equal mode-name "Change Log"))
           (not (string-equal mode-name "Makefile")))
      (setq indent-tabs-mode nil))))
  • For vi (vim): Add these lines to your $HOME/.vimrc file: 
    " Don't use tabs for indentation. Spaces are nicer to work with.
set expandtab

    For Makefile and ChangeLog files, compensate for this by adding this to your $HOME/.vim/after/indent/make.vim file, and similarly for your $HOME/.vim/after/indent/changelog.vim file: 

    " Use tabs for indentation, regardless of the global setting.
set noexpandtab
  • For Eclipse: In the “Window|Preferences” dialog (or “Eclipse|Preferences” dialog on Mac OS),
    1. Under “General|Editors|Text Editors”, select the “Insert spaces for tabs” checkbox.
    2. Under “C/C++|Code Style”, select a code style profile that has the “Indentation|Tab policy” combobox set to “Spaces only”, such as the “GNU [built-in]” policy.

    If you use the GNU indent program, pass it the option --no-tabs.

Previous: , Up: Contributing to Gnulib   [Contents][Index]

1.4.3 How to add a new module

  • Add the header files and source files to lib/.
  • If the module needs configure-time checks, write an Autoconf macro for it in m4/module.m4. See m4/README for details.
  • Write a module description modules/module, based on modules/TEMPLATE.
  • If the module contributes a section to the end-user documentation, put this documentation in doc/module.texi and add it to the “Files” section of modules/module. Most modules don’t do this; they have only documentation for the programmer (= Gnulib user). Such documentation usually goes into the lib/ source files. It may also go into doc/; but don’t add it to the module description in this case.
  • Add the module to the list in MODULES.html.sh.

You can test that a module builds correctly with: 

$ ./gnulib-tool --create-testdir --dir=/tmp/testdir module1 ... moduleN
$ cd /tmp/testdir
$ ./configure && make

Other things:

  • Check the license and copyright year of headers.
  • Check that the source code follows the GNU coding standards; see https://www.gnu.org/prep/standards.
  • Add source files to config/srclist* if they are identical to upstream and should be upgraded in Gnulib whenever the upstream source changes.
  • Include header files in source files to verify the function prototypes.
  • Make sure a replacement function doesn’t cause warnings or clashes on systems that have the function.
  • Autoconf functions can use ‘gl_*’ prefix. The ‘AC_*’ prefix is for autoconf internal functions.
  • Build files only if they are needed on a platform. Look at the alloca and fnmatch modules for how to achieve this. If for some reason you cannot do this, and you have a .c file that leads to an empty .o file on some platforms (through some big #if around all the code), then ensure that the compilation unit is not empty after preprocessing. One way to do this is to #include <stddef.h> or <stdio.h> before the big #if.

Next: , Previous: , Up: Brief Overview   [Contents][Index]

1.5 Portability guidelines

Gnulib code is intended to be portable to a wide variety of platforms, not just GNU platforms. Gnulib typically attempts to support a platform as long as it is still supported by its provider, even if the platform is not the latest version. See Target Platforms.

Many Gnulib modules exist so that applications need not worry about undesirable variability in implementations. For example, an application that uses the malloc module need not worry about malloc (0) returning a null pointer on some Standard C platforms; and glob users need not worry about glob silently omitting symbolic links to nonexistent files on some platforms that do not conform to POSIX.

Gnulib code is intended to port without problem to new hosts, e.g., hosts conforming to recent C and POSIX standards. Hence Gnulib code should avoid using constructs that these newer standards no longer require, without first testing for the presence of these constructs. For example, because C11 made variable length arrays optional, Gnulib code should avoid them unless it first uses the vararrays module to check whether they are supported.

The following subsections discuss some exceptions and caveats to the general Gnulib portability guidelines.

Next: , Up: Portability guidelines   [Contents][Index]

1.5.1 C language versions

Currently Gnulib assumes at least a freestanding C99 compiler, possibly operating with a C library that predates C99; with time this assumption will likely be strengthened to later versions of the C standard. Old platforms currently supported include AIX 7.3 and Solaris 10, though these platforms are rarely tested. Gnulib itself is so old that it contains many fixes for obsolete platforms, fixes that may be removed in the future.

Because of the freestanding C99 assumption, Gnulib code can include <float.h>, <limits.h>, <stdarg.h>, <stddef.h>, and <stdint.h> unconditionally; <stdbool.h> is also in the C99 freestanding list but is obsolescent as of C23. Gnulib code can also assume the existence of <ctype.h>, <errno.h>, <fcntl.h>, <locale.h>, <signal.h>, <stdio.h>, <stdlib.h>, <string.h>, and <time.h>. Similarly, many modules include <sys/types.h> even though it’s not in the C standard; that’s OK since <sys/types.h> has been around since Seventh Edition Unix (1979).

Even if the include files exist, they may not conform to the C standard. However, GCC has a fixincludes script that attempts to fix most conformance problems. Gnulib currently assumes include files largely conform to C99 or better. People still using ancient hosts should use fixincludes or fix their include files manually.

Even if the include files conform, the library itself may not. For example, strtod and mktime have some bugs on some platforms. You can work around some of these problems by requiring the relevant modules, e.g., the Gnulib mktime module supplies a working and conforming mktime.

Next: , Previous: , Up: Portability guidelines   [Contents][Index]

1.5.2 C99 features assumed by Gnulib

Although the C99 standard specifies many features, Gnulib code is conservative about using them, partly because Gnulib predates the widespread adoption of C99, and partly because many C99 features are not well-supported in practice. C99 features that are reasonably portable nowadays include:

  • A declaration after a statement, or as the first clause in a for statement.
  • long long int.
  • <stdbool.h>, although Gnulib code no longer uses it directly, preferring plain bool via the bool module instead. See stdbool.h.
  • <stdint.h>, assuming the stdint-h module is used. See stdint.h.
  • Compound literals and designated initializers.
  • Empty arguments in macro calls.
  • Variadic macros.
    Note: The handling of __VA_ARGS__ in MSVC differs from the one in ISO C 99, see https://stackoverflow.com/questions/5134523/. But usually this matters only for macros that decompose __VA_ARGS__.
  • static inline functions.
  • __func__, assuming the func module is used. See func.
  • The restrict qualifier, assuming AC_REQUIRE([AC_C_RESTRICT]) is used. This qualifier is sometimes implemented via a macro, so C++ code that uses Gnulib should avoid using restrict as an identifier.
  • Flexible array members (however, see the flexmember module).

Next: , Previous: , Up: Portability guidelines   [Contents][Index]

1.5.3 C99 features avoided by Gnulib

Gnulib avoids some features even though they are standardized by C99, as they have portability problems in practice. Here is a partial list of avoided C99 features. Many other C99 features are portable only if their corresponding modules are used; Gnulib code that uses such a feature should require the corresponding module.

  • Variable length arrays (VLAs) or variably modified types, without checking whether __STDC_NO_VLA__ is defined. See the vararrays and vla modules.
  • Block-scope variable length arrays, without checking whether either GNULIB_NO_VLA or __STDC_NO_VLA__ is defined. This lets you define GNULIB_NO_VLA to pacify GCC when using its -Wvla-larger-than warnings option, and to avoid large stack usage that may have security implications. GNULIB_NO_VLA does not affect Gnulib’s other uses of VLAs and variably modified types, such as array declarations in function prototype scope.
  • Converting to pointers via integer types other than intptr_t or uintptr_t. Although the C standard says that values of these integer types, if they exist, should be convertible to and from intmax_t and uintmax_t without loss of information, on CHERI platforms such conversions result in integers that, if converted back to a pointer, cannot be dereferenced.
  • extern inline functions, without checking whether they are supported. See Extern inline functions.
  • Type-generic math functions.
  • Universal character names in source code.
  • <iso646.h>, since GNU programs need not worry about deficient source-code encodings.
  • Comments beginning with ‘//’. This is mostly for style reasons.

Previous: , Up: Portability guidelines   [Contents][Index]

1.5.4 Other portability assumptions made by Gnulib

Gnulib code makes the following assumptions that go beyond what C and POSIX require:

  • Standard internal types like ptrdiff_t and size_t are no wider than long. The GNU coding standards allow code to make this assumption, POSIX requires implementations to support at least one programming environment where this is true, and such environments are recommended for Gnulib-using applications. When it is easy to port to non-POSIX platforms like MinGW where these types are wider than long, new Gnulib code should do so, e.g., by using ptrdiff_t instead of long. However, it is not always that easy, and no effort has been made to check that all Gnulib modules work on MinGW-like environments.
  • int and unsigned int are at least 32 bits wide. POSIX and the GNU coding standards both require this.
  • Signed integer arithmetic is two’s complement.

    Although some Gnulib modules contain explicit support for ones’ complement and signed magnitude integer representations, which are allowed by C17 and earlier, these modules are the exception rather than the rule. All practical Gnulib targets use two’s complement, which is required by C23.

  • When an out-of-range integer value is copied to a signed integer, low-order bits are copied and high-order bits are silently discarded.

    Although the C standard says the that the resulting signed value is implementation-defined or an implementation-defined signal is raised, all known platforms simply copy the low-order bits, just as the C standard requires when copying to an unsigned integer.

    This assumption is merely about copying data, not about arithmetic. Previously, Gnulib code sometimes also assumed that signed integer arithmetic wraps around, but modern compiler optimizations sometimes do not guarantee this, and Gnulib code with this assumption is now considered to be questionable. See Integer Properties.

  • There are no “holes” in integer values: all the bits of an integer contribute to its value in the usual way. In particular, an unsigned type and its signed counterpart have the same number of bits when you count the latter’s sign bit. (As an exception, Gnulib code is portable to CHERI platforms even though this assumption is false for CHERI.)
  • Objects with all bits zero are treated as zero or as null pointers. For example, memset (A, 0, sizeof A) initializes an array A of pointers to null pointers.
  • The types intptr_t and uintptr_t exist, and pointers can be converted to and from these types without loss of information.
  • Addresses and sizes behave as if objects reside in a flat address space. In particular:
    • If two nonoverlapping objects have sizes S and T represented as ptrdiff_t or size_t values, then S + T cannot overflow.
    • A pointer P points within an object O if and only if (char *) &O <= (char *) P && (char *) P < (char *) (&O + 1).
    • Arithmetic on a valid pointer is equivalent to the same arithmetic on the pointer converted to uintptr_t, except that offsets are multiplied by the size of the pointed-to objects. For example, if P + I is a valid expression involving a pointer P and an integer I, then (uintptr_t) (P + I) == (uintptr_t) ((uintptr_t) P + I * sizeof *P). Similar arithmetic can be done with intptr_t, although more care must be taken in case of integer overflow or negative integers.
    • A pointer P has alignment A if and only if (uintptr_t) P % A is zero, and similarly for intptr_t. Although C23 says that portable code should instead test whether memalignment (P) % A is zero, memalignment is missing in many non-C23 systems, is not specified to work portably on pointers to atomic or volatile memory, and is likely a bit slower than the cast.
    • If an existing object has size S, and if T is sufficiently small (e.g., 8 KiB), then S + T cannot overflow. Overflow in this case would mean that the rest of your program fits into T bytes, which can’t happen in realistic flat-address-space hosts.
    • Adding zero to a null pointer does not change the pointer. For example, 0 + (char *) NULL == (char *) NULL. Similarly, subtracting zero does not change a null pointer, and subtracting two null pointers results in zero. C23 was the first C standard to require this behavior; see “Allow zero length operations on null pointers”, WG14 N3322 (2024-08-28); which was adopted retroactively for C23.

Some system platforms violate these assumptions and are therefore not Gnulib porting targets. See Unsupported Platforms.

Next: , Previous: , Up: Brief Overview   [Contents][Index]

1.6 High Quality

We develop and maintain a testsuite for Gnulib. The goal is to have a 100% firm interface so that maintainers can feel free to update to the code in git at any time and know that their application will not break. This means that before any change can be committed to the repository, a test suite program must be produced that exposes the bug for regression testing.

Next: , Up: High Quality   [Contents][Index]

1.6.1 Stable Branches

In Gnulib, we don’t use topic branches for experimental work. Therefore, occasionally a broken commit may be pushed in Gnulib. It does not happen often, but it does happen.

To compensate for this, Gnulib offers “stable branches”. These are branches of the Gnulib code that are maintained over some longer period (a year, for example) and include

  • bug fixes,
  • portability enhancements (to existing as well as to new platforms),
  • updates to config.guess and config.sub.

Not included in the stable branches are:

  • new features, such as new modules,
  • optimizations,
  • refactorings,
  • complex or risky changes in general,
  • updates to texinfo.tex,
  • documentation updates.

So far, we have nine stable branches:

stable-202601

A stable branch that starts at the beginning of January 2026.

stable-202507

A stable branch that starts at the beginning of July 2025.

stable-202501

A stable branch that starts at the beginning of January 2025. It is no longer updated.

stable-202407

A stable branch that starts at the beginning of July 2024. It is no longer updated.

stable-202401

A stable branch that starts at the beginning of January 2024. It is no longer updated.

stable-202307

A stable branch that starts at the beginning of July 2023. It is no longer updated.

stable-202301

A stable branch that starts at the beginning of January 2023. It is no longer updated.

stable-202207

A stable branch that starts at the beginning of July 2022. It is no longer updated.

stable-202201

A stable branch that starts at the beginning of January 2022. It is no longer updated.

The two use-cases of stable branches are thus:

  • You want to protect yourself from occasional breakage in Gnulib.
  • When making a bug-fix release of your code, you can incorporate bug fixes in Gnulib, by pulling in the newest commits from the same stable branch that you were already using for the previous release.

Previous: , Up: High Quality   [Contents][Index]

1.6.2 Writing reliable code

When compiling and testing Gnulib and Gnulib-using programs, certain compiler options can help improve reliability. First of all, make it a habit to use ‘-Wall’ in all compilation commands. Beyond that, the manywarnings module enables several forms of static checking in GCC and related compilers (see manywarnings).

For dynamic checking, you can run configure with CFLAGS options appropriate for your compiler. For example: 

./configure \
 CPPFLAGS='-Wall'\
 CFLAGS='-g3 -O2'\
' -D_FORTIFY_SOURCE=3'\
' -D_GLIBCXX_ASSERTIONS'\
' -fsanitize=undefined'\
' -fsanitize-trap=all'

Here:

  • -D_FORTIFY_SOURCE=3 and -D_GLIBCXX_ASSERTIONS enable extra security hardening checks in the GNU C library and GNU C++ library, respectively.
  • -fsanitize=undefined enables GCC’s undefined behavior sanitizer (ubsan), and
  • -fsanitize-trap=all causes ubsan to abort the program (through an “illegal instruction” signal). This measure stops exploit attempts and also allows you to debug the issue.

Without the -fsanitize-trap=all option, -fsanitize=undefined causes messages to be printed, and execution continues after an undefined behavior situation. The message printing causes GCC-like compilers to arrange for the program to dynamically link to libraries it might not otherwise need. With GCC, instead of -fsanitize-trap=all you can use the -static-libubsan option to arrange for two of the extra libraries (libstdc++ and libubsan) to be linked statically rather than dynamically, though this typically bloats the executable and the remaining extra libraries are still linked dynamically.

It is also good to occasionally run the programs under valgrind (see Running self-tests under valgrind).

GCC’s -fhardened option can also be used, but with caution because it is designed for production more than testing, and therefore enables -ftrivial-auto-var-init=zero which can mask program errors.

Previous: , Up: Brief Overview   [Contents][Index]

1.7 Join the GNU Project

GNU Gnulib is part of the GNU Operating System, developed by the GNU Project.

If you are the author of an awesome program and want to join us in writing Free (libre) Software, please consider making it an official GNU program and become a GNU Maintainer. Instructions on how to do this are here. We are looking forward to hacking with you!

Don’t have a program to contribute? Look at all the other ways to help.

And to learn more about Free (libre) Software in general, please read and share this page.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

2 Philosophy

Gnulib’s design and development philosophy is organized around steady, collaborative, and open development of reusable modules that are suitable for a reasonably wide variety of platforms.

Next: , Up: Philosophy   [Contents][Index]

2.1 Benefits of using Gnulib

Gnulib is useful to enhance various aspects of a package:

  • Portability: With Gnulib, a package maintainer can program against the POSIX and GNU libc APIs and nevertheless expect good portability to platforms that don’t implement POSIX.
  • Maintainability: When a package uses modules from Gnulib instead of code written specifically for that package, the maintainer has less code to maintain.
  • Security: Gnulib provides functions that are immune against vulnerabilities that plague the uses of the corresponding commonplace functions. For example, asprintf, canonicalize_file_name are not affected by buffer sizing problems that affect sprintf, realpath. openat does not have the race conditions that open has. Etc.
  • Reliability: Gnulib provides functions that combine a call to a system function with a check of the result. Examples are xalloc, xprintf, xstrtod, xgetcwd.
  • Structure: Gnulib offers a way to structure code into modules, typically one include file, one source code file, and one autoconf macro for each functionality. Modularity helps maintainability.

Next: , Previous: , Up: Philosophy   [Contents][Index]

2.2 Library vs. Reusable Code

Classical libraries are installed as binary object code. Gnulib is different: It is used as a source code library. Each package that uses Gnulib thus ships with part of the Gnulib source code. The used portion of Gnulib is tailored to the package: A build tool, called gnulib-tool, is provided that copies a tailored subset of Gnulib into the package.

Up: Library vs. Reusable Code   [Contents][Index]

2.2.1 Comparison with other source code libraries

Many programming languages nowadays have

  • an ecosystem of reusable source code packages, available through a central site,
  • together with a tool that downloads dependencies from this central site.

Here is a table of such source code libraries.

LanguageCentral siteDownload tool
Pythonpypi.org‘pip’
Javamvnrepository.com‘maven’, ‘gradle’
C#nuget.org‘nuget’
JavaScript, TypeScriptnpmjs.com‘npm’, ‘yarn’
Common Lispquicklisp.org‘ql:quickload’
Emacs Lispelpa.gnu.org‘M-x package-install’
Rustcrates.io‘cargo’
Gopkg.go.dev‘go mod’
Rubyrubygems.org‘gem’
Lualuarocks.org‘luarocks’
OCamlocaml.org/packages‘opam’
Dcode.dlang.org‘dub’
Perlcpan.org‘cpan’
PHPpackagist.org‘composer’
Rcran.r-project.org‘R CMD INSTALL’

Most of them are vulnerable to supply chain attacks. These are cyber-attacks to the central site (library) or to one of the packages in the library, with the goal of attacking the packages that use that specific package as a (direct or indirect) dependency.

Examples of such supply chain attacks:

  • A disenchanted package maintainer may replace the code of their package with something that does not work any more.
  • An attacker may plant a backdoor in a package.
  • An attacker may register packages whose names only slightly differ from well-known and heavily used packages (“typo-squatting”).

While some mitigations exist, they are often cumbersome to put in place. For example, a developer could set up a partial mirror of the library, where adding a package to the mirror is a manual operation, together with a configuration or modification of the tool that redirects download or installation requests to the mirror.

Gnulib is not vulnerable to such attacks, because all of its code is managed in a single repository, with a limited set of committers and with established code review practices.

Next: , Previous: , Up: Philosophy   [Contents][Index]

2.3 Portability and Application Code

One of the goals of Gnulib is to make portable programming easy, on the basis of the standards relevant for GNU (and Unix). The objective behind that is to avoid a fragmentation of the user community into disjoint user communities according to the operating system, and instead allow synergies between users on different operating systems.

Another goal of Gnulib is to provide application code that can be shared between several applications. Some people wonder: "What? glibc doesn’t have a function to copy a file?" Indeed, the scope of a system’s libc is to implement the relevant standards (ISO C, POSIX) and to provide access functions to the kernel’s system calls, and little more.

There is no clear borderline between both areas.

For example, Gnulib has a facility for generating the name of backup files. While this task is entirely at the application level—no standard specifies an API for it—the naïve code has some portability problems because on some platforms the length of file name components is limited to 30 characters or so. Gnulib handles that.

Similarly, Gnulib has a facility for executing a command in a subprocess. It is at the same time a portability enhancement (it works on GNU, Unix, and Windows, compared to the classical fork/exec idiom which is not portable to Windows), as well as an application aid: it takes care of redirecting stdin and/or stdout if desired, and emits an error message if the subprocess failed.

Next: , Previous: , Up: Philosophy   [Contents][Index]

2.4 Target Platforms

Gnulib supports a number of platforms that we call the “reasonable portability targets”. This class consists of widespread operating systems, for three years after their last availability, or—for proprietary operating systems—as long as the vendor provides commercial support for it. Already existing Gnulib code for older operating systems is usually left in place for longer than these three years. So it comes that programs that use Gnulib run pretty well also on these older operating systems.

Some operating systems are not very widespread, but are Free Software and are actively developed. Such platforms are also supported by Gnulib, if that OS’s developers community keeps in touch with the Gnulib developers, by providing bug reports, analyses, or patches. For such platforms, Gnulib supports only the versions of the last year or the last few months, depending on the maturity of said OS project, the number of its users, and how often these users upgrade.

Niche operating systems are generally unsupported by Gnulib, unless some of their developers or users contribute support to Gnulib.

The degree of support Gnulib guarantees for a platform depends on the amount of testing it gets from volunteers. Platforms on which Gnulib is frequently tested are the best supported. Then come platforms with occasional testing, then platforms which are rarely tested. Usually, we fix bugs when they are reported. Except that some rarely tested platforms are also low priority; bug fixes for these platforms can take longer.

Next: , Up: Target Platforms   [Contents][Index]

2.4.1 Supported Platforms

As of 2024, the list of supported platforms is the following:

  • glibc systems. With glibc 2.19 or newer, they are frequently tested. About the kernels:
    • glibc on Linux is frequently tested.
    • glibc on kFreeBSD is rarely tested.
    • musl libc on Linux is occasionally tested.
  • macOS. In versions 12.5, it’s occasionally tested. In version 10.5, it’s rarely tested.
  • FreeBSD 14.0 or newer is occasionally tested.
  • OpenBSD 7.0 or newer is occasionally tested.
  • NetBSD 10.0 or newer is occasionally tested.
  • CheriBSD 25.03 or newer is occasionally tested.
  • AIX 7.1 and 7.3 are occasionally tested.
  • Solaris 10 and 11.4 are occasionally tested. Solaris 9 is rarely tested and low priority.
  • Android is occasionally tested, through the Termux app on Android 11.
  • Cygwin 2.9 and 3.4 are occasionally tested. Cygwin 1.7.x no longer tested.
  • Native Windows:
    • mingw is occasionally tested. Only the latest version of mingw is tested; older versions are not supported.
    • MSVC 14 (Microsoft Visual Studio 2015 14.0) is occasionally tested. Only “release” builds (compiler option ‘-MD’) are supported, not “debug” builds (compiler option ‘-MDd’).

    Note that some modules are currently unsupported on native Windows: mgetgroups, getugroups, idcache, userspec, openpty, login_tty, forkpty, pt_chown, grantpt, pty-h, savewd, mkancesdirs, mkdir-p, euidaccess, faccessat. The versions of Windows that are supported are Windows 10 and newer.

  • GNU Hurd 0.9 is rarely tested.
  • Minix 3.3.0 is no longer tested.
  • Haiku is no longer tested.
  • uClibc on Linux is no longer tested.
  • QNX is no longer tested.

Next: , Previous: , Up: Target Platforms   [Contents][Index]

2.4.2 Formerly Supported Platforms

The following platforms were supported in the past, but are no longer supported:

  • glibc versions 2.1.x and older.
  • Mac OS X 10.4 and older.
  • AIX 6 and older.
  • IBM XL C/C++ 13.1 and older.
  • HP-UX 11.31.
  • IRIX 6.5 and older.
  • OSF/1 5.1.
  • Solaris 8 and older.
  • Interix.
  • BeOS.

Gnulib supports these operating systems only in an unvirtualized environment. When you run an OS inside a virtual machine, you have to be aware that the virtual machine can bring in bugs of its own. For example, floating-point operations on Solaris can behave slightly differently in QEMU than on real hardware. And Haiku’s bash program misbehaves in VirtualBox 3, whereas it behaves fine in VirtualBox 4.

Similarly, running native Windows binaries on GNU/Linux under WINE is rarely tested and low priority: WINE has a set of behaviours and bugs that is slightly different from native Windows.

Previous: , Up: Target Platforms   [Contents][Index]

2.4.3 Unsupported Platforms

Some platforms with C compilers are not supported by Gnulib because the platforms violate Gnulib’s C portability assumptions. See Other portability assumptions made by Gnulib.

These assumptions are not required by the C or POSIX standards but hold on almost all practical porting targets. If you need to port Gnulib code to a platform where these assumptions are not true, we would appreciate hearing of any fixes. We need fixes that do not increase runtime overhead on standard hosts and that are relatively easy to maintain.

These platforms are listed below to illustrate problems that Gnulib and Gnulib-using code would have if it were intended to be portable to all practical POSIX or C platforms.

  • In Clang 19 and earlier, the -fsanitize=undefined option causes the program to crash if it adds zero to a null pointer – behavior that is undefined in strict C17 and earlier, but which yields a null pointer in C23 and later and on all practical porting targets, and which the Gnulib portability guidelines allow.

    If you use Clang 19 or earlier with -fsanitize=undefined, you can work around the problem by also using ‘-fno-sanitize=pointer-overflow’, although this may also disable some unrelated and useful pointer checks. Perhaps someday the Clang developers will fix the infelicity.

  • The IBM i’s pointers are 128 bits wide and it lacks the two types intptr_t and uintptr_t, which are optional in the C and POSIX standards. However, these two types are required for the XSI extension to POSIX, and many Gnulib modules use them. To work around this compatibility problem, Gnulib-using applications can be run on the IBM i’s PASE emulation environment. The IBM i’s architecture descends from the System/38 (1978).
  • The Unisys ClearPath Dorado’s machine word is 36 bits. Its signed integers use a ones’-complement representation that conforms to C17 and earlier but not to C23 and later. On these machines, CHAR_BIT == 9 and INT_MIN == -INT_MAX. By default UINT_MAX is 2^{36} - 2, which does not conform to the C requirement that it be one less than a power of two. Although compiler options can raise UINT_MAX to be 2^{36} - 1, this can break system code that uses -0 as a flag value. This platform’s architecture descends from the UNIVAC 1103 (1953).
  • The Unisys ClearPath Libra’s machine word is 48 bits with a 4-bit tag and a 4-bit data extension. Its unsigned int uses the low-order 39 bits of the word, and int uses the low-order 40 bits of the word with a signed-magnitude representation that conforms to C17 and earlier but not to C23 and later. On these machines, INT_MAX == UINT_MAX, INT_MIN == -INT_MAX, and sizeof (int) == 6. This platform’s architecture descends from the Burroughs B5000 (1961).

The following platforms are not supported by Gnulib. The cost of supporting them would exceed the benefit because they are rarely used, or poorly documented, or have been supplanted by other platforms, or diverge too much from POSIX, or some combination of these and other factors. Please don’t bother sending us patches for them.

  • Windows 95/98/ME.
  • DJGPP and EMX (the 32-bit operating systems running in DOS).
  • MSDOS (the 16-bit operating system).
  • Windows Mobile, Symbian OS, iOS.

Next: , Previous: , Up: Philosophy   [Contents][Index]

2.5 Modules

Gnulib is divided into modules. Every module implements a single facility. Modules can depend on other modules.

A module consists of a number of files and a module description. The files are copied by gnulib-tool into the package that will use it, usually verbatim, without changes. Source code files (.h, .c files) reside in the lib/ subdirectory. Autoconf macro files reside in the m4/ subdirectory. Build scripts reside in the build-aux/ subdirectory.

The module description contains the list of files; gnulib-tool copies these files. It contains the module’s dependencies; gnulib-tool installs them as well. It also contains the autoconf macro invocation (usually a single line or nothing at all); gnulib-tool ensures this is invoked from the package’s configure.ac file. And also a Makefile.am snippet; gnulib-tool collects these into a Makefile.am for the tailored Gnulib part. The module description and include file specification are for documentation purposes; they are combined into MODULES.html.

The module system serves two purposes:

  1. It ensures consistency of the used autoconf macros and Makefile.am rules with the source code. For example, source code which uses the getopt_long function—this is a common way to implement parsing of command line options in a way that complies with the GNU standards—needs the source code (lib/getopt.c and others), the autoconf macro which detects whether the system’s libc already has this function (in m4/getopt.m4), and a few Makefile.am lines that create the substitute getopt.h if not. These three pieces belong together. They cannot be used without each other. The module description and gnulib-tool ensure that they are copied altogether into the destination package.
  2. It allows for scalability. It is well-known since the inception of the MODULA-2 language around 1978 that dissection into modules with dependencies allows for building large sets of code in a maintainable way. The maintainability comes from the facts that:
    • Every module has a single purpose; you don’t worry about other parts of the program while creating, reading or modifying the code of a module.
    • The code you have to read in order to understand a module is limited to the source of the module and the .h files of the modules listed as dependencies. It is for this reason also that we recommend to put the comments describing the functions exported by a module into its .h file.

    In other words, the module is the elementary unit of code in Gnulib, comparable to a class in object-oriented languages like Java or C#.

The module system is the basis of gnulib-tool. When gnulib-tool copies a part of Gnulib into a package, it first compiles a module list, starting with the requested modules and adding all the dependencies, and then collects the files, configure.ac snippets and Makefile.am snippets.

Next: , Previous: , Up: Philosophy   [Contents][Index]

2.6 Various Kinds of Modules

There are modules of various kinds in Gnulib. For a complete list of the modules, see in MODULES.html.

2.6.1 Support for ISO C or POSIX functions.

When a function is not implemented by a system, the Gnulib module provides an implementation under the same name. Examples are the ‘snprintf’ and ‘readlink’ modules.

Similarly, when a function is not correctly implemented by a system, Gnulib provides a replacement. For functions, we use the pattern 

#if !HAVE_WORKING_FOO
# define foo rpl_foo
#endif

and implement the foo function under the name rpl_foo. This renaming is needed to avoid conflicts at compile time (in case the system header files declare foo) and at link/run time (because the code making use of foo could end up residing in a shared library, and the executable program using this library could be defining foo itself).

For header files, such as stdint.h, we provide the substitute only if the system doesn’t provide a correct one. The template of this replacement is distributed in a slightly different name, with ‘.in’ inserted before the ‘.h’ extension, so that on systems which do provide a correct header file the system’s one is used.

The modules in this category are supported in C++ mode as well. This means, while the autoconfiguration uses the C compiler, the resulting header files and function substitutes can be used with a matching C++ compiler as well.

2.6.2 Enhancements of ISO C or POSIX functions

These are sometimes POSIX functions with GNU extensions also found in glibc—examples: ‘getopt’, ‘fnmatch’—and often new APIs—for example, for all functions that allocate memory in one way or the other, we have variants which also include the error checking against the out-of-memory condition.

2.6.3 Portable general use facilities

Examples are a module for copying a file—the portability problems relate to the copying of the file’s modification time, access rights, and extended attributes—or a module for extracting the tail component of a file name—here the portability to native Windows requires a different API than the classical POSIX basename function.

2.6.4 Reusable application code

Examples are an error reporting function, a module that allows output of numbers with K/M/G suffixes, or cryptographic facilities.

2.6.5 Object oriented classes

Examples are data structures like ‘list’, or abstract output stream classes that work around the fact that an application cannot implement an stdio FILE with its logic. Here, while staying in C, we use implementation techniques like tables of function pointers, known from the C++ language or from the Linux kernel.

2.6.6 Interfaces to external libraries

Examples are the ‘iconv’ module, which interfaces to the iconv facility, regardless whether it is contained in libc or in an external libiconv. Or the ‘readline’ module, which interfaces to the GNU readline library.

2.6.7 Build / maintenance infrastructure

An example is the ‘maintainer-makefile’ module, which provides extra Makefile tags for maintaining a package.

Next: , Previous: , Up: Philosophy   [Contents][Index]

2.7 Collaborative Development

Gnulib is maintained collaboratively. The mailing list is <bug-gnulib at gnu dot org>. Be warned that some people on the list may be very active at some times and unresponsive at other times.

Every module has one or more maintainers. While issues are discussed collaboratively on the list, the maintainer of a module nevertheless has a veto right regarding changes in his module.

All patches should be posted to the list, regardless whether they are proposed patches or whether they are committed immediately by the maintainer of the particular module. The purpose is not only to inform the other users of the module, but mainly to allow peer review. It is not uncommon that several people contribute comments or spot bugs after a patch was proposed.

Conversely, if you are using Gnulib, and a patch is posted that affects one of the modules that your package uses, you have an interest in proofreading the patch.

Next: , Previous: , Up: Philosophy   [Contents][Index]

2.9 Steady Development

Gnulib modules are continually adapted, to match new practices, to be consistent with newly added modules, or simply as a response to build failure reports.

If you are willing to report an occasional regression, we recommend to use the newest version from git always, except in periods of major changes. Most Gnulib users do this.

Previous: , Up: Philosophy   [Contents][Index]

2.10 Openness

Gnulib is open in the sense that we gladly accept contributions if they are generally useful, well engineered, and if the contributors have signed the obligatory papers with the FSF.

The module system is open in the sense that a package using Gnulib can

  1. locally patch or override files in Gnulib,
  2. locally add modules that are treated like Gnulib modules by gnulib-tool.

This is achieved by the ‘--local-dir’ option of gnulib-tool (see Extending Gnulib).

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

3 Invoking gnulib-tool

The gnulib-tool command is the recommended way to import Gnulib modules. It is possible to borrow Gnulib modules in a package without using gnulib-tool, relying only on the meta-information stored in the modules/* files, but with a growing number of modules this becomes tedious. gnulib-tool simplifies the management of source files, Makefile.ams and configure.ac in packages incorporating Gnulib modules.

gnulib-tool is not installed in a standard directory that is contained in the PATH variable. It needs to be run directly in the directory that contains the Gnulib source code. You can do this either by specifying the absolute filename of gnulib-tool, or you can also use a symbolic link from a place inside your PATH to the gnulib-tool file of your preferred and most up-to-date Gnulib checkout, like this: 

$ ln -s $HOME/gnu/src/gnulib.git/gnulib-tool $HOME/bin/gnulib-tool

Run ‘gnulib-tool --help’ for information. To get familiar with gnulib-tool without affecting your sources, you can also try some commands with the option ‘--dry-run’; then gnulib-tool will only report which actions it would perform in a real run without changing anything.

Next: , Up: Invoking gnulib-tool   [Contents][Index]

3.1 Finding modules

There are four ways of finding the names of Gnulib modules that you can use in your package:

Next: , Previous: , Up: Invoking gnulib-tool   [Contents][Index]

3.2 Initial import

Gnulib assumes that your project uses Autoconf. When using Gnulib, you will need to have Autoconf among your build tools.

Gnulib also assumes that your project’s configure.ac contains the line 

AC_CONFIG_HEADERS([config.h])

The config.h file gets generated with platform dependent C macro definitions, and the source files include it (see Changing your sources for use with Gnulib).

Unless you use gnulib-tool’s --gnu-make option, Gnulib also assumes that your project uses Automake at least in a subdirectory of your project. While the use of Automake in your project’s top level directory is an easy way to fulfil the Makefile conventions of the GNU coding standards, Gnulib does not require it.

Invoking ‘gnulib-tool --import’ will copy source files, create a Makefile.am to build them, generate a file gnulib-comp.m4 with Autoconf M4 macro declarations used by configure.ac, and generate a file gnulib-cache.m4 containing the cached specification of how Gnulib is used.

Our example will be a library that uses Autoconf, Automake and Libtool. It calls strdup, and you wish to use gnulib to make the package portable to C99 and C11 (which don’t have strdup). 

~/src/libfoo$ gnulib-tool --import strdup
Module list with included dependencies:
  absolute-header
  extensions
  strdup
  string
File list:
  lib/dummy.c
  lib/strdup.c
  lib/string.in.h
  m4/absolute-header.m4
  m4/extensions.m4
  m4/gnulib-common.m4
  m4/strdup.m4
  m4/string_h.m4
Creating directory ./lib
Creating directory ./m4
Copying file lib/dummy.c
Copying file lib/strdup.c
Copying file lib/string.in.h
Copying file m4/absolute-header.m4
Copying file m4/extensions.m4
Copying file m4/gnulib-common.m4
Copying file m4/gnulib-tool.m4
Copying file m4/strdup.m4
Copying file m4/string_h.m4
Creating lib/Makefile.am
Creating m4/gnulib-cache.m4
Creating m4/gnulib-comp.m4
Finished.

You may need to add #include directives for the following .h files.
  #include <string.h>

Don't forget to
  - add "lib/Makefile" to AC_CONFIG_FILES in ./configure.ac,
  - mention "lib" in SUBDIRS in Makefile.am,
  - mention "-I m4" in ACLOCAL_AMFLAGS in Makefile.am,
    or add an AC_CONFIG_MACRO_DIRS([m4]) invocation in ./configure.ac,
  - invoke gl_EARLY in ./configure.ac, right after AC_PROG_CC,
  - invoke gl_INIT in ./configure.ac.
~/src/libfoo$

By default, the source code is copied into lib/ and the M4 macros in m4/. You can override these paths by using --source-base=DIRECTORY and --m4-base=DIRECTORY. Some modules also provide other files necessary for building. These files are copied into the directory specified by ‘AC_CONFIG_AUX_DIR’ in configure.ac or by the --aux-dir=DIRECTORY option. If neither is specified, the current directory is assumed.

gnulib-tool can make symbolic links instead of copying the source files. The option to specify for this is ‘--symlink’, or ‘-s’ for short. This can be useful to save a few kilobytes of disk space. But it is likely to introduce bugs when gnulib is updated; it is more reliable to use ‘gnulib-tool --update’ (see below) to update to newer versions of gnulib. Furthermore it requires extra effort to create self-contained tarballs, and it may disturb some mechanism the maintainer applies to the sources. For these reasons, this option is generally discouraged.

gnulib-tool will overwrite any preexisting files, in particular Makefile.am. It is also possible to separate the generated Makefile.am content (for building the gnulib library) into a separate file, say gnulib.mk, that can be included by your handwritten Makefile.am, but this is a more advanced use of gnulib-tool.

Consequently, it is a good idea to choose directories that are not already used by your projects, to separate gnulib imported files from your own files. This approach is also useful if you want to avoid conflicts between other tools (e.g., gettextize that also copy M4 files into your package. Simon Josefsson successfully uses a source base of gl/, and a M4 base of gl/m4/, in several packages.

After the ‘--import’ option on the command line comes the list of Gnulib modules that you want to incorporate in your package. The names of the modules coincide with the filenames in Gnulib’s modules/ directory.

Some Gnulib modules depend on other Gnulib modules. gnulib-tool will automatically add the needed modules as well; you need not list them explicitly. gnulib-tool will also memorize which dependent modules it has added, so that when someday a dependency is dropped, the implicitly added module is dropped as well (unless you have explicitly requested that module).

If you want to cut a dependency, i.e., not add a module although one of your requested modules depends on it, you may use the option ‘--avoid=module’ to do so. Multiple uses of this option are possible. Of course, you will then need to implement the same interface as the removed module.

A few manual steps are required to finish the initial import. gnulib-tool printed a summary of these steps.

First, you must ensure Autoconf can find the macro definitions in gnulib-comp.m4. Use the ACLOCAL_AMFLAGS specifier in your top-level Makefile.am file, as in: 

ACLOCAL_AMFLAGS = -I m4

Alternatively, add an AC_CONFIG_MACRO_DIRS invocation in your configure.ac file, as in: 

AC_CONFIG_MACRO_DIRS([m4])

You are now ready to call the M4 macros in gnulib-comp.m4 from configure.ac. The macro gl_EARLY must be called as soon as possible after verifying that the C compiler is working. Typically, this is immediately after AC_PROG_CC, as in: 

...
AC_PROG_CC
gl_EARLY
...

The core part of the gnulib checks are done by the macro gl_INIT. Place it further down in the file, typically where you normally check for header files or functions. It must come after other checks which may affect the compiler invocation, such as AC_MINIX. For example: 

...
# For gnulib.
gl_INIT
...

gl_INIT will in turn call the macros related with the gnulib functions, be it specific gnulib macros, like gl_FUNC_ALLOCA or Autoconf or Automake macros like AC_FUNC_ALLOCA or AM_FUNC_GETLINE. So there is no need to call those macros yourself when you use the corresponding gnulib modules.

You must also make sure that the gnulib library is built. Add the Makefile in the gnulib source base directory to AC_CONFIG_FILES, as in: 

AC_CONFIG_FILES(... lib/Makefile ...)

You must also make sure that make will recurse into the gnulib directory. To achieve this, add the gnulib source base directory to a SUBDIRS Makefile.am statement, as in: 

SUBDIRS = lib

or if you, more likely, already have a few entries in SUBDIRS, you can add something like: 

SUBDIRS += lib

Finally, you have to add compiler and linker flags in the appropriate source directories, so that you can make use of the gnulib library. Since some modules (‘getopt’, for example) may copy files into the build directory, top_builddir/lib is needed as well as top_srcdir/lib. For example: 

...
AM_CPPFLAGS = -I$(top_builddir)/lib -I$(top_srcdir)/lib
...
LDADD = lib/libgnu.a
...

Don’t forget to #include the various header files. In this example, you would need to make sure that ‘#include <string.h>’ is evaluated when compiling all source code files, that want to make use of strdup.

In the usual case where Autoconf is creating a config.h file, you should include config.h first, before any other include file. That way, for example, if config.h defines ‘restrict’ to be the empty string on a non-C99 host, or a macro like ‘_FILE_OFFSET_BITS’ that affects the layout of data structures, the definition is consistent for all include files. Also, on some platforms macros like ‘_FILE_OFFSET_BITS’ and ‘_GNU_SOURCE’ may be ineffective, or may have only a limited effect, if defined after the first system header file is included.

Finally, note that you cannot use AC_LIBOBJ or AC_REPLACE_FUNCS in your configure.ac and expect the resulting object files to be automatically added to lib/libgnu.a. This is because your AC_LIBOBJ and AC_REPLACE_FUNCS invocations from configure.ac augment a variable @LIBOBJS@ (and/or @LTLIBOBJS@ if using Libtool), whereas lib/libgnu.a is built from the contents of a different variable, usually @gl_LIBOBJS@ (or @gl_LTLIBOBJS@ if using Libtool).

Next: , Previous: , Up: Invoking gnulib-tool   [Contents][Index]

3.3 Modified imports

You can at any moment decide to use Gnulib differently than the last time.

There are two ways to change how Gnulib is used. Which one you’ll use, depends on where you keep track of options and module names that you pass to gnulib-tool.

  • If you store the options and module names in a file under your own control, such as autogen.sh, bootstrap, bootstrap.conf, or similar, simply invoke gnulib-tool again, with modified options and more or fewer module names.
  • gnulib-tool remembers which modules were used last time. If you want to rely on gnulib-tool’s own memory of the last used options and module names, you can use the commands gnulib-tool --add-import and gnulib-tool --remove-import.

    So, if you only want to use more Gnulib modules, simply invoke gnulib-tool --add-import new-modules. The list of modules that you pass after ‘--add-import’ is added to the previous list of modules.

    Similarly, if you want to use fewer Gnulib modules, simply invoke gnulib-tool --remove-import unneeded-modules. The list of modules that you pass after ‘--remove-import’ is removed from the previous list of modules. Note that if a module is then still needed as dependency of other modules, it will be used nevertheless. If you want to really not use a module any more, regardless of whether other modules may need it, you need to use the ‘--avoid’ option.

    For other changes, such as different choices of ‘--lib’, ‘--source-base’ or ‘--aux-dir’, the normal way is to modify manually the file gnulib-cache.m4 in the M4 macros directory, then launch ‘gnulib-tool --add-import’.

    The only change for which this doesn’t work is a change of the ‘--m4-base’ directory. Because, when you pass a different value of ‘--m4-base’, gnulib-tool will not find the previous gnulib-cache.m4 file any more. A possible solution is to manually copy the gnulib-cache.m4 into the new M4 macro directory.

    In the gnulib-cache.m4 file, the macros have the following meaning:

    gl_LOCAL_DIR

    The argument is a colon separated list of local directories where gnulib-tool will search before looking at gnulib’s directory. Corresponds to the ‘--local-dir’ command line argument.

    gl_MODULES

    The argument is a space separated list of the requested modules, not including dependencies.

    gl_WITH_OBSOLETE

    The presence of this macro corresponds to the ‘--with-obsolete’ command line argument. It takes no arguments.

    gl_WITH_CXX_TESTS

    The presence of this macro corresponds to the ‘--with-c++-tests’ command line argument and to the absence of the ‘--without-c++-tests’ command line argument. It takes no arguments.

    gl_WITH_LONGRUNNING_TESTS

    The presence of this macro corresponds to the ‘--with-longrunning-tests’ command line argument and to the absence of the ‘--without-longrunning-tests’ command line argument. It takes no arguments.

    gl_WITH_PRIVILEGED_TESTS

    The presence of this macro corresponds to the ‘--with-longrunning-tests’ command line argument and to the absence of the ‘--without-longrunning-tests’ command line argument. It takes no arguments.

    gl_WITH_UNPORTABLE_TESTS

    The presence of this macro corresponds to the ‘--with-unportable-tests’ command line argument and to the absence of the ‘--without-unportable-tests’ command line argument. It takes no arguments.

    gl_WITH_ALL_TESTS

    The presence of this macro corresponds to the ‘--with-all-tests’ command line argument. It takes no arguments.

    gl_AVOID

    The argument is a space separated list of modules that should not be used, even if they occur as dependencies. Corresponds to the ‘--avoid’ command line argument.

    gl_SOURCE_BASE

    The argument is the relative file name of the directory containing the gnulib source files (mostly *.c and *.h files). Corresponds to the ‘--source-base’ command line argument.

    gl_M4_BASE

    The argument is the relative file name of the directory containing the gnulib M4 macros (*.m4 files). Corresponds to the ‘--m4-base’ command line argument.

    gl_PO_BASE

    The argument is the relative file name of the directory containing *.po files. Corresponds to the ‘--po-base’ command line argument.

    gl_DOC_BASE

    The argument is the relative file name of the directory containing documentation files. Corresponds to the ‘--doc-base’ command line argument.

    gl_TESTS_BASE

    The argument is the relative file name of the directory containing the gnulib unit test files. Corresponds to the ‘--tests-base’ command line argument.

    gl_WITH_TESTS

    The presence of this macro corresponds to the ‘--with-tests’ command line argument. It takes no arguments.

    gl_LIB

    The argument is the name of the library to be created. Corresponds to the ‘--lib’ command line argument.

    gl_LGPL

    The presence of this macro without arguments corresponds to the ‘--lgpl’ command line argument. The presence of this macro with an argument (whose value must be 2 or 3) corresponds to the ‘--lgpl=arg’ command line argument.

    gl_GPL

    The presence of this macro with an argument (whose value must be 2 or 3) corresponds to the ‘--gpl=arg’ command line argument.

    gl_MAKEFILE_NAME

    The argument is the name of the makefile in the source-base and tests-base directories. Corresponds to the ‘--makefile-name’ command line argument.

    gl_TESTS_MAKEFILE_NAME

    The argument is the name of the makefile in the tests-base directory. Corresponds to the ‘--tests-makefile-name’ command line argument.

    gl_AUTOMAKE_SUBDIR

    The presence of this macro corresponds to the ‘--automake-subdir’ command line argument. It takes no arguments.

    gl_CONDITIONAL_DEPENDENCIES

    The presence of this macro corresponds to the ‘--conditional-dependencies’ command line argument and to the absence of the ‘--no-conditional-dependencies’ command line argument. It takes no arguments.

    gl_LIBTOOL

    The presence of this macro corresponds to the ‘--libtool’ command line argument and to the absence of the ‘--no-libtool’ command line argument. It takes no arguments.

    gl_MACRO_PREFIX

    The argument is the prefix to use for macros in the gnulib-comp.m4 file. Corresponds to the ‘--macro-prefix’ command line argument.

    gl_PO_DOMAIN

    The argument is the prefix of the i18n domain, typically matching the package name. Corresponds to the ‘--po-domain’ command line argument.

    gl_WITNESS_C_MACRO

    The argument is the C macro that is defined when the sources in this directory are compiled or used. Corresponds to the ‘--witness-c-macro’ command line argument.

    gl_VC_FILES

    The argument to this macro is true or false. The former corresponds to the ‘--vc-files’ command line argument and the latter corresponds to the ‘--no-vc-files’ command line argument.

Next: , Previous: , Up: Invoking gnulib-tool   [Contents][Index]

3.4 Simple update

When you want to update to a more recent version of Gnulib, without changing the list of modules or other parameters, a simple call does it: 

$ gnulib-tool --add-import

This will create, update or remove files, as needed.

Note: From time to time, changes are made in Gnulib that are not backward compatible. When updating to a more recent Gnulib, you should consult Gnulib’s NEWS file to check whether the incompatible changes affect your project.

Next: , Previous: , Up: Invoking gnulib-tool   [Contents][Index]

3.5 Changing your sources for use with Gnulib

When you use Gnulib, you need to make some small changes to your source code base.

Next: , Up: Changing your sources for use with Gnulib   [Contents][Index]

3.5.1 -I options

Gnulib contains some header file overrides. This means that when building on systems with deficient header files in /usr/include/, it may create files named string.h, stdlib.h, stdint.h or similar in the build directory. In the other source directories of your package you will usually pass ‘-I’ options to the compiler, so that these Gnulib substitutes are visible and take precedence over the files in /usr/include/.

Next: , Previous: , Up: Changing your sources for use with Gnulib   [Contents][Index]

3.5.2 Include <config.h>

These Gnulib substitute header files rely on <config.h> being already included. Furthermore <config.h> must be the first include in every compilation unit. This means that to all your source files and likely also to all your tests source files you need to add an ‘#include <config.h>’ at the top. Which source files are affected? Exactly those whose compilation includes a ‘-I’ option that refers to the Gnulib library directory.

This is annoying, but inevitable: On many systems, <config.h> is used to set system dependent flags (such as _GNU_SOURCE on GNU systems), and these flags have no effect after any system header file has been included.

Previous: , Up: Changing your sources for use with Gnulib   [Contents][Index]

3.5.3 Style of #include statements

When including including specific header files, you need to use the ‘#include <...>’ syntax, not the ‘#include "..."’ syntax. This is true for the following POSIX or ISO C standardized header files:

  • arpa/inet.h
  • assert.h
  • ctype.h
  • dirent.h
  • endian.h
  • errno.h
  • fcntl.h
  • fenv.h
  • float.h
  • fnmatch.h
  • glob.h
  • iconv.h
  • inttypes.h
  • langinfo.h
  • limits.h
  • locale.h
  • math.h
  • monetary.h
  • net/if.h
  • netdb.h
  • netinet/in.h
  • poll.h
  • pthread.h
  • sched.h
  • search.h
  • signal.h
  • spawn.h
  • stdalign.h
  • stdarg.h
  • stdcountof.h
  • stddef.h
  • stdint.h
  • stdio.h
  • stdlib.h
  • string.h
  • strings.h
  • sys/msg.h
  • sys/resource.h
  • sys/select.h
  • sys/sem.h
  • sys/shm.h
  • sys/socket.h
  • sys/stat.h
  • sys/time.h
  • sys/times.h
  • sys/types.h
  • sys/uio.h
  • sys/un.h
  • sys/utsname.h
  • sys/wait.h
  • termios.h
  • threads.h
  • time.h
  • uchar.h
  • unistd.h
  • utime.h
  • wchar.h
  • wctype.h

as well as for the following header files that exist in the GNU C library but are not standardized:

  • alloca.h
  • byteswap.h
  • error.h
  • getopt.h
  • malloc.h
  • mntent.h
  • omp.h
  • pty.h
  • selinux/selinux.h
  • sys/file.h
  • sys/ioctl.h
  • sys/random.h
  • sysexits.h
  • utmp.h

The reason for this requirement is that for these header files, the Gnulib override uses #include_next to include the system-provided header of the same name, and #include_next may not work right with the ‘#include "..."’ syntax.

Next: , Previous: , Up: Invoking gnulib-tool   [Contents][Index]

Gnulib contains a wealth of portability workarounds for ISO C and POSIX functions. They are listed in detail in the chapter ISO C and POSIX Function Substitutes. If you want to know which function substitutes are recommended for your package, you can search your source code for ISO C and POSIX functions that it uses and read the corresponding sections of said documentation chapter. But this is a tedious task. Here is an alternative approach that makes this task easier.

  1. Add the Gnulib module ‘posixcheck’ to the Gnulib imports of your package, as described earlier in this chapter.
  2. Do a make distclean if you previously built in the top-level directory. Then regenerate the Autotools-generated parts of the package.
  3. On a glibc system, build your package. Pay attention to the compiler warnings. Warnings are generated for uses of ISO C and POSIX functions that have portability problems or other important pitfalls and for which you have not yet imported the corresponding Gnulib module. If you get, say, a warning “warning: call to ’close’ declared with attribute warning: close does not portably work on sockets - use gnulib module close for portability”, put ‘close’ on your list of modules to import.
  4. Add the modules you noted to the Gnulib imports of your package.
  5. Optionally, you can do the same steps again, and make sure that there are no warnings left except those that you want to intentionally ignore.
  6. Finally, remove the Gnulib module ‘posixcheck’ from the Gnulib imports, and run make distclean.

Next: , Previous: , Up: Invoking gnulib-tool   [Contents][Index]

3.8 Modifying the build rules of a Gnulib import directory

In some cases, you may want to set additional compiler options for use within the Gnulib import directory. For example, the ‘relocatable’ module operates better if you define the C macros ENABLE_COSTLY_RELOCATABLE and INSTALLDIR during its compilation.

There are two ways to do so: Use of the gnulib-tool option --makefile-name, and a kitchen-sink module.

With the gnulib-tool option --makefile-name, you are telling gnulib-tool to generate an includable Makefile.am portion, rather than a self-contained Makefile.am. For example, when you use --makefile-name=Makefile.gnulib, gnulib-tool will generate Makefile.gnulib, and you will provide a hand-written Makefile.am that includes Makefile.gnulib through a line such as 

include Makefile.gnulib

Before this include, you need to initialize a set of Makefile.am variables.

For the directory into which gnulib-tool copies the gnulib source files, the set of variables to initialize is:

  • AUTOMAKE_OPTIONS
  • SUBDIRS
  • noinst_HEADERS
  • noinst_LIBRARIES
  • noinst_LTLIBRARIES
  • pkgdata_DATA (only with Automake ≥ 1.11.4)
  • EXTRA_DIST
  • BUILT_SOURCES
  • SUFFIXES
  • MOSTLYCLEANFILES
  • MOSTLYCLEANDIRS
  • CLEANFILES
  • DISTCLEANFILES
  • MAINTAINERCLEANFILES
  • AM_CPPFLAGS
  • AM_CFLAGS

AUTOMAKE_OPTIONS should be initialized as described in Changing Automake’s Behavior in GNU Automake. The other variables can be initialized to empty. However, you will most likely want to initialize some of them with non-empty values, in order to achieve the desired customization.

For the directory into which gnulib-tool copies the gnulib unit test files (when option ‘--with-tests’ is used), the set of variables to initialize is:

  • AM_CFLAGS
  • AM_CXXFLAGS (when this directory contains some C++ code)

The other approach, the kitchen-sink module, is more advanced. See chapter Extending Gnulib.

Next: , Previous: , Up: Invoking gnulib-tool   [Contents][Index]

3.9 Building directly from the top-level directory

By default, the Gnulib import directory will contain a generated Makefile.am file. After configuring, this produces a generated Makefile in this directory. As a consequence, the build from the top-level directory will use a recursive make invocation for this directory.

Some people prefer a build system where the Makefile in the top-level directory directly builds the artifacts in the subdirectories, without an intermediate make invocation. This is called “non-recursive make” and is supported by Automake. For more details, see https://autotools.io/automake/nonrecursive.html.

Gnulib supports this flavour of build system too. To use it, pass two options to gnulib-tool: ‘--makefile-name’ and ‘--automake-subdir’.

With the gnulib-tool option ‘--makefile-name’, you are telling gnulib-tool to generate an includable Makefile.am portion in the Gnulib import directory, rather than a self-contained Makefile.am. For example, when you use ‘--makefile-name=Makefile.gnulib’, gnulib-tool will generate Makefile.gnulib.

With the option ‘--automake-subdir’, you are telling gnulib-tool that you will include the generated file from the Makefile.am in the top-level directory, rather than from a Makefile.am in the same directory. For example, the top-level Makefile.am might contain this directive: 

include lib/Makefile.gnulib

The option ‘--automake-subdir’ is also supported in combination with ‘--with-tests’ (see Bundling the unit tests of the Gnulib modules). Note that in this case, however, the generated unit tests directory will contains a Makefile.am and thus use a recursive make invocation. This is not a problem, since the built artifacts of your package have no dependencies towards the Gnulib unit tests, nor vice versa.

Next: , Previous: , Up: Invoking gnulib-tool   [Contents][Index]

3.10 Using Gnulib for both a library and a program

Your project might build both a library and some accompanying programs in the same source tree. In that case you might want to use different modules for the library than for the programs. Typically the programs might want to make use of getopt-posix or version-etc, while the library wants to stay clear of these modules for technical or licensing reasons.

Let’s assume that your project contains a lib directory where the source of the library resides and a src directory for the sources of the programs as follows. 

.
|-- configure.ac
|-- lib
|   |-- foo.c
|   `-- Makefile.am
|-- Makefile.am
`-- src
    |-- bar.c
    `-- Makefile.am

You can now add two instances of Gnulib to your project in separate source trees: 

~/src/libfoo$ gnulib-tool --import --lib=libgnu --source-base=gnulib \
              --m4-base=gnulib/m4 --macro-prefix=gl strndup
~/src/libfoo$ gnulib-tool --import --lib=libgnutools \
              --source-base=src/gnulib --m4-base=src/gnulib/m4 \
              --macro-prefix=gl_tools getopt-gnu

The first one will import the module strndup in gnulib and the second one will import getopt-gnu in src/gnulib and you will end up with the following source tree (many files omitted in the interest of brevity): 

.
|-- configure.ac
|-- gnulib
|   |-- m4
|   |-- strndup.c
|-- lib
|   |-- foo.c
|   `-- Makefile.am
|-- Makefile.am
`-- src
    |-- bar.c
    |-- gnulib
    |   |-- getopt.c
    |   |-- getopt.in.h
    |   |-- m4
    `-- Makefile.am

As discussed in Bundling the unit tests of the Gnulib modules, you may not use ‘--with-tests’ for this project since the configure.ac is shared.

Integration with your code is basically the same as outlined in Initial import with the one exception that you have to add both the macro gl_EARLY and the macro gl_tools_EARLY to your configure.ac (and of course also both macros gl_INIT and gl_tools_INIT). Obviously the name of the second macro is dependent on the value of the --macro-prefix option in your gnulib-tool invocation. 

...
AC_PROG_CC
gl_EARLY
gl_tools_EARLY
...
# For gnulib.
gl_INIT
gl_tools_INIT
...

Also as outlined in Initial import you will have to add compiler and linker flags. For the library you might have to add something along the line of the following to your Makefile.am: 

...
AM_CPPFLAGS = -I$(top_srcdir)/gnulib -I$(top_builddir)/gnulib
...
libfoo_la_LIBADD = $(top_builddir)/gnulib/libgnu.la
...

Correspondingly for the programs you will have to add something like this: 

...
AM_CPPFLAGS = -I$(top_srcdir)/src/gnulib -I$(top_builddir)/src/gnulib
...
LDADD = $(top_builddir)/src/gnulib/libgnutools.la
...

The name of the library that you have pass in the linker option depends on the --lib option in gnulib-tool invocation.

Next: , Previous: , Up: Invoking gnulib-tool   [Contents][Index]

3.11 Caveat: gettextize and autopoint users

The programs gettextize and autopoint, part of GNU gettext, import or update the internationalization infrastructure. Some of this infrastructure, namely ca. 20 Autoconf macro files and the config.rpath file, is also contained in Gnulib and may be imported by gnulib-tool. The use of gettextize or autopoint will therefore overwrite some of the files that gnulib-tool has imported, and vice versa.

Avoiding to use gettextize (manually, as package maintainer) or autopoint (as part of a script like autoreconf or autogen.sh) is not the solution: These programs also import the infrastructure in the po/ and optionally in the intl/ directory.

The copies of the conflicting files in Gnulib are more up-to-date than the copies brought in by gettextize and autopoint. When a new gettext release is made, the copies of the files in Gnulib will be updated immediately.

The choice of which version of gettext to require depends on the needs of your package. For a package that wants to comply to GNU Coding Standards, the steps are:

  1. When you run gettextize, always use the gettextize from the matching GNU gettext release. For the most recent Gnulib checkout, this is the newest release found on https://ftp.gnu.org/gnu/gettext/. For an older Gnulib snapshot, it is the release that was the most recent release at the time the Gnulib snapshot was taken.
  2. After running gettextize, invoke gnulib-tool and import the gettext module. Also, copy the latest version of gnulib’s build-aux/po/Makefile.in.in to your po/ directory (this is done for you if you use gnulib’s autogen.sh script).
  3. If you get an error message like *** error: gettext infrastructure mismatch: using a Makefile.in.in from gettext version ... but the Autoconf macros are from gettext version ..., it means that a new GNU gettext release was made, and its Autoconf macros were integrated into Gnulib and now mismatch the po/ infrastructure. In this case, fetch and install the new GNU gettext release and run gettextize followed by gnulib-tool.

On the other hand, if your package is not as concerned with compliance to the latest standards, but instead favors development on stable environments, the steps are:

  1. Determine the oldest version of gettext that you intend to support during development (at this time, gnulib recommends going no older than version 0.17). Run autopoint (not gettextize) to copy infrastructure into place (newer versions of gettext will install the older infrastructure that you requested).
  2. Invoke gnulib-tool, and import the gettext-h module.

Regardless of which approach you used to get the infrastructure in place, the following steps must then be used to preserve that infrastructure (gnulib’s autogen.sh script follows these rules):

  1. When a script of yours run autopoint, invoke gnulib-tool afterwards.
  2. When you invoke autoreconf after gnulib-tool, make sure to not invoke autopoint a second time, by setting the AUTOPOINT environment variable, like this: 
    $ env AUTOPOINT=true autoreconf --install

Next: , Previous: , Up: Invoking gnulib-tool   [Contents][Index]

3.12 Handling Gnulib’s own message translations

Gnulib provides some functions that emit translatable messages using GNU gettext. The ‘gnulib’ domain at the Translation Project collects translations of these messages, which you should incorporate into your own programs.

The recommended way to achieve this is that your package depends on the package ‘gnulib-l10n’. This package contains the Gnulib localizations as .mo files.

In order to use this method, you must – in each program that might use Gnulib code – add an extra line to the part of the program that initializes locale-dependent behavior. Where you would normally write something like: 

  setlocale (LC_ALL, "");
  bindtextdomain (PACKAGE, LOCALEDIR);
  textdomain (PACKAGE);

you should add an additional bindtextdomain call to inform gettext of where the MO files for the extra message domain may be found: 

  bindtextdomain ("gnulib", GNULIB_LOCALEDIR);

Since you do not change the textdomain call, the default message domain for your program remains the same and your own use of gettext functions will not be affected.

If your package has a DEPENDENCIES file, for the ease of installers and distributors, you should add the ‘gnulib-l10n’ dependency in this file.

If your package does not support localization, you can simplify its build process by using gnulib-tool’s --avoid=gnulib-i18n option. The package need not call bindtextdomain or textdomain, and all Gnulib-generated messages will be in American English.

Two older methods to use Gnulib localizations are deprecated:

  • The first, and older, method is to list all the source files you use from Gnulib in your own po/POTFILES.in file. This will cause all the relevant translatable strings to be included in your POT file. When you send this POT file to the Translation Project, translators will normally fill in the translations of the Gnulib strings from their “translation memory”, and send you back updated PO files. For this to work, your program should define the macro GNULIB_TEXT_DOMAIN to its own textdomain name early, before including gettext.h; you can do this by putting AC_DEFINE([GNULIB_TEXT_DOMAIN], [PACKAGE]) in your configure.ac.

    However, this process is error-prone: you might forget to list some source files, or the translator might not be using a translation memory and provide a different translation than another translator, or the translation might not be kept in sync between Gnulib and your package. It is also slow and causes substantial extra work, because a human translator must be in the loop for each language and you will need to incorporate their work on request.

  • The second method is that you pass the --po-base=directory and --po-domain=domain options to gnulib-tool, then gnulib-tool creates a separate directory with its own POTFILES.in, and fetches current translations directly from the Translation Project (using wget). The POT file in this directory will be called domain-gnulib.pot, depending on the domain you gave to the --po-domain option (typically the same as the package name). This causes these translations to reside in a separate message domain, so that they do not clash either with the translations for the main part of your package nor with those of other packages on the system that use possibly different versions of Gnulib. When you use these options, the functions in Gnulib are built in such a way that they will always use this domain regardless of the default domain set by textdomain.

    This method is deprecated because it adds complexity to your package and, additionally, mixes the “autopull” and “autogen” phases of package source preparation.

Next: , Previous: , Up: Invoking gnulib-tool   [Contents][Index]

3.13 Integration with Version Control Systems

If a project stores its source files in a version control system (VCS), such as CVS, Subversion, or Git, one needs to decide which files to commit.

In principle, all files created by gnulib-tool, except gnulib-cache.m4, can be treated like generated source files, like for example a parser.c file generated from parser.y. Alternatively, they can be considered source files and updated manually.

Here are the three different approaches in common use. Each has its place, and you should use whichever best suits your particular project and development methods.

  1. In projects which commit all source files, whether generated or not, into their VCS, the gnulib-tool generated files should all be committed. In this case, you should pass the option ‘--no-vc-files’ to gnulib-tool, which avoids alteration of VCS-related files such as .gitignore.

    Gnulib also contains files generated by make (and removed by make clean), using information determined by configure. For a Gnulib source file of the form lib/foo.in.h, the corresponding lib/foo.h is such a make-generated file. These should not be checked into the VCS, but instead added to .gitignore or equivalent.

  2. In projects which customarily omit from their VCS all files that are generated from other source files, none of these files and directories are added into the VCS. As described in Modified imports, there are two ways to keep track of options and module names that are passed to gnulib-tool. The command for restoring the omitted files depends on it:
    • If they are stored in a file other than gnulib-cache.m4, such as autogen.sh, bootstrap, bootstrap.conf, or similar, the restoration command is the entire gnulib-tool ... --import ... invocation with all options and module names.
    • If the project relies on gnulib-tool’s memory of the last used options and module names, then the file gnulib-cache.m4 in the M4 macros directory must be added to the VCS, and the restoration command is: 
      $ gnulib-tool --update

      The ‘--update’ option operates much like the ‘--add-import’ option, but it does not offer the possibility to change the way Gnulib is used. Also it does not report in the ChangeLogs the files that it had to add because they were missing.

    Most packages nowadays use the first among these two approaches. Over time, three ways of handling version control have evolved.

    In the cases (A) and (B), a “git submodule” is used to reference the precise commit of the gnulib repository, so that each developer running ‘./bootstrap --pull’ or autopull.sh will get the same version of all gnulib-provided files.

    The alternative is to always follow the newest Gnulib automatically. Note that this can cause breakages at unexpected moments, namely when a broken commit is pushed in Gnulib. It does not happen often, but it does happen.

    • (A) In this approach, the developers use a git submodule manually.

      The location of the submodule can be chosen to fit the package’s needs; here’s how to initially create the submodule in the directory gnulib: 

      $ git submodule add -- https://git.savannah.gnu.org/git/gnulib.git gnulib

      Thereafter, the developer will run this command to update the submodule to the recorded checkout level: 

      $ git submodule update --init gnulib

      Use this sequence to update to a newer version of gnulib: 

      $ git submodule update --remote gnulib
$ git add gnulib
$ ./bootstrap --bootstrap-sync

      If multiple submodules are used, the following may be useful: 

      $ git config alias.syncsub "submodule foreach git pull origin master"
$ git syncsub
    • (B) In this approach, the build-aux/bootstrap or autopull.sh program (see Programs for developing in Git checkouts) is used to aid a developer in using this setup. You copy this program (and if it’s autopull.sh, its companion files) into your package and place the copy or copies under version control. The program can be customized using bootstrap.conf which you also put under version control.
    • (C) In this approach, you write the autopull.sh and autogen.sh files by hand.

      autopull.sh is most easily written as a script that invokes 

      ./gitsub.sh pull || exit 1

      where gitsub.sh is described in Programs for developing in Git checkouts.

      autogen.sh typically contains an explicit gnulib-tool invocation, followed by 

      aclocal -I m4 \
  && autoconf \
  && autoheader && touch config.h.in \
  && automake --add-missing --copy \
  && rm -rf autom4te.cache \
  || exit $?
  3. Some projects take a “middle road”: they do commit Gnulib source files as in the first approach, but they do not commit other derived files, such as a Makefile.in generated by Automake. This increases the size and complexity of the repository, but can help occasional contributors by not requiring them to have a full Gnulib checkout to do a build, and all developers by ensuring that all developers are working with the same version of Gnulib in the repository. It also supports multiple Gnulib instances within a project. It remains important not to commit the make-generated files, as described above.

Next: , Previous: , Up: Invoking gnulib-tool   [Contents][Index]

3.14 Bundling the unit tests of the Gnulib modules

You can bundle the unit tests of the Gnulib modules together with your package, through the ‘--with-tests’ option. Together with ‘--with-tests’, you also specify the directory for these tests through the ‘--tests-base’ option. Of course, you need to add this directory to the SUBDIRS variable in the Makefile.am of the parent directory.

The advantage of having the unit tests bundled is that when your program has a problem on a particular platform, running the unit tests may help determine quickly if the problem is on Gnulib’s side or on your package’s side. Also, it helps verifying Gnulib’s portability, of course.

The unit tests will be compiled and run when the user runs ‘make check’. When the user runs only ‘make’, the unit tests will not be compiled.

In the SUBDIRS variable, it is useful to put the Gnulib tests directory after the directory containing the other tests, not before: 

SUBDIRS = gnulib-lib src man tests gnulib-tests

This will ensure that on platforms where there are test failures in either directory, users will see and report the failures from the tests of your program.

Note: In packages which use more than one invocation of gnulib-tool in the scope of the same configure.ac, you cannot use ‘--with-tests’. You will have to use a separate configure.ac in this case.

Previous: , Up: Invoking gnulib-tool   [Contents][Index]

3.15 Avoiding unnecessary checks and compilations

In some cases, a module is needed by another module only on specific platforms. But when a module is present, its Autoconf checks are always executed, and its Makefile.am additions are always enabled. So it can happen that some Autoconf checks are executed and some source files are compiled, although no other module needs them on this particular platform, just in case some other module would need them.

The option ‘--conditional-dependencies’ enables an optimization of configure checks and Makefile.am snippets that avoids this. With this option, whether a module is considered “present” is no longer decided when gnulib-tool is invoked, but later, when configure is run. This applies to modules that were added as dependencies while gnulib-tool was run; modules that were passed on the command line explicitly are always “present”.

For example, the timegm module needs, on platforms where the system’s timegm function is missing or buggy, a replacement that is based on a function mktime_internal. The module mktime-internal that provides this function provides it on all platforms. So, by default, the file mktime-internal.c will be compiled on all platforms, even on glibc and BSD systems which have a working timegm function. When the option ‘--conditional-dependencies’ is given, on the other hand, and if mktime-internal was not explicitly required on the command line, the file mktime-internal.c will only be compiled on the platforms where the timegm needs them.

Conditional dependencies are specified in the module description by putting the condition on the same line as the dependent module, enclosed in brackets. The condition is a boolean shell expression that can assume that the configure.ac snippet from the module description has already been executed. In the example above, the dependency from timegm to mktime-internal is written like this: 

Depends-on:
...
mktime-internal [test $HAVE_TIMEGM = 0 || test $REPLACE_TIMEGM = 1]
...

Note: The option ‘--conditional-dependencies’ cannot be used together with the option ‘--with-tests’. It also cannot be used when a package uses gnulib-tool for several subdirectories, with different values of ‘--source-base’, in the scope of a single configure.ac file.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

4 Writing modules

This chapter explains how to write modules of your own, either to extend Gnulib for your own package (see Extending Gnulib), or for inclusion in gnulib proper.

The guidelines in this chapter do not necessarily need to be followed for using gnulib-tool. They merely represent a set of good practices. Following them will result in a good structure of your modules and in consistency with gnulib.

Next: , Up: Writing modules   [Contents][Index]

4.1 Source code files

Every API (C functions or variables) provided should be declared in a header file (.h file) and implemented in one or more implementation files (.c files). The separation has the effect that users of your module need to read only the contents of the .h file and the module description in order to understand what the module is about and how to use it—not the entire implementation. Furthermore, users of your module don’t need to repeat the declarations of the functions in their code, and are likely to receive notification through compiler errors if you make incompatible changes to the API (like, adding a parameter or changing the return type of a function).

Next: , Previous: , Up: Writing modules   [Contents][Index]

4.2 Header files

The .h file should declare the C functions and variables that the module provides.

The .h file should be stand-alone. That is, it does not require other .h files to be included before. Rather, it includes all necessary .h files by itself.

It is a tradition to use CPP tricks to avoid parsing the same header file more than once, which might cause warnings. The trick is to wrap the content of the header file (say, foo.h) in a block, as in: 

#ifndef FOO_H
# define FOO_H
...
body of header file goes here
...
#endif /* FOO_H */

Whether to use FOO_H or _FOO_H is a matter of taste and style. The C99 and C11 standards reserve all identifiers that begin with an underscore and either an uppercase letter or another underscore, for any use. Thus, in theory, an application might not safely assume that _FOO_H has not already been defined by a library. On the other hand, using FOO_H will likely lead the higher risk of collisions with other symbols (e.g., KEY_H, XK_H, BPF_H, which are CPP macro constants, or COFF_LONG_H, which is a CPP macro function). Your preference may depend on whether you consider the header file under discussion as part of the application (which has its own namespace for CPP symbols) or a supporting library (that shouldn’t interfere with the application’s CPP symbol namespace).

Adapting C header files for use in C++ applications can use another CPP trick, as in: 

# ifdef __cplusplus
extern "C"
{
# endif
...
body of header file goes here
...
# ifdef __cplusplus
}
# endif

The idea here is that __cplusplus is defined only by C++ implementations, which will wrap the header file in an ‘extern "C"’ block. Again, whether to use this trick is a matter of taste and style. While the above can be seen as harmless, it could be argued that the header file is written in C, and any C++ application using it should explicitly use the ‘extern "C"’ block itself. Your preference might depend on whether you consider the API exported by your header file as something available for C programs only, or for C and C++ programs alike.

Note that putting a #include in an extern "C" { ... } block yields a syntax error in C++ mode on some platforms (e.g., glibc systems with g++ v3.3 to v4.2, AIX). For this reason, it is recommended to place the #include before the extern "C" block.

Next: , Previous: , Up: Writing modules   [Contents][Index]

4.3 Implementation files

The .c file or files implement the functions and variables declared in the .h file.

Include ordering

Every implementation file must start with ‘#include <config.h>’. This is necessary for activating the preprocessor macros that are defined on behalf of the Autoconf macros. Some of these preprocessor macros, such as _GNU_SOURCE, would have no effect if defined after a system header file has already been included.

Then comes the ‘#include "..."’ specifying the header file that is being implemented. Putting this right after ‘#include <config.h>’ has the effect that it verifies that the header file is self-contained.

Then come the system and application headers. It is customary to put all the system headers before all application headers, so as to minimize the risk that a preprocessor macro defined in an application header confuses the system headers on some platforms.

In summary:

  • First comes #include <config.h>.
  • Second comes the #include "..." specifying the module being implemented.
  • Then come all the #include <...> of system or system-replacement headers, in arbitrary order.
  • Then come all the #include "..." of gnulib and application headers, in arbitrary order.

Next: , Previous: , Up: Writing modules   [Contents][Index]

4.4 Specification

The specification of a function should answer at least the following questions:

  • What is the purpose of the function?
  • What are the arguments?
  • What is the return value?
  • What happens in case of failure? (Exit? A specific return value? Errno set?)
  • Memory allocation policy: If pointers to memory are returned, are they freshly allocated and supposed to be freed by the caller?

Where to put the specification describing exported functions? Three practices are used in gnulib:

  • The specification can be as comments in the header file, just above the function declaration.
  • The specification can be as comments in the implementation file, just above the function definition.
  • The specification can be in texinfo format, so that it gets included in the gnulib manual.

In any case, the specification should appear in just one place, unless you can ensure that the multiple copies will always remain identical.

The advantage of putting it in the header file is that the user only has to read the include file normally never needs to peek into the implementation file(s).

The advantage of putting it in the implementation file is that when reviewing or changing the implementation, you have both elements side by side.

The advantage of texinfo formatted documentation is that it is easily published in HTML or Info format.

Currently (as of 2020), 70% of gnulib uses the first practice, 25% of gnulib uses the second practice, and a small minority uses the texinfo practice.

Next: , Previous: , Up: Writing modules   [Contents][Index]

4.5 Module description

For the module description, you can start from an existing module’s description, or from a blank one: module/TEMPLATE for a normal module, or module/TEMPLATE-TESTS for a unit test module. Some more fields are possible but rarely used. Use module/TEMPLATE-EXTENDED if you want to use one of them.

Module descriptions have the following fields. Absent fields are equivalent to fields with empty contents.

Description

This field should contain a concise description of the module’s functionality. One sentence is enough. For example, if it defines a single function ‘frob’, the description can be ‘frob() function: frobnication.’ Gnulib’s documentation generator will automatically convert the first part to a hyperlink when it has this form.

Status

This field is either empty/absent, or contains the word ‘obsolete’. In the latter case, gnulib-tool will, unless the option --with-obsolete is given, omit it when it used as a dependency. It is good practice to also notify the user about an obsolete module. This is done by putting into the ‘Notice’ section (see below) text like ‘This module is obsolete.’

Notice

This field contains text that gnulib-tool will show to the user when the module is used. This can be a status indicator like ‘This module is obsolete.’ or additional advice. Do not abuse this field.

Applicability

This field is either empty/absent, or contains the word ‘all’. It describes to which Makefile.am the module is applied. By default, a normal module is applied to source_base/Makefile.am (normally lib/Makefile.am), whereas a module ending in -tests is applied to tests_base/Makefile.am (normally tests/Makefile.am). If this field is ‘all’, it is applied to both Makefile.ams. This is useful for modules which provide Makefile.am macros rather than compiled source code.

Usable-in-testdir

This field should contain ‘no’ if the module cannot be used in a test directory created with gnulib-tool --create-testdir.

Files

This field contains a newline separated list of the files that are part of the module. gnulib-tool copies these files into the package that uses the module.

This list is typically ordered by importance: First comes the header file, then the implementation files, then other files.

It is possible to have the same file mentioned in multiple modules. That is, if the maintainers of that module agree on the purpose and future of said file.

Depends-on

This field contains a newline separated list of the modules that are required for the proper working of this module. gnulib-tool includes each required module automatically, unless it is specified with option --avoid or it is marked as obsolete and the option --with-obsolete is not given.

A test modules foo-tests implicitly depends on the corresponding non-test module foo. foo implicitly depends on foo-tests if the latter exists and if the option --with-tests has been given.

Tests modules can depend on non-tests modules. Non-tests modules should not depend on tests modules. (Recall that tests modules are built in a separate directory.)

Each listed required module may be declared a conditional dependency. This is indicated by placing the condition for the dependency on the same line, enclosed in brackets, after the name of the required module. The condition is a shell expression that is run after the module’s configure.ac statements. For example: 

strtoull   [test $ac_cv_func_strtoumax = no]

Lines starting with # are recognized as comments and are ignored.

configure.ac-early

This field contains configure.ac stuff (Autoconf macro invocations and shell statements) that are logically placed early in the configure.ac file: right after the AC_PROG_CC invocation. This section is adequate for statements that modify CPPFLAGS, as these can affect the results of other Autoconf macros.

configure.ac

This field contains configure.ac stuff (Autoconf macro invocations and shell statements).

It is forbidden to add items to the CPPFLAGS variable here, other than temporarily, as these could affect the results of other Autoconf macros.

We avoid adding items to the LIBS variable, other than temporarily. Instead, the module can export an Autoconf-substituted variable that contains link options. The user of the module can then decide to which executables to apply which link options. Recall that a package can build executables of different kinds and purposes; having all executables link against all libraries is inappropriate.

If the statements in this section grow larger than a couple of lines, we recommend moving them to a .m4 file of their own.

Makefile.am

This field contains Makefile.am statements. Variables like lib_SOURCES are transformed to match the name of the library being built in that directory. For example, lib_SOURCES may become libgnu_a_SOURCES (for a plain library) or libgnu_la_SOURCES (for a libtool library). Therefore, the normal way of having an implementation file lib/foo.c compiled unconditionally is to write 

lib_SOURCES += foo.c
Include

This field contains the preprocessor statements that users of the module need to add to their source code files. Typically it’s a single include statement. A shorthand is allowed: You don’t need to write the word “#include”, just the name of the include file in the way it will appear in an include statement. Example: 

"foo.h"
Link

This field contains the set of libraries that are needed when linking libraries or executables that use this module. Often this will be written as a reference to a Makefile variable. Please write them one per line, so that gnulib-tool can remove duplicates when presenting a summary to the user. Example: 

$(POW_LIBM)
$(LTLIBICONV) when linking with libtool, $(LIBICONV) otherwise

When this field is omitted, it defaults to the union of the Link field of the dependencies.

License

This field specifies the license that governs the source code parts of this module. See Copyright for details. Be sure to place, in every source code file, a copyright notice and the appropriate license notice, taken from the etc/license-notices/ directory.

Maintainer

This field specifies the persons who have a definitive say about proposed changes to this module. You don’t need to mention email addresses here: they can be inferred from the ChangeLog file.

Please put at least one person here. We don’t like unmaintained modules.

Next: , Previous: , Up: Writing modules   [Contents][Index]

4.6 Autoconf macros

For a module foo, an Autoconf macro file m4/foo.m4 is typically created when the Autoconf macro invocations for the module are longer than one or two lines.

The name of the main entry point into this Autoconf macro file is typically gl_FOO. For modules outside Gnulib that are not likely to be moved into Gnulib, please use a prefix specific to your package: gt_ for GNU gettext, cu_ for GNU coreutils, etc.

For modules that define a function foo, the entry point is called gl_FUNC_FOO instead of gl_FOO. For modules that provide a header file with multiple functions, say foo.h, the entry point is called gl_FOO_H or gl_HEADER_FOO_H. This convention is useful because sometimes a header and a function name coincide (for example, fcntl and fcntl.h).

For modules that provide a replacement, it is useful to split the Autoconf macro into two macro definitions: one that detects whether the replacement is needed and requests the replacement by setting a HAVE_FOO variable to 0 or a REPLACE_FOO variable to 1 (this is the entry point, say gl_FUNC_FOO), and one that arranges for the macros needed by the replacement code lib/foo.c (typically called gl_PREREQ_FOO). The reason of this separation is

  1. to make it easy to update the Autoconf macros when you have modified the source code file: after changing lib/foo.c, all you have to review is the Depends-on section of the module description and the gl_PREREQ_FOO macro in the Autoconf macro file.
  2. The Autoconf macros are often large enough that splitting them eases maintenance.

Autoconf macro files in Gnulib all start with a header consisting of

  1. A comment line with the file name. This is useful because in some cases the generated aclocal.m4 file does not contain a reference to the .m4 file but its entire contents. The comment makes it clear which .m4 file is where in the aclocal.m4 file.
  2. A comment line with a serial number. This is useful when people use the ‘aclocal --install’ command. aclocal will then refrain from copying a file with a smaller serial number onto a file with a larger serial number. The serial number should be a positive integer on the main branch, or a positive fractional number on a stable branch.
  3. The copyright and license header, as usual.

Next: , Previous: , Up: Writing modules   [Contents][Index]

4.7 Making proper use of AC_LIBOBJ

Source files that provide a replacement should be only compiled on the platforms that need this replacement. While it is actually possible to compile a .c file whose contents is entirely #ifdef’ed out on the platforms that don’t need the replacement, this practice is discouraged because

  • It makes the build time longer than needed, by invoking the compiler for nothing.
  • It produces a .o file that suggests that a replacement was needed.
  • Empty object files produce a linker warning on some platforms: MSVC.

The typical idiom for invoking AC_LIBOBJ is thus the following, in the module description: 

if test $HAVE_FOO = 0 || test $REPLACE_FOO = 1; then
  AC_LIBOBJ([foo])
  gl_PREREQ_FOO
fi

Important: Do not place AC_LIBOBJ invocations in the Autoconf macros in the m4/ directory. The purpose of the Autoconf macros is to determine what features or bugs the platform has, and to make decisions about which replacements are needed. The purpose of the configure.ac and Makefile.am sections of the module descriptions is to arrange for the replacements to be compiled. Source file names do not belong in the m4/ directory.

When an AC_LIBOBJ invocation is unconditional, it is simpler to just have the source file compiled through an Automake variable augmentation: In the Makefile.am section write 

lib_SOURCES += foo.c

When a module description contains an AC_LIBOBJ([foo]) invocation, you must list the source file lib/foo.c in the Files section. This is needed even if the module depends on another module that already lists lib/foo.c in its Files section – because your module might be used among the test modules (in the directory specified through ‘--tests-base’) and the other module among the main modules (in the directory specified through ‘--source-base’), and in this situation, the AC_LIBOBJ([foo]) of your module can only be satisfied by having foo.c be present in the tests source directory as well.

Next: , Previous: , Up: Writing modules   [Contents][Index]

4.8 Unit test modules

A unit test that is a simple C program usually has a module description as simple as this: 

Files:
tests/test-foo.c
tests/macros.h

Depends-on:

configure.ac:

Makefile.am:
TESTS += test-foo
check_PROGRAMS += test-foo

The test program tests/test-foo.c often has the following structure:

  • First comes the obligatory ‘#include <config.h>’.
  • Second comes the include of the header file that declares the API being tested. Including it here verifies that said header file is self-contained.
  • Then come other includes. In particular, the file macros.h is often used here. It contains a convenient ASSERT macro.

The body of the test, then, contains many ASSERT invocations. When a test fails, the ASSERT macro prints the line number of the failing statement, thus giving you, the developer, an idea of which part of the test failed, even when you don’t have access to the machine where the test failed and the reporting user cannot run a debugger.

Sometimes it is convenient to write part of the test as a shell script. (For example, in areas related to process control or interprocess communication, or when different locales should be tried.) In these cases, the typical module description is like this: 

Files:
tests/test-foo.sh
tests/test-foo.c
tests/macros.h

Depends-on:

configure.ac:

Makefile.am:
TESTS += test-foo.sh
TESTS_ENVIRONMENT += FOO_BAR='@FOO_BAR@'
check_PROGRAMS += test-foo

Here, the TESTS_ENVIRONMENT variable can be used to pass values determined by configure or by the Makefile to the shell script, as environment variables. The Autoconf values EXEEXT and srcdir are already provided as environment variables, through an initial value of TESTS_ENVIRONMENT that gnulib-tool puts in place.

Regardless of the specific form of the unit test, the following guidelines should be respected:

  • A test indicates success by exiting with exit code 0. It should normally not produce output in this case. (Output to temporary files that are cleaned up at the end of the test are possible, of course.)
  • A test indicates failure by exiting with an exit code different from 0 and 77, typically 1. It is useful to print a message about the failure in this case. The ASSERT macro already does so.
  • A test indicates "skip", that is, that most of its interesting functionality could not be performed, through a return code of 77. A test should also print a message to stdout or stderr about the reason for skipping. For example: 
      fputs ("Skipping test: multithreading not enabled\n", stderr);
  return 77;

    Such a message helps detecting bugs in the autoconf macros: A simple message ‘SKIP: test-foo’ does not sufficiently catch the attention of the user.

Previous: , Up: Writing modules   [Contents][Index]

4.9 Incompatible changes

Incompatible changes to Gnulib modules should be mentioned in Gnulib’s NEWS file. Incompatible changes here mean that existing source code may not compile or work any more.

We don’t mean changes in the binary interface (ABI), since

  1. Gnulib code is used in source-code form.
  2. The user who distributes libraries that contain Gnulib code is supposed to bump the version number in the way described in the Libtool documentation before every release.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

5 Extending Gnulib

Gnulib modules are intended to be suitable for widespread use. Most problems with Gnulib can and should be fixed in a generic way, so that all of Gnulib’s users can benefit from the change. But occasionally a problem arises that is difficult or undesirable to fix generically, or a project that uses Gnulib may need to work around an issue before the Gnulib maintainers commit a final fix. Maintainers may also want to add their own pools of modules to projects as Gnulib “staging areas.”

The obvious way to make local changes to Gnulib modules is to use gnulib-tool to check out pristine modules, then to modify the results in-place. This works well enough for short-lived experiments. It is harder to keep modified versions of Gnulib modules for a long time, even though Git (or another distributed version control systems) can help out a lot with this during the development process.

Git, however, doesn’t address the distribution issue. When a package “foobar” needs a modified version of, say, stdint.in.h, it either has to put a comment into foobar/autogen.sh saying “Attention! This doesn’t work with a pristine Gnulib, you need this and that patch after checking out Gnulib,” or it has to use the ‘--avoid=stdint-h’ option and provide the modified stdint-h module in a different directory.

The --local-dir option to gnulib-tool solves this problem. It allows the package to override or augment Gnulib. This means:

In a release tarball, you can distribute the contents of this --local-dir directory that will be combinable with newer versions of Gnulib, barring incompatible changes to Gnulib.

If the --local-dir=directory option is specified, then gnulib-tool looks in directory whenever it reads a file from the Gnulib directory. Suppose gnulib-tool is looking for file. Then:

You can specify the --local-dir multiple times. In this case, the first specified directory has the highest precedence. That is, a file found in one directory will shadow any file and file.diff in the later directories and in the Gnulib directory. And a file file.diff found in one directory will be applied on top of the combination of file and file.diff files found in the later directories and in the Gnulib directory.

Please make wise use of this option. It also allows you to easily hold back modifications you make to Gnulib macros in cases it may be better to share them.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

6 Miscellaneous Notes

Next: , Up: Miscellaneous Notes   [Contents][Index]

6.1 Out of memory handling

The gnulib API does not have a standard error code for the out of memory error condition. Instead of adding a non-standard error code, gnulib has chosen to adopt a different strategy. Out of memory handling happens in rare situations, but performing the out of memory error handling after almost all API function invocations pollute your source code and might make it harder to spot more serious problems. The strategy chosen improves code readability and robustness.

For most applications, aborting the application with an error message when the out of memory situation occurs is the best that can be wished for. This is how the library behaves by default (using the ‘xalloc-die’ module).

However, we realize that some applications may not want to abort execution in any situation. Gnulib supports a hook to let the application regain control and perform its own cleanups when an out of memory situation has occurred. The application can define a function (having a void prototype, i.e., no return value and no parameters) and set the library variable xalloc_die to that function. The variable should be declared as follows. 

extern void (*xalloc_die) (void);

Gnulib will invoke this function if an out of memory error occurs. Note that the function should not return. Of course, care must be taken to not allocate more memory, as that will likely also fail.

Next: , Previous: , Up: Miscellaneous Notes   [Contents][Index]

6.2 Obsolete modules

Modules can be marked obsolete. This means that the problems they fix don’t occur any more on the platforms that are reasonable porting targets now. gnulib-tool warns when obsolete modules are mentioned on the command line, and by default ignores dependencies from modules to obsolete modules. When you pass the option --with-obsolete to gnulib-tool, dependencies to obsolete modules will be included, however, unless blocked through an --avoid option. This option is useful if your package should be portable even to very old platforms.

In order to mark a module obsolete, you need to add this to the module description: 

Status:
obsolete

Notice:
This module is obsolete.

Next: , Previous: , Up: Miscellaneous Notes   [Contents][Index]

6.3 Extra tests modules

Test modules can be marked with some special status attributes. When a test module has such an attribute, gnulib-tool --import will not include it by default.

The supported status attributes are:

c++-test

Indicates that the test is testing C++ interoperability. Such a test is useful in a C++ or mixed C/C++ package, but is useless in a C package.

longrunning-test

Indicates that the test takes a long time to compile or execute (more than five minutes or so). Such a test is better avoided in a release that is made for the general public.

privileged-test

Indicates that the test will request special privileges, for example, ask for the superuser password. Such a test may hang when run non-interactively and is therefore better avoided in a release that is made for the general public.

unportable-test

Indicates that the test is known to fail on some systems, and that there is no workaround about it. Such a test is better avoided in a release that is made for the general public.

gnulib-tool --import --with-tests will not include tests marked with these attributes by default. When gnulib-tool is invoked with one of the options --with-c++-tests, --with-longrunning-tests, --with-privileged-tests, --with-unportable-tests, it will include tests despite the corresponding special status attribute. When gnulib-tool receives the option --with-all-tests, it will include all tests regardless of their status attributes.

gnulib-tool --create-testdir --with-tests and gnulib-tool --create-megatestdir --with-tests by default include all tests of modules specified on the command line, regardless of their status attributes. Tests of modules occurring as dependencies are not included by default if they have one of these status attributes. The options --with-c++-tests, --with-longrunning-tests, --with-privileged-tests, --with-unportable-tests are recognized here as well. Additionally, gnulib-tool also understands the options --without-c++-tests, --without-longrunning-tests, --without-privileged-tests, --without-unportable-tests.

In order to mark a module with a status attribute, you need to add it to the module description, like this: 

Status:
longrunning-test

If only a part of a test deserves a particular status attribute, you can split the module into a primary and a secondary test module, say foo-tests and foo-extra-tests. Then add a dependency from foo-tests to foo-extra-tests, and mark the foo-extra-tests with the particular status attribute.

Next: , Previous: , Up: Miscellaneous Notes   [Contents][Index]

6.4 Modules that modify the way other modules work

The normal way to design modules is that each module has its own code, and the module dependencies provide the facilities on which this code can rely. But sometimes it is necessary to use more advanced techniques. For example:

  • You may want to have optional module dependencies: Let module A use facilities provided by module B, if module B is present, but without requiring that module B is present.
  • A module can indicate support for particular behaviours. For example, Gnulib has a module ‘sigpipe’ that requests POSIX compatible SIGPIPE behaviour from all other modules – something that is not enabled by default. Or consider the ‘nonblocking’ module, that is an indicator that all I/O functions should handle non-blocking file descriptors – something that, equally, is not enabled by default.
  • A module can indicate to other modules that they can rely on certain guarantees, and thus omit specific code. For example, when Gnulib’s ‘malloc-gnu’ module is present, you can omit code that test n against zero when you call malloc (n).

Be aware that these advanced techniques likely cause breakage in the situation of multiple gnulib-tool invocations in the scope of a single configure file. This is because the question “is module B present?” does not have a unique answer in such situations. gnulib-tool has support for these techniques in the situation of --create-testdir (without option --two-configures), which basically has two gnulib-tool invocations, one for a set of modules that end up in gllib, and one for the set of modules that end up in gltests. But you should be aware that this does not cover the general situation.

Which technique to use, depends on the answer to the question: “If my module occurs among the modules of gltests, should it have an effect on the modules in gllib?”

If the answer is “no”, your module description should invoke the Autoconf macro gl_MODULE_INDICATOR. This Autoconf macro takes one argument: the name of your module. The effect of gl_MODULE_INDICATOR([my-module]) is to define, in config.h, a C macro GNULIB_MY_MODULE that indicates whether your macro is considered to be present. This works even when your macro is used in gltests: GNULIB_MY_MODULE will then evaluate to 1 in gltests but to 0 in gllib.

If the answer is “yes”, you have two techniques available. The first one is to invoke a similar Autoconf macro, named gl_MODULE_INDICATOR_FOR_TESTS. It works similarly. However, when your macro is used in gltests, GNULIB_MY_MODULE will evaluate to 1 both in gltests and in gllib.

The second one is to define a shell variable in the configure file that tells whether your module is present, through use of m4_divert_text. The Autoconf macros of a dependency module will initialize this shell variable, through ‘m4_divert_text([DEFAULTS], [my_shell_var=no])’. The Autoconf macros of your module will override this value, through ‘m4_divert_text([INIT_PREPARE], [my_shell_var=yes])’. Then you can use my_shell_var in the Autoconf macros of both modules. You can find more details about this technique in the Gnulib module getopt-gnu.

Reminder: These techniques are advanced. They have the potential to cause lots of headaches if you apply them incorrectly.

Next: , Previous: , Up: Miscellaneous Notes   [Contents][Index]

6.5 A C++ namespace for gnulib

The function definitions provided by Gnulib (.c code) are meant to be compiled by a C compiler. The header files (.h files), on the other hand, can be used in either C or C++.

By default, when used in a C++ compilation unit, the .h files declare the same symbols and overrides as in C mode, except that functions defined by Gnulib or by the system are declared as ‘extern "C"’.

It is also possible to indicate to Gnulib to provide many of its symbols in a dedicated C++ namespace. If you define the macro GNULIB_NAMESPACE to an identifier, many functions will be defined in the namespace specified by the identifier instead of the global namespace. For example, after you have defined 

#define GNULIB_NAMESPACE gnulib

at the beginning of a compilation unit, Gnulib’s <fcntl.h> header file will make available the open function as gnulib::open. The symbol open will still refer to the system’s open function, with its platform specific bugs and limitations.

The symbols provided in the Gnulib namespace are those for which the corresponding header file contains a _GL_CXXALIAS_RPL or _GL_CXXALIAS_SYS macro invocation.

The benefits of this namespace mode are:

  • Gnulib defines fewer symbols as preprocessor macros. For example, on a platform where open has to be overridden, Gnulib normally does #define open rpl_open. If your package has a class with a member open, for example a class foo with a method foo::open, then if you define this member in a compilation unit that includes <fcntl.h> and use it in a compilation unit that does not include <fcntl.h>, or vice versa, you will get a link error. Worse: You will not notice this problem on the platform where the system’s open function works fine. This problem goes away in namespace mode.
  • It provides a safety check whether the set of modules your package requests from Gnulib is sufficient. For example, if you use the function gnulib::open in your code, and you forgot to request the module ‘open’ from Gnulib, you will get a compilation error (regardless of the platform).

The drawback of this namespace mode is that the system provided symbols in the global namespace are still present, even when they contain bugs that Gnulib fixes. For example, if you call open (...) in your code, it will invoke the possibly buggy system function, even if you have requested the module ‘open’ from gnulib-tool.

You can turn on the namespace mode in some compilation units and keep it turned off in others. This can be useful if your package consists of an application layer that does not need to invoke POSIX functions and an operating system interface layer that contains all the OS function calls. In such a situation, you will want to turn on the namespace mode for the application layer—to avoid many preprocessor macro definitions—and turn it off for the OS interface layer—to avoid the drawback of the namespace mode, mentioned above.

Next: , Previous: , Up: Miscellaneous Notes   [Contents][Index]

6.6 License Texinfo sources

Gnulib provides copies of the GNU GPL, GNU LGPL, GNU Affero GPL, and GNU FDL licenses in Texinfo form. (The master location is https://www.gnu.org/licenses/). These Texinfo documents do not have any node names and structures built into them; for your manual, you should @include them in an appropriate @node.

The conventional name for the GPL node is ‘Copying’ and for the FDL ‘GNU Free Documentation License’. The LGPL doesn’t seem to have a conventional node name.

Of course the license texts themselves should not be changed at all.

The recommended way to make use of these license files, consistently with current practice, is as follows:

  • The code license (GNU GPL, GNU LGPL, or GNU Affero GPL) is usually present as a file in the top-level directory. This is true not only for the release tarballs, but also in the VCS repository. The file is typically named ‘COPYING’ for the GNU GPL, or ‘COPYING.LIB’ or ‘COPYING.LESSER’ for the GNU LGPL. The presence of this file fulfills a legal obligation; see https://www.gnu.org/licenses/gpl-faq.html#WhyMustIInclude.

    To make use of the code license in your documentation, you may request one of the modules gpl-3.0, gpl-2.0, lgpl-3.0, lgpl-2.1, agpl-3.0, through a gnulib-tool invocation. Or you may copy the relevant Texinfo file directly into your VCS repository. Both approaches are equally good. The Texinfo file changes very rarely.

  • The documentation license file (GNU FDL) is usually not present as a file in the top-level directory, because that would be ambiguous: When you use the GNU FDL, you need to specify the Invariant Sections, the Front-Cover Texts, and the Back-Cover Texts.

    To make use of this documentation license, copy the relevant Texinfo file (doc/fdl-1.3.texi) into your VCS repository. This makes sure that anyone who receives a copy of your VCS repository has also received a copy of the documentation license. In the documentation, also state what are the Invariant Sections, the Front-Cover Texts, and the Back-Cover Texts.

We recommend to place the licenses as appendices at the end of the manual, right before any indices. For the FDL, we suggest the following @menu entry: 

* GNU Free Documentation License::  License for copying this manual

For any @detailmenu entries, we suggest the following: 

Copying This Manual

* GNU Free Documentation License::     Copying and sharing this manual

And for actual inclusion of the FDL itself, we suggest the following: 

@node GNU Free Documentation License
@appendix GNU Free Documentation License

@include fdl.texi

Next: , Previous: , Up: Miscellaneous Notes   [Contents][Index]

6.7 Building gnulib

If you wish to help the gnulib development effort with build logs for your favorite platform, you may perform these steps:

  1. Prerequisites tools

    Install the proper development tools. To build and test all of Gnulib, you will need development tools for the programming languages C, C++, Python, and Perl, along with standard POSIX utilities such as awk, make, and sh. You will also need development tools that include Autoconf, Automake, Bison, Gettext, Git, GNU M4, Gperf, Libtool, and Texinfo. Some of these tools are needed only by some modules. More details can be found in Gnulib’s DEPENDENCIES file.

  2. Obtain Gnulib

    See https://www.gnu.org/software/gnulib/ for how to get the current Gnulib sources via Git.

  3. Create gnulib directory

    On a machine with GNU development tools installed and with a gnulib git checkout, use 

    gnulib-tool --create-testdir --with-tests --dir=...

    Alternatively, pick a small set of modules and run 

    gnulib-tool --create-megatestdir --with-tests --dir=... autobuild MODULES

    (You can’t do this with all of Gnulib at once: gnulib-tool would run for a week and produce a directory that takes more than 100 GB, maybe even 1 TB, of disk space.)

  4. Transfer gnulib directory

    Transfer this directory to a build machine (HP-UX, Cygwin, or whatever). Often it is easier to transfer one file, and this can be achieved by running, inside the directory the following commands: 

    ./configure
make dist

    And then transferring the dummy-0.tar.gz file.

  5. Build modules

    On the build machine, run ./do-autobuild (or "nohup ./do-autobuild"). It creates a directory logs/ with a log file for each module.

Previous: , Up: Miscellaneous Notes   [Contents][Index]

6.8 Gnulib Git Bundle

To provide a serialized archival copy of the Gnulib Git repository we publish Git Bundles (https://git-scm.com/docs/git-bundle) of Gnulib at https://ftp.gnu.org/gnu/gnulib/. These may be useful if Savannah happens to be offline or if you want to have a GnuPG signed confirmation of the Gnulib content.

The files are named like gnulib-YYYYMMDD.bundle, for example gnulib-20260109.bundle, where YYYYMMDD corresponds to the Git commit date (in UTC0) of the last commit on the master branch in the bundle.

After downloading the Git bundle you may use it to create a local gnulib clone using normal Git commands: 

wget -nv https://ftp.gnu.org/gnu/gnulib/gnulib-20260109.bundle
git clone gnulib-20260109.bundle gnulib
cd gnulib

Below are SHA-256 and SHA3-256 checksums of known releases: 

9dae009ef9dd7cff17b74c0cda5d7a423e2ed98b4f5b7aa29a970565b0591c06  gnulib-20250303.bundle
f01e423a7ef6b48e947fabd24bb11744204f4549342416e15dc64f427caa32e2  gnulib-20250729.bundle
ae7f76abdf11d70f87170363b8f5807ec377a3ebf231499ab8278270c7a19f1a  gnulib-20260109.bundle

XMv72pyPrDiGrukOrQ9UwgLh+bbekQhQWuyaEmEf3Co=  gnulib-20250303.bundle
c3X/89WHMIRVqGpOHHQPZfw2bcxnZEIkgOam7WwRUyw=  gnulib-20250729.bundle
6kYv60oHv7kXpkJM2vUlADWNmh62nus1xA80bJJiJEs=  gnulib-20260109.bundle

Verify the SHA256 checksum with either sha256sum, sha256, or shasum -a 256.

Verify the base64 SHA3-256 checksum with cksum -a sha3 -l 256 --base64 from coreutils 9.8 or newer, or with cksum -a sha3 --check from coreutils 9.9 or newer.

Next to the Git Bundle is a GnuPG signature on the file, named gnulib-YYYYMMDD.bundle.sig, which can be verified using GnuPG as usual: 

gpg --verify gnulib-20260109.bundle.sig

Or using the simpler gpgv tool like this: 

gpgv gnulib-20260109.bundle.sig gnulib-20260109.bundle

The following GnuPG keys have signed releases: 

sec>  ed25519 2019-03-20 [SC] https://josefsson.org/key-20190320.txt
      B1D2BD1375BECB784CF4F8C4D73CF638C53C06BE
uid           [ultimate] Simon Josefsson <simon@josefsson.org>

We desire that the Gnulib Git bundles will be forever bit-by-bit reproducible for others from the official git repository. Currently gnulib maintainers invoke the following commands to prepare and upload the latest Gnulib git bundle. We appreciate ideas on how to improve these set of commands (or the upstream Git tool) to make further supply-chain security related improvements. 

cd $(mktemp -d)
REV=2961ed7a687c11aebdf5951d5267dec85d9e59cb   # master branch commit to package
S1REV=e93789db7e86c51d6cb9683ea508e676a55cdefa # stable-202601 branch commit
S2REV=b6d56475ad6d8bc59e85cdf7fa8dd60fbddc6ffc # stable-202507 branch commit
git clone https://git.savannah.gnu.org/git/gnulib.git
cd gnulib
git fsck # attempt to validate input
# Manually inspect that the new tree matches a trusted previous copy
git checkout -B master $REV # put $REV at master
# Add all stable-* branches locally:
for b in $(git branch -r | grep origin/stable- | sort --version-sort); do git checkout ${b#origin/}; done
git checkout -B stable-202501 $S1REV
git checkout -B stable-202507 $S2REV
git remote remove origin # drop some unrelated branches
git gc --prune=now # drop any unrelated commits, not clear this helps
git -c pack.threads=1 repack -adF
git -c 'pack.threads=1' bundle create gnulib.bundle --all
V=$(env TZ=UTC0 git show -s --date=format:%Y%m%d --pretty=%cd master)
mv gnulib.bundle gnulib-$V.bundle
build-aux/gnupload --to ftp.gnu.org:gnulib gnulib-$V.bundle

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

7 Building the ISO C and POSIX Substitutes

This section shows a radically different way to use Gnulib.

You can extract the ISO C / POSIX substitutes part of gnulib by running the command 

gnulib-tool --create-testdir --source-base=lib \
            --dir=/tmp/posixlib `posix-modules`

The command ‘posix-modules’ is found in the same directory as gnulib-tool.

The resulting directory can be built on a particular platform, independently of the program being ported. Then you can configure and build any program, by setting CPPFLAGS and LDFLAGS at configure time accordingly: set CPPFLAGS="-I.../posixlib/lib", plus any essential type definitions and flags that you find in .../posixlib/config.h, and set LDFLAGS=".../posixlib/lib/libgnu.a".

This way of using Gnulib is useful when you don’t want to modify the program’s source code, or when the program uses a mix between C and C++ sources (requiring separate builds of the posixlib for the C compiler and for the C++ compiler).

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

8 ISO C Keyword Substitutes

This chapter describes which keywords specified by ISO C are substituted by Gnulib.

Next: , Up: ISO C Keyword Substitutes   [Contents][Index]

8.1 alignof and alignas

Gnulib module: alignasof

The alignasof module arranges for alignas and alignof to be more like standard C.

Portability problems fixed by Gnulib:

  • On pre-C23 platforms, <stdalign.h> must be included before using alignas or alignof. See stdalign.h.

Portability problems not fixed by Gnulib:

  • The set of alignments supported by alignas is implementation dependent, and implementations need not support alignments greater than alignof (max_align_t).
  • Some older platforms do not support alignas. To test this, use the alignasof module along with the #if conditional (defined alignas || defined __alignas_is_defined || 202311 <= __STDC_VERSION__ || 201103 <= __cplusplus). Platforms where alignas does not work include: IBM XL C for AIX V16.1.
  • On some platforms, the argument of alignas must be an integer constant like ‘8’, instead of an integer constant expression like ‘4 + 4’ that evaluates to 8: GCC 4.9.
  • On pre-C23 platforms, alignas and alignof are macros.

Next: , Previous: , Up: ISO C Keyword Substitutes   [Contents][Index]

8.2 bool

Gnulib module: bool

Portability problems fixed by Gnulib:

  • The keywords bool, true, and false are not available: gcc 12 and other compilers predating C23.

Portability problems not fixed by Gnulib:

  • On pre-C23 platforms, the keyword substitutes are macros.
  • On pre-C23 platforms, the keyword substitutes assume C99 or later.

Next: , Previous: , Up: ISO C Keyword Substitutes   [Contents][Index]

8.3 nullptr

Gnulib module: nullptr

The nullptr module arranges for nullptr to act like standard C and C++.

The nullptr keyword yields a null pointer. It differs from the NULL macro, in that NULL might be an integer whereas nullptr is of a special nullptr_t type with only one value, namely nullptr itself. Using nullptr can help some compilers emit more sensible warnings, can avoid the need to cast a null pointer passed to a function prototyped with an ellipsis, and removes the need to include <stddef.h> merely to define NULL.

Portability problems fixed by Gnulib:

  • Some platforms lack nullptr: For C: GCC 12, Clang 15, and other pre-2023 C compilers. For C++: pre-2011 C++ compilers.
  • Some platforms incorrectly warn when nullptr is a sentinel argument: GCC 13.2 and 14.0.

Portability problems not fixed by Gnulib:

  • On older platforms, nullptr is a macro instead of a keyword.
  • On older platforms, nullptr does not have the type nullptr_t. In C, it has type void *; in C++ it has an integer type.
  • On older platforms Gnulib cannot easily emulate nullptr_t, so null pointer type checking is more error prone. In C, _Generic expressions cannot reliably distinguish the type of nullptr from integer or void * types. C++ overloading has similar limitations.
  • GCC 14 defines nullptr_t even when <stddef.h> is not included. This bug is fixed in GCC 15.

Previous: , Up: ISO C Keyword Substitutes   [Contents][Index]

8.4 static_assert

Gnulib module: assert-h

The assert-h module arranges for both static_assert and <assert.h> to be like standard C. See assert.h.

Portability problems fixed by Gnulib:

  • Pre-C11 platforms lack static_assert.
  • On pre-C23 platforms, <assert.h> must be included before using static_assert.

Portability problems not fixed by Gnulib:

  • On pre-C23 platforms, static_assert is a macro.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

9 ISO C and POSIX Header File Substitutes

This chapter describes which header files specified by ISO C or POSIX are substituted by Gnulib, which portability pitfalls are fixed by Gnulib, and which (known) portability problems are not worked around by Gnulib.

The notation “Gnulib module: —” means that Gnulib does not provide a module providing a substitute for the header file. When the list “Portability problems not fixed by Gnulib” is empty, such a module is not needed: No portability problems are known. Otherwise, it indicates that such a module would be useful but is not available: No one so far found this header file important enough to contribute a substitute for it. If you need this particular header file, you may write to <bug-gnulib at gnu dot org>.

Next: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.1 aio.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/aio.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.10.x, mingw, MSVC 14, Haiku, Android 9.0.
  • The type off64_t is not defined on some platforms: macOS 14, FreeBSD 10.4, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.2 arpa/inet.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/arpa_inet.h.html

Gnulib module: arpa_inet-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the headers <inttypes.h> and <netinet/in.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.3 assert.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/assert.h.html

Gnulib module: assert-h

See also the Gnulib modules assert and verify.

Portability problems fixed by Gnulib:

  • On older C platforms <assert.h> must be included before using static_assert. For example, GCC versions before 13 do not support the static_assert keyword that was standardized by C23.
  • On older platforms static_assert does not allow the second string-literal argument to be omitted. For example, GCC versions before 9.1 do not support the single-argument static_assert that was standardized by C23 and C++17.
  • Even-older platforms do not support static_assert at all. For example, GCC versions before 4.6 and G++ versions before 4.3 do not support the two-argument form, which was standardized by C11 and C++11.
  • Older C platforms might not support the obsolescent _Static_assert keyword or macro. This portability problem should not matter with code using this module, as such code should use static_assert instead.

Portability problems not fixed by Gnulib:

  • A static_assert can also be used within a struct or union specifier, in place of an ordinary declaration of a member of the struct or union. The Gnulib substitute can be used only as an ordinary declaration in code intended to be portable to C99 or earlier.
  • In C23 and C++11 and later, static_assert is a keyword. In C11 and C17 it is a macro. Any Gnulib substitute is also a macro.
  • In C99 and later, the argument to assert can be of any scalar type. In C89, the argument is of type int.
  • In C23 and C++26 and later, assert is a variadic macro that can be applied to any scalar expression even if it has an unparenthesized comma. In earlier standards, assert is a single-argument macro so its argument cannot contain an unparenthesized comma.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.4 complex.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/complex.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.5 cpio.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/cpio.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: Minix 3.1.8, Cygwin 2.4.x, mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.6 ctype.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/ctype.h.html

Gnulib module: ctype-h

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.7 devctl.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/devctl.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on many platforms: glibc 2.42, macOS 14, FreeBSD 9.3, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.6.0, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.8 dirent.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/dirent.h.html

Gnulib module: dirent-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: MSVC 14.
  • Although many systems define directory entry type macros like DT_DIR, some do not: Minix 3.1.8, AIX 7.2, HP-UX 11, Solaris 11.4, mingw.
  • The directory entry type macro DT_WHT is missing on many systems: All systems where DT_DIR is missing, plus OpenBSD 7.9.
  • The conversion macros DTTOIF and IFTODT are missing on many systems (however, the Gnulib replacement macros may evaluate their arguments multiple times): All systems where DT_DIR is missing, plus OpenBSD 7.9.
  • The type ino_t is missing on some platforms: glibc 2.23 and others.

Portability problems not fixed by Gnulib:

  • Although many systems define a struct dirent member named d_type, some do not: Minix 3.1.8, AIX 7.2, HP-UX 11, Solaris 11.4, mingw.
  • On systems with d_type, not every filesystem supports d_type, and those lacking support will set it to DT_UNKNOWN.
  • The POSIX.1-2024 directory entry type macros DT_MQ, DT_SEM, DT_SHM and DT_TMO are missing on many platforms.
  • Some systems define a struct dirent member named d_namlen containing the string length of d_name, but others do not: glibc 2.23 on Linux, Minix 3.1.8, Solaris 11.4, Cygwin. All of these, except Cygwin, have a member d_reclen instead, that has a different semantics.
  • Some systems define a struct dirent member named d_off containing a magic cookie suitable as an argument to seekdir, but others do not: glibc 2.23 on Hurd, macOS 11.1, FreeBSD 11.0, NetBSD 10.0, OpenBSD 7.9, AIX 5.1, HP-UX 11, Cygwin, mingw.
  • Some systems define a struct dirent member named d_reclen containing the number of bytes in the directory entry record, but others do not. This member has limited utility, as it is an implementation detail.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.9 dlfcn.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/dlfcn.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.10 endian.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/endian.h.html

Describes the platform’s endianness (byte ordering of words stored in memory). Defines the macros BYTE_ORDER, LITTLE_ENDIAN, BIG_ENDIAN, PDP_ENDIAN.

Gnulib module: endian

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: macOS 14, FreeBSD 13.0, NetBSD 7.1, OpenBSD 3.8, Minix 3.1.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the header <stdint.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.11 errno.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/errno.h.html

Gnulib module: errno-h

Portability problems fixed by Gnulib:

  • The macro EOVERFLOW is not defined on some platforms: OpenBSD 4.0, mingw, MSVC 9.
  • The macro ENOLINK is not defined on some platforms: OpenBSD 7.9, mingw, MSVC 9.
  • The macro EMULTIHOP is not defined on some platforms: OpenBSD 7.9, mingw, MSVC 14.
  • The macro ECANCELED is not defined on some platforms: OpenBSD 4.0, Cygwin, mingw, MSVC 9.
  • The macros ENOMSG, EIDRM, EPROTO, EBADMSG, ENOTSUP are not defined on some platforms: OpenBSD 4.0, mingw, MSVC 9.
  • The macro ESTALE is not defined on some platforms: mingw, MSVC 14.
  • The macro EDQUOT is not defined on some platforms: NonStop Kernel, mingw, MSVC 14.
  • The macros ENETRESET, ECONNABORTED are not defined on some platforms: Minix 3.1.8, mingw, MSVC 9.
  • The macros EWOULDBLOCK, ETXTBSY, ELOOP, ENOTSOCK, EDESTADDRREQ, EMSGSIZE, EPROTOTYPE, ENOPROTOOPT, EPROTONOSUPPORT, EOPNOTSUPP, EAFNOSUPPORT, EADDRINUSE, EADDRNOTAVAIL, ENETDOWN, ENETUNREACH, ECONNRESET, ENOBUFS, EISCONN, ENOTCONN, ETIMEDOUT, ECONNREFUSED, EHOSTUNREACH, EALREADY, EINPROGRESS are not defined on some platforms: mingw, MSVC 9.
  • The macros EOWNERDEAD, ENOTRECOVERABLE are not defined on some platforms: glibc/Linux 2.3.6, glibc/Hurd 2.15, glibc/kFreeBSD 2.15, Mac OS X 10.5, FreeBSD 6.0, NetBSD 9.3, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin, mingw without pthreads-win32, MSVC 9.
  • The macro ESOCKTNOSUPPORT is not defined on some platforms: Haiku.
  • The macro EILSEQ is not defined on some platforms: LynxOS 178 2.2.2.
  • The macros EEXIST and ENOTEMPTY have the same value on some platforms: AIX 7.3.

Portability problems not fixed by Gnulib:

  • Error numbers are in the range INT_MIN through INT_MIN + 0xffff, instead of being positive as POSIX requires: Haiku.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.12 fcntl.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/fcntl.h.html

Gnulib module: fcntl-h

Portability problems fixed by Gnulib:

  • The type pid_t is not defined on some platforms: MSVC 14.
  • The type mode_t is not defined on some platforms: MSVC 14.
  • The type off64_t is not defined on some platforms: macOS 14, FreeBSD 10.4, NetBSD 10.0, OpenBSD 7.9, MSVC 14, Cygwin, Haiku, Minix 3.3.
  • ‘O_CLOEXEC’ is not defined on some platforms: Mac OS X 10.6, FreeBSD 8.4, NetBSD 5.1, OpenBSD 4.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 10, Cygwin 1.7.1, mingw, MSVC 14.
  • ‘O_DSYNC’, ‘O_NOCTTY’, ‘O_NOFOLLOW’, ‘O_RSYNC’, ‘O_SYNC’, and ‘O_TTY_INIT’ are not defined on some platforms. When not otherwise defined, Gnulib defines these macros to 0, which is generally safe.
  • ‘O_NONBLOCK’ is not defined on some platforms. If the ‘nonblocking’ module is in use, gnulib guarantees a working non-zero value; otherwise, the gnulib replacement is 0.
  • ‘O_EXEC’ is not defined on some platforms: glibc 2.42, macOS 12, FreeBSD 7.4, NetBSD 9.4, OpenBSD 7.9, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android. However, glibc does define ‘O_EXEC’ on GNU/Hurd. When not otherwise defined, Gnulib defines this macro to ‘O_RDONLY’, which is typically 0.

    Note: ‘O_EXEC’ is not suitable for opening a file descriptor that you want to use with fchmod later, because musl libc defines ‘O_EXEC’ to O_PATH and Linux fchmod fails with error EBADF when given such a file descriptor.

  • ‘O_SEARCH’ is not defined on some platforms: glibc 2.42, macOS 12, FreeBSD 12.4, NetBSD 6.1, OpenBSD 7.9, AIX 6.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android. When not otherwise defined, Gnulib defines this macro to ‘O_RDONLY’, which is typically 0.
  • ‘O_SEARCH’ is defined to O_PATH on some platforms: musl libc.
  • ‘O_ACCMODE’ is not defined on some platforms: MSVC 14.
  • The ‘O_ACCMODE’ mask mistakenly omits ‘O_SEARCH’ and ‘O_EXEC’ on some platforms: Cygwin.
  • ‘O_BINARY’, ‘O_TEXT’ (not specified by POSIX, but essential for portability to native Windows platforms) are defined on some platforms but not on others. Gnulib defines these macros to 0 on GNU and other platforms that do not distinguish between text and binary I/O.
  • ‘O_CLOEXEC’, ‘O_NOFOLLOW’, and ‘O_TTY_INIT’ are defined to values that are too large for an int on some platforms: AIX 7.1 with XL C 12.1.
  • ‘O_DIRECT’, ‘O_IGNORE_CTTY’, ‘O_NDELAY’, ‘O_NOATIME’, ‘O_NOLINK’, ‘O_NOLINKS’, and ‘O_NOTRANS’ (not specified by POSIX) are defined on some platforms but not on others. When not otherwise defined, Gnulib defines these macros to 0, which is generally safe.
  • ‘O_DIRECTORY’ is not defined on some platforms: glibc 2.0, Mac OS X 10.4, FreeBSD 7.4, NetBSD 4.0.1, OpenBSD 4.9, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14.
  • ‘FD_CLOEXEC’, ‘F_DUPFD’, and ‘F_GETFD’ are not defined on some platforms: mingw, MSVC 14.
  • ‘F_DUPFD_CLOEXEC’ is not defined on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, AIX 5.1, HP-UX 11, Solaris 11 2010-11, Cygwin 1.7.1, mingw, MSVC 14.
  • ‘AT_FDCWD’, ‘AT_EACCESS’, ‘AT_SYMLINK_NOFOLLOW’, ‘AT_SYMLINK_FOLLOW’, and ‘AT_REMOVEDIR’ are not defined on many platforms: glibc 2.3.6, Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, AIX 5.1, HP-UX 11, Cygwin 1.5.x, mingw, MSVC 14.
  • ‘AT_FDCWD’ is defined with a value too large for an int on some platforms: Solaris 11.3.

Portability problems not fixed by Gnulib:

  • On some platforms, ‘O_NOATIME’ and ‘O_NOFOLLOW’ are defined but do not work. To help work around the resulting portability problems, the fcntl-h module defines ‘HAVE_WORKING_O_NOATIME’ to 1 on platforms where ‘O_NOATIME’ is known to work, and to 0 otherwise; and similarly for ‘HAVE_WORKING_O_NOFOLLOW’ and ‘O_NOFOLLOW’: Mac OS X 10.3.
  • ‘O_PATH’ and ‘AT_EMPTY_PATH’ are not defined on some platforms: glibc 2.13, macOS 26, FreeBSD 13.0, NetBSD 10.1, OpenBSD 7.9, Minix 3.3.0, AIX 7.3, HP-UX 11.31, Solaris 11.4, Cygwin 3.0, mingw, MSVC 14.
  • Although POSIX.1-2024 standardized O_CLOFORK, FD_CLOFORK and F_DUPFD_CLOFORK, they are not defined on most platforms: glibc 2.42, musl libc, macOS 15.5, FreeBSD 14.2, NetBSD 10.1, OpenBSD 7.7, Minix 3.3.0, AIX 7.3, Solaris 11.3, Cygwin 3.6.2, mingw, MSVC 14.
  • ‘F_SETFD’, ‘F_GETFL’, ‘F_SETFL’, ‘F_GETLK’, ‘F_SETLK’, ‘F_SETLKW’, ‘F_GETOWN’, and ‘F_SETOWN’ are not defined on some platforms: mingw, MSVC 14.
  • ‘POSIX_FADV_DONTNEED’, ‘POSIX_FADV_NOREUSE’, ‘POSIX_FADV_NORMAL’, ‘POSIX_FADV_RANDOM’, ‘POSIX_FADV_SEQUENTIAL’, and ‘POSIX_FADV_WILLNEED’ are not defined on some platforms.
  • POSIX allows ‘AT_FDCWD’ to be −1, so it is unsafe to use ‘AT_FDCWD’ as an invalid directory file descriptor argument to functions like ‘openat’. Instead, you can use ‘AT_FDCWD == -1 ? -2 : -1’. ‘AT_FDCWD’ is −1 on some platforms: Haiku R1/Beta4.
  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the headers <sys/stat.h> and <unistd.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.13 fenv.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/fenv.h.html

Gnulib module: fenv-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, AIX 5.1, Cygwin 1.7.7, MSVC 9.

Portability problems not fixed by Gnulib:

  • On MSVC, the values of the rounding direction macros have changed: In MSVC 14, FE_UPWARD is 0x100 and FE_DOWNWARD is 0x200, whereas in MSVC 14.30, it’s the opposite.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.14 float.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/float.h.html

Gnulib module: float-h

Portability problems fixed by Gnulib:

  • The conversion from int to long double in incorrect on some platforms: glibc 2.7 on Linux/SPARC64.
  • The values of LDBL_* macros are incorrect on some platforms: On OpenBSD 4.0 and MirBSD 10, they are the same as the values of the DBL_* macros, although ‘long double’ is a larger type than ‘double’. On FreeBSD/x86 6.4, they represent the incorrect 53-bit precision assumptions in the compiler, not the real 64-bit precision at runtime. On PowerPC with gcc 8.3 and the default -mabi=ibmlongdouble, they don’t reflect the “double double” representation of long double correctly; the non-IEEE representation is tricky, as it is a pair of IEEE double values such that adding the two elements and rounding to even yields the high element of the pair, and arithmetic overflow has undefined behavior instead of reliably yielding infinity.
  • The macros FLT_HAS_SUBNORM, FLT_DECIMAL_DIG, FLT_TRUE_MIN, DBL_HAS_SUBNORM, DBL_DECIMAL_DIG, DBL_TRUE_MIN, LDBL_HAS_SUBNORM, LDBL_DECIMAL_DIG, LDBL_TRUE_MIN, that were added in ISO C 11, are missing on some platforms: gcc 4.5.4, clang 7, Solaris 11.3 with Sun C.
  • The macro LDBL_DECIMAL_DIG is missing on some platforms: MSVC 14.
  • The value of macro FLT_TRUE_MIN is not a float on some platforms: AIX 7.1 with xlc.
  • The macros FLT_IS_IEC_60559, FLT_NORM_MAX, FLT_SNAN, DBL_IS_IEC_60559, DBL_NORM_MAX, DBL_SNAN, LDBL_IS_IEC_60559, LDBL_NORM_MAX, LDBL_SNAN, that were added in ISO C 23, are missing on some platforms: gcc 14 without -std=c23 or -std=gnu23, clang 18, musl libc 1.2.5, AIX 7.3 with xlclang, Solaris 11.3 with Sun C, MSVC 14.

Portability problems not fixed by Gnulib:

  • The macro FLT_ROUNDS is a constant expression and does not represent the current rounding mode on some platforms: glibc 2.11, HP-UX 11, mingw.
  • The value of FLT_TRUE_MIN is not a constant on some platforms: FreeBSD/x86.
  • The values of FLT_SNAN, DBL_SNAN, LDBL_SNAN are not constants on some platforms: AIX 7.3 with xlclang, and all platforms which use the gnulib replacements.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.15 fmtmsg.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/fmtmsg.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, Cygwin, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.16 fnmatch.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/fnmatch.h.html

Gnulib module: fnmatch-h, fnmatch-gnu

Portability problems fixed by Gnulib module fnmatch-h:

  • This header file is missing on some platforms: mingw, MSVC 14.

Portability problems fixed by Gnulib module fnmatch-gnu, together with module fnmatch-h:

  • The macros FNM_LEADING_DIR and FNM_CASEFOLD are not defined on some platforms: AIX 7.2, HP-UX 11.31, Solaris 10.
  • The macro FNM_EXTMATCH is not defined on all non-glibc platforms: musl libc, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.2, Minix 3.3, AIX 7.2, HP-UX 11.31, Solaris 11.4, Cygwin 3.4.6, Android 13.
  • The macro FNM_FILE_NAME is not defined on some platforms: NetBSD 10.0, AIX 7.2, HP-UX 11.31, Solaris 10.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.17 ftw.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/ftw.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: FreeBSD 5.2.1, NetBSD 3.0, Minix 3.1.8, mingw, MSVC 14.
  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the header <sys/stat.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.18 glob.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/glob.h.html

Gnulib module: glob-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.19 grp.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/grp.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.20 iconv.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/iconv.h.html

Gnulib module: iconv

Portability problems fixed by Gnulib:

  • The <iconv.h> from GNU libiconv is not found if installed in $PREFIX/include.

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: FreeBSD 6.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14, when GNU libiconv is not installed.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.21 inttypes.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/inttypes.h.html

Gnulib module: inttypes-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: MSVC 9.
  • This header file is very incomplete on some platforms.
  • The declarations of imaxabs and imaxdiv are missing on some platforms: NetBSD 3.0, OpenBSD 3.8, AIX 5.1, HP-UX 11.
  • The declarations of strtoimax and strtoumax are missing on some platforms: OpenBSD 3.8, AIX 5.1 (missing only strtoumax).
  • On some hosts that predate C++11, when using C++ one must define __STDC_FORMAT_MACROS to make visible the declarations of format macros such as PRIdMAX.

Portability problems not fixed by Gnulib:

  • The macros SCN*8, SCN*LEAST8, SCN*FAST8 are missing on some platforms: mingw without __USE_MINGW_ANSI_STDIO.
  • The macros PRIb*, PRIB*, SCNb*, that were added in ISO C 23, are missing on many platforms: glibc 2.37 and many others.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.22 iso646.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/iso646.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: Minix 3.1.8, HP-UX 11.00, Cygwin, mingw.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.23 langinfo.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/langinfo.h.html

Gnulib module: langinfo-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • The constant CODESET is not defined on some platforms: OpenBSD 3.8.
  • The constants ALTMON_1 to ALTMON_12 are not defined on some platforms: glibc 2.26, musl libc, macOS 11.1, NetBSD 8.0, OpenBSD 7.9, AIX 7.2, HP-UX 11.31, Solaris 11.4, Haiku, Cygwin 2.9.
  • The constants ABALTMON_1 to ABALTMON_12 are not defined on many platforms: glibc 2.42, musl libc, macOS 14, NetBSD 10.0, OpenBSD 7.6, AIX 7.3, HP-UX 11.31, Solaris 11.4, Haiku, Cygwin 3.5.
  • The constants ERA, ERA_D_FMT, ERA_D_T_FMT, ERA_T_FMT, ALT_DIGITS are not defined on some platforms: OpenBSD 7.9.

Portability problems not fixed by Gnulib:

  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the header <nl_types.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.24 libgen.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/libgen.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.

The Gnulib module dirname provides similar API, with functions base_name and dir_name that also work with Windows file names.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.25 libintl.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/libintl.h.html

Defines the macros __USE_GNU_GETTEXT, __GNU_GETTEXT_SUPPORTED_REVISION, and declares the functions gettext, dgettext, dcgettext, ngettext, dngettext, dcngettext, textdomain, bindtextdomain, bind_textdomain_codeset.

Documentation:

Gnulib module: gettext

Portability problems fixed by Gnulib, if GNU gettext is installed:

  • This header file is missing on some platforms: macOS 14, FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14, Android 9.0.
  • The functions cannot deal with GNU .mo files with system-dependent strings (of major version 1 or of minor version 1) on some non-glibc platforms: NetBSD 3.0, Solaris 10.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.26 limits.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/limits.h.html

Gnulib module: limits-h or gethostname

Portability problems fixed by Gnulib module limits-h:

  • The macros LLONG_MIN, LLONG_MAX, ULLONG_MAX are not defined on some platforms: older glibc systems (e.g. Fedora 1), AIX 5.1, HP-UX 11, OpenVMS.
  • The macro MB_LEN_MAX is not defined on some platforms: pcc 1.2.0.DEVEL 20220331.
  • The macros WORD_BIT, LONG_BIT are not defined on some platforms: glibc 2.11 without -D_GNU_SOURCE, Cygwin, mingw, MSVC 14.
  • Macros like CHAR_WIDTH are not defined on some platforms: glibc 2.24, NetBSD 10.0, many others.
  • The macros BOOL_MAX and BOOL_WIDTH are not defined on some platforms: glibc 2.32, many others.
  • The macro BOOL_MAX is not defined with some compilers: clang 15.0.6.
  • The macro SSIZE_MAX is not defined on some platforms: MSVC 14.

Portability problems fixed by Gnulib module gethostname:

  • The HOST_NAME_MAX macro is not defined on some platforms: macOS 11.1, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • The macro SSIZE_MAX has the wrong type, albeit with the correct value: 32-bit glibc 2.24 (on some architectures), Cygwin 2.5.2.

For PATH_MAX, Gnulib provides a module pathmax with a header file "pathmax.h". It defines PATH_MAX to a constant on platforms with a file name length limit.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.27 locale.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/locale.h.html

Gnulib module: locale-h

Portability problems fixed by Gnulib:

  • The definition of ‘LC_MESSAGES’ is missing on some platforms: mingw, MSVC 14.
  • The locale_t type is not defined on some platforms: glibc 2.11, macOS 11.1, FreeBSD 9.0, NetBSD 6.1, OpenBSD 6.1, Solaris 11.3, mingw, MSVC 14, Android 4.4.
  • The struct lconv type does not contain any members on some platforms: Android up to 2014.
  • The struct lconv type does not contain the members int_p_cs_precedes, int_p_sign_posn, int_p_sep_by_space, int_n_cs_precedes, int_n_sign_posn, int_n_sep_by_space on some platforms: glibc, OpenBSD 4.9, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14.
  • Some platforms provide a NULL macro that cannot be used in arbitrary expressions: NetBSD 5.0

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.28 math.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/math.h.html

Gnulib module: math-h

Portability problems fixed by Gnulib:

  • The conversion from int to long double in incorrect on some platforms: glibc 2.7 on Linux/SPARC64.
  • The macro NAN is not defined on some platforms: OpenBSD 4.0, AIX 5.1.
  • The macro NAN is not exposed outside of C99 compilation on some platforms: glibc.
  • The macros NAN and HUGE_VAL expand to a function address rather than a floating point constant on some platforms: Solaris 10.
  • The macros HUGE_VALF and HUGE_VALL are not defined on some platforms: glibc/HPPA, glibc/SPARC, AIX 5.1, Solaris 9, MSVC 9.
  • The macros FP_ILOGB0 and FP_ILOGBNAN are not defined on some platforms: NetBSD 5.1, AIX 5.1, Solaris 9, MSVC 9.
  • HUGE_VAL, HUGE_VALF, HUGE_VALL are not compile time constants on some platforms: FreeBSD 5.2, AIX 7.1.
  • INFINITY and NAN are not compile time constants on some platforms: FreeBSD 5.2, AIX 7.1.
  • INFINITY and NAN are of type double instead of float on some platforms: FreeBSD 7.1, mingw 5.0.
  • The macros NAN, HUGE_VALL, and INFINITY are not defined on some platforms: OpenVMS.

Portability problems not fixed by Gnulib:

  • NAN is not a compile time constant with some compilers: OpenVMS.
  • The macro or variable math_errhandling is not defined on some platforms: glibc 2.11, OpenBSD 4.9, NetBSD 5.1, UP-UX 11, Cygwin 1.7.9, mingw, MSVC 9.
  • The macros FP_ILOGB0 and FP_ILOGBNAN have wrong values on some platforms: Haiku before 2023-04-08.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.29 monetary.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/monetary.h.html

Gnulib module: monetary-h

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 1.7.1, mingw, MSVC 14, Android 9.0.
  • This header file has a syntax error in C++ mode on some platforms: NetBSD 8.0.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.30 mqueue.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/mqueue.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.31 ndbm.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/ndbm.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: Cygwin 3.0.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.32 net/if.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/net_if.h.html

Gnulib module: net_if-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.
  • This header file is not self-contained on some platforms (needing <sys/socket.h> to be included first): Mac OS X 10.5, FreeBSD 8.2, OpenBSD 5.2.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.33 netdb.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/netdb.h.html

Gnulib module: netdb-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.
  • This header file is incomplete on some platforms: Cygwin 1.5.x, Haiku.
  • This header file does not define AI_ALL, AI_V4MAPPED on some platforms: NetBSD 10.0.
  • This header file does not define AI_ADDRCONFIG on some platforms: NetBSD 5.0.
  • This header file does not define AI_NUMERICHOST on some platforms: HP-UX 11.11.
  • This header file does not define AI_NUMERICSERV on some platforms: macOS 10.5, HP-UX 11.11, mingw.
  • This header file incorrectly defines NI_MAXHOST on some platforms: musl libc 1.2.4, OpenBSD 7.9.

Portability problems not fixed by Gnulib:

  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the headers <inttypes.h>, <netnet/in.h>, and <sys/socket.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.34 netinet/in.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/netinet_in.h.html

Gnulib module: netinet_in-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.
  • This header file is not self-contained on some platforms (it requires <sys/types.h> to be included first): OpenBSD 4.6.

Portability problems not fixed by Gnulib:

  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the headers <arpa/inet.h>, <inttypes.h> and <sys/socket.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.35 netinet/tcp.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/netinet_tcp.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.36 nl_types.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/nl_types.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: Minix 3.1.8, Cygwin 2.9.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.37 poll.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/poll.h.html

Gnulib module: poll-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the headers <signal.h> and <time.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.38 pthread.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/pthread.h.html

Gnulib module: pthread-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms. Minix 3.1.8, mingw 2.x, MSVC 14. But the provided replacement covers only the essential POSIX threads API. Furthermore it is just a dummy on some of these platforms: Minix 3.1.8.
  • This header pollutes the namespace with some broken macro implementations for various functions such as strtok_r and gmtime_r: mingw 3.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.39 pwd.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/pwd.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.40 regex.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/regex.h.html

Gnulib module: regex

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.
  • On some systems that have this header file, GNU extensions like re_set_syntax and RE_SYNTAX_EMACS are not declared or supported: FreeBSD 14.2, OpenBSD 7.6, NetBSD 10.1, macOS 15, Minix 3.3.0, AIX 7.3, HP-UX 11, Solaris 11.4.
  • On some systems that support GNU extensions, RE_SYNTAX_EMACS is 0 even though it should be (RE_CHAR_CLASSES | RE_INTERVALS) to be compatible with Emacs 21 (2001) and later: glibc 2.42, Cygwin 2.6.x.

Portability problems not fixed by Gnulib:

  • This header file is not self-contained on some platforms: it requires <sys/types.h> to be included first.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.41 sched.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sched.h.html

Gnulib module: sched-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • This header file does not define the type pid_t on some platforms: glibc 2.11, macOS 11.1.
  • struct sched_param is not defined on some platforms: Haiku.
  • SCHED_FIFO, SCHED_RR, SCHED_OTHER are not defined on some platforms: Haiku.

Portability problems not fixed by Gnulib:

  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the header <time.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.42 search.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/search.h.html

Gnulib module: search-h

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: Minix 3.1.8.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.43 semaphore.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/semaphore.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.44 setjmp.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/setjmp.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.45 signal.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/signal.h.html

Gnulib module: signal-h

Portability problems fixed by Gnulib:

  • volatile sig_atomic_t is rejected by older compilers on some platforms: AIX.
  • sigset_t is missing on some platforms: MSVC 14.
  • sigset_t is only declared in <sys/types.h> on some platforms: mingw.
  • struct sigaction and siginfo_t are missing on some platforms: mingw, MSVC 14.
  • The type pid_t is not defined on some platforms: MSVC 14.
  • The signal SIGPIPE is not defined on some platforms: mingw, MSVC 14.
  • The macros SA_RESETHAND and SA_RESTART are not defined on some platforms: NonStop.
  • The type sighandler_t (a GNU extension) is not defined on most non-glibc platforms: macOS 11.1, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • Many signals are not defined on some platforms: mingw, MSVC 14.
  • The macro SIGBUS is set to the same value as SIGSEGV, rather than being a distinct signal, on some platforms: Haiku.
  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the header <time.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.46 spawn.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/spawn.h.html

Gnulib module: spawn-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.7.25, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.47 stdalign.h

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf sections 6.5.3.4, 6.7.5, 7.15.

C++11 specification:
https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2011/n3242.pdf section 18.10.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/stdalign.h.html

Gnulib module: alignasof

Portability problems fixed by Gnulib:

  • On older C platforms <stdalign.h> must be included before using alignas or alignof. For example, GCC versions before 13 do not support these keywords, which were standardized by C23. On C23 and later platforms, <stdalign.h> has no effect and need not be included. (Gnulib-using code should not include <stdalign.h> without also employing Gnulib’s now-deprecated stdalign-h module.)
  • This header file is missing on many platforms: FreeBSD 6.4, NetBSD 7.1, OpenBSD 7.9, Minix 3.3.0, AIX 7.1, HP-UX 11.31, Solaris 11.3, mingw, MSVC 14, Android 9.0.
  • Clang 3.0’s <stdalign.h> does not define alignof.
  • The alignof macro returns too large values for the types double and long long in GCC 4.7.0.
  • Older C platforms might not support the obsolescent _Alignas and _Alignof keywords or macros. This portability problem should not matter with code using this module, as such code should use alignas and alignof instead.
  • In C11 and C17, <stdalign.h> defines the macros __alignas_is_defined and __alignof_is_defined to 1. In C23, these macros are not defined. This portability problem should not matter with code using Gnulib’s alignasof module, as such code should use alignas and alignof without checking these two macros. (Gnulib’s now-deprecated stdalign-h module defines these two macros.)
  • Clang 17 does not support an alignas attribute in the specifier-qualifier position of a member declaration.

Portability problems not fixed by Gnulib:

  • In C11 and later, the operand of alignof must be a parenthesized type. Recent versions of GCC support an extension in which the operand can also be a unary expression, as with sizeof. The Gnulib substitute does not support this extension.
  • On most pre-C11 platforms, the operand of alignof cannot be a structure type containing a flexible array member.
  • The alignas keyword or macro is not always supported. Supported compilers include any compiler supporting C11 or later, which includes GCC, IBM C, Sun C 5.9 and later, and MSVC 7.0 and later.
  • Some compilers do not support alignment via alignas of auto variables (i.e., variables on the stack). They diagnose and ignore the alignment: Sun C 5.11.
  • Some linkers do not support operands of alignas that are greater than 8: mingw.
  • Some compilers require the operand of alignas to be a single integer constant, not an expression: MSVC 7.0 through at least 10.0.
  • The Sun C 5.13 (2014) compiler sometimes mishandles the alignment of multiple external variables that are declared close together with alignas. The bug is fixed in Sun C 5.15, also known as Oracle Developer Studio 12.6 (2017).
  • You cannot assume that alignas and alignof are reserved words; they might be macros.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.48 stdarg.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/stdarg.h.html

Gnulib module: stdarg-h

Portability problems fixed by Gnulib:

  • Some compilers (e.g., AIX 5.3 cc) need to be in c99 mode for the builtin va_copy to work.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.49 stdatomic.h

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/stdatomic.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14.
  • Linus Torvalds believes that “no compiler writer will get the C/C++ memory model right”; see https://lkml.org/lkml/2018/6/7/761.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.50 stdbit.h

POSIX :
Not in POSIX yet, but we expect it will be. ISO C23 (latest free draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf) section 7.18.

Gnulib module: stdbit

Portability problems fixed by Gnulib:

  • This header file is missing on many non-C23 platforms: glibc 2.38, macOS 14, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.
  • This header file exists but is a no-op: G++ 15.2.
  • This header file has syntax errors in C++ mode on some platforms: FreeBSD 15.1.
  • This header file does not define the necessary types with the Intel icpx C++ compiler.

Portability problems not fixed by Gnulib:

  • On older non-C23 platforms lacking typeof or equivalent, a call to stdc_bit_floor and stdc_bit_ceil may yield a type that is wider than its argument. Although C23 seems to allow this, it differs from GNU behavior.
  • On non-C23 platforms, type-generic functions apply portably only to the standard unsigned integer types specified by C17 or earlier.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.51 stdbool.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/stdbool.h.html

Gnulib module: stdbool-h-c99

The stdbool-h-c99 module is present only for programs that formerly used the old stdbool module for C99 compatibility, and that for some reason cannot use the current bool module for C23 compatibility.

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: AIX 5.1, HP-UX 11.
  • This header file is not usable in C++ mode with the vendor compiler on Solaris 10.
  • Some compilers have bugs relating to ‘bool’.
  • This header file defines true incorrectly on some platforms: OpenBSD 4.7 with gcc 2.95.

Portability problems not fixed by Gnulib:

  • ‘_Bool’ cannot be used before <stdbool.h> is included, or if the program is intended to be compiled by a C++ compiler. (With the advent of C23, ‘_Bool’ is obsolescent anyway.)
  • You cannot assume that _Bool is a keyword or a typedef; it might be a macro. For example, C23 allows _Bool to be a macro.
  • Bit-fields of type ‘bool’ are not supported. Portable code should use ‘unsigned int foo : 1;’ rather than ‘bool foo : 1;’.
  • Casts and automatic conversions to ‘bool’ don’t test against the zero value or the null pointer, as they should. Such casts should only be used if the value is known to be equal to 0 or 1.
  • You cannot assume that casting a floating point literal to ‘bool’ will result in a constant expression.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.52 stdckdint.h

POSIX specification:
Not in POSIX yet, but we expect it will be. ISO draft C23 (https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf) section 7.20.

Gnulib module: stdckdint-h

Portability problems fixed by Gnulib:

  • This header file is missing on many platforms: glibc 2.29, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9.0, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

  • In draft C23, arguments of stdckdint.h macros can have side effects.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.53 stdcountof.h

POSIX specification:
Not in POSIX yet, but we expect it will be. ISO draft C2y N3783 (https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) § 7.21.

Gnulib module: stdcountof-h

Portability problems fixed by Gnulib:

  • This header file is missing on many platforms: GCC 15, Clang 20, MSVC 14.50, Oracle Developer Studio 12.6, IBM Open XL C for AIX 17.1, TCC 0.9.27.

Portability problems not fixed by Gnulib:

  • On some platforms, arguments of countof are evaluated if they contain designated initializers, e.g., countof ((int[]) {getchar ()}) incorrectly calls getchar. This is because these platforms have a similar bug with sizeof ((int[]) {getchar ()}): MSVC 14.50, Oracle Developer Studio 12.6, IBM XL C for AIX 16.1.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.54 stddef.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/stddef.h.html

Gnulib module: stddef-h

Portability problems fixed by Gnulib:

  • Some platforms fail to provide unreachable, which was added in C23: GCC 13, clang 15, AIX with xlc 12.1, Solaris with Sun C 5.15, and others.
  • Some platforms fail to provide max_align_t, which was added in C11: NetBSD 8.0, Solaris 11.0, and others.
  • max_align_t does not have the expected alignment on some platforms: NetBSD 8.0/x86, AIX 7.2 with xlc in 64-bit mode.
  • Some platforms provide a NULL macro that cannot be used in arbitrary expressions: NetBSD 5.0
  • Some platforms provide a NULL macro whose value does not have the size of a pointer: AIX 7.2 with xlc in 64-bit mode.
  • When this header file is provided by TinyCC 0.9.27 on glibc or macOS systems, it does not fulfil the expectations of other system header files.

Portability problems not fixed by Gnulib:

  • Some platforms fail to provide nullptr_t, which Gnulib cannot usefully emulate: GCC 12, Clang 15, and other pre-2023 C compilers.
  • Some platforms define nullptr_t even when <stddef.h> is not included: GCC 14
  • Some platforms provide an offsetof macro that cannot be used in arbitrary expressions: Solaris 11.4 This problem can be worked around by parenthesizing the offsetof expression in the unlikely case you use it with sizeof or ‘[]’.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.55 stdint.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/stdint.h.html

Gnulib module: stdint-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: OpenBSD 3.8, AIX 5.1, HP-UX 11.11, MSVC 9.
  • This header file is very incomplete on some platforms.
  • The values of SIG_ATOMIC_MIN and SIG_ATOMIC_MAX are incorrect on some platforms: FreeBSD 6.2/ia64, FreeBSD 13.0/arm64.
  • The value of WINT_MAX is incorrect on some platforms: mingw.
  • The values of INT8_MAX, UINT8_MAX etc. are not usable in preprocessor expressions on some platforms: HP-UX 11.23.
  • The values of INTPTR_MAX and UINTPTR_MAX, although correctly defined in <stdint.h>, are replaced by empty values when <limits.h> or <inttypes.h> gets included later on some platforms: Solaris 9 with GCC 4.5 or newer.
  • The macros WCHAR_MIN and WCHAR_MAX are not defined in <stdint.h> (only in <wchar.h>) on some platforms: Dragonfly.
  • On some hosts that predate C++11, when using C++ one must define __STDC_CONSTANT_MACROS to make visible the definitions of constant macros such as INTMAX_C, and one must define __STDC_LIMIT_MACROS to make visible the definitions of limit macros such as INTMAX_MAX.
  • The macro SIZE_MAX has the wrong type, albeit with the correct value: 32-bit glibc 2.24 (on s390 architecture), Mac OS X 10.7.
  • Macros like INTMAX_WIDTH are not defined on some platforms: glibc 2.24, NetBSD 10.0, many others.

Portability problems not fixed by Gnulib:

  • {uint,int}_fast{8,16,32,64}_t may not correspond to the fastest types available on the system. Other <stdint.h> substitutes may define these types differently, so public header files should avoid these types.
  • Macros are used instead of typedefs.
  • Some C preprocessors mishandle constants that do not fit in long int. For example, as of 2007, Sun C mishandled #if LLONG_MIN < 0 on a platform with 32-bit long int and 64-bit long long int; this bug was fixed on or before Oracle Developer Studio 12.6 (Sun C 5.15 SunOS_sparc 2017/05/30). Some older preprocessors mishandle constants ending in LL. To work around these problems, compute the value of expressions like LONG_MAX < LLONG_MAX at configure-time rather than at #if-time.

The stdint-h module uses #include_next. If you wish to install the generated stdint.h file under another name, typically in order to be able to use some of the types defined by stdint.h in your public header file, you could use the following Makefile.am-snippet: 


BUILT_SOURCES += idn-int.h
DISTCLEANFILES += idn-int.h
nodist_include_HEADERS += idn-int.h

idn-int.h:
	if test -n "$(STDINT_H)"; then \
		sed -e s/include_next/include/ gl/stdint.h > idn-int.h; \
	else \
		echo '#include <stdint.h>' > idn-int.h; \
	fi

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.56 stdio.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/stdio.h.html

Gnulib module: stdio-h

Portability problems fixed by Gnulib:

  • The type off_t is not defined on some platforms: glibc 2.8, eglibc 2.11.2 and others.
  • The type ssize_t is not defined on some platforms: glibc 2.8, Mac OS X 10.5, Solaris 10, MSVC 14, and others.
  • The type va_list is not defined on some platforms: glibc 2.8, OpenBSD 4.0, Solaris 11.4, and others.
  • The type off64_t is not defined on some platforms: macOS 14, FreeBSD 10.4, NetBSD 10.0, OpenBSD 7.9, MSVC 14, Cygwin, Haiku, Minix 3.3.
  • Some platforms provide a NULL macro that cannot be used in arbitrary expressions: NetBSD 5.0

Portability problems not fixed by Gnulib:

  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the header <stddef.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.57 stdlib.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/stdlib.h.html

Gnulib module: stdlib-h, system-posix

Portability problems fixed by the Gnulib module stdlib-h:

  • The macros EXIT_SUCCESS and EXIT_FAILURE are not defined on some platforms.
  • Some platforms provide a NULL macro that cannot be used in arbitrary expressions: NetBSD 5.0
  • Using the macro MB_CUR_MAX causes link errors on some platforms: Android NDK r16.
  • The value of MB_CUR_MAX is too small (3 instead of 4) in UTF-8 locales on some platforms: Solaris 10.

Portability problems fixed by the Gnulib module system-posix:

  • The macros WIFSIGNALED, WIFEXITED, WIFSTOPPED, WTERMSIG, WEXITSTATUS, WNOHANG, WUNTRACED, WSTOPSIG are not defined in this header file (only in <sys/wait.h>) on some platforms: MirBSD 10.
  • The macro WCOREDUMP is not defined in this header file (only in <sys/wait.h>) on some platforms: glibc 2.42.

Portability problems not fixed by Gnulib:

  • The definition of the type once_flag, of the macro ONCE_FLAG_INIT, and the declaration of the function call_once, that are required by ISO C 23, are not provided. To get them, import Gnulib module call_once and include <threads.h> rather than <stdlib.h>.
  • System status macros such as WEXITSTATUS require an lvalue argument on some platforms. macOS 11.1.
  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the headers <fcntl.h>, <limits.h>, <math.h>, <stddef.h>, and <sys/wait.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.58 stdnoreturn.h

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.25.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/stdnoreturn.h.html

Gnulib module: stdnoreturn-h

Portability problems fixed by Gnulib:

  • This header file is missing on many platforms: FreeBSD 6.4, NetBSD 7.1, OpenBSD 7.9, Minix 3.3.0, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 2.9.0, mingw, MSVC 14, Android 9.0.
  • This file conflicts with some system header files, such as <stdlib.h> and <process.h>, on some platforms: MSVC/clang.

Portability problems not fixed by Gnulib:

  • <stdnoreturn.h> and the noreturn macro are obsolescent in C23.
  • <stdnoreturn.h> cannot be #included in C++ mode on some platforms: FreeBSD 13.1.
  • <stdnoreturn.h> should be #included before ‘_Noreturn’ is used.
  • You cannot assume that _Noreturn is a reserved word; it might be a macro.
  • When the macro lint is defined, standard headers define _Noreturn (and therefore noreturn) to be a macro that expands to the empty token sequence on some platforms: Cygwin 2.5.1, FreeBSD 10.3.
  • On Cygwin 1.7.30 and MSVC 14, noreturn expands to the empty token sequence, to avoid problems with standard headers that use noreturn in combination with __attribute__ or __declspec. Although the resulting code operates correctly, the compiler is not informed whether noreturn functions do not return, so it may generate incorrect warnings at compile-time, or code that is slightly less optimized. This problem does not occur with _Noreturn.
  • Circa 2012 bleeding-edge GCC with -Werror=old-style-declaration requires _Noreturn or noreturn before the returned type in a declaration, and therefore rejects valid but unusually-worded declarations such as void _Noreturn foo (void);.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.59 string.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/string.h.html

Gnulib module: string-h

Portability problems fixed by Gnulib:

  • Some platforms provide a NULL macro that cannot be used in arbitrary expressions: NetBSD 5.0

Portability problems not fixed by Gnulib:

  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the header <stddef.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.60 strings.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/strings.h.html

Gnulib module: strings-h

Portability problems fixed by Gnulib:

  • This header file is not self-contained on some platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: MSVC 14.
  • This header file defines symbols, such as ‘index’, often used for variables, making debugging harder.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.61 sys/ipc.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_ipc.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.62 sys/mman.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_mman.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.
  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the header <fcntl.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.63 sys/msg.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_msg.h.html

Gnulib module: sys_msg-h

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.64 sys/resource.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_resource.h.html

Gnulib module: sys_resource-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.
  • On some platforms, this header file requires that <sys/types.h> and <sys/time.h> already be included: FreeBSD 5.0.
  • On some platforms, this header file does not define the RUSAGE_SELF and RUSAGE_CHILDREN constants: OpenVMS.

Portability problems not fixed by Gnulib:

  • On some platforms, this header does not define some or all of the symbolic constants required by POSIX. For example, OpenVMS and Android do not define RLIM_SAVED_CUR or RLIM_SAVED_MAX.
  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the header <sys/time.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.65 sys/select.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_select.h.html

Gnulib module: sys_select-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: HP-UX 11.11, NonStop Kernel, mingw, MSVC 14.
  • This header file is not self-contained on some platforms: it requires <sys/types.h> to be included first.
  • This header file is not self-contained—it requires <string.h> before FD_ZERO can be used—on some platforms: AIX 7.1, Solaris 11.4.

Portability problems not fixed by Gnulib:

  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the headers <signal.h> and <time.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.66 sys/sem.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_sem.h.html

Gnulib module: sys_sem-h

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.67 sys/shm.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_shm.h.html

Gnulib module: sys_shm-h

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.68 sys/socket.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_socket.h.html

Gnulib module: sys_socket-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.
  • This header file is not self-contained on some platforms: it requires <sys/types.h> to be included first.
  • This header file does not define the type struct iovec on some platforms: OpenBSD 4.4.
  • This header file is lacking the SHUT_RD, SHUT_WR, SHUT_RDWR macros on some platforms, despite having the shutdown functions: emx+gcc.
  • The struct sockaddr_storage type does not have a member ss_family on some platforms: AIX 7.1.
  • The CMSG_SPACE and CMSG_LEN macros are not provided on some platforms: OpenVMS.
  • This header file does not define the SO_REUSEPORT macro on some platforms: Minix 3.1.8, Solaris 10, Cygwin, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • This header file does not declare the msg_control and msg_controllen members of struct msghdr on some platforms. This can be detected by the absence of the CMSG_FIRSTHDR macro: gnulib replacement header, old BSD
  • This header file does not define the macro SOCK_NONBLOCK on some platforms: macOS 15, AIX 7.3, Solaris 10, mingw, MSVC 14.
  • This header file does not define the macros SOCK_CLOEXEC and MSG_CMSG_CLOEXEC on some platforms: macOS 15, AIX 7.3, Solaris 10, mingw, MSVC 14.
  • This header file does not define the macro MSG_CMSG_CLOEXEC on some platforms: Solaris 11 OmniOS.
  • Although POSIX.1-2024 standardized SOCK_CLOFORK and MSG_CMSG_CLOFORK, no known platform supports them.
  • This header file does not define the macro SO_DOMAIN on some platforms: macOS 15, NetBSD 10.0, AIX 7.3, Cygwin 3.5, mingw, MSVC 14.
  • This header file does not define the macro SO_PROTOCOL on some platforms: macOS 15, NetBSD 10.0, AIX 7.3, Solaris 11.4, Cygwin 3.5, mingw, MSVC 14.
  • This header file does not define the macro MSG_NOSIGNAL on some platforms: Solaris 10, mingw, MSVC 14.
  • This header file does not define the macro MSG_EOR on some platforms: mingw, MSVC 14.
  • This header file does not define the macros MSG_CTRUNC and MSG_TRUNC on some platforms: mingw.
  • This header file does not define the macro MSG_WAITALL on some platforms: MSVC 14.
  • This header file does not define the type struct cmsghdr and the constant SCM_RIGHTS on some platforms: mingw, MSVC 14.
  • This header file does not define the constant SOCK_CLOFORK on some platforms: glibc 2.42, musl libc, macOS, FreeBSD, NetBSD, OpenBSD, AIX, Solaris 11.3, Cygwin, mingw, MSVC, Android.
  • This header file does not define the constant MSG_CMSG_CLOFORK on some platforms: glibc 2.42, musl libc, macOS, FreeBSD, NetBSD, OpenBSD, AIX, Solaris 11.4, Cygwin, mingw, MSVC, Android.
  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the header <sys/uio.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.69 sys/stat.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_stat.h.html

Gnulib module: sys_stat-h

Portability problems fixed by Gnulib module sys_stat-h:

  • The type mode_t is not defined on some platforms: MSVC 14.
  • The type blksize_t is not defined on some platforms: FreeBSD 5.5, OpenBSD 5.6, HP-UX 11.23, mingw, MSVC 14.
  • The type blkcnt_t is not defined on some platforms: FreeBSD 5.5, OpenBSD 5.6, mingw, MSVC 14.
  • Some macros, such as S_IFMT or S_IFIFO, are missing on some platforms.
  • The macros S_ISBLK, S_ISCHR, S_ISDIR, S_ISFIFO, S_ISLNK, S_ISREG, S_ISSOCK are broken on some platforms.
  • Some platforms define macros, such as S_ISDOOR, that are not defined on other platforms.
  • The functions lstat and mkdir are not declared on some platforms: mingw, MSVC 14.
  • The macros UTIME_NOW and UTIME_OMIT are missing on some platforms.
  • On some platforms, struct stat does not include st_atim, st_mtim, or st_ctim members. Use the gnulib module ‘stat-time’ for accessors to portably get at subsecond resolution.

Portability problems fixed by Gnulib module sys_stat-h, together with module windows-stat-inodes:

  • On Windows platforms (excluding Cygwin), st_ino is always 0.

On platforms where off_t is a 32-bit type, struct stat cannot represent the size of files or block devices 2 GiB or lager and may not work correctly on directories 2 GiB or larger. Also, on platforms where ino_t is a 32-bit type, struct stat cannot represent larger inode numbers. See Large File Support, for how to address these problems.

See Avoiding the year 2038 problem, for portability issues with the time_t components of struct stat.

Portability problems not fixed by Gnulib:

  • On some platforms the types blksize_t and blkcnt_t are unsigned: QNX, Android, glibc/alpha.
  • The macro S_IFBLK is missing on some platforms: MSVC 14.
  • On OpenVMS, st_ino is an array of three ino_t values, not a single value. b are known to represent the same file.
  • On some platforms, two different files may have the same st_dev and st_ino values, even when st_ino is nonzero:
    • GNU/Linux NFS servers that export all local file systems as a single NFS file system, if a local st_dev exceeds 255, or if a local st_ino exceeds 16777215.
    • Network Appliance NFS servers in snapshot directories; see Network Appliance bug #195.
    • ClearCase MVFS; see bug id ATRia04618.
  • On some file systems, st_size contains bogus information for symlinks; use the Gnulib module areadlink-with-size for a better way to get symlink contents.
  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the header <time.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

To partially work around porting problems with Microsoft Windows and OpenVMS, you can use the Gnulib same-inode module to test whether two struct stat objects are known to represent the same file. For example, psame_inode (&a, &b) is true if the struct stat objects a and b are known to represent the same file.

Another partial workaround is to compare other file metadata such as st_mode and st_mtime on platforms where st_dev and st_ino not uniquely identify a file. However, this does not work reliably on files whose metadata are being changed by other programs, or where the metadata happen to be equal.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.70 sys/statvfs.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_statvfs.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: OpenBSD 3.8, mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.71 sys/time.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_time.h.html

Gnulib module: sys_time-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: MSVC 14.
  • ‘struct timeval’ is not defined on some platforms.
  • ‘struct timeval’ is defined with a tv_sec type that is narrower than time_t on some native Windows platforms: mingw64 in 64-bit mode, mingw64 in 32-bit mode when __MINGW_USE_VC2005_COMPAT is defined, MSVC 14 in 64-bit mode, MSVC 14 in 32-bit mode when _USE_32BIT_TIME_T is not defined.

See Avoiding the year 2038 problem, for portability issues with time_t and the time_t component of struct timeval.

Portability problems not fixed by Gnulib:

  • ‘struct timeval’ is defined with a tv_sec type that is wider than time_t: OpenBSD 5.1 in 64-bit mode.
  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the header <sys/select.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.72 sys/times.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_times.h.html

Gnulib module: sys_times-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.73 sys/types.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_types.h.html

Gnulib module: sys_types-h

Portability problems fixed by Gnulib:

  • The type pid_t is not defined on some platforms: MSVC 14.
  • The type size_t is not defined in this file on some platforms: MSVC 14.
  • The type ssize_t is not defined on some platforms: MSVC 14.
  • The type mode_t is not defined on some platforms: MSVC 14.
  • The type off64_t is not defined on some platforms: macOS 14, FreeBSD 10.4, NetBSD 10.0, OpenBSD 7.9, MSVC 14, Cygwin, Haiku, Minix 3.3.
  • The type blksize_t is not defined on some platforms: FreeBSD 5.5, OpenBSD 5.6, HP-UX 11.23, mingw, MSVC 14.
  • The type blkcnt_t is not defined on some platforms: FreeBSD 5.5, OpenBSD 5.6, mingw, MSVC 14.
  • Some systems leak definitions of major, minor, and makedev through this header; however, when sys/sysmacros.h exists, that file should also be included to avoid deprecation warnings from the versions in this header: glibc 2.25.

See Avoiding the year 2038 problem, for portability issues with time_t.

Portability problems not fixed by Gnulib:

  • On some platforms the types blksize_t and blkcnt_t are unsigned: QNX, Android, glibc/alpha.
  • On some platforms the types blksize_t and suseconds_t are signed integer types that are wider than long: glibc x32

This module, together with the module largefile, also defines the type off_t to a 64-bit integer type on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.74 sys/uio.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_uio.h.html

Gnulib module: sys_uio-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.
  • This header file is not self-contained (it requires <sys/types.h> to be included first) on some platforms: OpenBSD 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.75 sys/un.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_un.h.html

Gnulib module: sys_un-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.
  • This header file does not define the sa_family_t type on some platforms: Cygwin 3.5.5, mingw, MSVC 14.
  • This header file causes compilation errors in C++ mode on some platforms: glibc 2.42.

Portability problems not fixed by Gnulib:

  • This header requires sys/socket.h to be included first on some platforms: Cygwin 1.7.18.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.76 sys/utsname.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_utsname.h.html

Gnulib module: sys_utsname-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.
  • This header file is not self-contained on some platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.77 sys/wait.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/sys_wait.h.html

Gnulib module: sys_wait-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.
  • This header file does not define the WCOREDUMP macro on some platforms: AIX 7.3, Haiku.

Portability problems not fixed by Gnulib:

  • System status macros such as WEXITSTATUS require an lvalue argument on some platforms: macOS 11.1.
  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the header <signal.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.78 syslog.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/syslog.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.79 tar.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/tar.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: Cygwin 1.5.x, mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.80 termios.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/termios.h.html

Gnulib module: termios-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.
  • This header does not declare pid_t on all platforms: glibc on some architectures, FreeBSD 6.4, OpenBSD 4.9, Cygwin 1.7.11.

Portability problems not fixed by Gnulib:

  • The types struct termios, struct winsize, cc_t, speed_t, tcflag_t are not defined on some platforms: mingw, MSVC 14.
  • struct winsize is defined in sys/ioctl.h on some platforms: glibc, AIX.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.81 tgmath.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/tgmath.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: Mac OS X 10.5, FreeBSD 5.2.1, NetBSD 10.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.7.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.82 threads.h

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/threads.h.html

Defines the multithreading facility of ISO C11.

Gnulib module: threads-h

Portability problems fixed by Gnulib:

  • This header file is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 2.2.x, mingw, MSVC 14, Android 9.0.
  • This header file defines thrd_start_t incorrectly on some platforms: AIX 7.2.
  • This header file does not define TSS_DTOR_ITERATIONS on some platforms: AIX 7.2.

Portability problems not fixed by Gnulib:

  • There is no way to define a working thread_local macro on some platforms:
    • Mac OS X 10.5,
    • OpenBSD 6.5,
    • AIX 7.1 with gcc (but it works with ‘xlc -qthreaded -qtls’),
    • HP-UX 11.31 with cc (but it works with gcc),
    • Android 4.3.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.83 time.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/time.h.html

Gnulib module: time-h

Portability problems fixed by Gnulib:

  • ‘struct timespec’ is not defined on some platforms.
  • The macro TIME_UTC is not defined on many platforms: glibc 2.15, macOS 10.13, FreeBSD 11.0, NetBSD 7.1, OpenBSD 6.0, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • Some platforms provide a NULL macro that cannot be used in arbitrary expressions: NetBSD 5.0.

Portability problems fixed by the Gnulib module year2038:

  • On some platforms where time_t defaults to 32-bit but can be changed to 64-bit, functions like stat can fail with errno == EOVERFLOW when a 32-bit timestamp is out of range, such as with a file timestamp in the far future or past: glibc 2.34+ atop 32-bit x86 or ARM Linux. See Avoiding the year 2038 problem.

Portability problems not fixed by Gnulib:

  • On some platforms struct tm lacks the the tm_gmtoff and tm_zone members: AIX 7.3, HP-UX 11, Solaris 11.4, mingw, MSVC 14.
  • On some platforms the global state variables daylight, timezone and tzname are not available. Even on platforms where they are available, their contents are often unreliable, even in single-threaded processes. Portable code can instead use struct tm’s tm_gmtoff and tm_zone members when available, and the strftime function with %z or %Z conversion specifiers otherwise.
  • On platforms where time_t is always 32-bit, functions like stat can fail with errno == EOVERFLOW when a timestamp is out of range, such as with a file timestamp in the far future or past; on other such platforms, the functions silently return the low-order 32 bits of the correct timestamp. These platforms will be obsolete when 32-bit time_t rolls around, which will occur in 2038 for the typical case when time_t is signed. See Avoiding the year 2038 problem.
  • On some platforms the tv_nsec member of struct timespec is not of type long, but is of type long long instead: glibc x32
  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the header <signal.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.84 uchar.h

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.30.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/uchar.h.html

Defines the types char16_t, char32_t, mbstate_t and size_t, and declares the functions mbrtoc16, c16rtomb, mbrtoc32, c32rtomb.

Gnulib module: uchar-h or uchar-h-c23

Portability problems fixed by either Gnulib module uchar-h or uchar-h-c23:

  • This header file is missing on many non-glibc platforms: glibc 2.15, macOS 14, FreeBSD 6.4, NetBSD 10.0, OpenBSD 7.3, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.4.x, mingw, MSVC 9.
  • This file is not self-contained on some platforms: Haiku.
  • This file produces compilation errors in C++ mode on some platforms: AIX 7.2 with xlclang++.

Portability problems fixed by Gnulib module uchar-h-c23:

  • char32_t values may not be Unicode code points. This is the case in ISO C 11 compliant but not ISO C 23 compliant implementations.

Portability problems fixed by Gnulib modules btoc32, c32_apply_mapping, c32_apply_type_test, c32_get_mapping, c32_get_type_test, c32isalnum, c32isalpha, c32isblank, c32iscntrl, c32isdigit, c32isgraph, c32islower, c32isprint, c32ispunct, c32isspace, c32isupper, c32isxdigit, c32rtomb, c32snrtombs, c32srtombs, c32stombs, c32swidth, c32tob, c32tolower, c32toupper, c32width:

  • The char32_t type of ISO C 23 and POSIX <uchar.h> lacks counterparts of several standard wchar_t functions declared in <wchar.h> and <wctype.h>. This shortcoming is ameliorated by these Gnulib modules, each of which arranges for <uchar.h> to declare a Gnulib-specific function and to make visible the symbols wint_t and WEOF if the symbols are part of that function’s API.

Portability problems not fixed by Gnulib:

  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the headers <stddef.h>, <stdint.h>, and <wchar.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.85 unistd.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/unistd.h.html

Gnulib module: unistd-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: MSVC 14.
  • The type off64_t is not defined on some platforms: macOS 14, FreeBSD 10.4, NetBSD 10.0, OpenBSD 7.9, MSVC 14, Cygwin, Haiku, Minix 3.3.
  • The SEEK_* macros are not defined in this file on some platforms: mingw.
  • The *_FILENO macros are not defined in this file on some platforms: OS/2 EMX, mingw.
  • The _exit function is not declared in this file on some platforms: mingw.
  • This header file does not define O_CLOEXEC on some platforms: glibc 2.42, macOS 12, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5, mingw.
  • Some platforms provide a NULL macro that cannot be used in arbitrary expressions: NetBSD 5.0

Portability problems not fixed by Gnulib:

  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the headers <fcntl.h>, <stddef.h>, <stdint.h>, and <stdio.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.86 utmpx.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/utmpx.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: FreeBSD 8.4, OpenBSD 7.2, Minix 3.1.8, mingw, MSVC 14, Android 13.0.
  • While some platforms have the struct utmpx field ut_user, older platforms have the field ut_name.
  • The struct utmpx field ut_exit does not exist on some platforms: macOS, FreeBSD, AIX, Cygwin.
  • The struct utmpx field ut_session does not exist on some platforms: macOS, FreeBSD, AIX, HP-UX, Cygwin.
  • The struct utmpx field ut_addr or ut_addr_v6 or ut_ss does not exist on some platforms: macOS, FreeBSD, AIX, Solaris.
  • On some platforms, the struct utmpx field ut_tv is not of type struct timeval. Instead, it is a different struct with tv_sec and tv_usec members that may have different types than the members of struct timeval: glibc 2.42 on platforms where time_t was historically 32 bits and where log file formats were not changed when 64-bit time_t was introduced.
  • On some platforms, this API does not support timestamps past the year 2038: glibc 2.39 on 32-bit platforms like x86 and ARM where time_t was historically 32 bits; later glibc versions support timestamps up to the year 2106, by changing ut_tv.tv_sec’s type to be a 32-bit unsigned integer.
  • On some platforms, this header misbehaves if the year2038 or year2038-recommended modules are used and the program is configured without the --disable-year2038 option. The readutmp module works around this problem: glibc 2.38 on 32-bit platforms like x86 and ARM where time_t was historically 32 bits. See Avoiding the year 2038 problem.
  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the header <sys/time.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.87 wchar.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/wchar.h.html

Gnulib module: wchar-h

Portability problems fixed by Gnulib:

  • This header file cannot be included on some platforms: Linux uClibc built without wide character support.
  • The type wint_t is incorrect on some platforms: mingw, MSVC 14.
  • Some platforms provide a NULL macro that cannot be used in arbitrary expressions: NetBSD 5.0

Portability problems not fixed by Gnulib:

  • In multibyte locales, wchar_t values need not be Unicode code points: FreeBSD 15, NetBSD 10, AIX, Solaris.
  • In single-byte locales, wchar_t values need not be Unicode code points: FreeBSD 15, NetBSD 10, OpenBSD 7, macOS 26, Solaris, mingw, MSVC.
  • wchar_t is only 16 bits, and so can represent only a UTF-16 subset of Unicode when wchar_t values are Unicode code points: 32-bit AIX, mingw, MSVC.
  • This header file leads to link errors and endless recursions or endless loops on some platforms: glibc version 2.5 or older, together with gcc version 4.3 or newer and the option ‘-std=c99’ or ‘-std=gnu99’.
  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the headers <ctype.h>, <stdarg.h>, <stddef.h>, <stdlib.h>, <stdio.h>, <string.h>, and <time.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Next: , Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.88 wctype.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/wctype.h.html

Gnulib module: wctype-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: HP-UX 11.00.
  • The type wint_t is incorrect on some platforms: mingw, MSVC 14.
  • The functions isw* are missing on some platforms: FreeBSD 4.11.

Portability problems not fixed by Gnulib:

  • POSIX.1-2024 allows, but does not require, this file to make visible all symbols from the headers <ctype.h>, <stdarg.h>, <stddef.h>, <stdlib.h>, <stdio.h>, <string.h>, <time.h>, and <wchar.h>. Programs should not assume that these other symbols are visible merely because this file is included, or that they are invisible because only this file is included.

Previous: , Up: ISO C and POSIX Header File Substitutes   [Contents][Index]

9.89 wordexp.h

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/wordexp.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

10 ISO C and POSIX Function Substitutes

This chapter describes which functions and function-like macros specified by ISO C (including ISO TS 18661-1) or POSIX are substituted by Gnulib, which portability pitfalls are fixed by Gnulib, and which (known) portability problems are not worked around by Gnulib.

The notation “Gnulib module: —” means that Gnulib does not provide a module providing a substitute for the function. When the list “Portability problems not fixed by Gnulib” is empty, such a module is not needed: No portability problems are known. Otherwise, it indicates that such a module would be useful but is not available: No one so far found this function important enough to contribute a substitute for it. If you need this particular function, you may write to <bug-gnulib at gnu dot org>.

This list of functions is sorted according to the header that declares them.

Next: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.1 Functions in <aio.h>

Next: , Up: Functions in <aio.h>   [Contents][Index]

10.1.1 aio_cancel

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/aio_cancel.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, this function may not work correctly on files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.10.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <aio.h>   [Contents][Index]

10.1.2 aio_error

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/aio_error.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, this function may not work correctly on files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Cygwin 2.10.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <aio.h>   [Contents][Index]

10.1.3 aio_fsync

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/aio_fsync.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, this function may not work correctly on files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Cygwin 2.10.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <aio.h>   [Contents][Index]

10.1.4 aio_read

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/aio_read.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, this function may not work correctly on files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.10.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <aio.h>   [Contents][Index]

10.1.5 aio_return

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/aio_return.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, this function may not work correctly on files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Cygwin 2.10.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <aio.h>   [Contents][Index]

10.1.6 aio_suspend

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/aio_suspend.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, this function may not work correctly on files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.10.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <aio.h>   [Contents][Index]

10.1.7 aio_write

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/aio_write.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, this function may not work correctly on files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.10.x, mingw, MSVC 14, Android 9.0.

Previous: , Up: Functions in <aio.h>   [Contents][Index]

10.1.8 lio_listio

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lio_listio.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, this function may not work correctly on files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.10.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.2 Functions in <arpa/inet.h>

Next: , Up: Functions in <arpa/inet.h>   [Contents][Index]

10.2.1 htonl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/htonl.html

Gnulib module: htonl

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11, Android API level 20.
  • This function is declared in <winsock2.h> instead of <arpa/inet.h> on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <arpa/inet.h>   [Contents][Index]

10.2.2 htons

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/htons.html

Gnulib module: htonl

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11, Android API level 20.
  • This function is declared in <winsock2.h> instead of <arpa/inet.h> on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <arpa/inet.h>   [Contents][Index]

10.2.3 inet_addr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/inet_addr.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <arpa/inet.h> on some platforms: mingw, MSVC 14.
  • POSIX.1-2024 says this function is obsolescent and it is planned to be removed in a future version. Use the function inet_pton instead.
  • On some old platforms, this function returns a ‘struct in_addr’ rather than a scalar type such as ‘unsigned int’ or ‘unsigned long’.

Next: , Previous: , Up: Functions in <arpa/inet.h>   [Contents][Index]

10.2.4 inet_ntoa

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/inet_ntoa.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <arpa/inet.h> on some platforms: mingw, MSVC 14.
  • POSIX.1-2024 says this function is obsolescent and it is planned to be removed in a future version. Use the function inet_ntop instead.
  • The inet_ntoa function need not be reentrant, and consequently is not required to be thread safe. Implementations of inet_ntoa typically write the timestamp into static buffer. If two threads call inet_ntoa at roughly the same time, you might end up with the wrong date in one of the threads, or some undefined string.

Note: inet_ntoa is specific for IPv4 addresses. A protocol independent function is inet_ntop.

Next: , Previous: , Up: Functions in <arpa/inet.h>   [Contents][Index]

10.2.5 inet_ntop

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/inet_ntop.html

Gnulib module: inet_ntop

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11.00, mingw, MSVC 14.
  • This function is declared in <netdb.h> instead of <arpa/inet.h> on some platforms: NonStop Kernel.
  • This function is declared in <ws2tcpip.h>, with a POSIX incompatible declaration, on some platforms: MSVC 14 on Windows >= Vista.

Portability problems not fixed by Gnulib:

  • This function’s fourth argument type is size_t instead of socklen_t on some platforms: Solaris 10.

Next: , Previous: , Up: Functions in <arpa/inet.h>   [Contents][Index]

10.2.6 inet_pton

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/inet_pton.html

Gnulib module: inet_pton

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11.00, mingw, MSVC 14.
  • This function is declared in <netdb.h> instead of <arpa/inet.h> on some platforms: NonStop Kernel.
  • This function is declared in <ws2tcpip.h>, with a POSIX incompatible declaration, on some platforms: MSVC 14 on Windows >= Vista.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <arpa/inet.h>   [Contents][Index]

10.2.7 ntohl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ntohl.html

Gnulib module: htonl

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11, Android API level 20.
  • This function is declared in <winsock2.h> instead of <arpa/inet.h> on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Previous: , Up: Functions in <arpa/inet.h>   [Contents][Index]

10.2.8 ntohs

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ntohs.html

Gnulib module: htonl

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11, Android API level 20.
  • This function is declared in <winsock2.h> instead of <arpa/inet.h> on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.3 Functions in <assert.h>

Up: Functions in <assert.h>   [Contents][Index]

10.3.1 assert

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/assert.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Extension: Gnulib offers a module ‘assert’ that allows the installer to disable assertions through a ‘configure’ option: ‘--disable-assert’.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.4 Functions in <complex.h>

Next: , Up: Functions in <complex.h>   [Contents][Index]

10.4.1 CMPLX

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.3.9.3.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/CMPLX.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This macro is missing on many platforms: glibc with GCC 4.9.x or clang 18, Mac OS X 10.5, FreeBSD 6.4, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.1, HP-UX 11.11, Solaris 11.0, Solaris 11 OpenIndiana, Cygwin, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.2 CMPLXF

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.3.9.3.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/CMPLXF.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This macro is missing on many platforms: glibc with GCC 4.9.x or clang 18, Mac OS X 10.5, FreeBSD 6.4, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.1, HP-UX 11.11, Solaris 11.0, Solaris 11 OpenIndiana, Cygwin, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.3 CMPLXL

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.3.9.3.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/CMPLXL.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This macro is missing on many platforms: glibc with GCC 4.9.x or clang 18, Mac OS X 10.5, FreeBSD 6.4, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.1, HP-UX 11.11, Solaris 11.0, Solaris 11 OpenIndiana, Cygwin, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.4 cabs

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cabs.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11, Solaris 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.5 cabsf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cabsf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.6 cabsl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cabsl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 10.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 5.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.7 cacos

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cacos.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9, Android 5.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.8 cacosf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cacosf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9, Android 5.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.9 cacosh

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cacosh.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9, Android 5.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.10 cacoshf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cacoshf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9, Android 5.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.11 cacoshl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cacoshl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 11.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 7.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.12 cacosl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cacosl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 11.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 7.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.13 carg

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/carg.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.14 cargf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cargf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.15 cargl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cargl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 5.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.16 casin

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/casin.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9, Android 5.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.17 casinf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/casinf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9, Android 5.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.18 casinh

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/casinh.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9, Android 5.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.19 casinhf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/casinhf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9, Android 5.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.20 casinhl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/casinhl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 11.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 7.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.21 casinl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/casinl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 11.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 7.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.22 catan

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/catan.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9, Android 5.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.23 catanf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/catanf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9, Android 5.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.24 catanh

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/catanh.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9, Android 5.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.25 catanhf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/catanhf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9, Android 5.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.26 catanhl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/catanhl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 11.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 7.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.27 catanl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/catanl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 11.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 7.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.28 ccos

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ccos.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.29 ccosf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ccosf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.30 ccosh

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ccosh.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.31 ccoshf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ccoshf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.32 ccoshl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ccoshl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 14.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 7.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.33 ccosl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ccosl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 14.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 7.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.34 cexp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cexp.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.35 cexpf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cexpf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.36 cexpl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cexpl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 13.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 7.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.37 cimag

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cimag.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.38 cimagf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cimagf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.39 cimagl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cimagl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 5.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.40 clog

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/clog.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 11.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9, Android 7.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.41 clogf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/clogf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 11.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9, Android 7.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.42 clogl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/clogl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 11.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 7.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.43 conj

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/conj.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.44 conjf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/conjf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.45 conjl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/conjl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 5.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.46 cpow

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cpow.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 11.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9, Android 7.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.47 cpowf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cpowf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 11.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9, Android 7.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.48 cpowl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cpowl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 11.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 7.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.49 cproj

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cproj.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.
  • The glibc implementation is or was broken.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.50 cprojf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cprojf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.
  • The glibc implementation is or was broken.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.51 cprojl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cprojl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 5.1.
  • The glibc implementation is or was broken.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.52 creal

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/creal.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.53 crealf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/crealf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.54 creall

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/creall.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 5.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.55 csin

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/csin.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.56 csinf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/csinf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.57 csinh

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/csinh.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.58 csinhf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/csinhf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.59 csinhl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/csinhl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 14.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 7.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.60 csinl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/csinl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 14.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 7.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.61 csqrt

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/csqrt.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.62 csqrtf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/csqrtf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.63 csqrtl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/csqrtl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 5.1.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.64 ctan

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ctan.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.65 ctanf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ctanf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.66 ctanh

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ctanh.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.67 ctanhf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ctanhf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.68 ctanhl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ctanhl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 14.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 7.1.

Previous: , Up: Functions in <complex.h>   [Contents][Index]

10.4.69 ctanl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ctanl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 14.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 7.1.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.5 Functions in <ctype.h>

Next: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.1 isalnum

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isalnum.html

Gnulib module: ctype

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Note: This function’s behaviour depends on the locale, but does not support the multibyte characters that occur in strings in locales with MB_CUR_MAX > 1 (this includes all the common UTF-8 locales). There are five alternative APIs:

c_isalnum

This function operates in a locale independent way and returns true only for ASCII characters. It is provided by the Gnulib module ‘c-ctype’.

iswalnum

This function operates in a locale dependent way, on wide characters. In order to use it, you first have to convert from multibyte to wide characters, using the mbrtowc function. It is provided by the Gnulib module ‘wctype’.

c32isalnum

This function operates in a locale dependent way, on 32-bit wide characters. In order to use it, you first have to convert from multibyte to 32-bit wide characters, using the mbrtoc32 function. It is provided by the Gnulib module ‘c32isalnum’.

mb_isalnum

This function operates in a locale dependent way, on multibyte characters. It is provided by the Gnulib module ‘mbchar’.

uc_is_alnum

This function operates in a locale independent way, on Unicode characters. It is provided by the Gnulib module ‘unictype/ctype-alnum’.

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.2 isalnum_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isalnum_l.html

Gnulib module: isalnum_l

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 6.1, OpenBSD 6.1, Minix 3.1.8, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.3 isalpha

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isalpha.html

Gnulib module: ctype

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Note: This function’s behaviour depends on the locale, but does not support the multibyte characters that occur in strings in locales with MB_CUR_MAX > 1 (this includes all the common UTF-8 locales). There are five alternative APIs:

c_isalpha

This function operates in a locale independent way and returns true only for ASCII characters. It is provided by the Gnulib module ‘c-ctype’.

iswalpha

This function operates in a locale dependent way, on wide characters. In order to use it, you first have to convert from multibyte to wide characters, using the mbrtowc function. It is provided by the Gnulib module ‘wctype’.

c32isalpha

This function operates in a locale dependent way, on 32-bit wide characters. In order to use it, you first have to convert from multibyte to 32-bit wide characters, using the mbrtoc32 function. It is provided by the Gnulib module ‘c32isalpha’.

mb_isalpha

This function operates in a locale dependent way, on multibyte characters. It is provided by the Gnulib module ‘mbchar’.

uc_is_alpha

This function operates in a locale independent way, on Unicode characters. It is provided by the Gnulib module ‘unictype/ctype-alpha’.

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.4 isalpha_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isalpha_l.html

Gnulib module: isalpha_l

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 6.1, OpenBSD 6.1, Minix 3.1.8, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.5 isblank

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isblank.html

Gnulib module: isblank

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Solaris 9, mingw, MSVC 9.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Note: This function’s behaviour depends on the locale, but does not support the multibyte characters that occur in strings in locales with MB_CUR_MAX > 1 (this includes all the common UTF-8 locales). There are five alternative APIs:

c_isblank

This function operates in a locale independent way and returns true only for ASCII characters. It is provided by the Gnulib module ‘c-ctype’.

iswblank

This function operates in a locale dependent way, on wide characters. In order to use it, you first have to convert from multibyte to wide characters, using the mbrtowc function. It is provided by the Gnulib module ‘wctype’.

c32isblank

This function operates in a locale dependent way, on 32-bit wide characters. In order to use it, you first have to convert from multibyte to 32-bit wide characters, using the mbrtoc32 function. It is provided by the Gnulib module ‘c32isblank’.

mb_isblank

This function operates in a locale dependent way, on multibyte characters. It is provided by the Gnulib module ‘mbchar’.

uc_is_blank

This function operates in a locale independent way, on Unicode characters. It is provided by the Gnulib module ‘unictype/ctype-blank’.

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.6 isblank_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isblank_l.html

Gnulib module: isblank_l

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 6.1, OpenBSD 6.1, Minix 3.1.8, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.7 iscntrl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iscntrl.html

Gnulib module: ctype

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Note: This function’s behaviour depends on the locale, but does not support the multibyte characters that occur in strings in locales with MB_CUR_MAX > 1 (this includes all the common UTF-8 locales). There are five alternative APIs:

c_iscntrl

This function operates in a locale independent way and returns true only for ASCII characters. It is provided by the Gnulib module ‘c-ctype’.

iswcntrl

This function operates in a locale dependent way, on wide characters. In order to use it, you first have to convert from multibyte to wide characters, using the mbrtowc function. It is provided by the Gnulib module ‘wctype’.

c32iscntrl

This function operates in a locale dependent way, on 32-bit wide characters. In order to use it, you first have to convert from multibyte to 32-bit wide characters, using the mbrtoc32 function. It is provided by the Gnulib module ‘c32iscntrl’.

mb_iscntrl

This function operates in a locale dependent way, on multibyte characters. It is provided by the Gnulib module ‘mbchar’.

uc_is_cntrl

This function operates in a locale independent way, on Unicode characters. It is provided by the Gnulib module ‘unictype/ctype-cntrl’.

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.8 iscntrl_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iscntrl_l.html

Gnulib module: iscntrl_l

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 6.1, OpenBSD 6.1, Minix 3.1.8, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.9 isdigit

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isdigit.html

Gnulib module: ctype

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

  • This function’s behavior depends on locale, and it can return nonzero on arguments other than the usual decimal digits: mingw, MSVC.

Note: This function does not support the multibyte characters that occur in strings in locales with MB_CUR_MAX > 1 (this includes all the common UTF-8 locales). There are five alternative APIs:

c_isdigit

This function operates in a locale independent way and returns true only for ASCII characters. It is provided by the Gnulib module ‘c-ctype’.

iswdigit

This function operates in a locale dependent way, on wide characters. In order to use it, you first have to convert from multibyte to wide characters, using the mbrtowc function. It is provided by the Gnulib module ‘wctype’.

c32isdigit

This function operates in a locale dependent way, on 32-bit wide characters. In order to use it, you first have to convert from multibyte to 32-bit wide characters, using the mbrtoc32 function. It is provided by the Gnulib module ‘c32isdigit’.

mb_isdigit

This function operates in a locale dependent way, on multibyte characters. It is provided by the Gnulib module ‘mbchar’.

uc_is_digit

This function operates in a locale independent way, on Unicode characters. It is provided by the Gnulib module ‘unictype/ctype-digit’.

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.10 isdigit_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isdigit_l.html

Gnulib module: isdigit_l

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 6.1, OpenBSD 6.1, Minix 3.1.8, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.11 isgraph

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isgraph.html

Gnulib module: ctype

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Note: This function’s behaviour depends on the locale, but does not support the multibyte characters that occur in strings in locales with MB_CUR_MAX > 1 (this includes all the common UTF-8 locales). There are five alternative APIs:

c_isgraph

This function operates in a locale independent way and returns true only for ASCII characters. It is provided by the Gnulib module ‘c-ctype’.

iswgraph

This function operates in a locale dependent way, on wide characters. In order to use it, you first have to convert from multibyte to wide characters, using the mbrtowc function. It is provided by the Gnulib module ‘wctype’.

c32isgraph

This function operates in a locale dependent way, on 32-bit wide characters. In order to use it, you first have to convert from multibyte to 32-bit wide characters, using the mbrtoc32 function. It is provided by the Gnulib module ‘c32isgraph’.

mb_isgraph

This function operates in a locale dependent way, on multibyte characters. It is provided by the Gnulib module ‘mbchar’.

uc_is_graph

This function operates in a locale independent way, on Unicode characters. It is provided by the Gnulib module ‘unictype/ctype-graph’.

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.12 isgraph_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isgraph_l.html

Gnulib module: isgraph_l

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 6.1, OpenBSD 6.1, Minix 3.1.8, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.13 islower

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/islower.html

Gnulib module: ctype

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Note: This function’s behaviour depends on the locale, but does not support the multibyte characters that occur in strings in locales with MB_CUR_MAX > 1 (this includes all the common UTF-8 locales). There are five alternative APIs:

c_islower

This function operates in a locale independent way and returns true only for ASCII characters. It is provided by the Gnulib module ‘c-ctype’.

iswlower

This function operates in a locale dependent way, on wide characters. In order to use it, you first have to convert from multibyte to wide characters, using the mbrtowc function. It is provided by the Gnulib module ‘wctype’.

c32islower

This function operates in a locale dependent way, on 32-bit wide characters. In order to use it, you first have to convert from multibyte to 32-bit wide characters, using the mbrtoc32 function. It is provided by the Gnulib module ‘c32islower’.

mb_islower

This function operates in a locale dependent way, on multibyte characters. It is provided by the Gnulib module ‘mbchar’.

uc_is_lower

This function operates in a locale independent way, on Unicode characters. It is provided by the Gnulib module ‘unictype/ctype-lower’.

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.14 islower_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/islower_l.html

Gnulib module: islower_l

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 6.1, OpenBSD 6.1, Minix 3.1.8, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.15 isprint

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isprint.html

Gnulib module: ctype

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Note: This function’s behaviour depends on the locale, but does not support the multibyte characters that occur in strings in locales with MB_CUR_MAX > 1 (this includes all the common UTF-8 locales). There are five alternative APIs:

c_isprint

This function operates in a locale independent way and returns true only for ASCII characters. It is provided by the Gnulib module ‘c-ctype’.

iswprint

This function operates in a locale dependent way, on wide characters. In order to use it, you first have to convert from multibyte to wide characters, using the mbrtowc function. It is provided by the Gnulib module ‘wctype’.

c32isprint

This function operates in a locale dependent way, on 32-bit wide characters. In order to use it, you first have to convert from multibyte to 32-bit wide characters, using the mbrtoc32 function. It is provided by the Gnulib module ‘c32isprint’.

mb_isprint

This function operates in a locale dependent way, on multibyte characters. It is provided by the Gnulib module ‘mbchar’.

uc_is_print

This function operates in a locale independent way, on Unicode characters. It is provided by the Gnulib module ‘unictype/ctype-print’.

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.16 isprint_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isprint_l.html

Gnulib module: isprint_l

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 6.1, OpenBSD 6.1, Minix 3.1.8, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.17 ispunct

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ispunct.html

Gnulib module: ctype

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Note: This function’s behaviour depends on the locale, but does not support the multibyte characters that occur in strings in locales with MB_CUR_MAX > 1 (this includes all the common UTF-8 locales). There are five alternative APIs:

c_ispunct

This function operates in a locale independent way and returns true only for ASCII characters. It is provided by the Gnulib module ‘c-ctype’.

iswpunct

This function operates in a locale dependent way, on wide characters. In order to use it, you first have to convert from multibyte to wide characters, using the mbrtowc function. It is provided by the Gnulib module ‘wctype’.

c32ispunct

This function operates in a locale dependent way, on 32-bit wide characters. In order to use it, you first have to convert from multibyte to 32-bit wide characters, using the mbrtoc32 function. It is provided by the Gnulib module ‘c32ispunct’.

mb_ispunct

This function operates in a locale dependent way, on multibyte characters. It is provided by the Gnulib module ‘mbchar’.

uc_is_punct

This function operates in a locale independent way, on Unicode characters. It is provided by the Gnulib module ‘unictype/ctype-punct’.

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.18 ispunct_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ispunct_l.html

Gnulib module: ispunct_l

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 6.1, OpenBSD 6.1, Minix 3.1.8, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.19 isspace

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isspace.html

Gnulib module: ctype

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Note: This function’s behaviour depends on the locale, but does not support the multibyte characters that occur in strings in locales with MB_CUR_MAX > 1 (this includes all the common UTF-8 locales). There are five alternative APIs:

c_isspace

This function operates in a locale independent way and returns true only for ASCII characters. It is provided by the Gnulib module ‘c-ctype’.

iswspace

This function operates in a locale dependent way, on wide characters. In order to use it, you first have to convert from multibyte to wide characters, using the mbrtowc function. It is provided by the Gnulib module ‘wctype’.

c32isspace

This function operates in a locale dependent way, on 32-bit wide characters. In order to use it, you first have to convert from multibyte to 32-bit wide characters, using the mbrtoc32 function. It is provided by the Gnulib module ‘c32isspace’.

mb_isspace

This function operates in a locale dependent way, on multibyte characters. It is provided by the Gnulib module ‘mbchar’.

uc_is_space

This function operates in a locale independent way, on Unicode characters. It is provided by the Gnulib module ‘unictype/ctype-space’.

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.20 isspace_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isspace_l.html

Gnulib module: isspace_l

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 6.1, OpenBSD 6.1, Minix 3.1.8, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.21 isupper

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isupper.html

Gnulib module: ctype

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Note: This function’s behaviour depends on the locale, but does not support the multibyte characters that occur in strings in locales with MB_CUR_MAX > 1 (this includes all the common UTF-8 locales). There are five alternative APIs:

c_isupper

This function operates in a locale independent way and returns true only for ASCII characters. It is provided by the Gnulib module ‘c-ctype’.

iswupper

This function operates in a locale dependent way, on wide characters. In order to use it, you first have to convert from multibyte to wide characters, using the mbrtowc function. It is provided by the Gnulib module ‘wctype’.

c32isupper

This function operates in a locale dependent way, on 32-bit wide characters. In order to use it, you first have to convert from multibyte to 32-bit wide characters, using the mbrtoc32 function. It is provided by the Gnulib module ‘c32isupper’.

mb_isupper

This function operates in a locale dependent way, on multibyte characters. It is provided by the Gnulib module ‘mbchar’.

uc_is_upper

This function operates in a locale independent way, on Unicode characters. It is provided by the Gnulib module ‘unictype/ctype-upper’.

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.22 isupper_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isupper_l.html

Gnulib module: isupper_l

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 6.1, OpenBSD 6.1, Minix 3.1.8, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.23 isxdigit

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isxdigit.html

Gnulib module: ctype

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

  • This function’s behavior depends on locale, and it can return nonzero on arguments other than the usual hexadecimal digits: mingw, MSVC.

Note: This function does not support the multibyte characters that occur in strings in locales with MB_CUR_MAX > 1 (this includes all the common UTF-8 locales). There are five alternative APIs:

c_isxdigit

This function operates in a locale independent way and returns true only for ASCII characters. It is provided by the Gnulib module ‘c-ctype’.

iswxdigit

This function operates in a locale dependent way, on wide characters. In order to use it, you first have to convert from multibyte to wide characters, using the mbrtowc function. It is provided by the Gnulib module ‘wctype’.

c32isxdigit

This function operates in a locale dependent way, on 32-bit wide characters. In order to use it, you first have to convert from multibyte to 32-bit wide characters, using the mbrtoc32 function. It is provided by the Gnulib module ‘c32isxdigit’.

mb_isxdigit

This function operates in a locale dependent way, on multibyte characters. It is provided by the Gnulib module ‘mbchar’.

uc_is_xdigit

This function operates in a locale independent way, on Unicode characters. It is provided by the Gnulib module ‘unictype/ctype-xdigit’.

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.24 isxdigit_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isxdigit_l.html

Gnulib module: isxdigit_l

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 6.1, OpenBSD 6.1, Minix 3.1.8, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.25 tolower

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tolower.html

Gnulib module: ctype

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Note: This function’s behaviour depends on the locale, but does not support the multibyte characters that occur in strings in locales with MB_CUR_MAX > 1 (this includes all the common UTF-8 locales). There are four alternative APIs:

c_tolower

This function operates in a locale independent way and returns a different value than the argument only for uppercase ASCII characters. It is provided by the Gnulib module ‘c-ctype’.

towlower

This function operates in a locale dependent way, on wide characters. In order to use it, you first have to convert from multibyte to wide characters, using the mbrtowc function. It is provided by the Gnulib module ‘wctype’.

c32tolower

This function operates in a locale dependent way, on 32-bit wide characters. In order to use it, you first have to convert from multibyte to 32-bit wide characters, using the mbrtoc32 function. It is provided by the Gnulib module ‘c32tolower’.

uc_tolower

This function operates in a locale independent way, on Unicode characters. It is provided by the Gnulib module ‘unicase/tolower’.

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.26 tolower_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tolower_l.html

Gnulib module: tolower_l

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 6.1, OpenBSD 6.1, Minix 3.1.8, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.27 toupper

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/toupper.html

Gnulib module: ctype

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Note: This function’s behaviour depends on the locale, but does not support the multibyte characters that occur in strings in locales with MB_CUR_MAX > 1 (this includes all the common UTF-8 locales). There are four alternative APIs:

c_toupper

This function operates in a locale independent way and returns a different value than the argument only for lowercase ASCII characters. It is provided by the Gnulib module ‘c-ctype’.

towupper

This function operates in a locale dependent way, on wide characters. In order to use it, you first have to convert from multibyte to wide characters, using the mbrtowc function. It is provided by the Gnulib module ‘wctype’.

c32toupper

This function operates in a locale dependent way, on 32-bit wide characters. In order to use it, you first have to convert from multibyte to 32-bit wide characters, using the mbrtoc32 function. It is provided by the Gnulib module ‘c32toupper’.

uc_toupper

This function operates in a locale independent way, on Unicode characters. It is provided by the Gnulib module ‘unicase/toupper’.

Previous: , Up: Functions in <ctype.h>   [Contents][Index]

10.5.28 toupper_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/toupper_l.html

Gnulib module: toupper_l

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 6.1, OpenBSD 6.1, Minix 3.1.8, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.6 Functions in <devctl.h>

Up: Functions in <devctl.h>   [Contents][Index]

10.6.1 posix_devctl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_devctl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.42, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.7 Functions in <dirent.h>

Next: , Up: Functions in <dirent.h>   [Contents][Index]

10.7.1 alphasort

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/alphasort.html

Gnulib module: alphasort

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Solaris 9, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • The parameters of this function are declared as const void * on some platforms: glibc 2.3.6, macOS 10.7, FreeBSD 6.0, NetBSD 7.1, OpenBSD 7.9.
  • The parameters of this function are declared as void * on some platforms: AIX 5.1.

Next: , Previous: , Up: Functions in <dirent.h>   [Contents][Index]

10.7.2 closedir

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/closedir.html

Gnulib module: closedir

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <dirent.h>   [Contents][Index]

10.7.3 dirfd

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dirfd.html

Gnulib module: dirfd

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 7.1, HP-UX 11, Solaris 10, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • This function always fails on some platforms: mingw.
  • There is a dirfd macro but no function, and the macro does not work with an argument of type void *, as a function would: NetBSD 9.2.

Next: , Previous: , Up: Functions in <dirent.h>   [Contents][Index]

10.7.4 fdopendir

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fdopendir.html

Gnulib module: fdopendir

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.5.x, mingw, MSVC 14. But the replacement function is not safe to be used in libraries and is not thread-safe. Also, the replacement does not guarantee that ‘dirfd(fdopendir(n))==n’ (dirfd might fail, or return a different file descriptor than n).
  • This function exists but is not declared on some platforms: FreeBSD 7.3.
  • This function does not reject non-directory file descriptors on some platforms: GNU/Hurd.
  • This function mistakenly closes non-directory file descriptors on some platforms: FreeBSD 8.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <dirent.h>   [Contents][Index]

10.7.5 opendir

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/opendir.html

Gnulib module: opendir

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: MSVC 14.
  • On platforms where off_t is a 32-bit type, this function may not work correctly on huge directories 2 GiB and larger. Also, on platforms where ino_t is a 32-bit type, this function may report inode numbers incorrectly. See Large File Support.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <dirent.h>   [Contents][Index]

10.7.6 posix_getdents

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_getdents.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.42, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <dirent.h>   [Contents][Index]

10.7.7 readdir

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/readdir.html

Gnulib module: readdir

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: MSVC 14.
  • On platforms where off_t is a 32-bit type, this function may not work correctly on huge directories 2 GiB and larger. Also, on platforms where ino_t is a 32-bit type, this function may report inode numbers incorrectly. This can occur with file systems such as XFS (typically on large disks) and NFS. See Large File Support.

Portability problems not fixed by Gnulib:

  • Although POSIX places no restrictions on d_ino values, some older systems are rumored to return d_ino values equal to zero for directory entries that do not really exist. Although Gnulib formerly attempted to cater to these older systems, this caused misbehavior on standard systems and so Gnulib does not attempt to cater to them any more. If you know of any problems caused by this, please send a bug report.
  • When reading a directory that has been removed, this function sets errno to ENOENT instead of leaving errno alone to indicate EOF: glibc 2.2.5.

Next: , Previous: , Up: Functions in <dirent.h>   [Contents][Index]

10.7.8 readdir_r

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/readdir_r.html

Gnulib module: extensions

Portability problems fixed by Gnulib:

  • This function is planned to be removed from POSIX and to be deprecated in glibc. Portable applications should use readdir.
  • This function has an incompatible declaration on some platforms: Solaris 11.4 (when _POSIX_PTHREAD_SEMANTICS is not defined).
  • On platforms where off_t is a 32-bit type, this function may not work correctly on huge directories 2 GiB and larger. Also, on platforms where ino_t is a 32-bit type, this function may report inode numbers incorrectly. This can occur with file systems such as XFS (typically on large disks) and NFS. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • When reading a directory that has been removed, this function sets errno to ENOENT instead of leaving errno alone to indicate EOF: glibc 2.2.5.

Next: , Previous: , Up: Functions in <dirent.h>   [Contents][Index]

10.7.9 rewinddir

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/rewinddir.html

Gnulib module: rewinddir

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: MSVC 14.
  • On Mac OS X platforms where long int is a 32-bit type, this function may not work correctly on huge directories 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <dirent.h>   [Contents][Index]

10.7.10 scandir

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/scandir.html

Gnulib module: scandir

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Solaris 9, mingw, MSVC 14.
  • On platforms where off_t is a 32-bit type, this function may not work correctly on huge directories 2 GiB and larger. Also, on platforms where ino_t is a 32-bit type, this function may report inode numbers incorrectly. See Large File Support.

Portability problems not fixed by Gnulib:

  • The fourth parameter of this function is declared as int (*) (const void *, const void *) on some platforms: glibc 2.3.6, macOS 10.7, FreeBSD 6.0, NetBSD 7.1, OpenBSD 7.9.
  • The fourth parameter of this function is declared as int (*) (void *, void *) on some platforms: AIX 5.1.

Next: , Previous: , Up: Functions in <dirent.h>   [Contents][Index]

10.7.11 seekdir

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/seekdir.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where long int is a 32-bit type, this function may not work correctly on huge directories 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: MSVC 14, Android 5.1.

Previous: , Up: Functions in <dirent.h>   [Contents][Index]

10.7.12 telldir

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/telldir.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where long int is a 32-bit type, this function may not work correctly on huge directories 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: MSVC 14, Android 5.1.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.8 Functions in <dlfcn.h>

Next: , Up: Functions in <dlfcn.h>   [Contents][Index]

10.8.1 dladdr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dladdr.html

Documentation:
man dladdr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Cygwin 1.7.x, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <dlfcn.h>   [Contents][Index]

10.8.2 dlclose

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dlclose.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <dlfcn.h>   [Contents][Index]

10.8.3 dlerror

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dlerror.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <dlfcn.h>   [Contents][Index]

10.8.4 dlopen

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dlopen.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-dlopen-1.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • If the file name argument is not absolute, the file is searched for. The search algorithm is system specific.

Previous: , Up: Functions in <dlfcn.h>   [Contents][Index]

10.8.5 dlsym

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dlsym.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-dlsym-1.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • The visibility of symbols loaded in dependent shared libraries or present in the main executable is system dependent.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.9 Functions in <endian.h>

Next: , Up: Functions in <endian.h>   [Contents][Index]

10.9.1 be16toh

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/be16toh.html

Documentation:
man be16toh

Gnulib module: endian

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.8, macOS 14, FreeBSD 13.0, NetBSD 7.2, OpenBSD 5.5, Minix 3.1.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <endian.h>   [Contents][Index]

10.9.2 be32toh

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/be32toh.html

Documentation:
man be32toh

Gnulib module: endian

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.8, macOS 14, FreeBSD 13.0, NetBSD 7.2, OpenBSD 5.5, Minix 3.1.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <endian.h>   [Contents][Index]

10.9.3 be64toh

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/be64toh.html

Documentation:
man be64toh

Gnulib module: endian

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.8, macOS 14, FreeBSD 13.0, NetBSD 7.2, OpenBSD 5.5, Minix 3.1.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <endian.h>   [Contents][Index]

10.9.4 htobe16

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/htobe16.html

Documentation:
man htobe16

Gnulib module: endian

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.8, macOS 14, FreeBSD 13.0, NetBSD 7.2, OpenBSD 5.5, Minix 3.1.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <endian.h>   [Contents][Index]

10.9.5 htobe32

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/htobe32.html

Documentation:
man htobe32

Gnulib module: endian

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.8, macOS 14, FreeBSD 13.0, NetBSD 7.2, OpenBSD 5.5, Minix 3.1.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <endian.h>   [Contents][Index]

10.9.6 htobe64

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/htobe64.html

Documentation:
man htobe64

Gnulib module: endian

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.8, macOS 14, FreeBSD 13.0, NetBSD 7.2, OpenBSD 5.5, Minix 3.1.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <endian.h>   [Contents][Index]

10.9.7 htole16

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/htole16.html

Documentation:
man htole16

Gnulib module: endian

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.8, macOS 14, FreeBSD 13.0, NetBSD 7.2, OpenBSD 5.5, Minix 3.1.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <endian.h>   [Contents][Index]

10.9.8 htole32

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/htole32.html

Documentation:
man htole32

Gnulib module: endian

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.8, macOS 14, FreeBSD 13.0, NetBSD 7.2, OpenBSD 5.5, Minix 3.1.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <endian.h>   [Contents][Index]

10.9.9 htole64

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/htole64.html

Documentation:
man htole64

Gnulib module: endian

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.8, macOS 14, FreeBSD 13.0, NetBSD 7.2, OpenBSD 5.5, Minix 3.1.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <endian.h>   [Contents][Index]

10.9.10 le16toh

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/le16toh.html

Documentation:
man le16toh

Gnulib module: endian

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.8, macOS 14, FreeBSD 13.0, NetBSD 7.2, OpenBSD 5.5, Minix 3.1.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <endian.h>   [Contents][Index]

10.9.11 le32toh

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/le32toh.html

Documentation:
man le32toh

Gnulib module: endian

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.8, macOS 14, FreeBSD 13.0, NetBSD 7.2, OpenBSD 5.5, Minix 3.1.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Previous: , Up: Functions in <endian.h>   [Contents][Index]

10.9.12 le64toh

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/le64toh.html

Documentation:
man le64toh

Gnulib module: endian

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.8, macOS 14, FreeBSD 13.0, NetBSD 7.2, OpenBSD 5.5, Minix 3.1.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.10 Functions in <errno.h>

Up: Functions in <errno.h>   [Contents][Index]

10.10.1 errno

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/errno.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • On Windows, the socket functions don’t set errno; their error code is available through WSAGetLastError() instead.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.11 Functions in <fcntl.h>

Next: , Up: Functions in <fcntl.h>   [Contents][Index]

10.11.1 creat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/creat.html

Gnulib module: creat

Portability problems fixed by Gnulib:

  • This function does not support modes with execution bits (such as 0700) on some platforms: MSVC 14.
  • On platforms where off_t is a 32-bit type, creat may not work correctly with files 2 GiB and larger. See Large File Support.
  • This function does not fail when the file name argument ends in a slash and (without the slash) names a nonexistent file, on some platforms: FreeBSD 7.2, AIX 7.1, HP-UX 11.31, Solaris 9.

Portability problems not fixed by Gnulib:

  • On Windows, this function returns a file handle in O_TEXT mode. If you need a file handle in O_BINARY mode, you need to use the function open instead.

Next: , Previous: , Up: Functions in <fcntl.h>   [Contents][Index]

10.11.2 fcntl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fcntl.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fcntl-3.html

Gnulib module: fcntl

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • This function does not support F_DUPFD_CLOEXEC on some platforms: glibc with Linux kernels before 2.6.24, Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, AIX 7.1, HP-UX 11, Solaris 11 2010-11, Cygwin 1.7.1. Note that the gnulib replacement code is functional but not atomic.
  • The F_DUPFD_CLOEXEC action of this function does not set the FD_CLOEXEC flag on some platforms: NetBSD 10.0.
  • The F_DUPFD_CLOEXEC action of this function sets the FD_CLOEXEC flag on the wrong file descriptor on some platforms: Haiku.
  • The F_DUPFD action of this function does not reject out-of-range targets properly on some platforms: AIX 7.1, Cygwin 1.5.x, Haiku.
  • The F_DUPFD action of this function mistakenly clears FD_CLOEXEC on the source descriptor on some platforms: Haiku.

Portability problems not fixed by Gnulib:

  • The replacement function does not support F_SETFD, F_GETFL, F_SETFL, F_GETOWN, F_SETOWN, F_GETLK, F_SETLK, and F_SETLKW on some platforms: mingw, MSVC 14.
  • When a file does not support locking (such as on an NFS file system that does not support file locking), calls with F_SETLK and F_SETLKW fail with errno set to different values on different systems: EINVAL on OpenIndiana (as suggested by the POSIX 1003.1-2017 fcntl specification), ENOLCK on GNU/Linux, and EOPNOTSUPP on FreeBSD.

Next: , Previous: , Up: Functions in <fcntl.h>   [Contents][Index]

10.11.3 open

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/open.html

Gnulib module: open, fchdir

Portability problems fixed by the Gnulib module open:

  • Some platforms do not support O_CLOEXEC: Mac OS X 10.6, FreeBSD 8.4, NetBSD 5.1, OpenBSD 4.9, Minix 3.1.8, AIX 7.1, HP-UX 11, Solaris 10, Cygwin 1.7.x, mingw, MSVC 14.
  • Some platforms do not support O_DIRECTORY: glibc 2.0, Mac OS X 10.4, FreeBSD 7.4, NetBSD 4.0.1, OpenBSD 4.9, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14.
  • On platforms where off_t is a 32-bit type, open may not work correctly with files 2 GiB and larger. See Large File Support.
  • This function does not fail when the file name argument ends in a slash and (without the slash) names a nonexistent file or a file that is not a directory, on some platforms: macOS 14, FreeBSD 7.2, AIX 7.1, HP-UX 11.00, Solaris 9.
  • This function does not support the O_NONBLOCK flag when it is defined by the gnulib module nonblocking on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), this function does usually not recognize the /dev/null filename.

Portability problems fixed by the Gnulib module fchdir:

  • On Windows platforms (excluding Cygwin), this function fails to open a read-only descriptor for directories.

Portability problems not fixed by Gnulib:

  • The Gnulib replacement for O_CLOEXEC is not atomic, and so is not safe in the presence of multiple threads or signal handlers.
  • The Gnulib replacement for O_SEARCH may require read access instead of search/execute access.
  • On some platforms, O_SEARCH may reject directories where you have search access even though O_SEARCH is not replaced: macOS 12.6.
  • When the file does not exist, POSIX says the behavior of O_CREAT | O_DIRECTORY is unspecified. Most platforms fail with EINVAL in this case. However, in Linux kernels 6.3 and earlier, this function creates a regular file and then either returns successfully (Linux kernel 5.6 and earlier) or fails with ENOTDIR (Linux kernels 5.7–6.3).
  • open ("symlink", O_CREAT ...) fails when the argument points to a nonexistent file in an existing directory on some platforms: Haiku.
  • open ("symlink", O_NOFOLLOW ...) fails with errno set to EMLINK instead of the POSIX-required ELOOP on some platforms: FreeBSD 14.2.
  • open ("symlink", O_NOFOLLOW ...) fails with errno set to EFTYPE instead of the POSIX-required ELOOP on some platforms: NetBSD 10.0.
  • open ("directory", O_CREAT ...) fails with errno set to EINVAL instead of the POSIX-required EISDIR on some platforms: Solaris 11.4.
  • open ("fifo", O_DIRECTORY ...) does not fail on some platforms: Haiku.
  • On Windows, this function returns a file handle in O_TEXT mode by default; this means that it translates '\n' to CR/LF by default. Use the O_BINARY flag if you need reliable binary I/O.

Next: , Previous: , Up: Functions in <fcntl.h>   [Contents][Index]

10.11.4 openat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/openat.html

Gnulib module: openat

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.5.x, mingw, MSVC 14. But the replacement function is not safe to be used in libraries and is not thread-safe.
  • Some platforms do not support O_CLOEXEC: AIX 7.1, Solaris 10.
  • Some platforms do not support O_DIRECTORY: glibc 2.0, Mac OS X 10.4, FreeBSD 7.4, NetBSD 4.0.1, OpenBSD 4.9, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14.
  • On platforms where off_t is a 32-bit type, open may not work correctly with files 2 GiB and larger. See Large File Support.
  • This function does not fail when the file name argument ends in a slash and (without the slash) names a nonexistent file or a file that is not a directory, on some platforms: Solaris 9.

Portability problems not fixed by Gnulib:

  • The Gnulib replacement for O_CLOEXEC is not atomic, and so is not safe in the presence of multiple threads or signal handlers.
  • The Gnulib replacement for O_SEARCH may require read access instead of search/execute access.
  • On some platforms, O_SEARCH may reject directories where you have search access even though O_SEARCH is not replaced: macOS 12.6.
  • When the file does not exist, POSIX says the behavior of O_CREAT | O_DIRECTORY is unspecified. Most platforms fail with EINVAL in this case. However, in Linux kernels 6.3 and earlier, this function creates a regular file and then either returns successfully (Linux kernel 5.6 and earlier) or fails with ENOTDIR (Linux kernels 5.7–6.3).
  • openat (fd, "symlink", O_NOFOLLOW ...) fails with errno set to EMLINK instead of the POSIX-required ELOOP on some platforms: FreeBSD 10.1.
  • openat (fd, "symlink", O_NOFOLLOW ...) fails with errno set to EFTYPE instead of the POSIX-required ELOOP on some platforms: NetBSD 6.1.
  • openat (fd, "directory", O_CREAT ...) fails with errno set to EINVAL instead of the POSIX-required EISDIR on some platforms: Solaris 11.4.

Next: , Previous: , Up: Functions in <fcntl.h>   [Contents][Index]

10.11.5 posix_fadvise

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_fadvise.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, this function may not work correctly across the entire data range of files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11.23, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 4.4.

Previous: , Up: Functions in <fcntl.h>   [Contents][Index]

10.11.6 posix_fallocate

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_fallocate.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, this function may not work correctly across the entire data range of files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 4.4.
  • POSIX specifies that EINVAL should be returned when the file system doesn’t support the allocation operation directly. glibc however emulates the file system allocation with writes where unsupported, and apps have depended on that long term implementation. This is both inefficient, and as of glibc 2.21 at least, buggy on certain NFS setups.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.12 Functions in <fenv.h>

Next: , Up: Functions in <fenv.h>   [Contents][Index]

10.12.1 feclearexcept

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/feclearexcept.html

Gnulib module: fenv-exceptions-tracking-c99

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, Cygwin 1.7.7, MSVC 9, Android 4.4.
  • This function is broken on some platforms: OpenBSD 7.4/mips64, Minix 3.3/i386.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <fenv.h>   [Contents][Index]

10.12.2 fegetenv

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fegetenv.html

Gnulib module: fenv-environment

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, Cygwin 1.7.7, MSVC 9, Android 4.4.
  • This function clears all exception trap bits on some platforms: glibc 2.19/x86_64, Mac OS X 10.5/i386, Mac OS X 10.5/x86_64.
  • This function does not save the exception trap bits on some platforms: AIX 7.3.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <fenv.h>   [Contents][Index]

10.12.3 fegetexceptflag

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fegetexceptflag.html

Gnulib module: fenv-exceptions-state-c99

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, Cygwin 1.7.7, MSVC 9, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <fenv.h>   [Contents][Index]

10.12.4 fegetmode

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Control-Functions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <fenv.h>   [Contents][Index]

10.12.5 fegetround

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fegetround.html

Gnulib module: fenv-rounding

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, AIX 5.1, Solaris 9, Cygwin 1.7.7, MSVC 9, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <fenv.h>   [Contents][Index]

10.12.6 feholdexcept

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/feholdexcept.html

Gnulib module: fenv-environment

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, AIX 5.1, Solaris 9, Cygwin 1.7.7, MSVC 9, Android 4.4.
  • This function does not work on some platforms: glibc 2.5, FreeBSD 12.2/arm64.
  • This function does not save the exception trap bits on some platforms: AIX 7.3.
  • This function does not clear the exception trap bits on some platforms: musl libc, mingw.
  • This function may fail on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <fenv.h>   [Contents][Index]

10.12.7 feraiseexcept

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/feraiseexcept.html

Gnulib module: fenv-exceptions-tracking-c99

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, Cygwin 1.7.7, MSVC 9, Android 4.4.
  • This function does not detect failures on glibc 2.19/arm.
  • This function does not trigger traps on Cygwin 3.4.x/x86_64.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <fenv.h>   [Contents][Index]

10.12.8 fesetenv

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fesetenv.html

Gnulib module: fenv-environment

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, Cygwin 1.7.7, MSVC 9, Android 4.4.
  • This function does not work on some platforms: FreeBSD 12.2/arm64, mingw 13.
  • This function does not restore the floating-point exception trap bits on some platforms: musl libc/i386, musl libc/x86_64, AIX 7.3, Solaris 10 and 11, MSVC 14.
  • The macro FE_DFL_ENV cannot be used because it leads to a link error on some platforms: NetBSD 10.0/hppa, NetBSD 10.0/sparc, Cygwin 2.9.0.
  • This function, when called with FE_DFL_ENV argument, has no effect on the x86 mxcsr register and thus on floating-point operations performed in the SSE unit on some platforms: mingw 10.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <fenv.h>   [Contents][Index]

10.12.9 fesetexcept

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Status-bit-operations.html.

Gnulib module: fenv-exceptions-tracking-c23

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function triggers floating-point exception traps although it shouldn’t, on glibc 2.37/i386, glibc 2.37/powerpc.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <fenv.h>   [Contents][Index]

10.12.10 fesetexceptflag

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fesetexceptflag.html

Gnulib module: fenv-exceptions-state-c99

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, Cygwin 1.7.7, MSVC 9, Android 4.4.
  • This function triggers floating-point exception traps although it shouldn’t, on glibc 2.37/i386, glibc 2.37/x86_64, glibc 2.37/powerpc, musl libc, Mac OS X 10.5, Minix 3.3, mingw, Haiku.
  • This function clears too many floating-point exception flags on glibc 2.37/alpha.
  • This function loses the FE_INVALID flag on FreeBSD 14.0/powerpc64, NetBSD 9.3/powerpc.
  • This function is also buggy on AIX 7.3.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <fenv.h>   [Contents][Index]

10.12.11 fesetmode

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Control-Functions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <fenv.h>   [Contents][Index]

10.12.12 fesetround

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fesetround.html

Gnulib module: fenv-rounding

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, AIX 5.1, Solaris 9, Cygwin 1.7.7, MSVC 9, Android 4.4.
  • This function does not work on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

  • The rounding mode has no effect on long double operations on some platforms: Android/arm64, FreeBSD/arm64, NetBSD/sparc64, OpenBSD/arm64, OpenBSD/mips64.

Next: , Previous: , Up: Functions in <fenv.h>   [Contents][Index]

10.12.13 fetestexcept

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fetestexcept.html

Gnulib module: fenv-exceptions-tracking-c99

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, Cygwin 1.7.7, MSVC 9, Android 4.4.
  • This function clears the floating-point exception trap bits on some platforms: NetBSD 9.3/x86_64.
  • This function is broken on some platforms: Minix 3.3/i386.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <fenv.h>   [Contents][Index]

10.12.14 fetestexceptflag

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Status-bit-operations.html.

Gnulib module: fenv-exceptions-state-c23

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Previous: , Up: Functions in <fenv.h>   [Contents][Index]

10.12.15 feupdateenv

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/feupdateenv.html

Gnulib module: fenv-environment

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, Cygwin 1.7.7, MSVC 14, Android 4.4.
  • This function crashes when given the argument FE_DFL_ENV on some platforms: glibc 2.37/riscv64.
  • This function does not work on some platforms: glibc 2.5/ia64, FreeBSD 12.2/arm64, mingw 13.
  • This function forgets about the currently set floating-point exception flags on some platforms: Mac OS X 10.5/i386, Mac OS X 10.5/x86_64.
  • This function does not restore the floating-point exception trap bits on some platforms: musl libc/i386, musl libc/x86_64, AIX 7.3, Solaris 10 and 11, mingw 10.
  • This function does not trigger traps on glibc 2.37/hppa, musl libc/s390x, NetBSD 10.0/powerpc.
  • This function may fail on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.13 Functions in <fmtmsg.h>

Up: Functions in <fmtmsg.h>   [Contents][Index]

10.13.1 fmtmsg

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fmtmsg.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.14 Functions in <fnmatch.h>

Up: Functions in <fnmatch.h>   [Contents][Index]

10.14.1 fnmatch

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fnmatch.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fnmatch-3.html

Documentation:

Gnulib module: fnmatch or fnmatch-gnu

Portability problems fixed by either Gnulib module fnmatch or fnmatch-gnu:

  • This function is missing on some platforms: mingw, MSVC 14.
  • The "?" pattern character fails to match characters outside the single-byte range on some platforms: NetBSD 10.0, Android 13.
  • The "?" pattern character fails to match characters outside the Unicode BMP on some platforms: Solaris 10, Cygwin 3.4.6, MSVC, 32-bit AIX.
  • In the pattern, negated character ranges (such as [!a-z]) are not supported on some platforms: Solaris 11.4.
  • In the pattern, character classes (such as [:alnum:]) inside bracket expressions are not supported on some platforms: FreeBSD 13.2, NetBSD 10.0, Solaris 11 OpenIndiana, Cygwin 3.4.6.
  • In the pattern, character classes (such as [:alnum:]) inside bracket expressions fail to match characters outside the single-byte range on some platforms: Android 13.
  • The character class [:cntrl:] matches the empty string on some platforms: Solaris 11.4.
  • Ranges that start or end with a backslash don’t work right on some platforms: glibc 2.3.3.
  • In the pattern, an opening bracket without closing bracket does not match a literal '[' on some platforms: glibc 2.12, macOS 12.5, NetBSD 10.0.

Portability problems fixed by Gnulib module fnmatch-gnu:

  • This function does not support the flags FNM_LEADING_DIR and FNM_CASEFOLD on some platforms: AIX 7.2, HP-UX 11.31, Solaris 10.
  • The flag FNM_CASEFOLD does not work in many situations on some platforms: NetBSD 10.0.
  • The flag FNM_CASEFOLD does not work for multibyte characters consisting of more than one byte on some platforms: Android 13.
  • This function does not support the flag FNM_EXTMATCH on all non-glibc platforms: musl libc, macOS 12.5, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.2, Minix 3.3, AIX 7.2, HP-UX 11.31, Solaris 11.4, Cygwin 3.4.6, Android 13.
  • This function does not support the flag FNM_FILE_NAME as an alias of FNM_PATHNAME on some platforms: NetBSD 10.0, AIX 7.2, HP-UX 11.31, Solaris 10.

Portability problems not fixed by Gnulib:

Note: Gnulib’s replacement function has some limitations:

  • It does not implement patterns with collating elements (such as "[[.ch.]]") or equivalence classes (such as "[[=a=]]").

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.15 Functions in <ftw.h>

Up: Functions in <ftw.h>   [Contents][Index]

10.15.1 nftw

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/nftw.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, this function may not correctly report the size of files or block devices 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 3.0, Minix 3.1.8, mingw, MSVC 14, Android 4.1.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.16 Functions in <glob.h>

Next: , Up: Functions in <glob.h>   [Contents][Index]

10.16.1 glob

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/glob.html

Gnulib module: glob

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 8.1.
  • This function does not list symbolic links to nonexistent files among the results, on some platforms: glibc 2.26, AIX 7.2, HP-UX 11, Solaris 11.4.
  • On platforms where off_t is a 32-bit type, this function may not work correctly on huge directories 2 GiB and larger. See Large File Support.
  • This function makes a recursive call for every trailing / and every / following a wildcard character on some platforms, which can cause the stack to overflow: glibc 2.42, Cygwin, Android.

Portability problems not fixed by Gnulib:

  • Some platforms may store additional flags in the gl_flags field.

Previous: , Up: Functions in <glob.h>   [Contents][Index]

10.16.2 globfree

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/globfree.html

Gnulib module: glob

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 8.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.17 Functions in <grp.h>

Next: , Up: Functions in <grp.h>   [Contents][Index]

10.17.1 endgrent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/endgrent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: Functions in <grp.h>   [Contents][Index]

10.17.2 getgrent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getgrent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: Functions in <grp.h>   [Contents][Index]

10.17.3 getgrgid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getgrgid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <grp.h>   [Contents][Index]

10.17.4 getgrgid_r

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getgrgid_r.html

Gnulib module: extensions

Portability problems fixed by Gnulib:

  • This function has an incompatible declaration on some platforms: Solaris 11.3 (when _POSIX_PTHREAD_SEMANTICS is not defined).

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 6.0.

Next: , Previous: , Up: Functions in <grp.h>   [Contents][Index]

10.17.5 getgrnam

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getgrnam.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <grp.h>   [Contents][Index]

10.17.6 getgrnam_r

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getgrnam_r.html

Gnulib module: extensions

Portability problems fixed by Gnulib:

  • This function has an incompatible declaration on some platforms: Solaris 11.3 (when _POSIX_PTHREAD_SEMANTICS is not defined).

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 6.0.

Previous: , Up: Functions in <grp.h>   [Contents][Index]

10.17.7 setgrent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setgrent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.18 Functions in <iconv.h>

Next: , Up: Functions in <iconv.h>   [Contents][Index]

10.18.1 iconv

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iconv.html

Gnulib module: iconv

Portability problems fixed by Gnulib:

  • GNU libiconv is not found if installed in $PREFIX/lib.

Portability problems handled by Gnulib (in the sense that HAVE_ICONV does not get defined if the system’s iconv function has this problem):

  • Failures are not distinguishable from successful returns on some platforms: macOS 14.4, AIX 5.1..7.2, Solaris 10.
  • A buffer overrun can occur on some platforms: AIX 6.1..7.1.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 8.1, when GNU libiconv is not installed.
  • This function was not correctly implemented in glibc versions before 2.2.
  • When iconv encounters an input character that is valid but that cannot be converted to the output character set, glibc’s and GNU libiconv’s iconv stop the conversion. Some other implementations put an implementation-defined character into the output buffer. Gnulib provides higher-level facilities striconv and striconveh (wrappers around iconv) that deal with conversion errors in a platform independent way.
  • This function returns a positive return value, instead of zero, when converting from ISO-8859-1 to UTF-8 on HP-UX 11.

Next: , Previous: , Up: Functions in <iconv.h>   [Contents][Index]

10.18.2 iconv_close

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iconv_close.html

Gnulib module: iconv

Portability problems fixed by Gnulib:

  • GNU libiconv is not found if installed in $PREFIX/lib.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 8.1, when GNU libiconv is not installed.

Previous: , Up: Functions in <iconv.h>   [Contents][Index]

10.18.3 iconv_open

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iconv_open.html

Gnulib module: iconv, iconv_open, iconv_open-utf

Portability problems fixed by either Gnulib module iconv or iconv_open:

  • GNU libiconv is not found if installed in $PREFIX/lib.

Portability problems handled by either Gnulib module iconv or iconv_open (in the sense that HAVE_ICONV does not get defined if the system’s iconv_open function has this problem):

  • No converter from EUC-JP to UTF-8 is provided on some platforms: HP-UX 11.

Portability problems fixed by Gnulib module iconv_open:

  • This function recognizes only non-standard aliases for many encodings (not the IANA registered encoding names) on many platforms: AIX 5.1, HP-UX 11, Solaris 11 2010-11, z/OS.

Portability problems fixed by Gnulib module iconv_open-utf:

  • This function does not support the encodings UTF-16BE, UTF-16LE, UTF-32BE, UTF-32LE on many platforms: AIX 5.1, HP-UX 11.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 8.1, when GNU libiconv is not installed.
  • For some encodings A and B, this function cannot convert directly from A to B, although an indirect conversion from A through UTF-8 to B is possible. This occurs on some platforms: Solaris 11 2010-11. Gnulib provides a higher-level facility striconveh (a wrapper around iconv) that deals with this problem.
  • The set of supported encodings and conversions is system dependent.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.19 Functions in <inttypes.h>

Next: , Up: Functions in <inttypes.h>   [Contents][Index]

10.19.1 imaxabs

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/imaxabs.html

Gnulib module: imaxabs

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11.23, Solaris 9, MSVC 9, Android 4.3.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <inttypes.h>   [Contents][Index]

10.19.2 imaxdiv

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/imaxdiv.html

Gnulib module: imaxdiv

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11.23, Solaris 9, MSVC 9, Android 4.3.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <inttypes.h>   [Contents][Index]

10.19.3 strtoimax

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strtoimax.html

Gnulib module: strtoimax

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, Solaris 9, MSVC 9.
  • This function fails on valid input strings on some platforms: AIX 5.1.

Portability problems not fixed by Gnulib:

  • This function is only defined as a macro on some platforms: HP-UX 11.11.
  • If no conversion could be performed, this function sets errno to EINVAL on some platforms. Portable programs should check for no conversion by comparing str to *endptr, not by inspecting errno.

Next: , Previous: , Up: Functions in <inttypes.h>   [Contents][Index]

10.19.4 strtoumax

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strtoumax.html

Gnulib module: strtoumax

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, MSVC 9.

Portability problems not fixed by Gnulib:

  • This function is only defined as a macro on some platforms: HP-UX 11.11.
  • If no conversion could be performed, this function sets errno to EINVAL on some platforms. Portable programs should check for no conversion by comparing str to *endptr, not by inspecting errno.

Next: , Previous: , Up: Functions in <inttypes.h>   [Contents][Index]

10.19.5 wcstoimax

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcstoimax.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11.11, Solaris 9, Cygwin 1.5.x, MSVC 9, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <inttypes.h>   [Contents][Index]

10.19.6 wcstoumax

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcstoumax.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11.11, Solaris 9, Cygwin 1.5.x, MSVC 9, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Previous: , Up: Functions in <inttypes.h>   [Contents][Index]

10.19.7 umaxabs

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on most platforms: glibc 2.42, macOS 15, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.7, Minix, AIX 7.3, HP-UX 11.31, Solaris 11.4, Cygwin, mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.20 Functions in <langinfo.h>

Next: , Up: Functions in <langinfo.h>   [Contents][Index]

10.20.1 nl_langinfo

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/nl_langinfo.html

Gnulib module: nl_langinfo

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 7.1.
  • The constant CODESET is not supported on some platforms: OpenBSD 3.8.
  • The constants ALTMON_1 to ALTMON_12 are not supported on some platforms: glibc 2.26, musl libc, macOS 14, NetBSD 8.0, OpenBSD 7.9, AIX 7.2, HP-UX 11.31, Solaris 11.4, Haiku, Cygwin 2.9.
  • The constants ABALTMON_1 to ABALTMON_12 are not supported on many platforms: glibc 2.42, musl libc, macOS 14, NetBSD 10.0, OpenBSD 7.6, AIX 7.3, HP-UX 11.31, Solaris 11.4, Haiku, Cygwin 3.5.
  • The constants ERA, ERA_D_FMT, ERA_D_T_FMT, ERA_T_FMT, ALT_DIGITS are not supported on some platforms: OpenBSD 7.9.
  • This function is not thread-safe on some platforms: macOS 26, Solaris 11.3.

Portability problems not fixed by Gnulib:

  • On Cygwin 1.5.x, which doesn’t have locales, nl_langinfo(CODESET) always returns "US-ASCII".
  • On Cygwin 1.7.0, only the charset portion of a locale designation is honored.
  • On NetBSD 5.0, in some locales, nl_langinfo(CRNCYSTR) returns the empty string, although the local currency symbol, as returned by localeconv()->currency_symbol, is non-empty.
  • On NetBSD 5.1, in the "C" locale, the results of nl_langinfo(ABMON_1) ... nl_langinfo(ABMON_12) are full month names, not abbreviated month names.

Previous: , Up: Functions in <langinfo.h>   [Contents][Index]

10.20.2 nl_langinfo_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/nl_langinfo_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.21 Functions in <libgen.h>

Next: , Up: Functions in <libgen.h>   [Contents][Index]

10.21.1 basename

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/basename.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-basename-3.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • glibc and Android have two different functions basename: the POSIX version and the GNU version.
  • basename assumes file names in POSIX syntax; it does not work with file names in Windows syntax.

The Gnulib module basename-lgpl provides similar API, with a function last_component, that also works with Windows file names.

Previous: , Up: Functions in <libgen.h>   [Contents][Index]

10.21.2 dirname

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dirname.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • dirname assumes file names in POSIX syntax; it does not work with file names in Windows syntax.

The Gnulib module dirname provides similar API, with functions dir_name and mdir_name, that also works with Windows file names.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.22 Functions in <libintl.h>

Next: , Up: Functions in <libintl.h>   [Contents][Index]

10.22.1 bind_textdomain_codeset

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/bind_textdomain_codeset.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <libintl.h>   [Contents][Index]

10.22.2 bindtextdomain

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/bindtextdomain.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <libintl.h>   [Contents][Index]

10.22.3 dcgettext

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dcgettext.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function does not treat a LANGUAGE environment variable with an empty value like an unset LANGUAGE environment variable on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <libintl.h>   [Contents][Index]

10.22.4 dcgettext_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dcgettext_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.42, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <libintl.h>   [Contents][Index]

10.22.5 dcngettext

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dcngettext.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function does not treat a LANGUAGE environment variable with an empty value like an unset LANGUAGE environment variable on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <libintl.h>   [Contents][Index]

10.22.6 dcngettext_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dcngettext_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.41, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <libintl.h>   [Contents][Index]

10.22.7 dgettext

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dgettext.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function does not treat a LANGUAGE environment variable with an empty value like an unset LANGUAGE environment variable on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <libintl.h>   [Contents][Index]

10.22.8 dgettext_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dgettext_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.42, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <libintl.h>   [Contents][Index]

10.22.9 dngettext

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dngettext.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function does not treat a LANGUAGE environment variable with an empty value like an unset LANGUAGE environment variable on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <libintl.h>   [Contents][Index]

10.22.10 dngettext_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dngettext_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.42, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <libintl.h>   [Contents][Index]

10.22.11 gettext

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/gettext.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function does not treat a LANGUAGE environment variable with an empty value like an unset LANGUAGE environment variable on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <libintl.h>   [Contents][Index]

10.22.12 gettext_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/gettext_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.42, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <libintl.h>   [Contents][Index]

10.22.13 ngettext

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ngettext.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function does not treat a LANGUAGE environment variable with an empty value like an unset LANGUAGE environment variable on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <libintl.h>   [Contents][Index]

10.22.14 ngettext_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ngettext_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.42, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.

Previous: , Up: Functions in <libintl.h>   [Contents][Index]

10.22.15 textdomain

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/textdomain.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.23 Functions in <locale.h>

Next: , Up: Functions in <locale.h>   [Contents][Index]

10.23.1 duplocale

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/duplocale.html

Gnulib module: duplocale

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 6.1, OpenBSD 6.1, Minix 3.1.8, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 4.4.
  • This function is useless because the locale_t type is not defined on some platforms: z/OS.
  • The argument LC_GLOBAL_LOCALE is not supported on some platforms: glibc 2.11, AIX 7.1.
  • With the argument LC_GLOBAL_LOCALE, this function returns a wrong result on some platforms: NetBSD 7.1.

Portability problems not fixed by Gnulib:

  • With the argument LC_GLOBAL_LOCALE, this function returns a wrong result on some platforms: Haiku.

Next: , Previous: , Up: Functions in <locale.h>   [Contents][Index]

10.23.2 freelocale

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/freelocale.html

Gnulib module: freelocale

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 6.1, OpenBSD 6.1, Minix 3.1.8, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 4.4.
  • This function is useless because the locale_t type is not defined on some platforms: z/OS.

Portability problems not fixed by Gnulib:

  • This function’s return type is int instead of void on macOS.
  • This function may cause crashes in subsequent newlocale invocations on some platforms: Haiku.

Next: , Previous: , Up: Functions in <locale.h>   [Contents][Index]

10.23.3 getlocalename_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getlocalename_l.html

Gnulib module: getlocalename_l-simple

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.42, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.x, mingw, MSVC 14, Android 9.0. But the gnulib replacement supports only a single locale category: the argument LC_ALL is unsupported.
  • This function returns an invalid pointer when the second argument is LC_GLOBAL_LOCALE, on some platforms: Cygwin 3.6.0.
  • This function returns "POSIX" instead of "C" on some platforms: Haiku.

Portability problems not fixed by Gnulib:

  • This function supports only a single locale category, i.e. the argument LC_ALL is unsupported, on some platforms: Cygwin 3.6.0.
  • This function always returns "C" when the first argument is LC_COLLATE on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <locale.h>   [Contents][Index]

10.23.4 localeconv

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/localeconv.html

Gnulib module: localeconv

Portability problems fixed by Gnulib:

  • The struct lconv type does not contain any members on some platforms: Android up to 2014.
  • The struct lconv type does not contain the members int_p_cs_precedes, int_p_sign_posn, int_p_sep_by_space, int_n_cs_precedes, int_n_sign_posn, int_n_sep_by_space on some platforms: glibc, OpenBSD 4.9, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14.
  • The values of fields of struct lconv of type char are -1 instead of CHAR_MAX on some platforms: mingw.

Portability problems not fixed by Gnulib:

Note: The return type of the localeconv function is struct lconv * in POSIX, with the constraint that “The application shall not modify the structure to which the return value points.” The Gnulib-overridden localeconv function has a return type of const struct lconv *. This helps detecting code that attempts to write into that structure.

Next: , Previous: , Up: Functions in <locale.h>   [Contents][Index]

10.23.5 newlocale

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/newlocale.html

Gnulib module: newlocale

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 6.1, OpenBSD 6.1, Minix 3.1.8, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 4.4.
  • This function is useless because the locale_t type is not defined on some platforms: z/OS.
  • When the third argument is NULL, this function uses locale category data from the current locale instead of from the "C" locale on some platforms: macOS, NetBSD 10.0, Solaris 11 OpenIndiana.
  • When the second argument is an invalid or unsupported locale name, this function uses the "C" locale instead of failing on some platforms: NetBSD 10.0.

Portability problems not fixed by Gnulib:

  • This function is useless because the locale_t type contains basically no information on some platforms: OpenBSD 6.3.

Next: , Previous: , Up: Functions in <locale.h>   [Contents][Index]

10.23.6 setlocale

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setlocale.html

Gnulib module: setlocale, setlocale-null

Portability problems fixed by Gnulib module setlocale:

  • On Windows platforms (excluding Cygwin), setlocale(category,"") and setlocale(category,NULL) both ignore the environment variables LC_ALL, category, and LANG.
  • On Windows platforms (excluding Cygwin) and Cygwin 1.5.x, setlocale(LC_ALL,name) succeeds and sets the LC_CTYPE category to ‘C’ when it does not support the encoding, instead of failing.
  • On Windows platforms (excluding Cygwin), setlocale understands different locale names, that are not based on ISO 639 language names and ISO 3166 country names.
  • On Android 5.0 and newer, setting any category other than LC_CTYPE of the global locale affects the LC_CTYPE category as well.
  • On Android < 5.0, which doesn’t have locales, the setlocale function always fails. The replacement, however, supports only the locale names "C" and "POSIX".

Portability problems fixed by Gnulib module setlocale or setlocale-null:

  • Invocations of setlocale (..., NULL) are not thread-safe on some platforms: musl libc, macOS, FreeBSD, NetBSD, OpenBSD, AIX, Haiku, Cygwin. To make these invocations thread-safe, you need the Gnulib module setlocale, or you need to change the code to invoke setlocale_null or setlocale_null_r instead.

Portability problems not fixed by Gnulib:

  • On Cygwin 1.5.x, which doesn’t have locales, setlocale(LC_ALL,NULL) always returns "C".
  • On Cygwin 1.7.0, only the charset portion of a locale designation is honored.
  • On OpenBSD, setlocale(LC_ALL,"") will only update categories that are deemed appropriate for the LC_ALL environment value, even if there are other categories set to different values in the environment. In addition any value is accepted for LC_CTYPE, and so NULL is never returned to indicate a failure to set locale. To verify category values, each category must be set individually with setlocale(LC_COLLATE,"") etc.
  • On Android 5.0 and newer, the default locale (i.e. the locale in use when setlocale was not called) is the "C.UTF-8" locale, not the "C" locale. Additionally, a setlocale call that is meant to set the "C" or "POSIX" locale actually sets an equivalent of the "C.UTF-8" locale.

Note: The return type of the setlocale function is char * in POSIX, with the constraint that “The application shall not modify the string returned.” The Gnulib-overridden setlocale function has a return type of const char *. This helps detecting code that attempts to write into that string.

Note: The names of locales with UTF-8 encoding are platform dependent:

  • On most platforms, they follow the naming scheme ‘ll_CC.UTF-8’. Here ‘ll’ is an ISO 639 two-letter language code, and ‘CC’ is an ISO 3166 two-letter country code. For example, ‘en_US.UTF-8’ (this locale exists on nearly all systems), ‘fr_FR.UTF-8’, and similar.
  • On native Windows with mingw, UTF-8 locales are not supported.
  • On native Windows with MSVC (version 14 or newer, and with the -MD option in CFLAGS), they follow the naming scheme ‘language_country.65001’ or, equivalently, ‘language_country.utf8’, where ‘language’ is a language name in English and ‘country’ is a country name in English. For example ‘English_United States.65001’ (yes, with a space in it!) or ‘French_France.65001’.

Previous: , Up: Functions in <locale.h>   [Contents][Index]

10.23.7 uselocale

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/uselocale.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 10.0, OpenBSD 6.1, Minix 3.1.8, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android API level 20.
  • This function is not documented and leads to crashes in subsequent setlocale invocations on some platforms: AIX 7.2.
  • This function is useless because the locale_t type is not defined on some platforms: z/OS.
  • This function is useless because the locale_t type contains basically no information on some platforms: OpenBSD 7.4.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.24 Functions in <math.h>

Next: , Up: Functions in <math.h>   [Contents][Index]

10.24.1 acos

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/acos.html

Gnulib module: acos

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.2 acosf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/acosf.html

Gnulib module: acosf

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.3 acosh

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/acosh.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.4 acoshf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/acoshf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.5 acoshl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/acoshl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 4.4.
  • This function produces results which are accurate to only 16 digits on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.6 acosl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/acosl.html

Gnulib module: acosl

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, Android 4.4.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

  • This function produces results which are accurate to only 16 digits on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.7 acospi

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.8

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.8 acospif

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.8

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.9 acospil

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.8

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.10 asin

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/asin.html

Gnulib module: asin

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.11 asinf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/asinf.html

Gnulib module: asinf

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.12 asinh

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/asinh.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.13 asinhf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/asinhf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.14 asinhl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/asinhl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 4.4.
  • This function produces results which are accurate to only 16 digits on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.15 asinl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/asinl.html

Gnulib module: asinl

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, Android 4.4.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

  • This function produces results which are accurate to only 16 digits on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.16 asinpi

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.9

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.17 asinpif

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.9

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.18 asinpil

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.9

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.19 atan

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atan.html

Gnulib module: atan

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.20 atan2

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atan2.html

Gnulib module: atan2

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.21 atan2f

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atan2f.html

Gnulib module: atan2f

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.22 atan2l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atan2l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, Android 4.4.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.
  • This function produces results which are accurate to only 16 digits on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.23 atan2pi

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.11

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.24 atan2pif

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.11

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.25 atan2pil

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.11

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.26 atanf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atanf.html

Gnulib module: atanf

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.27 atanh

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atanh.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.28 atanhf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atanhf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.29 atanhl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atanhl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 4.4.
  • This function produces results which are accurate to only 16 digits on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.30 atanl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atanl.html

Gnulib module: atanl

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, Android 4.4.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

  • This function produces results which are accurate to only 16 digits on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.31 atanpi

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.10

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.32 atanpif

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.10

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.33 atanpil

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.10

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.34 canonicalize

Documentation:
https://www.gnu.org/software/libc/manual/html_node/FP-Bit-Twiddling.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.35 canonicalizef

Documentation:
https://www.gnu.org/software/libc/manual/html_node/FP-Bit-Twiddling.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.36 canonicalizel

Documentation:
https://www.gnu.org/software/libc/manual/html_node/FP-Bit-Twiddling.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.37 cbrt

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cbrt.html

Gnulib module: cbrt or cbrt-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, MSVC 9.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.38 cbrtf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cbrtf.html

Gnulib module: cbrtf or cbrtf-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9, MSVC 9.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.39 cbrtl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cbrtl.html

Gnulib module: cbrtl or cbrtl-ieee

Portability problems fixed by either Gnulib module cbrtl or cbrtl-ieee

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9, Android 4.4.
  • This function produces grossly wrong results on some platforms: OpenBSD 5.1/SPARC.

Portability problems fixed by Gnulib module cbrtl-ieee:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.40 ceil

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ceil.html

Gnulib module: ceil or ceil-ieee

Portability problems fixed by either Gnulib module ceil or ceil-ieee:

Portability problems fixed by Gnulib module ceil-ieee:

  • This function returns a positive zero for an argument between −1 and 0 on some platforms: AIX 7.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.41 ceilf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ceilf.html

Gnulib module: ceilf or ceilf-ieee

Portability problems fixed by either Gnulib module ceilf or ceilf-ieee:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems fixed by Gnulib module ceilf-ieee:

  • This function returns a positive zero for an argument between −1 and 0 on some platforms: macOS 10.5, AIX 7.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.42 ceill

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ceill.html

Gnulib module: ceill or ceill-ieee

Portability problems fixed by either Gnulib module ceill or ceill-ieee:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.
  • This function returns a wrong result for small arguments on some platforms: OpenBSD 5.6.

Portability problems fixed by Gnulib module ceill-ieee:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.43 compoundn

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.7.2

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.41, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.44 compoundnf

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.7.2

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.41, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.45 compoundnl

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.7.2

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.41, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.46 copysign

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/copysign.html

Gnulib module: copysign

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, MSVC 9.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.47 copysignf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/copysignf.html

Gnulib module: copysignf

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9, MSVC 9.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.48 copysignl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/copysignl.html

Gnulib module: copysignl

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.49 cos

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cos.html

Gnulib module: cos

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.50 cosf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cosf.html

Gnulib module: cosf

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.51 cosh

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cosh.html

Gnulib module: cosh

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.52 coshf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/coshf.html

Gnulib module: coshf

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.53 coshl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/coshl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, Android 4.4.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.
  • This function produces results which are accurate to only 16 digits on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.54 cosl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cosl.html

Gnulib module: cosl

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, Android 4.4.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

  • This function produces results which are accurate to only 16 digits on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.55 cospi

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.12

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 13.4, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.56 cospif

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.12

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 13.4, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.57 cospil

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.12

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 13.4, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.58 daddl

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.27, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.59 ddivl

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.27, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.60 dfmal

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.14.5

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.61 dmull

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.27, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.62 dsqrtl

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.14.6

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.63 dsubl

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.27, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.64 erf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/erf.html

Gnulib module: erf

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.65 erfc

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/erfc.html

Gnulib module: erfc

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.66 erfcf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/erfcf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.67 erfcl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/erfcl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 7.1, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 4.4.
  • This function produces results which are accurate to only 16 digits on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.68 erff

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/erff.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.69 erfl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/erfl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 7.1, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 4.4.
  • This function produces results which are accurate to only 16 digits on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.70 exp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/exp.html

Gnulib module: exp or exp-ieee

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.71 exp10

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.6.2

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.72 exp10f

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.6.2

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.73 exp10l

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.6.2

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.74 exp10m1

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.6.3

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.39, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.75 exp10m1f

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.6.3

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.39, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.76 exp10m1l

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.6.3

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.39, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.77 exp2

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/exp2.html

Gnulib module: exp2 or exp2-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, MSVC 9.
  • This function returns grossly wrong results on some platforms: OpenBSD 4.9.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.78 exp2f

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/exp2f.html

Gnulib module: exp2f or exp2f-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.79 exp2l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/exp2l.html

Gnulib module: exp2l or exp2l-ieee

Portability problems fixed by either Gnulib module exp2l or exp2l-ieee:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9, Android 4.4.
  • This function returns Infinity instead of large finite values on some platforms: NetBSD 10.0/i386.
  • This function produces results which are accurate to only 16 digits on some platforms: NetBSD 10.0/x86_64.

Portability problems fixed by Gnulib module exp2l-ieee:

  • This function returns a wrong value for a NaN argument on some platforms: OpenBSD 4.9.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.80 exp2m1

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.6.5

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.39, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.81 exp2m1f

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.6.5

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.39, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.82 exp2m1l

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.6.5

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.39, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.83 expf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/expf.html

Gnulib module: expf or expf-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.84 expl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/expl.html

Gnulib module: expl or expl-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, Android 4.4.
  • This function returns 0.0 for all arguments on some platforms: Haiku 2017.
  • This function returns NaN for small operands on some platforms: OpenBSD 5.4.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.
  • This function produces results which are accurate to only 16 digits on some platforms: musl libc 1.2.2/arm64, musl libc 1.2.2/s390x, NetBSD 10.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.85 expm1

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/expm1.html

Gnulib module: expm1 or expm1-ieee

Portability problems fixed by either Gnulib module expm1 or expm1-ieee:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 9.

Portability problems fixed by Gnulib module expm1-ieee:

  • This function has problems when the argument is minus zero on some platforms: AIX 7.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.86 expm1f

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/expm1f.html

Gnulib module: expm1f or expm1f-ieee

Portability problems fixed by either Gnulib module expm1f or expm1f-ieee:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, mingw, MSVC 9.

Portability problems fixed by Gnulib module expm1f-ieee:

  • This function returns a positive zero for a minus zero argument on some platforms: AIX 7.2.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.87 expm1l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/expm1l.html

Gnulib module: expm1l or expm1l-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 9.3, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 4.4.
  • This function returns 0 instead of small positive values on some platforms: NetBSD 10.0/i386.
  • This function produces results which are accurate to only 16 digits on some platforms: musl libc 1.2.2/arm64, musl libc 1.2.2/s390x, Mac OS X 10.5, NetBSD 10.0/x86_64.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.88 fabs

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fabs.html

Gnulib module: fabs or fabs-ieee

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.89 fabsf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fabsf.html

Gnulib module: fabsf or fabsf-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.90 fabsl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fabsl.html

Gnulib module: fabsl or fabsl-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.91 fadd

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.27, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.92 faddl

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.27, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.93 fdim

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fdim.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.94 fdimf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fdimf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.95 fdiml

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fdiml.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.96 fdiv

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.27, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.97 fdivl

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.27, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.98 ffma

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.14.5

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.99 ffmal

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.14.5

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.100 floor

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/floor.html

Gnulib module: floor or floor-ieee

Portability problems fixed by either Gnulib module floor or floor-ieee:

Portability problems fixed by Gnulib module floor-ieee:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.101 floorf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/floorf.html

Gnulib module: floorf or floorf-ieee

Portability problems fixed by either Gnulib module floorf or floorf-ieee:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems fixed by Gnulib module floorf-ieee:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.102 floorl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/floorl.html

Gnulib module: floorl or floorl-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.103 fma

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fma.html

Gnulib module: fma or fma-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.
  • This function produces wrong results on some platforms: glibc 2.43, Mac OS X 10.5, FreeBSD 6.4/x86, NetBSD 8.0, OpenBSD 7.4/arm64, Cygwin 1.5, mingw.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.104 fmaf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fmaf.html

Gnulib module: fmaf or fmaf-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.
  • This function produces wrong results on some platforms: glibc 2.11, Mac OS X 10.5, FreeBSD 6.4/x86, FreeBSD 12.2/arm, OpenBSD 7.4/arm64, Cygwin 1.5, mingw.

Portability problems not fixed by Gnulib:

  • This function produces wrong results on some platforms: musl libc/powerpc64le when emulated by QEMU 5.0.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.105 fmal

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fmal.html

Gnulib module: fmal or fmal-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9, Android 4.4.
  • This function produces wrong results on some platforms: glibc 2.17, macOS 13/x86_64, FreeBSD 6.4/x86, OpenBSD 7.4/arm64, mingw.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.106 fmax

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fmax.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.107 fmaxf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fmaxf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.108 fmaximum

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.4

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.109 fmaximum_mag

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.6

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.110 fmaximum_magf

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.6

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.111 fmaximum_magl

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.6

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.112 fmaximum_mag_num

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.10

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.113 fmaximum_mag_numf

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.10

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.114 fmaximum_mag_numl

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.10

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.115 fmaximum_num

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.8

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.116 fmaximum_numf

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.8

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.117 fmaximum_numl

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.8

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.118 fmaximumf

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.4

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.119 fmaximuml

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.4

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.120 fmaxl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fmaxl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.121 fmaxmag

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.122 fmaxmagf

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.123 fmaxmagl

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.124 fmin

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fmin.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.125 fminf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fminf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.126 fminimum

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.5

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.127 fminimum_mag

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.7

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.128 fminimum_magf

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.7

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.129 fminimum_magl

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.7

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.130 fminimum_mag_num

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.11

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.131 fminimum_mag_numf

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.11

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.132 fminimum_mag_numl

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.11

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.133 fminimum_num

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.9

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.134 fminimum_numf

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.9

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.135 fminimum_numl

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.9

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.136 fminimumf

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.5

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.137 fminimuml

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.12.5

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.138 fminl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fminl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.139 fminmag

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.140 fminmagf

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.141 fminmagl

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.142 fmod

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fmod.html

Gnulib module: fmod or fmod-ieee

Portability problems fixed by either Gnulib module fmod or fmod-ieee:

Portability problems fixed by Gnulib module fmod-ieee:

  • This function has problems when the first argument is minus zero on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.143 fmodf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fmodf.html

Gnulib module: fmodf or fmodf-ieee

Portability problems fixed by either Gnulib module fmodf or fmodf-ieee:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems fixed by Gnulib module fmodf-ieee:

  • This function has problems when the first argument is minus zero on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.144 fmodl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fmodl.html

Gnulib module: fmodl or fmodl-ieee

Portability problems fixed by either Gnulib module fmodl or fmodl-ieee:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, Android 4.4.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.
  • This function is not declared and does not work on some platforms: AIX 5.1.

Portability problems fixed by Gnulib module fmodl-ieee:

  • This function has problems when the first argument is minus zero on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.145 fmul

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.27, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.146 fmull

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.27, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.147 fpclassify

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fpclassify.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, OpenBSD 7.9, AIX 5.1, Solaris 11.4, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.148 frexp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/frexp.html

Gnulib module: frexp or frexp-ieee

Portability problems fixed by Gnulib:

  • This function does not work on denormalized numbers on some platforms: NetBSD 3.0.
  • This function does not work on negative zero on some platforms: NetBSD 4.99, MSVC 14.
  • This function does not work on infinite numbers on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.149 frexpf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/frexpf.html

Gnulib module: frexpf or frexpf-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.
  • This function does not work on negative zero on some platforms: mingw.
  • This function does not work on infinite numbers on some platforms: mingw.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.150 frexpl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/frexpl.html

Gnulib module: frexpl or frexpl-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, Android 4.4.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.
  • This function does not work on finite numbers on some platforms: AIX 5.1, MSVC 14.
  • This function does not work on denormalized numbers on some platforms: macOS 10.13/i386.
  • This function does not work on infinite numbers on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.151 fromfp

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Rounding-Functions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.152 fromfpf

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Rounding-Functions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.153 fromfpl

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Rounding-Functions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.154 fromfpx

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Rounding-Functions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.155 fromfpxf

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Rounding-Functions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.156 fromfpxl

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Rounding-Functions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.157 fsqrt

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.14.6

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.158 fsqrtl

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.14.6

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.159 fsub

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.27, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.160 fsubl

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Misc-FP-Arithmetic.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.27, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.161 getpayload

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section F.10.13.1

Documentation:
https://www.gnu.org/software/libc/manual/html_node/FP-Bit-Twiddling.html.

Gnulib module: getpayload

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function returns a wrong result for non-NaN arguments on some platforms: glibc 2.31.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.162 getpayloadf

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section F.10.13.1

Documentation:
https://www.gnu.org/software/libc/manual/html_node/FP-Bit-Twiddling.html.

Gnulib module: getpayloadf

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function returns a wrong result for non-NaN arguments on some platforms: glibc 2.31.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.163 getpayloadl

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section F.10.13.1

Documentation:
https://www.gnu.org/software/libc/manual/html_node/FP-Bit-Twiddling.html.

Gnulib module: getpayloadl

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function returns a wrong result for non-NaN arguments on some platforms: glibc 2.31.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.164 hypot

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/hypot.html

Gnulib module: hypot or hypot-ieee

Portability problems fixed by either Gnulib module hypot or hypot-ieee:

Portability problems fixed by Gnulib module hypot-ieee:

  • When the arguments are mixed NaN and Infinity, this function returns a wrong value on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.165 hypotf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/hypotf.html

Gnulib module: hypotf or hypotf-ieee

Portability problems fixed by either Gnulib module hypotf or hypotf-ieee:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 14.
  • This function produces wrong values on some platforms: NetBSD 5.1, OpenBSD 4.9.

Portability problems fixed by Gnulib module hypot-ieee:

  • When the arguments are mixed NaN and Infinity, this function returns a wrong value on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.166 hypotl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/hypotl.html

Gnulib module: hypotl or hypotl-ieee

Portability problems fixed by either Gnulib module hypotl or hypotl-ieee:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 14, Android 4.4.
  • This function produces very imprecise results on some platforms: NetBSD 10.0, OpenBSD 5.1/SPARC.

Portability problems fixed by Gnulib module hypotl-ieee:

  • When the arguments are mixed NaN and Infinity, this function returns a wrong value on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.167 ilogb

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ilogb.html

Gnulib module: ilogb

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, MSVC 9.
  • This function returns a wrong result for a zero argument on some platforms: OpenBSD 6.7, AIX 5.1.
  • This function returns a wrong result for denormalized arguments on some platforms: Mac OS X 10.5 64-bit, AIX 7.1 64-bit.
  • This function returns a wrong result for an infinite argument on some platforms: NetBSD 7.1, OpenBSD 6.7.
  • This function returns a wrong result for a NaN argument on some platforms: NetBSD 7.1, OpenBSD 6.7.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.168 ilogbf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ilogbf.html

Gnulib module: ilogbf

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.
  • This function returns a wrong result for a zero argument on some platforms: OpenBSD 6.7.
  • This function returns a wrong result for an infinite argument on some platforms: NetBSD 7.1, OpenBSD 6.7.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.169 ilogbl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ilogbl.html

Gnulib module: ilogbl

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 7.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9.
  • This function returns a wrong result for a zero argument on some platforms: Cygwin 2.9.
  • This function returns a wrong result for a NaN argument on some platforms: Cygwin 3.4.x.
  • This function returns a wrong result for denormalized arguments on some platforms: AIX 7.1 64-bit, Haiku 2017.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.170 isfinite

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isfinite.html

Gnulib module: isfinite

Portability problems fixed by Gnulib:

  • This macro is missing on some platforms: macOS 14, OpenBSD 7.9, AIX 5.1, Solaris 11.4.
  • This macro incorrectly yields true for some ‘double’ and for some ‘long double’ arguments, on some platforms: Linux/ia64 (NaNs).

Portability problems not fixed by Gnulib:

  • It is implementation-dependent whether isfinite raises an exception given a signaling NaN operand.
  • This macro returns an unspecified result when given noncanonical values such as unnormalized numbers, pseudo-denormals, pseudo-NaNs, pseudo-Infinities, and pseudo-zeroes.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.171 isgreater

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isgreater.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, AIX 5.1, Solaris 11.4, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.172 isgreaterequal

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isgreaterequal.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, AIX 5.1, Solaris 11.4, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.173 isinf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isinf.html

Gnulib module: isinf

Portability problems fixed by Gnulib:

  • This macro is missing on some platforms: AIX 5.1, Solaris 11.4.

Portability problems not fixed by Gnulib:

  • This macro returns an unspecified result when given noncanonical values such as unnormalized numbers, pseudo-denormals, pseudo-NaNs, pseudo-Infinities, and pseudo-zeroes.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.174 isless

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isless.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, AIX 5.1, Solaris 11.4, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.175 islessequal

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/islessequal.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, AIX 5.1, Solaris 11.4, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.176 islessgreater

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/islessgreater.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, AIX 5.1, Solaris 11.4, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.177 isnan

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isnan.html

Gnulib module: isnan

Portability problems fixed by Gnulib:

  • This macro is missing on some platforms: MSVC 9.
  • isnan was introduced with C99 and is thus commonly not present on pre-C99 systems.
  • isnan is not a macro on some platforms: Solaris 11.4.
  • This macro does not work on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

  • This macro returns an unspecified result when given noncanonical values such as unnormalized numbers, pseudo-denormals, pseudo-NaNs, pseudo-Infinities, and pseudo-zeroes.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.178 isnormal

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isnormal.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, OpenBSD 7.9, AIX 5.1, Solaris 11.4, Android 4.4.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.179 isunordered

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isunordered.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, AIX 5.1, Solaris 11.4, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.180 j0

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/j0.html

Gnulib module: j0

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.181 j1

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/j1.html

Gnulib module: j1

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.182 jn

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/jn.html

Gnulib module: jn

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.183 ldexp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ldexp.html

Gnulib module: ldexp or ldexp-ieee

Portability problems fixed by Gnulib:

  • This function produces wrong results on some platforms: OpenBSD 7.3/mips64.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.184 ldexpf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ldexpf.html

Gnulib module: ldexpf or ldexpf-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.185 ldexpl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ldexpl.html

Gnulib module: ldexpl or ldexpl-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.
  • This function has no prototype in <math.h> on some platforms: Mac OS X.
  • This function does not work on finite numbers on some platforms: AIX 5.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.186 lgamma

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lgamma.html

Gnulib module: lgamma

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.187 lgammaf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lgammaf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.188 lgammal

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lgammal.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 9.3, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9, Android 4.4.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.189 llogb

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Exponents-and-Logarithms.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.190 llogbf

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Exponents-and-Logarithms.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.191 llogbl

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Exponents-and-Logarithms.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.192 llrint

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/llrint.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, Cygwin 1.5.x, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.193 llrintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/llrintf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.5.x, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.194 llrintl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/llrintl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 9.3, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.5.x, MSVC 9, Android 4.4.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.195 llround

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/llround.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, Cygwin 1.7.7, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.196 llroundf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/llroundf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.7, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.197 llroundl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/llroundl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 7.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.198 log

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/log.html

Gnulib module: log or log-ieee

Portability problems fixed by either Gnulib module log or log-ieee:

Portability problems fixed by Gnulib module log-ieee:

  • This function returns a wrong value for a negative argument on some platforms: NetBSD 5.1, Solaris 11.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.199 log10

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/log10.html

Gnulib module: log10 or log10-ieee

Portability problems fixed by either Gnulib module log10 or log10-ieee:

Portability problems fixed by Gnulib module log10-ieee:

  • This function returns a wrong value for a negative argument on some platforms: NetBSD 5.1, Solaris 11.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.200 log10f

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/log10f.html

Gnulib module: log10f or log10f-ieee

Portability problems fixed by either Gnulib module log10f or log10f-ieee:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems fixed by Gnulib module log10f-ieee:

  • This function returns a wrong value for a negative argument on some platforms: NetBSD 5.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.201 log10l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/log10l.html

Gnulib module: log10l or log10l-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, Android 4.4.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.
  • This function is not declared and does not work on some platforms: AIX 5.1.
  • This function produces results which are accurate to only 16 digits on some platforms: musl libc 1.2.2/arm64, musl libc 1.2.2/s390x, NetBSD 10.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.202 log10p1

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.6.13

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.39, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.203 log10p1f

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.6.13

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.39, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.204 log10p1l

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.6.13

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.39, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.205 log1p

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/log1p.html

Gnulib module: log1p or log1p-ieee

Portability problems fixed by either Gnulib module log1p or log1p-ieee:

  • This function is missing on some platforms: Minix 3.1.8, MSVC 9.

Portability problems fixed by Gnulib module log1p-ieee:

  • This function has problems when the argument is minus zero on some platforms: AIX 7.1, HP-UX 11.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.206 log1pf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/log1pf.html

Gnulib module: log1pf or log1pf-ieee

Portability problems fixed by either Gnulib module log1pf or log1pf-ieee:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.

Portability problems fixed by Gnulib module log1pf-ieee:

  • This function has problems when the argument is minus zero on some platforms: OpenBSD 4.9, AIX 7.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.207 log1pl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/log1pl.html

Gnulib module: log1pl or log1pl-ieee

Portability problems fixed by either Gnulib module log1pl or log1pl-ieee:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 9.3, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9, Android 4.4.
  • This function produces results which are accurate to only 16 digits on some platforms: musl libc 1.2.2/arm64, musl libc 1.2.2/s390x, NetBSD 10.0.

Portability problems fixed by Gnulib module log1pl-ieee:

  • This function has problems when the argument is minus zero on some platforms: AIX 7.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.208 log2

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/log2.html

Gnulib module: log2 or log2-ieee

Portability problems fixed by either Gnulib module log2 or log2-ieee:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, MSVC 9, Android 4.2.
  • This function is only provided as a macro on some platforms: Cygwin 1.5.x.
  • This function returns slightly wrong values for exact powers of 2 on some platforms: Cygwin 1.7.9.

Portability problems fixed by Gnulib module log2-ieee:

  • This function returns a wrong value for a negative argument on some platforms: NetBSD 5.1, Solaris 10/x86_64.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.209 log2f

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/log2f.html

Gnulib module: log2f or log2f-ieee

Portability problems fixed by either Gnulib module log2f or log2f-ieee:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, MSVC 9, Android 4.2.
  • This function is only provided as a macro on some platforms: Cygwin 1.5.x.
  • This function returns slightly wrong values for exact powers of 2 on some platforms: Cygwin 1.7.9.

Portability problems fixed by Gnulib module log2f-ieee:

  • This function returns a wrong value for a negative argument on some platforms: NetBSD 5.1, Solaris 10/x86_64.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.210 log2l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/log2l.html

Gnulib module: log2l or log2l-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 9.3, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9, Android 4.2.
  • This function produces results which are accurate to only 16 digits on some platforms: musl libc 1.2.2/arm64, musl libc 1.2.2/s390x.
  • This function returns Infinity for some large finite arguments on some platforms: musl libc 1.2.2/arm64, musl libc 1.2.2/s390x, NetBSD 10.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.211 log2p1

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.6.16

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.39, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.212 log2p1f

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.6.16

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.39, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.213 log2p1l

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.6.16

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.39, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.214 logb

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/logb.html

Gnulib module: logb or logb-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, MSVC 9.
  • This function is missing a declaration on some platforms: Cygwin 1.5.x.
  • This function produces wrong results for subnormal numbers on some platforms: glibc 2.17/ppc, glibc 2.7/sparc, glibc 2.7/hppa, Solaris 11.4, Cygwin 1.5.x.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.215 logbf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/logbf.html

Gnulib module: logbf or logbf-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.
  • This function produces wrong results for subnormal numbers on some platforms: glibc 2.11/ppc, glibc 2.7/sparc, glibc 2.7/hppa, Solaris 11.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.216 logbl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/logbl.html

Gnulib module: logbl or logbl-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9, Android 4.2.
  • This function goes into an endless loop for arguments such as 1.6810515715560467531313389086608763012990396724232e-4932L on some platforms: OpenBSD 7.3/mips64.
  • This function produces wrong results for subnormal numbers on some platforms: glibc 2.11/powerpc, glibc 2.7/sparc, glibc 2.7/hppa, Solaris 11.4, glibc 2.23/powerpc64le.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.217 logf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/logf.html

Gnulib module: logf or logf-ieee

Portability problems fixed by either Gnulib module logf or logf-ieee:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems fixed by Gnulib module logf-ieee:

  • This function returns a wrong value for a negative argument on some platforms: NetBSD 5.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.218 logl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/logl.html

Gnulib module: logl or logl-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, Android 4.4.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.
  • This function returns wrong results on some platforms: glibc 2.7 on Linux/SPARC64.
  • This function produces results which are accurate to only 16 digits on some platforms: musl libc 1.2.2/arm64, musl libc 1.2.2/s390x, NetBSD 10.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.219 logp1

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.6.14

Gnulib module: logp1

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.39, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.220 logp1f

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.6.14

Gnulib module: logp1f

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.39, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.221 logp1l

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.6.14

Gnulib module: logp1l

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.39, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.222 lrint

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lrint.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.223 lrintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lrintf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.224 lrintl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lrintl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 9.3, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.5.x, MSVC 9, Android 4.4.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.225 lround

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lround.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.226 lroundf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lroundf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.227 lroundl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lroundl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 7.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.228 math_errhandling

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.1

Documentation:
man math_error

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This macro is missing on some platforms: NetBSD 10.0, mingw.
  • This macro does not describe the error behaviour of elementary arithmetic operations (+, -, *, /) and of mathematical operations for which the compiler emits inline code (such as sqrt on some CPUs).
  • This macro does not describe the error behaviour of functions such as strtod.
  • For mathematical operations in general, it is a safer bet to look at the exceptions set in the floating-point environment (by calling feclearexcept (FE_ALL_EXCEPT) before the operation and fetestexcept after the operation), regardless of math_errhandling.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.229 modf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/modf.html

Gnulib module: modf or modf-ieee

Portability problems fixed by either Gnulib module modf or modf-ieee:

Portability problems fixed by Gnulib module modf-ieee:

  • This function has problems with a NaN argument on some platforms: NetBSD 5.1, Cygwin.
  • This function has problems with infinite arguments on some platforms: FreeBSD 6.4, OpenBSD 7.3, mingw with MSVCRT.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.230 modff

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/modff.html

Gnulib module: modff or modff-ieee

Portability problems fixed by either Gnulib module modff or modff-ieee:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11.
  • This function is only defined as a buggy macro with arguments on some platforms: MSVC 14.

Portability problems fixed by Gnulib module modff-ieee:

  • This function has problems with a NaN argument on some platforms: NetBSD 5.1, OpenBSD 7.9, Solaris 9, Cygwin.
  • This function has problems with infinite arguments on some platforms: mingw with MSVCRT.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.231 modfl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/modfl.html

Gnulib module: modfl or modfl-ieee

Portability problems fixed by either Gnulib module modfl or modfl-ieee:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, Android 4.4.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.
  • This function produces wrong results on some platforms: NetBSD 10.0/arm64.

Portability problems fixed by Gnulib module modfl-ieee:

  • This function has problems with infinite arguments on some platforms: mingw.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.232 nan

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/nan.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.233 nanf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/nanf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.234 nanl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/nanl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9, Android 3.1.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.235 nearbyint

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/nearbyint.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, AIX 5.1, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.236 nearbyintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/nearbyintf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.237 nearbyintl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/nearbyintl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9, Android 4.4.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.238 nextafter

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/nextafter.html

Gnulib module: nextafter

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.239 nextafterf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/nextafterf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.240 nextafterl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/nextafterl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 4.4.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.241 nextdown

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.23, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.242 nextdownf

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.23, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.243 nextdownl

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.23, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.244 nexttoward

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/nexttoward.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 4.2.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.245 nexttowardf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/nexttowardf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.246 nexttowardl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/nexttowardl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 8.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 9, Android 4.2.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.247 nextup

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.23, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.248 nextupf

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.23, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.249 nextupl

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.23, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.250 pow

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pow.html

Gnulib module: pow

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.251 powf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/powf.html

Gnulib module: powf

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 9.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.252 powl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/powl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, Android 4.4.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.
  • This function produces results which are accurate to only 16 digits on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.253 pown

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.7.6

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all platforms: glibc 2.41, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.254 pownf

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.7.6

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all platforms: glibc 2.41, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.255 pownl

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.7.6

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all platforms: glibc 2.41, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.256 powr

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.7.7

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all platforms: glibc 2.41, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.257 powrf

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.7.7

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all platforms: glibc 2.41, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.258 powrl

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.7.7

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all platforms: glibc 2.41, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.259 remainder

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/remainder.html

Gnulib module: remainder or remainder-ieee

Portability problems fixed by either Gnulib module remainder or remainder-ieee:

  • This function is missing on some platforms: MSVC 9.

Portability problems fixed by Gnulib module remainder-ieee:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.260 remainderf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/remainderf.html

Gnulib module: remainderf or remainderf-ieee

Portability problems fixed by either Gnulib module remainderf or remainderf-ieee:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.

Portability problems fixed by Gnulib module remainderf-ieee:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.261 remainderl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/remainderl.html

Gnulib module: remainderl or remainderl-ieee

Portability problems fixed by either Gnulib module remainderl or remainderl-ieee:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 9.3, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9, Android 4.4.
  • This function returns completely wrong values on some platforms: OpenBSD 5.1/SPARC.
  • This function produces results which are accurate to only 16 digits on some platforms: musl libc 1.2.2/arm64, musl libc 1.2.2/s390x, NetBSD 10.0.

Portability problems fixed by Gnulib module remainderl-ieee:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.262 remquo

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/remquo.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.263 remquof

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/remquof.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.264 remquol

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/remquol.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 9.3, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9, Android 4.4.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.265 rint

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/rint.html

Gnulib module: rint or rint-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: MSVC 9.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.266 rintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/rintf.html

Gnulib module: rintf or rintf-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.267 rintl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/rintl.html

Gnulib module: rintl or rintl-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.5.x, MSVC 9, Android 4.4.
  • This function produces wrong results for negative numbers on some platforms: NetBSD 8.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.268 rootn

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.7.8

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all platforms: glibc 2.41, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.269 rootnf

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.7.8

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all platforms: glibc 2.41, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.270 rootnl

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.7.8

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all platforms: glibc 2.41, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.271 round

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/round.html

Gnulib module: round or round-ieee

Portability problems fixed by either Gnulib module round or round-ieee:

  • This function is missing on some platforms: FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, Solaris 9, MSVC 9.
  • This function is not declared on some platforms: glibc 2.8.
  • This functions returns a wrong result for x = 1/2 - 2^-54 on some platforms: NetBSD 3.0, AIX 7.1, mingw with MSVCRT.

Portability problems fixed by Gnulib module round-ieee:

  • This function returns a positive zero for an argument between −0.5 and 0 on some platforms: AIX 7.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.272 roundeven

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Rounding-Functions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.273 roundevenf

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Rounding-Functions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.274 roundevenl

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Rounding-Functions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.275 roundf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/roundf.html

Gnulib module: roundf or roundf-ieee

Portability problems fixed by either Gnulib module roundf or roundf-ieee:

  • This function is missing on some platforms: FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.
  • This function is not declared on some platforms: glibc 2.8.
  • This functions returns a wrong result for x = 1/2 - 2^-25 on some platforms: mingw with MSVCRT.

Portability problems fixed by Gnulib module roundf-ieee:

  • This function returns a positive zero for an argument between −0.5 and 0 on some platforms: AIX 7.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.276 roundl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/roundl.html

Gnulib module: roundl or roundl-ieee

Portability problems fixed by either Gnulib module roundl or roundl-ieee:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9.
  • This function is not declared on some platforms: glibc 2.8.

Portability problems fixed by Gnulib module roundl-ieee:

  • This function returns a positive zero for an argument between −0.5 and 0 on some platforms: AIX 7.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.277 rsqrt

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.7.9

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.41, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.278 rsqrtf

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.7.9

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.41, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.279 rsqrtl

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.7.9

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.41, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.280 scalbln

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/scalbln.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.281 scalblnf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/scalblnf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.282 scalblnl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/scalblnl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.283 scalbn

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/scalbn.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.284 scalbnf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/scalbnf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.285 scalbnl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/scalbnl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.286 setpayload

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section F.10.13.2

Documentation:
https://www.gnu.org/software/libc/manual/html_node/FP-Bit-Twiddling.html.

Gnulib module: setpayload

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.287 setpayloadf

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section F.10.13.2

Documentation:
https://www.gnu.org/software/libc/manual/html_node/FP-Bit-Twiddling.html.

Gnulib module: setpayloadf

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.288 setpayloadl

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section F.10.13.2

Documentation:
https://www.gnu.org/software/libc/manual/html_node/FP-Bit-Twiddling.html.

Gnulib module: setpayloadl

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.289 setpayloadsig

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section F.10.13.3

Documentation:
https://www.gnu.org/software/libc/manual/html_node/FP-Bit-Twiddling.html.

Gnulib module: setpayloadsig

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.290 setpayloadsigf

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section F.10.13.3

Documentation:
https://www.gnu.org/software/libc/manual/html_node/FP-Bit-Twiddling.html.

Gnulib module: setpayloadsigf

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.291 setpayloadsigl

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section F.10.13.3

Documentation:
https://www.gnu.org/software/libc/manual/html_node/FP-Bit-Twiddling.html.

Gnulib module: setpayloadsigl

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.292 signbit

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/signbit.html

Gnulib module: signbit

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, OpenBSD 7.9, AIX 5.1, Solaris 11.0, MSVC 9, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.293 signgam

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/signgam.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on some platforms: macOS 10.13, Minix 3.1.8, AIX 5.1, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.294 sin

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sin.html

Gnulib module: sin

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.295 sinf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sinf.html

Gnulib module: sinf

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.296 sinh

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sinh.html

Gnulib module: sinh

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.297 sinhf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sinhf.html

Gnulib module: sinhf

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.298 sinhl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sinhl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, Android 4.4.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.
  • This function produces results which are accurate to only 16 digits on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.299 sinl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sinl.html

Gnulib module: sinl

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, Android 4.4.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.
  • This function returns a value that is larger than the argument, for some positive arguments, on some platforms: NetBSD 10.0.

Portability problems not fixed by Gnulib:

  • This function produces results which are accurate to only 16 digits on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.300 sinpi

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.13

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 13.4, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.301 sinpif

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.13

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 13.4, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.302 sinpil

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.13

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 13.4, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.303 sqrt

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sqrt.html

Gnulib module: sqrt or sqrt-ieee

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.304 sqrtf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sqrtf.html

Gnulib module: sqrtf or sqrtf-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.305 sqrtl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sqrtl.html

Gnulib module: sqrtl or sqrtl-ieee

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, Android 4.4.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.
  • This function produces very imprecise results on some platforms: OpenBSD 5.1/SPARC.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.306 tan

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tan.html

Gnulib module: tan

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.307 tanf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tanf.html

Gnulib module: tanf

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.308 tanh

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tanh.html

Gnulib module: tanh

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.309 tanhf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tanhf.html

Gnulib module: tanhf

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 9.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.310 tanhl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tanhl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, Android 4.4.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.
  • This function produces results which are accurate to only 16 digits on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.311 tanl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tanl.html

Gnulib module: tanl

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, Android 4.4.
  • This function is only defined as a macro with arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

  • This function produces results which are accurate to only 16 digits on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.312 tanpi

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.14

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 13.4, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.313 tanpif

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.14

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 13.4, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.314 tanpil

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.12.4.14

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-C23 platforms: glibc 2.40, macOS 14, FreeBSD 13.4, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.315 tgamma

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tgamma.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.316 tgammaf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tgammaf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.317 tgammal

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tgammal.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 9.3, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9, Android 4.4.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.318 totalorder

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section F.10.12.1

Documentation:

Gnulib module: totalorder

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function has a different signature on some platforms: glibc 2.30.

Portability problems not fixed by Gnulib:

  • This function treats signalling NaNs incorrectly on some platforms: glibc 2.35/sh4.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.319 totalorderf

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section F.10.12.1

Documentation:

Gnulib module: totalorderf

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function has a different signature on some platforms: glibc 2.30.

Portability problems not fixed by Gnulib:

  • This function treats signalling NaNs incorrectly on some platforms: glibc 2.35/sh4.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.320 totalorderl

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section F.10.12.1

Documentation:

Gnulib module: totalorderl

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function has a different signature on some platforms: glibc 2.30.

Portability problems not fixed by Gnulib:

  • This function treats signalling NaNs incorrectly on some platforms: glibc 2.35/sh4.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.321 totalordermag

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section F.10.12.2

Documentation:
https://www.gnu.org/software/libc/manual/html_node/FP-Comparison-Functions.html.

Gnulib module: totalordermag

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function has a different signature on some platforms: glibc 2.30.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.322 totalordermagf

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section F.10.12.2

Documentation:
https://www.gnu.org/software/libc/manual/html_node/FP-Comparison-Functions.html.

Gnulib module: totalordermagf

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function has a different signature on some platforms: glibc 2.30.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.323 totalordermagl

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section F.10.12.2

Documentation:
https://www.gnu.org/software/libc/manual/html_node/FP-Comparison-Functions.html.

Gnulib module: totalordermagl

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function has a different signature on some platforms: glibc 2.30.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.324 trunc

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/trunc.html

Gnulib module: trunc or trunc-ieee

Portability problems fixed by either Gnulib module trunc or trunc-ieee:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 3.0, OpenBSD 3.8, Solaris 9, MSVC 9.
  • This function is not declared (without -D_GNU_SOURCE) on some platforms: glibc 2.8.

Portability problems fixed by Gnulib module trunc-ieee:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.325 truncf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/truncf.html

Gnulib module: truncf or truncf-ieee

Portability problems fixed by either Gnulib module truncf or truncf-ieee:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, MSVC 9.
  • This function is not declared (without -D_GNU_SOURCE) on some platforms: glibc 2.8.

Portability problems fixed by Gnulib module truncf-ieee:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.326 truncl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/truncl.html

Gnulib module: truncl or truncl-ieee

Portability problems fixed by either Gnulib module truncl or truncl-ieee:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9.
  • This function is not declared (without -D_GNU_SOURCE) on some platforms: glibc 2.8.

Portability problems fixed by Gnulib module truncl-ieee:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.327 ufromfp

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Rounding-Functions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.328 ufromfpf

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Rounding-Functions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.329 ufromfpl

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Rounding-Functions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.330 ufromfpx

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Rounding-Functions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.331 ufromfpxf

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Rounding-Functions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.332 ufromfpxl

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Rounding-Functions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.333 y0

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/y0.html

Gnulib module: y0

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.

Next: , Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.334 y1

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/y1.html

Gnulib module: y1

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.

Previous: , Up: Functions in <math.h>   [Contents][Index]

10.24.335 yn

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/yn.html

Gnulib module: yn

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.25 Functions in <monetary.h>

Next: , Up: Functions in <monetary.h>   [Contents][Index]

10.25.1 strfmon

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strfmon.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 1.7.1, mingw, MSVC 14, Android 9.0.

Previous: , Up: Functions in <monetary.h>   [Contents][Index]

10.25.2 strfmon_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strfmon_l.html

Gnulib module: strfmon_l

Portability problems fixed by Gnulib:

  • This function ignores the locale argument on some platforms: FreeBSD 13.0, Cygwin 2.9.
  • This function uses a wrong locale for the numbers on some platforms: glibc 2.23.

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 7.1, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.26 Functions in <mqueue.h>

Next: , Up: Functions in <mqueue.h>   [Contents][Index]

10.26.1 mq_close

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mq_close.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <mqueue.h>   [Contents][Index]

10.26.2 mq_getattr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mq_getattr.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <mqueue.h>   [Contents][Index]

10.26.3 mq_notify

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mq_notify.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <mqueue.h>   [Contents][Index]

10.26.4 mq_open

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mq_open.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <mqueue.h>   [Contents][Index]

10.26.5 mq_receive

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mq_receive.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <mqueue.h>   [Contents][Index]

10.26.6 mq_send

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mq_send.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <mqueue.h>   [Contents][Index]

10.26.7 mq_setattr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mq_setattr.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <mqueue.h>   [Contents][Index]

10.26.8 mq_timedreceive

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mq_timedreceive.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <mqueue.h>   [Contents][Index]

10.26.9 mq_timedsend

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mq_timedsend.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.27 Functions in <ndbm.h>

Next: , Up: Functions in <ndbm.h>   [Contents][Index]

10.27.1 dbm_clearerr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dbm_clearerr.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, HP-UX 11.11, Cygwin 3.0.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <ndbm.h>   [Contents][Index]

10.27.2 dbm_close

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dbm_close.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Cygwin 3.0.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <ndbm.h>   [Contents][Index]

10.27.3 dbm_delete

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dbm_delete.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Cygwin 3.0.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <ndbm.h>   [Contents][Index]

10.27.4 dbm_error

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dbm_error.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, HP-UX 11.11, Cygwin 3.0.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <ndbm.h>   [Contents][Index]

10.27.5 dbm_fetch

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dbm_fetch.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Cygwin 3.0.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <ndbm.h>   [Contents][Index]

10.27.6 dbm_firstkey

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dbm_firstkey.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Cygwin 3.0.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <ndbm.h>   [Contents][Index]

10.27.7 dbm_nextkey

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dbm_nextkey.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Cygwin 3.0.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <ndbm.h>   [Contents][Index]

10.27.8 dbm_open

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dbm_open.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Cygwin 3.0.x, mingw, MSVC 14, Android 9.0.

Previous: , Up: Functions in <ndbm.h>   [Contents][Index]

10.27.9 dbm_store

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dbm_store.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Cygwin 3.0.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.28 Functions in <net/if.h>

Next: , Up: Functions in <net/if.h>   [Contents][Index]

10.28.1 if_freenameindex

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/if_freenameindex.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, HP-UX 11.23, Cygwin 1.5.x, mingw, MSVC 14, Android 6.0.
  • This is available only as a macro, rather than a function, on some platforms: OpenBSD 4.6, MirBSD 10.

Next: , Previous: , Up: Functions in <net/if.h>   [Contents][Index]

10.28.2 if_indextoname

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/if_indextoname.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.23, Cygwin 1.5.x, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <net/if.h>   [Contents][Index]

10.28.3 if_nameindex

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/if_nameindex.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.23, Cygwin 1.5.x, mingw, MSVC 14, Android 6.0.

Previous: , Up: Functions in <net/if.h>   [Contents][Index]

10.28.4 if_nametoindex

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/if_nametoindex.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.23, Cygwin 1.5.x, mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.29 Functions in <netdb.h>

Next: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.1 endhostent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/endhostent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.2 endnetent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/endnetent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Cygwin 2.9, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.3 endprotoent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/endprotoent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.4 endservent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/endservent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.5 freeaddrinfo

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/freeaddrinfo.html

Gnulib module: getaddrinfo

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11.11, Cygwin 1.5.x, mingw, MSVC 14.
  • On Windows, this function is declared in <ws2tcpip.h> rather than in <netdb.h>.
  • On Windows, in 32-bit mode, this function is defined with a calling convention that is different from cdecl.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.6 gai_strerror

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/gai_strerror.html

Gnulib module: getaddrinfo

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11.11, Cygwin 1.5.x.
  • This function is only available in <ws2tcpip.h> on some platforms: mingw, MSVC 14.
  • This function’s return type is char * instead of const char * on some platforms: AIX 7.1, HP-UX 11, Solaris 9, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.7 getaddrinfo

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getaddrinfo.html

Gnulib module: getaddrinfo

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11.11, Cygwin 1.5.x, mingw, MSVC 14.
  • On native Windows, this function is declared in <ws2tcpip.h> rather than in <netdb.h>.
  • On native Windows, this function does not support the AI_NUMERICSERV hints flag.
  • On native Windows, in 32-bit mode, this function is defined with a calling convention that is different from cdecl.
  • On Solaris 10, this function does not support the AI_NUMERICHOST hints flag.

Portability problems not fixed by Gnulib:

  • Unlike glibc’s implementation, gnulib’s replacement does not support internationalized domain names (IDN) encoding.

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.8 gethostent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/gethostent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.9 getnameinfo

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getnameinfo.html

Gnulib module: getaddrinfo

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11.11, Cygwin 1.5.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.10 getnetbyaddr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getnetbyaddr.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.11 getnetbyname

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getnetbyname.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.12 getnetent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getnetent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Cygwin 2.9, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.13 getprotobyname

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getprotobyname.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <netdb.h> on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.14 getprotobynumber

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getprotobynumber.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <netdb.h> on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.15 getprotoent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getprotoent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.16 getservbyname

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getservbyname.html

Gnulib module: servent

Portability problems fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <netdb.h> on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • On Windows, in 32-bit mode, this function is defined with a calling convention that is different from cdecl.

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.17 getservbyport

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getservbyport.html

Gnulib module: servent

Portability problems fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <netdb.h> on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • On Windows, in 32-bit mode, this function is defined with a calling convention that is different from cdecl.

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.18 getservent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getservent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.19 sethostent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sethostent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.20 setnetent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setnetent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Cygwin 2.9, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.21 setprotoent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setprotoent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 8.1.

Previous: , Up: Functions in <netdb.h>   [Contents][Index]

10.29.22 setservent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setservent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.30 Functions in <netinet/in.h>

Next: , Up: Functions in <netinet/in.h>   [Contents][Index]

10.30.1 in6addr_any

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/in6addr_any.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Host-Address-Data-Type.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This constant is missing on some platforms: Minix 3.1.8, HP-UX 11.00, Cygwin 1.5.x, mingw, MSVC 14, Android 6.0.

Previous: , Up: Functions in <netinet/in.h>   [Contents][Index]

10.30.2 in6addr_loopback

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/in6addr_loopback.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Host-Address-Data-Type.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This constant is missing on some platforms: Minix 3.1.8, HP-UX 11.00, Cygwin 1.5.x, mingw, MSVC 14, Android 6.0.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.31 Functions in <nl_types.h>

Next: , Up: Functions in <nl_types.h>   [Contents][Index]

10.31.1 catclose

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/catclose.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9.x, mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: Functions in <nl_types.h>   [Contents][Index]

10.31.2 catgets

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/catgets.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9.x, mingw, MSVC 14, Android 7.1.

Previous: , Up: Functions in <nl_types.h>   [Contents][Index]

10.31.3 catopen

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/catopen.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9.x, mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.32 Functions in <poll.h>

Next: , Up: Functions in <poll.h>   [Contents][Index]

10.32.1 poll

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/poll.html

Gnulib module: poll

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, HP NonStop.
  • This function doesn’t work on special files like /dev/null and ttys like /dev/tty on some platforms: macOS 14, AIX 5.3.

Portability problems not fixed by Gnulib:

  • Under Windows, when passing a pipe, Gnulib’s poll replacement might return 0 even before the timeout has passed. Programs using it with pipes can thus busy wait.
  • On some platforms, file descriptors other than sockets do not support POLLHUP; they will return a "readable" or "writable" status instead: AIX 7.2, Cygwin 3.4.6, HP NonStop, mingw, MSVC.

Previous: , Up: Functions in <poll.h>   [Contents][Index]

10.32.2 ppoll

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ppoll.html

Documentation:
man ppoll

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 6.4, NetBSD 9.3, OpenBSD 3.8, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 10, Cygwin 1.7.x, mingw, MSVC 14, Android 4.3.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.33 Functions in <pthread.h>

Next: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.1 pthread_atfork

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_atfork.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, mingw, MSVC 14, Android 3.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.2 pthread_attr_destroy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_attr_destroy.html

Gnulib module: pthread-thread

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.3 pthread_attr_getdetachstate

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_attr_getdetachstate.html

Gnulib module: pthread-thread

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.4 pthread_attr_getguardsize

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_attr_getguardsize.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, Cygwin 1.7.9, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.5 pthread_attr_getinheritsched

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_attr_getinheritsched.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.6 pthread_attr_getschedparam

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_attr_getschedparam.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.7 pthread_attr_getschedpolicy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_attr_getschedpolicy.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.8 pthread_attr_getscope

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_attr_getscope.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.9 pthread_attr_getstack

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_attr_getstack.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11.11, Solaris 9, Cygwin 1.7.9, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.10 pthread_attr_getstacksize

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_attr_getstacksize.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.11 pthread_attr_init

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_attr_init.html

Gnulib module: pthread-thread

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.
  • This function is only defined as an inline function on some platforms: HP-UX 11.11.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.12 pthread_attr_setdetachstate

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_attr_setdetachstate.html

Gnulib module: pthread-thread

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.13 pthread_attr_setguardsize

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_attr_setguardsize.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, Cygwin 1.7.9, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.14 pthread_attr_setinheritsched

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_attr_setinheritsched.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.15 pthread_attr_setschedparam

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_attr_setschedparam.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.16 pthread_attr_setschedpolicy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_attr_setschedpolicy.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.17 pthread_attr_setscope

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_attr_setscope.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.18 pthread_attr_setstack

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_attr_setstack.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11.11, Solaris 9, Cygwin 1.7.9, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.19 pthread_attr_setstacksize

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_attr_setstacksize.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.20 pthread_barrier_destroy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_barrier_destroy.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 6.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.21 pthread_barrier_init

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_barrier_init.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 6.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.22 pthread_barrier_wait

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_barrier_wait.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 6.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.23 pthread_barrierattr_destroy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_barrierattr_destroy.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 6.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.24 pthread_barrierattr_getpshared

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_barrierattr_getpshared.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.2, macOS 14, FreeBSD 5.2.1, NetBSD 10.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 6.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.25 pthread_barrierattr_init

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_barrierattr_init.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 6.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.26 pthread_barrierattr_setpshared

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_barrierattr_setpshared.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 5.2.1, NetBSD 10.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 6.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.27 pthread_cancel

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_cancel.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.28 pthread_cleanup_pop

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_cleanup_pop.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, NetBSD 10.0, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.29 pthread_cleanup_push

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_cleanup_push.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, NetBSD 10.0, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.30 pthread_cond_broadcast

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_cond_broadcast.html

Gnulib module: pthread-cond

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.31 pthread_cond_clockwait

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_cond_clockwait.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 3.2.x, mingw, MSVC 14, Android API level 29.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.32 pthread_cond_destroy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_cond_destroy.html

Gnulib module: pthread-cond

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.33 pthread_cond_init

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_cond_init.html

Gnulib module: pthread-cond

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.34 pthread_cond_signal

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_cond_signal.html

Gnulib module: pthread-cond

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.35 pthread_cond_timedwait

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_cond_timedwait.html

Gnulib module: pthread-cond

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

  • This function sometimes waits indefinitely instead of up to the specified time point, on some platforms (glibc/Linux, musl libc) in some hypervisors: VirtualBox 6.1.50_Ubuntu with paravirtualization set to "Default" or "KVM".

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.36 pthread_cond_wait

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_cond_wait.html

Gnulib module: pthread-cond

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.37 pthread_condattr_destroy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_condattr_destroy.html

Gnulib module: pthread-cond

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.38 pthread_condattr_getclock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_condattr_getclock.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.2, macOS 14, FreeBSD 5.2.1, NetBSD 7.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.9, mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.39 pthread_condattr_getpshared

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_condattr_getpshared.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.40 pthread_condattr_init

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_condattr_init.html

Gnulib module: pthread-cond

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.41 pthread_condattr_setclock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_condattr_setclock.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.2, macOS 14, FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.9, mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.42 pthread_condattr_setpshared

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_condattr_setpshared.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.43 pthread_create

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_create.html

Gnulib module: pthread-thread

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.
  • This function is only defined as an inline function on some platforms: HP-UX 11.11.

Portability problems not fixed by Gnulib:

  • On Linux/glibc platforms before the advent of NPTL in 2003, signals could only be sent to one particular thread. In POSIX, signals are sent to the entire process and executed by any thread of the process that happens to have the particular signal currently unblocked.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.44 pthread_detach

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_detach.html

Gnulib module: pthread-thread

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.45 pthread_equal

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_equal.html

Gnulib module: pthread-thread

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.46 pthread_exit

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_exit.html

Gnulib module: pthread-thread

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.47 pthread_getcpuclockid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_getcpuclockid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 7.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.9, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.48 pthread_getschedparam

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_getschedparam.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.49 pthread_getspecific

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_getspecific.html

Gnulib module: pthread-tss

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.50 pthread_join

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_join.html

Gnulib module: pthread-thread

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.51 pthread_key_create

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_key_create.html

Gnulib module: pthread-tss

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.52 pthread_key_delete

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_key_delete.html

Gnulib module: pthread-tss

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.53 pthread_mutex_clocklock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutex_clocklock.html

Documentation: —

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 3.2.x, mingw, MSVC 14, Android API level 29.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.54 pthread_mutex_consistent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutex_consistent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.11, macOS 14, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.55 pthread_mutex_destroy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutex_destroy.html

Gnulib module: pthread-mutex

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.56 pthread_mutex_getprioceiling

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutex_getprioceiling.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, NetBSD 7.1, Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.57 pthread_mutex_init

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutex_init.html

Gnulib module: pthread-mutex

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 4.3. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.58 pthread_mutex_lock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutex_lock.html

Gnulib module: pthread-mutex

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

  • This function does not behave as required by POSIX for mutexes of type NORMAL and ERRORCHECK, by allowing RECURSIVE locking, in programs linked without -lpthread on some platforms: FreeBSD 14.0, NetBSD 10.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.59 pthread_mutex_setprioceiling

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutex_setprioceiling.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, NetBSD 7.1, Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.60 pthread_mutex_timedlock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutex_timedlock.html

Gnulib module: pthread_mutex_timedlock

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 5.2.1, NetBSD 7.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.61 pthread_mutex_trylock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutex_trylock.html

Gnulib module: pthread-mutex

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

  • This function does not behave as required by POSIX for mutexes of type NORMAL and ERRORCHECK, by allowing RECURSIVE locking, in programs linked without -lpthread on some platforms: FreeBSD 14.0, NetBSD 10.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.62 pthread_mutex_unlock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutex_unlock.html

Gnulib module: pthread-mutex

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.63 pthread_mutexattr_destroy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutexattr_destroy.html

Gnulib module: pthread-mutex

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.64 pthread_mutexattr_getprioceiling

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutexattr_getprioceiling.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, NetBSD 7.1, Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.65 pthread_mutexattr_getprotocol

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutexattr_getprotocol.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, NetBSD 7.1, Minix 3.1.8, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.66 pthread_mutexattr_getpshared

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutexattr_getpshared.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.67 pthread_mutexattr_getrobust

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutexattr_getrobust.html

Gnulib module: pthread-mutex

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.11, macOS 14, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 2.9, mingw, MSVC 14, Android 9.0. But the provided replacement is just a dummy.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.68 pthread_mutexattr_gettype

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutexattr_gettype.html

Gnulib module: pthread-mutex

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.69 pthread_mutexattr_init

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutexattr_init.html

Gnulib module: pthread-mutex

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.70 pthread_mutexattr_setprioceiling

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutexattr_setprioceiling.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, NetBSD 7.1, Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.71 pthread_mutexattr_setprotocol

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutexattr_setprotocol.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, NetBSD 7.1, Minix 3.1.8, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.72 pthread_mutexattr_setpshared

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutexattr_setpshared.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.73 pthread_mutexattr_setrobust

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutexattr_setrobust.html

Gnulib module: pthread-mutex

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.11, macOS 14, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 2.9, mingw, MSVC 14, Android 9.0. But the provided replacement is just a dummy.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.74 pthread_mutexattr_settype

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_mutexattr_settype.html

Gnulib module: pthread-mutex

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.75 pthread_once

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_once.html

Gnulib module: pthread-once

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.
  • This function makes applications hang forever on some platforms: Cygwin 3.5.3.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.76 pthread_rwlock_clockrdlock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_rwlock_clockrdlock.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 3.2.x, mingw, MSVC 14, Android API level 29.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.77 pthread_rwlock_clockwrlock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_rwlock_clockwrlock.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 3.2.x, mingw, MSVC 14, Android API level 29.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.78 pthread_rwlock_destroy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_rwlock_destroy.html

Gnulib module: pthread-rwlock

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 4.3. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.79 pthread_rwlock_init

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_rwlock_init.html

Gnulib module: pthread-rwlock

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 4.3. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.80 pthread_rwlock_rdlock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_rwlock_rdlock.html

Gnulib module: pthread-rwlock

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 4.3. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.
  • This function prefers readers to writers (meaning, when this function is called on an rwlock that is already taken by one or more readers, and another writer is already waiting to take it, this function may return successfully immediately) – a behaviour that may lead to writer starvation – on some platforms: glibc 2.42.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.81 pthread_rwlock_timedrdlock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_rwlock_timedrdlock.html

Gnulib module: pthread-rwlock

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 4.3. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.
  • This function prefers readers to writers (meaning, when this function is called on an rwlock that is already taken by one or more readers, and another writer is already waiting to take it, this function may return successfully immediately) – a behaviour that may lead to writer starvation – on some platforms: glibc 2.42.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.82 pthread_rwlock_timedwrlock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_rwlock_timedwrlock.html

Gnulib module: pthread-rwlock

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 4.3. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.83 pthread_rwlock_tryrdlock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_rwlock_tryrdlock.html

Gnulib module: pthread-rwlock

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 4.3. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.
  • This function prefers readers to writers (meaning, when this function is called on an rwlock that is already taken by one or more readers, and another writer is already waiting to take it, this function may return successfully immediately) – a behaviour that may lead to writer starvation – on some platforms: glibc 2.42.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.84 pthread_rwlock_trywrlock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_rwlock_trywrlock.html

Gnulib module: pthread-rwlock

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 4.3. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

  • This function returns EDEADLK instead of EBUSY when the current thread already owns the lock for writing on some platforms: macOS 12.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.85 pthread_rwlock_unlock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_rwlock_unlock.html

Gnulib module: pthread-rwlock

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 4.3. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.86 pthread_rwlock_wrlock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_rwlock_wrlock.html

Gnulib module: pthread-rwlock

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 4.3. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.87 pthread_rwlockattr_destroy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_rwlockattr_destroy.html

Gnulib module: pthread-rwlock

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.88 pthread_rwlockattr_getpshared

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_rwlockattr_getpshared.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 10.0, Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.89 pthread_rwlockattr_init

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_rwlockattr_init.html

Gnulib module: pthread-rwlock

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.90 pthread_rwlockattr_setpshared

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_rwlockattr_setpshared.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 10.0, Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.91 pthread_self

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_self.html

Gnulib module: pthread-thread

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.92 pthread_setcancelstate

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_setcancelstate.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.93 pthread_setcanceltype

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_setcanceltype.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.94 pthread_setschedparam

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_setschedparam.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.95 pthread_setschedprio

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_setschedprio.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.3, macOS 14, FreeBSD 14.0, NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.9, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.96 pthread_setspecific

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_setspecific.html

Gnulib module: pthread-tss

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.97 pthread_spin_destroy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_spin_destroy.html

Gnulib module: pthread-spin

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.9, mingw, MSVC 14, Android 6.0. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.98 pthread_spin_init

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_spin_init.html

Gnulib module: pthread-spin

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.9, mingw, MSVC 14, Android 6.0. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.99 pthread_spin_lock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_spin_lock.html

Gnulib module: pthread-spin

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.9, mingw, MSVC 14, Android 6.0. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.100 pthread_spin_trylock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_spin_trylock.html

Gnulib module: pthread-spin

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.9, mingw, MSVC 14, Android 6.0. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.101 pthread_spin_unlock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_spin_unlock.html

Gnulib module: pthread-spin

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 5.2.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.9, mingw, MSVC 14, Android 6.0. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Previous: , Up: Functions in <pthread.h>   [Contents][Index]

10.33.102 pthread_testcancel

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_testcancel.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.34 Functions in <pwd.h>

Next: , Up: Functions in <pwd.h>   [Contents][Index]

10.34.1 endpwent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/endpwent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pwd.h>   [Contents][Index]

10.34.2 getpwent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getpwent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: Functions in <pwd.h>   [Contents][Index]

10.34.3 getpwnam

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getpwnam.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pwd.h>   [Contents][Index]

10.34.4 getpwnam_r

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getpwnam_r.html

Gnulib module: extensions

Portability problems fixed by Gnulib:

  • This function has an incompatible declaration on some platforms: Solaris 11.3 (when _POSIX_PTHREAD_SEMANTICS is not defined).

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, mingw, MSVC 14, Android 3.0.

Next: , Previous: , Up: Functions in <pwd.h>   [Contents][Index]

10.34.5 getpwuid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getpwuid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is unsafe to call between fork and exec if the parent process is multi-threaded. Instead, use getpwuid_r prior to forking.
  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <pwd.h>   [Contents][Index]

10.34.6 getpwuid_r

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getpwuid_r.html

Gnulib module: extensions

Portability problems fixed by Gnulib:

  • This function has an incompatible declaration on some platforms: Solaris 11.3 (when _POSIX_PTHREAD_SEMANTICS is not defined).

Portability problems not fixed by Gnulib:

  • This function is unsafe to call between fork and exec if the parent process is multi-threaded. Use it prior to forking.
  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, mingw, MSVC 14, Android 3.0.

Previous: , Up: Functions in <pwd.h>   [Contents][Index]

10.34.7 setpwent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setpwent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.35 Functions in <regex.h>

Next: , Up: Functions in <regex.h>   [Contents][Index]

10.35.1 regcomp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/regcomp.html

Gnulib module: regex

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • Many regular expression implementations have bugs.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <regex.h>   [Contents][Index]

10.35.2 regerror

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/regerror.html

Gnulib module: regex

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <regex.h>   [Contents][Index]

10.35.3 regexec

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/regexec.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-regexec-2.html

Gnulib module: regex

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • Many regular expression implementations have bugs.

Portability problems not fixed by Gnulib:

Previous: , Up: Functions in <regex.h>   [Contents][Index]

10.35.4 regfree

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/regfree.html

Gnulib module: regex

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.36 Functions in <sched.h>

Next: , Up: Functions in <sched.h>   [Contents][Index]

10.36.1 sched_get_priority_max

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sched_get_priority_max.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <sched.h>   [Contents][Index]

10.36.2 sched_get_priority_min

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sched_get_priority_min.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <sched.h>   [Contents][Index]

10.36.3 sched_getparam

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sched_getparam.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14.
  • This function always fails with error ENOSYS on some platforms: musl libc.

Next: , Previous: , Up: Functions in <sched.h>   [Contents][Index]

10.36.4 sched_getscheduler

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sched_getscheduler.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14.
  • This function always fails with error ENOSYS on some platforms: musl libc.

Next: , Previous: , Up: Functions in <sched.h>   [Contents][Index]

10.36.5 sched_rr_get_interval

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sched_rr_get_interval.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <sched.h>   [Contents][Index]

10.36.6 sched_setparam

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sched_setparam.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14.
  • This function always fails with error ENOSYS on some platforms: musl libc.

Next: , Previous: , Up: Functions in <sched.h>   [Contents][Index]

10.36.7 sched_setscheduler

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sched_setscheduler.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-sched-setscheduler.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14.
  • This function always fails with error ENOSYS on some platforms: musl libc.

Previous: , Up: Functions in <sched.h>   [Contents][Index]

10.36.8 sched_yield

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sched_yield.html

Gnulib module: sched_yield

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. But the provided replacement is just a dummy on some of these platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.37 Functions in <search.h>

Next: , Up: Functions in <search.h>   [Contents][Index]

10.37.1 hcreate

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/hcreate.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Functions in <search.h>   [Contents][Index]

10.37.2 hdestroy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/hdestroy.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Functions in <search.h>   [Contents][Index]

10.37.3 hsearch

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/hsearch.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Functions in <search.h>   [Contents][Index]

10.37.4 insque

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/insque.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.5.x, mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Functions in <search.h>   [Contents][Index]

10.37.5 lfind

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lfind.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Android 4.4.

Next: , Previous: , Up: Functions in <search.h>   [Contents][Index]

10.37.6 lsearch

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lsearch.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Android 4.4.

Next: , Previous: , Up: Functions in <search.h>   [Contents][Index]

10.37.7 remque

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/remque.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.5.x, mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Functions in <search.h>   [Contents][Index]

10.37.8 tdelete

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tdelete.html

Gnulib module: tsearch

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 4.0.4.
  • tdelete returns NULL when removing the last element of a tree on some platforms: OpenBSD 4.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <search.h>   [Contents][Index]

10.37.9 tfind

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tfind.html

Gnulib module: tsearch

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 4.0.4.

Portability problems not fixed by Gnulib:

  • This function uses void ** instead of void *const * for the second parameter on some platforms: Cygwin.

Next: , Previous: , Up: Functions in <search.h>   [Contents][Index]

10.37.10 tsearch

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tsearch.html

Gnulib module: tsearch

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 4.0.4.

Portability problems not fixed by Gnulib:

Previous: , Up: Functions in <search.h>   [Contents][Index]

10.37.11 twalk

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/twalk.html

Gnulib module: tsearch

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.38 Functions in <semaphore.h>

Next: , Up: Functions in <semaphore.h>   [Contents][Index]

10.38.1 sem_clockwait

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sem_clockwait.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 3.2.x, mingw, MSVC 14, Android API level 29.

Next: , Previous: , Up: Functions in <semaphore.h>   [Contents][Index]

10.38.2 sem_close

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sem_close.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <semaphore.h>   [Contents][Index]

10.38.3 sem_destroy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sem_destroy.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • This function is not implemented on some platforms: Mac OS X 10.11.

Next: , Previous: , Up: Functions in <semaphore.h>   [Contents][Index]

10.38.4 sem_getvalue

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sem_getvalue.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • This function is not implemented on some platforms: Mac OS X 10.11.

Next: , Previous: , Up: Functions in <semaphore.h>   [Contents][Index]

10.38.5 sem_init

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sem_init.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • This function is not implemented on some platforms: Mac OS X 10.11.

Next: , Previous: , Up: Functions in <semaphore.h>   [Contents][Index]

10.38.6 sem_open

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sem_open.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <semaphore.h>   [Contents][Index]

10.38.7 sem_post

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sem_post.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <semaphore.h>   [Contents][Index]

10.38.8 sem_timedwait

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sem_timedwait.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <semaphore.h>   [Contents][Index]

10.38.9 sem_trywait

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sem_trywait.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Previous: , Up: Functions in <semaphore.h>   [Contents][Index]

10.38.11 sem_wait

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sem_wait.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.39 Functions in <setjmp.h>

Next: , Up: Functions in <setjmp.h>   [Contents][Index]

10.39.1 longjmp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/longjmp.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • The effects of this call are system and compiler optimization dependent, since it restores the contents of register-allocated variables but not the contents of stack-allocated variables.
  • When longjumping out of a signal handler that was being executed on an alternate stack (installed through sigaltstack), on Hurd, FreeBSD, NetBSD, OpenBSD, you need to clear the SS_ONSTACK flag in the stack_t structure managed by the kernel.
  • This function may crash when the invoker code was compiled with option _FORTIFY_SOURCE >= 2 on Hurd.

Next: , Previous: , Up: Functions in <setjmp.h>   [Contents][Index]

10.39.2 setjmp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setjmp.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • POSIX does not specify whether setjmp saves the signal mask in the jmp_buf. It does on BSD platforms, and on glibc platforms when _BSD_SOURCE (and/or _DEFAULT_SOURCE on glibc >= 2.19) is defined; in this case setjmp behaves like sigsetjmp(.,1), and functions _setjmp and _longjmp are available that don’t save or restore the signal mask. On System V platforms (excluding HP-UX), and on glibc platforms by default, setjmp doesn’t save the signal mask.

Next: , Previous: , Up: Functions in <setjmp.h>   [Contents][Index]

10.39.3 siglongjmp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/siglongjmp.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • This is only provided as a macro on some platforms: Cygwin.

Previous: , Up: Functions in <setjmp.h>   [Contents][Index]

10.39.4 sigsetjmp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sigsetjmp.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.40 Functions in <signal.h>

Next: , Up: Functions in <signal.h>   [Contents][Index]

10.40.1 kill

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/kill.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-kill-3.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.2 killpg

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/killpg.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.3 psiginfo

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/psiginfo.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.9, macOS 14, FreeBSD 14.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.7.9, mingw, MSVC 14, Android 4.1.

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.4 psignal

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/psignal.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11, Cygwin 1.7.9, mingw, MSVC 14, Android API level 16.
  • This function is declared in <siginfo.h>, not <signal.h>, on some platforms: Solaris 11.3.
  • The first parameter is of type unsigned int, not int, on some platforms: macOS 13, FreeBSD 10.4, NetBSD 5.1, OpenBSD 7.9.

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.5 pthread_kill

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_kill.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.6 pthread_sigmask

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pthread_sigmask.html

Gnulib module: pthread_sigmask

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • This function is declared in <pthread.h> instead of <signal.h> on some platforms: FreeBSD 6.4, OpenBSD 3.8.
  • This function requires compiling with -pthread and/or linking with -lpthread on some platforms: glibc 2.31, NetBSD, OpenBSD 5.8.
  • This function does nothing and always returns 0 in programs that are not linked with -lpthread on some platforms: FreeBSD 14.0, MidnightBSD 1.1, HP-UX 11.31, Solaris 9.
  • When it fails, this function returns −1 instead of the error number on some platforms: Cygwin 1.7.5, NetBSD 9.3 when libpthread is not in use.

Portability problems not fixed by Gnulib:

  • On platforms that do not natively support this function, it has unspecified behavior in a multi-threaded process. For example, the Gnulib replacement on native MS-Windows can affect the signal masks of other threads, which can lead to race conditions.
  • The Gnulib replacement on native MS-Windows is not async-signal-safe (see POSIX section “Signal Actions”).

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.7 raise

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/raise.html

Gnulib module: raise

Portability problems fixed by Gnulib:

  • This function is missing on some old platforms.
  • This function crashes when invoked with invalid arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.8 sig2str

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sig2str.html

Gnulib module: sig2str

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.42, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Cygwin 3.2.x, mingw, MSVC 14, Android API level 35.

Portability problems not fixed by Gnulib:

  • This function does not map the argument 0 to "EXIT" on some platforms: FreeBSD 15.0.

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.9 sigaction

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sigaction.html

Gnulib module: sigaction

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • POSIX recommends that when specifying SA_RESETHAND, SA_NODEFER must also be specified.
  • Support for SA_ONSTACK is missing on some platforms: mingw, MSVC 14, cygwin.
  • Support for SA_SIGINFO is missing on some platforms: mingw, MSVC 14.
  • Support for SIGCHLD, and thus for SA_NOCLDSTOP and SA_NOCLDWAIT, is missing on some platforms: mingw, MSVC 14.
  • Support for SA_RESETHAND is missing on some platforms: NonStop.
  • Support for SA_RESTART is missing on some platforms: mingw, MSVC 14, NonStop.
  • The symbolic value SIG_IGN for the SIGCHLD signal is equivalent to a signal handler 
    void handle_child (int sigchld)
{
  while (waitpid (-1, NULL, WNOHANG) > 0)
    ;
}

    except that SIG_IGN for SIGCHLD has the effect that the children execution times are not accounted in the times function. On some platforms (BSD? SystemV? Linux?), you need to use the sigaction flag SA_NOCLDWAIT in order to obtain this behavior.

  • The Gnulib replacement on native MS-Windows can affect the signal masks of other threads, either when sigaction is called or when a signal handler is called, and this can lead to race conditions.
  • The Gnulib replacement on native MS-Windows is not async-signal-safe (see POSIX section “Signal Actions”).

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.10 sigaddset

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sigaddset.html

Gnulib module: sigprocmask

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.11 sigaltstack

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sigaltstack.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.x, mingw, MSVC 14.
  • sigaltstack doesn’t work on HP-UX 11/IA-64 and OpenBSD 3.6/Sparc64.

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.12 sigdelset

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sigdelset.html

Gnulib module: sigprocmask

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.13 sigemptyset

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sigemptyset.html

Gnulib module: sigprocmask

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.14 sigfillset

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sigfillset.html

Gnulib module: sigprocmask

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.15 sigismember

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sigismember.html

Gnulib module: sigprocmask

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.16 signal

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/signal.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function crashes when invoked with invalid arguments on some platforms: MSVC 14.
  • On System V platforms, when the signal is triggered, the kernel uninstalls the handler (i.e. resets the signal’s action to SIG_DFL) before invoking the handler. This opens the door to race conditions: undesired things happen if the signal is triggered twice and the signal handler was not quick enough reinstalling itself as a handler. On BSD platforms and glibc platforms, on the other hand, when the signal is triggered, the kernel blocks the signal before invoking the handler. This is saner, but POSIX still allows either behavior. To avoid this problem, use sigaction instead of signal.

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.17 sigpending

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sigpending.html

Gnulib module: sigprocmask

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.18 sigprocmask

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sigprocmask.html

Gnulib module: sigprocmask

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • In case of failure, the return value is wrong on some platforms: NetBSD 10.0 when libpthread is in use.
  • POSIX says that in multi-threaded processes sigprocmask has unspecified behavior so pthread_sigmask should be used instead. On most platforms, sigprocmask is essentially equivalent to pthread_sigmask, with only a difference regarding the error return convention. However, on macOS and on the Gnulib replacement on native MS-Windows, sigprocmask can affect the signal masks of other threads, which can lead to race conditions.
  • The Gnulib replacement on native MS-Windows is not async-signal-safe (see POSIX section “Signal Actions”).

Note: In single-threaded programs it’s simpler to use sigprocmask, since it does not require compiling with -pthread and/or linking with -lpthread on some platforms: AIX.

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.19 sigqueue

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sigqueue.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14, Android 5.1.

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.20 sigsuspend

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sigsuspend.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.21 sigtimedwait

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sigtimedwait.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9.x, mingw, MSVC 14, Android 5.1.
  • Linux implements the meaning of NULL timeout by doing what sigwaitinfo does; other platforms may not do the same.

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.22 sigwait

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sigwait.html

Gnulib module: extensions

Portability problems fixed by Gnulib:

  • This function has an incompatible declaration on some platforms: Solaris 11.4 (when _POSIX_PTHREAD_SEMANTICS is not defined).

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • On Linux/glibc platforms before the advent of NPTL, signals could only be sent to one particular thread. In POSIX, signals are sent to the entire process and executed by any thread of the process that happens to have the particular signal currently unblocked.

Next: , Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.23 sigwaitinfo

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sigwaitinfo.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14, Android 5.1.

Previous: , Up: Functions in <signal.h>   [Contents][Index]

10.40.24 str2sig

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/str2sig.html

Gnulib module: sig2str

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.42, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Cygwin 3.2.x, mingw, MSVC 14, Android API level 35.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.41 Functions in <spawn.h>

Next: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.1 posix_spawn

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawn.html

Gnulib module: posix_spawn

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.3, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.
  • When this function fails, it causes the stdio buffer contents to be output twice on some platforms: AIX 6.1.
  • When the program to be invoked is an executable script without a ‘#!’ marker in the first line, this function executes the script as if it were a shell script, on some platforms: GNU/Hurd.

Portability problems not fixed by Gnulib:

  • This function does not work on some platforms: AIX 6.1 (under particular circumstances).

The Gnulib modules posix_spawn_file_actions_addchdir and posix_spawn_file_actions_addfchdir provide additional actions, that consist in changing the current directory of the child process before starting the specified program.

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.2 posix_spawn_file_actions_addchdir

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawn_file_actions_addchdir.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.42, macOS 14, FreeBSD 14.0, NetBSD 9.3, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.3 posix_spawn_file_actions_addclose

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawn_file_actions_addclose.html

Gnulib module: posix_spawn_file_actions_addclose

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.
  • This function does not reject a negative file descriptor on some platforms: musl libc.

Portability problems not fixed by Gnulib:

  • This function does not reject an out-of-range file descriptor on some platforms: musl libc, NetBSD, Cygwin.

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.4 posix_spawn_file_actions_adddup2

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawn_file_actions_adddup2.html

Gnulib module: posix_spawn_file_actions_adddup2

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.
  • This function does not reject a too large file descriptor on some platforms: musl libc, Solaris 11.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.5 posix_spawn_file_actions_addfchdir

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawn_file_actions_addfchdir.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.42, macOS 14, FreeBSD 14.0, NetBSD 9.3, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.6 posix_spawn_file_actions_addopen

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawn_file_actions_addopen.html

Gnulib module: posix_spawn_file_actions_addopen

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.
  • This function does not reject a too large file descriptor on some platforms: musl libc, Solaris 11.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.7 posix_spawn_file_actions_destroy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawn_file_actions_destroy.html

Gnulib module: posix_spawn_file_actions_destroy

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.8 posix_spawn_file_actions_init

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawn_file_actions_init.html

Gnulib module: posix_spawn_file_actions_init

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.9 posix_spawnattr_destroy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawnattr_destroy.html

Gnulib module: posix_spawnattr_destroy

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.10 posix_spawnattr_getflags

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawnattr_getflags.html

Gnulib module: posix_spawnattr_getflags

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.11 posix_spawnattr_getpgroup

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawnattr_getpgroup.html

Gnulib module: posix_spawnattr_getpgroup

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.12 posix_spawnattr_getschedparam

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawnattr_getschedparam.html

Gnulib module: posix_spawnattr_getschedparam

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Portability problems not fixed by Gnulib:

  • This function always fails with error ENOSYS on some platforms: musl libc.

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.13 posix_spawnattr_getschedpolicy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawnattr_getschedpolicy.html

Gnulib module: posix_spawnattr_getschedpolicy

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Portability problems not fixed by Gnulib:

  • This function always fails with error ENOSYS on some platforms: musl libc.

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.14 posix_spawnattr_getsigdefault

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawnattr_getsigdefault.html

Gnulib module: posix_spawnattr_getsigdefault

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.15 posix_spawnattr_getsigmask

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawnattr_getsigmask.html

Gnulib module: posix_spawnattr_getsigmask

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.16 posix_spawnattr_init

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawnattr_init.html

Gnulib module: posix_spawnattr_init

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.17 posix_spawnattr_setflags

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawnattr_setflags.html

Gnulib module: posix_spawnattr_setflags

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.18 posix_spawnattr_setpgroup

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawnattr_setpgroup.html

Gnulib module: posix_spawnattr_setpgroup

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.19 posix_spawnattr_setschedparam

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawnattr_setschedparam.html

Gnulib module: posix_spawnattr_setschedparam

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Portability problems not fixed by Gnulib:

  • This function always fails with error ENOSYS on some platforms: musl libc.

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.20 posix_spawnattr_setschedpolicy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawnattr_setschedpolicy.html

Gnulib module: posix_spawnattr_setschedpolicy

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Portability problems not fixed by Gnulib:

  • This function always fails with error ENOSYS on some platforms: musl libc.

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.21 posix_spawnattr_setsigdefault

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawnattr_setsigdefault.html

Gnulib module: posix_spawnattr_setsigdefault

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.22 posix_spawnattr_setsigmask

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawnattr_setsigmask.html

Gnulib module: posix_spawnattr_setsigmask

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Portability problems not fixed by Gnulib:

Previous: , Up: Functions in <spawn.h>   [Contents][Index]

10.41.23 posix_spawnp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_spawnp.html

Gnulib module: posix_spawnp

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.3, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.
  • When this function fails, it causes the stdio buffer contents to be output twice on some platforms: AIX 6.1.
  • When the program to be invoked is an executable script without a ‘#!’ marker in the first line, this function executes the script as if it were a shell script, on some platforms: glibc 2.14/Linux, glibc 2.32/Hurd, macOS 14, FreeBSD 14.0, OpenBSD 7.2, AIX 7.2, Solaris 11.4, Cygwin 3.4.6.

Portability problems not fixed by Gnulib:

  • This function does not work on some platforms: AIX 6.1 (under particular circumstances).

The Gnulib modules posix_spawn_file_actions_addchdir and posix_spawn_file_actions_addfchdir provide additional actions, that consist in changing the current directory of the child process before starting the specified program.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.42 Functions in <stdarg.h>

Next: , Up: Functions in <stdarg.h>   [Contents][Index]

10.42.1 va_arg

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/va_arg.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • The second argument of va_arg must be a type that is invariant under the “default argument promotions” (ISO C 99 6.5.2.2 paragraph 6). This means that the following are not valid here:
    ‘float’

    Use ‘double’ instead.

    ‘bool’

    Use ‘int’ instead.

    Integer types smaller than ‘int’.

    Use ‘int’ or ‘unsigned int’ instead.

    This is a portability problem because you don’t know the width of some abstract types like uid_t, gid_t, mode_t. So, instead of 

    mode = va_arg (ap, mode_t);

    you have to write 

    mode = (sizeof (mode_t) < sizeof (int)
        ? va_arg (ap, int)
        : va_arg (ap, mode_t));

Next: , Previous: , Up: Functions in <stdarg.h>   [Contents][Index]

10.42.2 va_copy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/va_copy.html

Gnulib module: stdarg-h

Portability problems fixed by Gnulib:

  • This macro is missing on some platforms: AIX 5.1 with cc or xlc, HP-UX 11 with cc.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdarg.h>   [Contents][Index]

10.42.3 va_end

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/va_end.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Previous: , Up: Functions in <stdarg.h>   [Contents][Index]

10.42.4 va_start

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/va_start.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.43 Functions in <stdatomic.h>

Next: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.1 atomic_compare_exchange_strong

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.4.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_compare_exchange_strong.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.2 atomic_compare_exchange_strong_explicit

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.4.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_compare_exchange_strong_explicit.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.3 atomic_compare_exchange_weak

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.4.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_compare_exchange_weak.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.4 atomic_compare_exchange_weak_explicit

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.4.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_compare_exchange_weak_explicit.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.5 atomic_exchange

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.3.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_exchange.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.6 atomic_exchange_explicit

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.3.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_exchange_explicit.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.7 atomic_fetch_add

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.5.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_fetch_add.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.8 atomic_fetch_add_explicit

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.5.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_fetch_add_explicit.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.9 atomic_fetch_and

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.5.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_fetch_and.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.10 atomic_fetch_and_explicit

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.5.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_fetch_and_explicit.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.11 atomic_fetch_or

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.5.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_fetch_or.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.12 atomic_fetch_or_explicit

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.5.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_fetch_or_explicit.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.13 atomic_fetch_sub

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.5.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_fetch_sub.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.14 atomic_fetch_sub_explicit

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.5.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_fetch_sub_explicit.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.15 atomic_fetch_xor

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.5.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_fetch_xor.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.16 atomic_fetch_xor_explicit

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.5.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_fetch_xor_explicit.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.17 atomic_flag_clear

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.8.2.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_flag_clear.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.18 atomic_flag_clear_explicit

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.8.2.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_flag_clear_explicit.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.19 atomic_flag_test_and_set

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.8.1.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_flag_test_and_set.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.20 atomic_flag_test_and_set_explicit

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.8.1.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_flag_test_and_set_explicit.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.21 atomic_init

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.2.1.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_init.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.22 atomic_is_lock_free

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.5.1.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_is_lock_free.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.23 atomic_load

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.2.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_load.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.24 atomic_load_explicit

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.2.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_load_explicit.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.25 atomic_signal_fence

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.4.2.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_signal_fence.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.26 atomic_store

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.1.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_store.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.27 atomic_store_explicit

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.7.1.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_store_explicit.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.28 atomic_thread_fence

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.4.1.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atomic_thread_fence.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Previous: , Up: Functions in <stdatomic.h>   [Contents][Index]

10.43.29 kill_dependency

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.17.3.1.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/kill_dependency.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc with GCC 4.8.x or clang 2.8, FreeBSD 6.4, NetBSD 7.0, OpenBSD 6.5, OpenBSD 6.9 with gcc, Minix 3.3.0, AIX 7.2 with xlc or xlclang, HP-UX 11.31, Solaris 11.3 with Oracle Studio 12.4 (Sun C 5.13), Cygwin 1.5.19, mingw, MSVC 14..

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.44 Functions and generic functions in <stdbit.h>

Next: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.1 stdc_bit_ceil

Documentation:
ISO C23 (latest free draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf) section 7.18.16.

Gnulib module: stdc_bit_ceil

Portability problems fixed by Gnulib:

  • This macro is missing on many platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.
  • This macro returns a value of the wrong type (e.g. unsigned long long instead of unsigned long) on some platforms: Solaris 11 OpenIndiana.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.2 stdc_bit_floor

Documentation:
ISO C23 (latest free draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf) section 7.18.15.

Gnulib module: stdc_bit_floor

Portability problems fixed by Gnulib:

  • This macro is missing on many platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.
  • This macro returns a value of the wrong type (e.g. unsigned long long instead of unsigned long) on some platforms: Solaris 11 OpenIndiana.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.3 stdc_bit_width

Documentation:
ISO C23 (latest free draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf) section 7.18.14.

Gnulib module: stdc_bit_width

Portability problems fixed by Gnulib:

  • This macro is missing on many platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.4 stdc_count_ones

Documentation:
ISO C23 (latest free draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf) section 7.18.12.

Gnulib module: stdc_count_ones

Portability problems fixed by Gnulib:

  • This macro is missing on many platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.5 stdc_count_zeros

Documentation:
ISO C23 (latest free draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf) section 7.18.11.

Gnulib module: stdc_count_zeros

Portability problems fixed by Gnulib:

  • This macro is missing on many platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.6 stdc_first_leading_one

Documentation:
ISO C23 (latest free draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf) section 7.18.8.

Gnulib module: stdc_first_leading_one

Portability problems fixed by Gnulib:

  • This macro is missing on many platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.7 stdc_first_leading_zero

Documentation:
ISO C23 (latest free draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf) section 7.18.7.

Gnulib module: stdc_first_leading_zero

Portability problems fixed by Gnulib:

  • This macro is missing on many platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.8 stdc_first_trailing_one

Documentation:
ISO C23 (latest free draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf) section 7.18.10.

Gnulib module: stdc_first_trailing_one

Portability problems fixed by Gnulib:

  • This macro is missing on many platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.9 stdc_first_trailing_zero

Documentation:
ISO C23 (latest free draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf) section 7.18.9.

Gnulib module: stdc_first_trailing_zero

Portability problems fixed by Gnulib:

  • This macro is missing on many platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.10 stdc_has_single_bit

Documentation:
ISO C23 (latest free draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf) section 7.18.13.

Gnulib module: stdc_has_single_bit

Portability problems fixed by Gnulib:

  • This macro is missing on many platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.11 stdc_leading_ones

Documentation:
ISO C23 (latest free draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf) section 7.18.4.

Gnulib module: stdc_leading_ones

Portability problems fixed by Gnulib:

  • This macro is missing on many platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.12 stdc_leading_zeros

Documentation:
ISO C23 (latest free draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf) section 7.18.3.

Gnulib module: stdc_leading_zeros

Portability problems fixed by Gnulib:

  • This macro is missing on many platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.13 stdc_load8_aligned_bes8

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.14 stdc_load8_aligned_bes16

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.15 stdc_load8_aligned_bes32

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.16 stdc_load8_aligned_bes64

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.17 stdc_load8_aligned_beu8

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.18 stdc_load8_aligned_beu16

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.19 stdc_load8_aligned_beu32

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.20 stdc_load8_aligned_beu64

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.21 stdc_load8_aligned_les8

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.22 stdc_load8_aligned_les16

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.23 stdc_load8_aligned_les32

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.24 stdc_load8_aligned_les64

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.25 stdc_load8_aligned_leu8

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.26 stdc_load8_aligned_leu16

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.27 stdc_load8_aligned_leu32

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.28 stdc_load8_aligned_leu64

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.29 stdc_load8_bes8

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.30 stdc_load8_bes16

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.31 stdc_load8_bes32

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.32 stdc_load8_bes64

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.33 stdc_load8_beu8

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.34 stdc_load8_beu16

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.35 stdc_load8_beu32

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.36 stdc_load8_beu64

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.37 stdc_load8_les8

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.38 stdc_load8_les16

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.39 stdc_load8_les32

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.40 stdc_load8_les64

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.41 stdc_load8_leu8

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.42 stdc_load8_leu16

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.43 stdc_load8_leu32

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.44 stdc_load8_leu64

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.21.

Gnulib module: stdc_load8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.45 stdc_memreverse8

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.19.

Gnulib module: stdc_memreverse8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.46 stdc_memreverse8u8

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.20.

Gnulib module: stdc_memreverse8u

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.47 stdc_memreverse8u16

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.20.

Gnulib module: stdc_memreverse8u

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.48 stdc_memreverse8u32

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.20.

Gnulib module: stdc_memreverse8u

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.49 stdc_memreverse8u64

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.20.

Gnulib module: stdc_memreverse8u

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.50 stdc_rotate_left

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.17.

Gnulib module: stdc_rotate_left

Portability problems fixed by Gnulib:

  • This macro and its associated functions is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.51 stdc_rotate_right

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.18.

Gnulib module: stdc_rotate_right

Portability problems fixed by Gnulib:

  • This macro and its associated functions is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.52 stdc_store8_aligned_bes8

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.53 stdc_store8_aligned_bes16

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.54 stdc_store8_aligned_bes32

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.55 stdc_store8_aligned_bes64

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.56 stdc_store8_aligned_beu8

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.57 stdc_store8_aligned_beu16

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.58 stdc_store8_aligned_beu32

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.59 stdc_store8_aligned_beu64

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.60 stdc_store8_aligned_les8

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.61 stdc_store8_aligned_les16

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.62 stdc_store8_aligned_les32

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.63 stdc_store8_aligned_les64

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.64 stdc_store8_aligned_leu8

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.65 stdc_store8_aligned_leu16

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.66 stdc_store8_aligned_leu32

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.67 stdc_store8_aligned_leu64

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8_aligned

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.68 stdc_store8_bes8

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.69 stdc_store8_bes16

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.70 stdc_store8_bes32

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.71 stdc_store8_bes64

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.72 stdc_store8_beu8

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.73 stdc_store8_beu16

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.74 stdc_store8_beu32

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.75 stdc_store8_beu64

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.76 stdc_store8_les8

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.77 stdc_store8_les16

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.78 stdc_store8_les32

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.79 stdc_store8_les64

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.80 stdc_store8_leu8

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.81 stdc_store8_leu16

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.82 stdc_store8_leu32

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.83 stdc_store8_leu64

Documentation:
ISO C2y (draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3783.pdf) section 7.18.22.

Gnulib module: stdc_store8

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.43, macOS 26, FreeBSD 15.0, NetBSD 10.0, OpenBSD 7.8, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.84 stdc_trailing_ones

Documentation:
ISO C23 (latest free draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf) section 7.18.6.

Gnulib module: stdc_trailing_ones

Portability problems fixed by Gnulib:

  • This macro is missing on many platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Previous: , Up: Functions and generic functions in <stdbit.h>   [Contents][Index]

10.44.85 stdc_trailing_zeros

Documentation:
ISO C23 (latest free draft https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf) section 7.18.5.

Gnulib module: stdc_trailing_zeros

Portability problems fixed by Gnulib:

  • This macro is missing on many platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 17, Android 15.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.45 Functions in <stdio.h>

Next: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.1 asprintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/asprintf.html

Documentation:

Gnulib module: vasprintf or vasprintf-posix or vasprintf-gnu

Portability problems fixed by either Gnulib module vasprintf or vasprintf-posix or vasprintf-gnu:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 10, mingw, MSVC 14.

Portability problems fixed by either Gnulib module vasprintf-posix or vasprintf-gnu:

  • This function does not support size specifiers as in C99 (hh, ll, j, t, z) on some platforms: Cygwin 1.5.24.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • printf "%f", "%e", "%g" of Infinity and NaN yields an incorrect result on some platforms: AIX 7.3, Solaris 11.4.
  • This function does not support the ‘a’ and ‘A’ directives on some platforms: FreeBSD 5.2.1, OpenBSD 4.0, Solaris 11.4, Cygwin 1.5.x.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support the ‘F’ directive on some platforms: NetBSD 3.0, Cygwin 1.5.x.
  • This function does not support the ‘ls’ directive on some platforms: OpenBSD 4.0, Cygwin 1.5.x, Haiku.
  • This function does not support precisions in the ‘ls’ directive correctly on some platforms: Solaris 11.4.
  • This function does not support format directives that access arguments in an arbitrary order, such as "%2$s", on some platforms: NetBSD 3.0.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag on some platforms: NetBSD 3.0, Cygwin 1.5.24.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not round the argument of the ‘a’ directive correctly on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4.
  • printf "%010f" of NaN and Infinity yields an incorrect result (padded with zeroes) on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, AIX 7.3, Solaris 11.4, Cygwin 1.5.x.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • This function produces wrong output for the ‘lc’ directive with a NUL wide character argument on some platforms: musl libc 1.2.4.
  • This function can crash in out-of-memory conditions on some platforms: FreeBSD 14.0, NetBSD 5.0.

Portability problems fixed by Gnulib module vasprintf-gnu:

  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.

Portability problems not fixed by Gnulib:

  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.2 clearerr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/clearerr.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.3 ctermid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ctermid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.4 dprintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dprintf.html

Gnulib module: dprintf or dprintf-posix or dprintf-gnu

Portability problems fixed by either Gnulib module dprintf or dprintf-posix or dprintf-gnu:

  • This function is missing on many non-glibc platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.5.x, mingw, MSVC 14.

Portability problems fixed by either Gnulib module dprintf-posix or dprintf-gnu:

  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • printf "%f", "%e", "%g" of Infinity and NaN yields an incorrect result on some platforms: AIX 7.3, Solaris 11.4.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not support the ‘a’ and ‘A’ directives on some platforms: Solaris 11.4.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support precisions in the ‘ls’ directive correctly on some platforms: Solaris 11.4.
  • This function does not round the argument of the ‘a’ directive correctly on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4.
  • printf "%010f" of NaN and Infinity yields an incorrect result (padded with zeroes, or wrong capitalization) on some platforms: AIX 7.3, Solaris 11.4.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • This function does not support precisions larger than 512 or 1024 in integer, floating-point and pointer output on some platforms: AIX 7.1.
  • This function produces wrong output for the ‘lc’ directive with a NUL wide character argument on some platforms: musl libc 1.2.4.

Portability problems fixed by Gnulib module dprintf-gnu:

  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.

Portability problems fixed by either Gnulib module dprintf-posix or dprintf-gnu and additionally the Gnulib module printf-with-n-directive:

  • This function does not support the ‘n’ directive on some platforms: glibc when used with _FORTIFY_SOURCE >= 2 (set by default on Ubuntu), macOS 14, OpenBSD, Android.

Portability problems not fixed by Gnulib:

  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.
  • Formatting noncanonical ‘long double’ numbers produces nonmeaningful results on some platforms: glibc and others, on x86, x86_64, IA-64 CPUs.
  • When formatting an integer with grouping flag, this function inserts thousands separators even in the "C" locale on some platforms: NetBSD 5.1.
  • On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.5 fclose

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fclose.html

Gnulib module: fclose

Portability problems fixed by Gnulib:

  • On some platforms, this function fails to set the file position of a seekable input stream to the byte after the last one actually read: glibc 2.34, FreeBSD, AIX 7.2.
  • This function crashes if the stream’s file descriptor has already been closed on some platforms: MSVC 14.
  • On Windows platforms (excluding Cygwin), socket and accept followed by fdopen do not return streams that can be closed by fclose.

Portability problems not fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.6 fdopen

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fdopen.html

Gnulib module: fdopen

Portability problems fixed by Gnulib:

  • This function crashes when invoked with invalid arguments on some platforms: MSVC 14.
  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.7 feof

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/feof.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.8 ferror

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ferror.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.9 fflush

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fflush.html

Gnulib module: fflush

Portability problems fixed by Gnulib:

  • fflush followed by fseek or fseeko, applied to an input stream, should have the effect of positioning the underlying file descriptor. It doesn’t do this on some platforms: glibc 2.34, FreeBSD 14.0, and others.
  • fflush on an input stream changes the position of the stream to the end of the previous buffer, on some platforms: mingw, MSVC 14.
  • fflush on an input stream right after ungetc does not discard the ungetc buffer, on some platforms: macOS 14, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Cygwin 1.5.25-10.
  • fflush fails with EBADF if the stream is not open for writing: NetBSD 10.0, OpenBSD 7.9.

Portability problems not fixed by Gnulib:

  • fflush, ftell, ftello, fgetpos behave incorrectly on input streams that are opened in O_TEXT mode and whose contents contains Unix line terminators (LF), on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • This function crashes if the stream’s file descriptor has already been closed, if MSVC_INVALID_PARAMETER_HANDLING is HAIRY_LIBRARY_HANDLING or SANE_LIBRARY_HANDLING, on some platforms: MSVC 14.
  • fflush on an input stream right after ungetc does not discard the ungetc buffer, on some platforms: AIX 5.1, HP-UX 11, Solaris 11 2010-11, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.10 fgetc

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fgetc.html

Gnulib module: stdio-h, nonblocking

Portability problems fixed by Gnulib module stdio-h, together with module nonblocking:

  • When reading from a non-blocking pipe whose buffer is empty, this function fails with errno being set to EINVAL instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • C99 and POSIX.1-2001 and later require end-of-file to be sticky, that is, they require this function to act as if it reads end-of-file if feof would return nonzero. However, on some systems this function attempts to read from the underlying file descriptor even if the stream’s end-of-file indicator is set. These systems include glibc and default Solaris.
  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • This function crashes if the stream’s file descriptor has already been closed, if MSVC_INVALID_PARAMETER_HANDLING is HAIRY_LIBRARY_HANDLING or SANE_LIBRARY_HANDLING, on some platforms: MSVC 14.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.11 fgetpos

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fgetpos.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, this function may not work correctly on files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

  • fflush, ftell, ftello, fgetpos behave incorrectly on input streams that are opened in O_TEXT mode and whose contents contains Unix line terminators (LF), on some platforms: mingw, MSVC 14.
  • This function mistakenly succeeds on pipes on some platforms: mingw 10.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.12 fgets

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fgets.html

Gnulib module: stdio-h, nonblocking

Portability problems fixed by Gnulib module stdio-h, together with module nonblocking:

  • When reading from a non-blocking pipe whose buffer is empty, this function fails with errno being set to EINVAL instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • C99 and POSIX.1-2001 and later require end-of-file to be sticky, that is, they require this function to act as if it reads end-of-file if feof would return nonzero. However, on some systems this function attempts to read from the underlying file descriptor even if the stream’s end-of-file indicator is set. These systems include glibc and default Solaris.
  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.13 fileno

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fileno.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.14 flockfile

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/flockfile.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.15 fmemopen

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fmemopen.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.5.x, mingw, MSVC 14, Android 5.1.

An alternative to the fmemopen function is the Gnulib module sf-istream.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.16 fopen

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fopen.html

Gnulib module: fopen or fopen-gnu

Portability problems fixed by either Gnulib module fopen or fopen-gnu:

  • This function does not fail when the file name argument ends in a slash and (without the slash) names a nonexistent file or a file that is not a directory, on some platforms: HP-UX 11.00, AIX 7.1, Solaris 9.
  • On platforms where off_t is a 32-bit type, fopen may not work correctly with files 2 GiB and larger. See Large File Support.
  • On Windows platforms (excluding Cygwin), this function does usually not recognize the /dev/null filename.

Portability problems fixed by Gnulib module fopen-gnu:

  • This function does not support the mode character ‘x’ (corresponding to O_EXCL), introduced in ISO C11, on some platforms: FreeBSD 8.2, NetBSD 6.1, OpenBSD 5.6, Minix 3.2, AIX 6.1, HP-UX 11.31, Solaris 11.3, Cygwin 1.7.16 (2012), mingw with MSVCRT, MSVC 14.
  • This function does not support the mode character ‘e’ (corresponding to O_CLOEXEC), introduced in POSIX.1-2024, on some platforms: glibc 2.6, macOS 14, FreeBSD 9.0, NetBSD 5.1, OpenBSD 5.6, Minix 3.2, AIX 7.2, HP-UX 11.31, Solaris 11.3, Cygwin 1.7.16 (2012), mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • On Windows, this function returns a file stream in “text” mode by default; this means that it translates '\n' to CR/LF by default. Use the "b" flag if you need reliable binary I/O.
  • On Windows platforms (excluding Cygwin), this function fails to open directories for reading. Such streams have implementation-defined semantics on other platforms. To avoid directory streams with a consistent error message, use fstat after open and fdopen, rather than fopen and fileno.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.17 fprintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fprintf.html

Gnulib module: fprintf-posix or fprintf-gnu or stdio-h, nonblocking, sigpipe

Portability problems fixed by either Gnulib module stdio-h or fprintf-posix or fprintf-gnu:

  • This function does not support non-ASCII characters in double-byte encoding, corresponding to the locale, on some platforms: mingw with __USE_MINGW_ANSI_STDIO in combination with msvcrt, when the output goes to a Windows console.

Portability problems fixed by either Gnulib module fprintf-posix or fprintf-gnu:

  • This function does not support size specifiers as in C99 (hh, ll, j, t, z) on some platforms: AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.24, old mingw, MSVC 9.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • printf of ‘long double’ numbers is unsupported on some platforms: mingw, MSVC 14.
  • printf "%f", "%e", "%g" of Infinity and NaN yields an incorrect result on some platforms: AIX 7.3, Solaris 11.4, mingw, MSVC 14.
  • This function does not support the ‘a’ and ‘A’ directives on some platforms: FreeBSD 5.2.1, OpenBSD 4.0, AIX 5.2, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support the ‘F’ directive on some platforms: NetBSD 3.0, AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘ls’ directive on some platforms: OpenBSD 4.0, Cygwin 1.5.x, Haiku.
  • This function does not support precisions in the ‘ls’ directive correctly on some platforms: Solaris 11.4.
  • This function does not support format directives that access arguments in an arbitrary order, such as "%2$s", on some platforms: NetBSD 3.0, mingw, MSVC 14.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag on some platforms: NetBSD 3.0, Cygwin 1.5.24, mingw, MSVC 14.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not round the argument of the ‘a’ directive correctly on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4.
  • printf "%010f" of NaN and Infinity yields an incorrect result (padded with zeroes, or wrong capitalization) on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, AIX 7.3, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC/clang.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • This function does not support precisions larger than 512 or 1024 in integer, floating-point and pointer output on some platforms: AIX 7.1, Solaris 10/x86, mingw, MSVC/clang.
  • This function mishandles large floating point precisions (for example, formatting 1.0 with ‘"%.511f"’) on some platforms: Solaris 10.
  • This function produces wrong output for the ‘lc’ directive with a NUL wide character argument on some platforms: musl libc 1.2.4.
  • This function can crash in out-of-memory conditions on some platforms: FreeBSD 14.0, NetBSD 5.0.

Portability problems fixed by Gnulib module fprintf-gnu:

  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.

Portability problems fixed by either Gnulib module fprintf-posix or fprintf-gnu and additionally the Gnulib module printf-with-n-directive:

  • This function does not support the ‘n’ directive on some platforms: glibc when used with _FORTIFY_SOURCE >= 2 (set by default on Ubuntu), macOS 14, OpenBSD, MSVC 14, Android.

Portability problems fixed by Gnulib module stdio-h or fprintf-posix or fprintf-gnu, together with module nonblocking:

  • When writing to a non-blocking pipe whose buffer is full, this function fails with errno being set to ENOSPC instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems fixed by Gnulib module stdio-h or fprintf-posix or fprintf-gnu, together with module sigpipe:

  • When writing to a pipe with no readers, this function fails, instead of obeying the current SIGPIPE handler, on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.
  • Formatting noncanonical ‘long double’ numbers produces nonmeaningful results on some platforms: glibc and others, on x86, x86_64, IA-64 CPUs.
  • When formatting an integer with grouping flag, this function inserts thousands separators even in the "C" locale on some platforms: NetBSD 5.1.
  • Attempting to write to a read-only stream fails with EOF but does not set the error flag for ferror on some platforms: glibc 2.13, cygwin 1.7.9.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.18 fputc

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fputc.html

Gnulib module: stdio-h, nonblocking, sigpipe

Portability problems fixed by Gnulib module stdio-h, together with module nonblocking:

  • When writing to a non-blocking pipe whose buffer is full, this function fails with errno being set to ENOSPC instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems fixed by Gnulib module stdio-h, together with module sigpipe:

  • When writing to a pipe with no readers, this function fails, instead of obeying the current SIGPIPE handler, on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • This function fails and produces garbled output when invoked twice, for outputting a non-ASCII character in double-byte encoding, corresponding to the locale, on some platforms: mingw in combination with msvcrt, when the output goes to a Windows console.
  • On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.
  • This function crashes if the stream’s file descriptor has already been closed, if MSVC_INVALID_PARAMETER_HANDLING is HAIRY_LIBRARY_HANDLING or SANE_LIBRARY_HANDLING, on some platforms: MSVC 14.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.19 fputs

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fputs.html

Gnulib module: stdio-h, nonblocking, sigpipe

Portability problems fixed by Gnulib module stdio-h, together with module nonblocking:

  • When writing to a non-blocking pipe whose buffer is full, this function fails with errno being set to ENOSPC instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems fixed by Gnulib module stdio-h, together with module sigpipe:

  • When writing to a pipe with no readers, this function fails, instead of obeying the current SIGPIPE handler, on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.20 fread

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fread.html

Gnulib module: stdio-h, nonblocking

Portability problems fixed by Gnulib module stdio-h, together with module nonblocking:

  • When reading from a non-blocking pipe whose buffer is empty, this function fails with errno being set to EINVAL instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • C99 and POSIX.1-2001 and later require end-of-file to be sticky, that is, they require this function to act as if it reads end-of-file if feof would return nonzero. However, on some systems this function attempts to read from the underlying file descriptor even if the stream’s end-of-file indicator is set. These systems include glibc and default Solaris.
  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • This function crashes if the stream’s file descriptor has already been closed, if MSVC_INVALID_PARAMETER_HANDLING is HAIRY_LIBRARY_HANDLING or SANE_LIBRARY_HANDLING, on some platforms: MSVC 14.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.21 freopen

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/freopen.html

Gnulib module: freopen

Portability problems fixed by Gnulib:

  • On some platforms, if stream does not already have an open file descriptor, freopen returns the stream without opening the file: glibc 2.24.
  • On platforms where off_t is a 32-bit type, freopen may not work correctly with files 2 GiB and larger. See Large File Support.
  • On Windows platforms (excluding Cygwin), this function does usually not recognize the /dev/null filename.

Portability problems not fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • This function does not support a NULL file name argument on some platforms: OpenBSD 4.9, AIX 7.1, HP-UX 11.23, Solaris 10, mingw, MSVC 14.
  • This function does not fail when the file name argument ends in a slash and (without the slash) names a nonexistent file or a file that is not a directory, on some platforms: HP-UX 11.00, Solaris 9.
  • Applications should not assume that fileno(f) will be the same before and after a call to freopen(name,mode,f). However, the module freopen-safer can at least protect stdin, stdout, and stderr.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.22 fscanf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fscanf.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fscanf.html

Gnulib module: stdio-h, nonblocking

Portability problems fixed by Gnulib module stdio-h, together with module nonblocking:

  • When reading from a non-blocking pipe whose buffer is empty, this function fails with errno being set to EINVAL instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • C99 and POSIX.1-2001 and later require end-of-file to be sticky, that is, they require this function to act as if it reads end-of-file if feof would return nonzero. However, on some systems this function attempts to read from the underlying file descriptor even if the stream’s end-of-file indicator is set. These systems include glibc and default Solaris.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.38, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.2, AIX 7.2, HP-UX 11, Solaris 11.4, Cygwin 2.9.0, mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • On Windows, this function doesn’t support the hh, ll, j, t, z size specifiers.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.23 fseek

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fseek.html

Gnulib module: fseek

Portability problems fixed by Gnulib:

  • This function mistakenly succeeds on pipes on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • On platforms where long is a 32-bit type, fseek does not work correctly with files 2 GiB and larger, even when the AC_SYS_LARGEFILE macro is used. The fix is to use fseeko instead.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.24 fseeko

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fseeko.html

Gnulib module: fseeko

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • The declaration of fseeko in <stdio.h> is not enabled by default on some platforms: glibc 2.3.6.
  • This function fails on seekable stdin, stdout, and stderr: cygwin <= 1.5.24.
  • On platforms where off_t is a 32-bit type, fseeko does not work correctly with files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.25 fsetpos

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fsetpos.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, this function may not work correctly on files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.26 ftell

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ftell.html

Gnulib module: ftell

Portability problems fixed by Gnulib:

  • This function mistakenly succeeds on pipes on some platforms: mingw, MSVC 14.
  • This function produces incorrect results after putc that followed a getc call that reached EOF on some platforms: Solaris 11 2010-11.
  • This function, when invoked after ungetc, throws away the ungetc buffer, changes the stream’s file position, and returns the wrong position on some platforms: macOS 10.15, 11, 12.
  • This function mistakenly succeeds on pipes on some platforms: mingw 10.

Portability problems not fixed by Gnulib:

  • This function produces incorrect results immediately after fseek on some platforms: HP-UX 11.
  • fflush, ftell, ftello, fgetpos behave incorrectly on input streams that are opened in O_TEXT mode and whose contents contains Unix line terminators (LF), on some platforms: mingw, MSVC 14.
  • On platforms where long is a 32-bit type, ftell does not work correctly with files 2 GiB and larger, even when the AC_SYS_LARGEFILE macro is used. The fix is to use ftello instead.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.27 ftello

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ftello.html

Gnulib module: ftello

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • The declaration of ftello in <stdio.h> is not enabled by default on some platforms: glibc 2.3.6.
  • This function produces incorrect results after putc that followed a getc call that reached EOF on some platforms: Solaris 11 2010-11.
  • This function, when invoked after ungetc, throws away the ungetc buffer, changes the stream’s file position, and returns the wrong position on some platforms: macOS 10.15, 11, 12.
  • This function fails on seekable stdin, stdout, and stderr: cygwin <= 1.5.24.
  • This function mistakenly succeeds on pipes on some platforms: mingw 10.
  • On platforms where off_t is a 32-bit type, ftello does not work correctly with files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function produces incorrect results immediately after fseek on some platforms: HP-UX 11.
  • fflush, ftell, ftello, fgetpos behave incorrectly on input streams that are opened in O_TEXT mode and whose contents contains Unix line terminators (LF), on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.28 ftrylockfile

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ftrylockfile.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.29 funlockfile

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/funlockfile.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.30 fwrite

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fwrite.html

Gnulib module: stdio-h, nonblocking, sigpipe

Portability problems fixed by Gnulib module stdio-h:

  • This function fails and produces no output when the argument string starts with a non-ASCII character in double-byte encoding, corresponding to the locale, on some platforms: mingw in combination with msvcrt, when the output goes to a Windows console.

Portability problems fixed by Gnulib module stdio-h, together with module nonblocking:

  • When writing to a non-blocking pipe whose buffer is full, this function fails with errno being set to ENOSPC instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems fixed by Gnulib module stdio-h, together with module sigpipe:

  • When writing to a pipe with no readers, this function fails, instead of obeying the current SIGPIPE handler, on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.
  • This function crashes if the stream’s file descriptor has already been closed, if MSVC_INVALID_PARAMETER_HANDLING is HAIRY_LIBRARY_HANDLING or SANE_LIBRARY_HANDLING, on some platforms: MSVC 14.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.31 getc

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getc.html

Gnulib module: stdio-h, nonblocking

Portability problems fixed by Gnulib module stdio-h, together with module nonblocking:

  • When reading from a non-blocking pipe whose buffer is empty, this function fails with errno being set to EINVAL instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • C99 and POSIX.1-2001 and later require end-of-file to be sticky, that is, they require this function to act as if it reads end-of-file if feof would return nonzero. However, on some systems this function attempts to read from the underlying file descriptor even if the stream’s end-of-file indicator is set. These systems include glibc and default Solaris.
  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.32 getc_unlocked

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getc_unlocked.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.33 getchar

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getchar.html

Gnulib module: stdio-h, nonblocking

Portability problems fixed by Gnulib module stdio-h, together with module nonblocking:

  • When reading from a non-blocking pipe whose buffer is empty, this function fails with errno being set to EINVAL instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • C99 and POSIX.1-2001 and later require end-of-file to be sticky, that is, they require this function to act as if it reads end-of-file if feof would return nonzero. However, on some systems this function attempts to read from the underlying file descriptor even if the stream’s end-of-file indicator is set. These systems include glibc and default Solaris.
  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.34 getchar_unlocked

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getchar_unlocked.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.35 getdelim

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getdelim.html

Gnulib module: getdelim

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, mingw, MSVC 14, Android 4.2.
  • This function makes out-of-bounds reads on some platforms: macOS 10.13.
  • This function crashes when passed a pointer to a NULL buffer together with a pointer to a non-zero buffer size on some platforms: FreeBSD 8.0.

Portability problems not fixed by Gnulib:

  • This function has quadratic running time for long lines on some platforms: uClibc 0.9.31.
  • This function does not NUL terminate the buffer when the first character read is EOF on some platforms: glibc 2.42.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.36 getline

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getline.html

Gnulib module: getline

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, mingw, MSVC 14, Android 4.2.
  • This function is missing a declaration on some platforms: AIX 7.1.
  • Some platforms provide a function by this name but with the wrong signature, for example in -linet.
  • This function crashes when passed a pointer to a NULL buffer together with a pointer to a non-zero buffer size on some platforms: FreeBSD 8.0.

Portability problems not fixed by Gnulib:

  • This function has quadratic running time for long lines on some platforms: uClibc 0.9.31.
  • This function does not NUL terminate the buffer when the first character read is EOF on some platforms: glibc 2.42.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.37 open_memstream

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/open_memstream.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 7.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.5.x, mingw, MSVC 14, Android 5.1.

An alternative to the open_memstream function is the Gnulib module string-buffer.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.38 pclose

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pclose.html

Gnulib module: pclose

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.39 perror

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/perror.html

Gnulib module: perror

Portability problems fixed by Gnulib:

  • This function does not support the error values that are specified by POSIX but not defined by the system, on some platforms: OpenBSD 4.0, Cygwin 1.5.x, mingw, MSVC 14.
  • This function treats errno of 0 like failure, although POSIX requires that the message declare it as a success, on some platforms: FreeBSD 8.2, OpenBSD 4.7, macOS 14.
  • This function clobbers the strerror buffer on some platforms: Cygwin 1.7.9, Android 11.
  • This function fails to print a useful a string for out-of-range integers on some platforms: HP-UX 11.

Portability problems not fixed by Gnulib:

  • POSIX requires that this function set the stream error bit (detected by ferror) on write failure, but not all platforms do this: glibc 2.13, cygwin 1.7.9.
  • POSIX requires that this function not alter stream orientation, but the gnulib replacement locks in byte orientation and fails on wide character streams.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.40 popen

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/popen.html

Gnulib module: popen

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: MSVC 14.
  • Some platforms start the child with closed stdin or stdout if the standard descriptors were closed in the parent: Cygwin 1.5.x.
  • This function hangs if called with closed stdin or stdout on some platforms: OS/2 kLIBC.

Portability problems not fixed by Gnulib:

  • On native Windows platforms, this functions terminates the current process with exit code 127 if the environment variable COMSPEC is not set.
  • Some platforms mistakenly set the close-on-exec bit, then if it is cleared by the application, the platform then leaks file descriptors from earlier popen calls into subsequent popen children: Cygwin 1.5.x.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.41 printf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/printf.html

Gnulib module: printf-posix or printf-gnu or stdio-h, nonblocking, sigpipe

Portability problems fixed by either Gnulib module stdio-h or fprintf-posix or fprintf-gnu:

  • This function does not support non-ASCII characters in double-byte encoding, corresponding to the locale, on some platforms: mingw with __USE_MINGW_ANSI_STDIO in combination with msvcrt, when the output goes to a Windows console.

Portability problems fixed by either Gnulib module printf-posix or printf-gnu:

  • This function does not support size specifiers as in C99 (hh, ll, j, t, z) on some platforms: AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.24, old mingw, MSVC 9.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • printf of ‘long double’ numbers is unsupported on some platforms: mingw, MSVC 14.
  • printf "%f", "%e", "%g" of Infinity and NaN yields an incorrect result on some platforms: AIX 7.3, Solaris 11.4, mingw, MSVC 14.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not support the ‘a’ and ‘A’ directives on some platforms: FreeBSD 5.2.1, OpenBSD 4.0, AIX 5.2, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support the ‘F’ directive on some platforms: NetBSD 3.0, AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘ls’ directive on some platforms: OpenBSD 4.0, Cygwin 1.5.x, Haiku.
  • This function does not support precisions in the ‘ls’ directive correctly on some platforms: Solaris 11.4.
  • This function does not support format directives that access arguments in an arbitrary order, such as "%2$s", on some platforms: NetBSD 3.0, mingw, MSVC 14.
  • This function doesn’t support the ' flag on some platforms: NetBSD 3.0, Cygwin 1.5.24, mingw, MSVC 14.
  • This function does not round the argument of the ‘a’ directive correctly on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4.
  • printf "%010f" of NaN and Infinity yields an incorrect result (padded with zeroes, or wrong capitalization) on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, AIX 7.3, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC/clang.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • This function does not support precisions larger than 512 or 1024 in integer, floating-point and pointer output on some platforms: AIX 7.1, Solaris 10/x86, mingw, MSVC/clang.
  • This function mishandles large floating point precisions (for example, formatting 1.0 with ‘"%.511f"’) on some platforms: Solaris 10.
  • This function produces wrong output for the ‘lc’ directive with a NUL wide character argument on some platforms: musl libc 1.2.4.
  • This function can crash in out-of-memory conditions on some platforms: FreeBSD 14.0, NetBSD 5.0.
  • This function returns zero instead of a negative number after running out of memory: OpenBSD 7.8.

Portability problems fixed by Gnulib module printf-gnu:

  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.

Portability problems fixed by either Gnulib module printf-posix or printf-gnu and additionally the Gnulib module printf-with-n-directive:

  • This function does not support the ‘n’ directive on some platforms: glibc when used with _FORTIFY_SOURCE >= 2 (set by default on Ubuntu), macOS 14, OpenBSD, MSVC 14, Android.

Portability problems fixed by Gnulib module stdio-h or printf-posix or printf-gnu, together with module nonblocking:

  • When writing to a non-blocking pipe whose buffer is full, this function fails with errno being set to ENOSPC instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems fixed by Gnulib module stdio-h or printf-posix or printf-gnu, together with module sigpipe:

  • When writing to a pipe with no readers, this function fails, instead of obeying the current SIGPIPE handler, on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.
  • Formatting noncanonical ‘long double’ numbers produces nonmeaningful results on some platforms: glibc and others, on x86, x86_64, IA-64 CPUs.
  • When formatting an integer with grouping flag, this function inserts thousands separators even in the "C" locale on some platforms: NetBSD 5.1.
  • Attempting to write to a read-only stream fails with EOF but does not set the error flag for ferror on some platforms: glibc 2.13, cygwin 1.7.9.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.42 putc

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/putc.html

Gnulib module: stdio-h, nonblocking, sigpipe

Portability problems fixed by Gnulib module stdio-h, together with module nonblocking:

  • When writing to a non-blocking pipe whose buffer is full, this function fails with errno being set to ENOSPC instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems fixed by Gnulib module stdio-h, together with module sigpipe:

  • When writing to a pipe with no readers, this function fails, instead of obeying the current SIGPIPE handler, on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • This function fails and produces garbled output when invoked twice, for outputting a non-ASCII character in double-byte encoding, corresponding to the locale, on some platforms: mingw in combination with msvcrt, when the output goes to a Windows console.
  • On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.43 putc_unlocked

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/putc_unlocked.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.44 putchar

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/putchar.html

Gnulib module: stdio-h, nonblocking, sigpipe

Portability problems fixed by Gnulib module stdio-h, together with module nonblocking:

  • When writing to a non-blocking pipe whose buffer is full, this function fails with errno being set to ENOSPC instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems fixed by Gnulib module stdio-h, together with module sigpipe:

  • When writing to a pipe with no readers, this function fails, instead of obeying the current SIGPIPE handler, on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.45 putchar_unlocked

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/putchar_unlocked.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.46 puts

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/puts.html

Gnulib module: stdio-h, nonblocking, sigpipe

Portability problems fixed by Gnulib module stdio-h, together with module nonblocking:

  • When writing to a non-blocking pipe whose buffer is full, this function fails with errno being set to ENOSPC instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems fixed by Gnulib module stdio-h, together with module sigpipe:

  • When writing to a pipe with no readers, this function fails, instead of obeying the current SIGPIPE handler, on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.47 remove

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/remove.html

Gnulib module: remove

Portability problems fixed by Gnulib:

  • This function fails to reject trailing slashes on non-directories on some platforms: FreeBSD 7.2, Solaris 9.
  • This function mistakenly removes a directory with remove("dir/./") on some platforms: Cygwin 1.5.x.
  • This function does not remove empty directories on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.48 rename

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/rename.html

Gnulib module: rename

Portability problems fixed by Gnulib:

  • This function does not allow trailing slashes when creating a destination directory, as in rename("dir","new/"): NetBSD 1.6.
  • This function does not reject trailing slashes on the destination for non-directories on some platforms, as in rename("file","new/"): AIX 7.1, Solaris 11.3, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not reject trailing slashes on symlinks to non-directories on some platforms, as in rename("link-to-file/","f"): FreeBSD 7.2.
  • This function ignores trailing slashes on symlinks on some platforms, such that rename("link/","new") corrupts link: Solaris 9.
  • This function incorrectly reduces the link count when comparing two spellings of a hard link on some platforms: NetBSD 1.6, Cygwin 1.5.x.
  • This function will not always replace an existing destination on some platforms: Cygwin 1.5.x, mingw, MSVC 14. However, the replacement is not atomic for directories, and may end up losing the empty destination if the source could not be renamed.
  • This function mistakenly allows names ending in ‘.’ or ‘..’ on some platforms: Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not reject attempts to rename existing directories and non-directories onto one another on some platforms: Cygwin 1.5.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • POSIX requires that rename("symlink-to-dir/","dir2") rename dir and leave symlink-to-dir dangling; likewise, it requires that rename("dir","dangling/") rename dir so that dangling is no longer a dangling symlink. This behavior is counter-intuitive, so on some systems, rename fails with ENOTDIR if either argument is a symlink with a trailing slash: glibc, OpenBSD, Cygwin 1.7.
  • POSIX requires that rename do nothing and return 0 if the source and destination are hard links to the same file. This behavior is counterintuitive, and on some systems renameat is a no-op in this way only if the source and destination identify the same directory entry. On these systems, for example, although renaming ./f to f is a no-op, renaming f to g deletes f when f and g are hard links to the same file: NetBSD 7.0.
  • After renaming a non-empty directory over an existing empty directory, the old directory name is still visible through the stat function for 30 seconds after the rename, on NFS file systems, on some platforms: Linux 2.6.18.
  • This function will not rename a source that is currently opened by any process: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.49 renameat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/renameat.html

Gnulib module: renameat

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.5.x, mingw, MSVC 14. But the replacement function is not safe to be used in libraries and is not thread-safe.
  • This function is declared in <unistd.h>, not in <stdio.h>, on some platforms: NetBSD 7.0, Solaris 11.4.
  • This function is declared in <sys/stat.h>, not in <stdio.h>, on some platforms: Android 4.3.
  • This function does not reject trailing slashes on non-directories on some platforms, as in renameat(fd,"file",fd,"new/"): Solaris 11.4.
  • This function ignores trailing slashes on symlinks on some platforms, such that renameat(fd,"link/",fd,"new") corrupts link: Solaris 9.
  • renameat (AT_FDCWD, "file", AT_FDCWD, "new/") succeeds instead of failing and setting errno to ENOTDIR, on some platforms: GNU/Hurd with glibc 2.41.
  • renameat (ATFDCWD, "dir", AT_FDCWD, "new/") fails with errno set to ENOENT, on some platforms: GNU/Hurd with glibc 2.42.
  • renameat (ATFDCWD, "dir/", AT_FDCWD, "new") fails with errno set to ENOTDIR, on some platforms: GNU/Hurd with glibc 2.42.

Portability problems not fixed by Gnulib:

  • POSIX requires that renameat(fd,"symlink-to-dir/",fd,"dir2") rename dir and leave symlink-to-dir dangling; likewise, it requires that renameat(fd,"dir",fd,"dangling/") rename dir so that dangling is no longer a dangling symlink. This behavior is counter-intuitive, so on some systems, renameat fails with ENOTDIR if either argument is a symlink with a trailing slash: glibc, OpenBSD, Cygwin 1.7.
  • POSIX requires that renameat do nothing and return 0 if the source and destination are hard links to the same file. This behavior is counterintuitive, and on some systems renameat is a no-op in this way only if the source and destination identify the same directory entry. On these systems, for example, although renaming ./f to f is a no-op, renaming f to g deletes f when f and g are hard links to the same file: NetBSD 7.0.
  • After renaming a non-empty directory over an existing empty directory, the old directory name is still visible through the stat function for 30 seconds after the rename, on NFS file systems, on some platforms: Linux 2.6.18.
  • This function will not rename a source that is currently opened by any process: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.50 rewind

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/rewind.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.51 scanf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/scanf.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-scanf.html

Gnulib module: stdio-h, nonblocking

Portability problems fixed by Gnulib module stdio-h, together with module nonblocking:

  • When reading from a non-blocking pipe whose buffer is empty, this function fails with errno being set to EINVAL instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • C99 and POSIX.1-2001 and later require end-of-file to be sticky, that is, they require this function to act as if it reads end-of-file if feof would return nonzero. However, on some systems this function attempts to read from the underlying file descriptor even if the stream’s end-of-file indicator is set. These systems include glibc and default Solaris.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.38, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.2, AIX 7.2, HP-UX 11, Solaris 11.4, Cygwin 2.9.0, mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • On Windows, this function doesn’t support the hh, ll, j, t, z size specifiers.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.52 setbuf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setbuf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.53 setvbuf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setvbuf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • On Windows platforms (excluding Cygwin), _IOLBF (line-buffering) is treated as if it were _IOFBF (full buffering), possibly with a warning generated.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.54 snprintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/snprintf.html

Gnulib module: snprintf or snprintf-posix or snprintf-gnu

Portability problems fixed by either Gnulib module snprintf or snprintf-posix or snprintf-gnu:

  • This function is missing on some platforms: MSVC 14.
  • This function does not support format directives that access arguments in an arbitrary order, such as "%2$s", on some platforms: NetBSD 3.0, mingw.
  • This function does not return a byte count as specified in C99 on some platforms: HP-UX 11, Solaris 9, mingw.

Portability problems fixed by either Gnulib module snprintf-posix or snprintf-gnu:

  • This function does not support size specifiers as in C99 (hh, ll, j, t, z) on some platforms: AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.24, old mingw, MSVC 9.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • printf of ‘long double’ numbers is unsupported on some platforms: mingw, MSVC 14.
  • printf "%f", "%e", "%g" of Infinity and NaN yields an incorrect result on some platforms: AIX 7.3, Solaris 11.4, mingw, MSVC 14.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not support the ‘a’ and ‘A’ directives on some platforms: FreeBSD 5.2.1, OpenBSD 4.0, AIX 5.2, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support the ‘F’ directive on some platforms: NetBSD 3.0, AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘ls’ directive on some platforms: OpenBSD 4.0, Cygwin 1.5.x, Haiku.
  • This function does not support precisions in the ‘ls’ directive correctly on some platforms: Solaris 11.4.
  • This function doesn’t support the ' flag on some platforms: NetBSD 3.0, Cygwin 1.5.24, mingw, MSVC 14.
  • This function does not round the argument of the ‘a’ directive correctly on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4.
  • printf "%010f" of NaN and Infinity yields an incorrect result (padded with zeroes, or wrong capitalization) on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, AIX 7.3, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC/clang.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • This function does not support precisions larger than 512 or 1024 in integer, floating-point and pointer output on some platforms: AIX 7.1, Solaris 10/x86, mingw, MSVC/clang.
  • This function mishandles large floating point precisions (for example, formatting 1.0 with ‘"%.511f"’) on some platforms: Solaris 10.
  • This function produces wrong output for the ‘lc’ directive with a NUL wide character argument on some platforms: musl libc 1.2.4.
  • This function can crash in out-of-memory conditions on some platforms: FreeBSD 14.0, NetBSD 5.0.
  • This function does not truncate the result as specified in C99 on some platforms: mingw, MSVC 14.
  • This function does not fully support the ‘n’ directive on some platforms: HP-UX 11, mingw.

Portability problems fixed by Gnulib module snprintf-gnu:

  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.

Portability problems fixed by either Gnulib module snprintf-posix or snprintf-gnu and additionally the Gnulib module printf-with-n-directive:

  • This function does not support the ‘n’ directive on some platforms: glibc when used with _FORTIFY_SOURCE >= 2 (set by default on Ubuntu), macOS 14, OpenBSD, MSVC 14, Android.

Portability problems not fixed by Gnulib:

  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.
  • Formatting noncanonical ‘long double’ numbers produces nonmeaningful results on some platforms: glibc and others, on x86, x86_64, IA-64 CPUs.
  • When formatting an integer with grouping flag, this function inserts thousands separators even in the "C" locale on some platforms: NetBSD 5.1.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.55 sprintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sprintf.html

Gnulib module: sprintf-posix or sprintf-gnu

Portability problems fixed by either Gnulib module sprintf-posix or sprintf-gnu:

  • This function does not support size specifiers as in C99 (hh, ll, j, t, z) on some platforms: AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.24, old mingw, MSVC 9.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • printf of ‘long double’ numbers is unsupported on some platforms: mingw, MSVC 14.
  • printf "%f", "%e", "%g" of Infinity and NaN yields an incorrect result on some platforms: AIX 7.3, Solaris 11.4, mingw, MSVC 14.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not support the ‘a’ and ‘A’ directives on some platforms: FreeBSD 5.2.1, OpenBSD 4.0, AIX 5.2, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support the ‘F’ directive on some platforms: NetBSD 3.0, AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘ls’ directive on some platforms: OpenBSD 4.0, Cygwin 1.5.x, Haiku.
  • This function does not support precisions in the ‘ls’ directive correctly on some platforms: Solaris 11.4.
  • This function does not support format directives that access arguments in an arbitrary order, such as "%2$s", on some platforms: NetBSD 3.0, mingw, MSVC 14.
  • This function doesn’t support the ' flag on some platforms: NetBSD 3.0, Cygwin 1.5.24, mingw, MSVC 14.
  • This function does not round the argument of the ‘a’ directive correctly on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4.
  • printf "%010f" of NaN and Infinity yields an incorrect result (padded with zeroes, or wrong capitalization) on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, AIX 7.3, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC/clang.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • This function does not support precisions larger than 512 or 1024 in integer, floating-point and pointer output on some platforms: AIX 7.1, Solaris 10/x86, mingw, MSVC/clang.
  • This function mishandles large floating point precisions (for example, formatting 1.0 with ‘"%.511f"’) on some platforms: Solaris 10.
  • This function produces wrong output for the ‘lc’ directive with a NUL wide character argument on some platforms: musl libc 1.2.4.
  • This function can crash in out-of-memory conditions on some platforms: FreeBSD 14.0, NetBSD 5.0.
  • The compiler warns that this function is deprecated: macOS 14.

Portability problems fixed by Gnulib module sprintf-gnu:

  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.

Portability problems fixed by either Gnulib module sprintf-posix or sprintf-gnu and additionally the Gnulib module printf-with-n-directive:

  • This function does not support the ‘n’ directive on some platforms: glibc when used with _FORTIFY_SOURCE >= 2 (set by default on Ubuntu), macOS 14, OpenBSD, MSVC 14, Android.

Portability problems not fixed by Gnulib:

  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.
  • Formatting noncanonical ‘long double’ numbers produces nonmeaningful results on some platforms: glibc and others, on x86, x86_64, IA-64 CPUs.
  • When formatting an integer with grouping flag, this function inserts thousands separators even in the "C" locale on some platforms: NetBSD 5.1.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.56 sscanf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sscanf.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-sscanf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.38, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.2, AIX 7.2, HP-UX 11, Solaris 11.4, Cygwin 2.9.0, mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • On Windows, this function doesn’t support the hh, ll, j, t, z size specifiers.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.57 stderr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/stderr.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • stderr is created in 32-bit mode instead of 64-bit mode: Cygwin 1.5.x. One workaround is to use freopen(NULL, "r+", stderr) on Cygwin 1.5.21 or newer. Another is to use the gnulib ftello module and do ftello(stderr).
  • POSIX states that a setuid application can guarantee that fd 2 is open, but some systems guarantee this even for non-setuid programs. If an application is executed with fd 2 closed, use of stderr can affect an unrelated file that happened to be assigned to fd 2. The gnulib xstdopen or the *-safer modules may be used to guarantee that fd 2 stays reserved for stderr.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.58 stdin

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/stdin.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • stdin is created in 32-bit mode instead of 64-bit mode: Cygwin 1.5.x. One workaround is to use freopen(NULL, “r”, stdin) on Cygwin 1.5.21 or newer. Another is to use the gnulib ftello module and do ftello(stdin).
  • POSIX states that a setuid application can guarantee that fd 0 is open, but some systems guarantee this even for non-setuid programs. If an application is executed with fd 0 closed, use of stdin can affect an unrelated file that happened to be assigned to fd 0. The gnulib xstdopen or the *-safer modules may be used to guarantee that fd 0 stays reserved for stdin.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.59 stdout

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/stdout.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • stdout is created in 32-bit mode instead of 64-bit mode: Cygwin 1.5.x. One workaround is to use freopen(NULL, "w", stdout) on Cygwin 1.5.21 or newer. Another is to use the gnulib ftello module and do ftello(stdout).
  • POSIX states that a setuid application can guarantee that fd 1 is open, but some systems guarantee this even for non-setuid programs. If an application is executed with fd 1 closed, use of stdout can affect an unrelated file that happened to be assigned to fd 1. The gnulib xstdopen or the *-safer modules may be used to guarantee that fd 1 stays reserved for stdout.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.60 tmpfile

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tmpfile.html

Gnulib module: tmpfile

Portability problems fixed by Gnulib:

  • This function always fails on some platforms: Android 4.3.
  • This function often fails for trivial reasons on some platforms: mingw, MSVC 14.
  • On platforms where off_t is a 32-bit type, tmpfile may not work correctly to create files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.61 tmpnam

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tmpnam.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is not appropriate for creating temporary files. (It has security risks.) Better use mkstemp instead.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.62 ungetc

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ungetc.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.63 vasprintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/vasprintf.html

Documentation:

Gnulib module: vasprintf or vasprintf-posix or vasprintf-gnu

Portability problems fixed by either Gnulib module vasprintf or vasprintf-posix or vasprintf-gnu:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 10, mingw, MSVC 14.

Portability problems fixed by either Gnulib module vasprintf-posix or vasprintf-gnu:

  • This function does not support size specifiers as in C99 (hh, ll, j, t, z) on some platforms: Cygwin 1.5.24.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • printf "%f", "%e", "%g" of Infinity and NaN yields an incorrect result on some platforms: AIX 7.3, Solaris 11.4.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not support the ‘a’ and ‘A’ directives on some platforms: FreeBSD 5.2.1, OpenBSD 4.0, Solaris 11.4, Cygwin 1.5.x.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support the ‘F’ directive on some platforms: NetBSD 3.0, Cygwin 1.5.x.
  • This function does not support the ‘ls’ directive on some platforms: OpenBSD 4.0, Cygwin 1.5.x, Haiku.
  • This function does not support precisions in the ‘ls’ directive correctly on some platforms: Solaris 11.4.
  • This function does not support format directives that access arguments in an arbitrary order, such as "%2$s", on some platforms: NetBSD 3.0.
  • This function doesn’t support the ' flag on some platforms: NetBSD 3.0, Cygwin 1.5.24.
  • This function does not round the argument of the ‘a’ directive correctly on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4.
  • printf "%010f" of NaN and Infinity yields an incorrect result (padded with zeroes) on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, AIX 7.3, Solaris 11.4, Cygwin 1.5.x.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • This function produces wrong output for the ‘lc’ directive with a NUL wide character argument on some platforms: musl libc 1.2.4.
  • This function can crash in out-of-memory conditions on some platforms: FreeBSD 14.0, NetBSD 5.0.

Portability problems fixed by Gnulib module vasprintf-gnu:

  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.

Portability problems not fixed by Gnulib:

  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.64 vdprintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/vdprintf.html

Gnulib module: vdprintf or vdprintf-posix or vdprintf-gnu

Portability problems fixed by either Gnulib module vdprintf or vdprintf-posix or vdprintf-gnu:

  • This function is missing on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.5.x, mingw, MSVC 14.

Portability problems fixed by either Gnulib module vdprintf-posix or vdprintf-gnu:

  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • printf "%f", "%e", "%g" of Infinity and NaN yields an incorrect result on some platforms: AIX 7.3, Solaris 11.4.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not support the ‘a’ and ‘A’ directives on some platforms: Solaris 11.4.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support precisions in the ‘ls’ directive correctly on some platforms: Solaris 11.4.
  • This function does not round the argument of the ‘a’ directive correctly on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4.
  • printf "%010f" of NaN and Infinity yields an incorrect result (padded with zeroes, or wrong capitalization) on some platforms: AIX 7.3, Solaris 11.4.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • This function does not support precisions larger than 512 or 1024 in integer, floating-point and pointer output on some platforms: AIX 7.1.
  • This function produces wrong output for the ‘lc’ directive with a NUL wide character argument on some platforms: musl libc 1.2.4.

Portability problems fixed by Gnulib module vdprintf-gnu:

  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.

Portability problems fixed by either Gnulib module vdprintf-posix or vdprintf-gnu and additionally the Gnulib module printf-with-n-directive:

  • This function does not support the ‘n’ directive on some platforms: glibc when used with _FORTIFY_SOURCE >= 2 (set by default on Ubuntu), macOS 14, OpenBSD, Android.

Portability problems not fixed by Gnulib:

  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.
  • Formatting noncanonical ‘long double’ numbers produces nonmeaningful results on some platforms: glibc and others, on x86, x86_64, IA-64 CPUs.
  • When formatting an integer with grouping flag, this function inserts thousands separators even in the "C" locale on some platforms: NetBSD 5.1.
  • On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.65 vfprintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/vfprintf.html

Gnulib module: vfprintf-posix or vfprintf-gnu or stdio-h, nonblocking, sigpipe

Portability problems fixed by either Gnulib module stdio-h or fprintf-posix or fprintf-gnu:

  • This function does not support non-ASCII characters in double-byte encoding, corresponding to the locale, on some platforms: mingw with __USE_MINGW_ANSI_STDIO in combination with msvcrt, when the output goes to a Windows console.

Portability problems fixed by either Gnulib module vfprintf-posix or vfprintf-gnu:

  • This function does not support size specifiers as in C99 (hh, ll, j, t, z) on some platforms: AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.24, old mingw, MSVC 9.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • printf of ‘long double’ numbers is unsupported on some platforms: mingw, MSVC 14.
  • printf "%f", "%e", "%g" of Infinity and NaN yields an incorrect result on some platforms: AIX 7.3, Solaris 11.4, mingw, MSVC 14.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not support the ‘a’ and ‘A’ directives on some platforms: FreeBSD 5.2.1, OpenBSD 4.0, AIX 5.2, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support the ‘F’ directive on some platforms: NetBSD 3.0, AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘ls’ directive on some platforms: OpenBSD 4.0, Cygwin 1.5.x, Haiku.
  • This function does not support precisions in the ‘ls’ directive correctly on some platforms: Solaris 11.4.
  • This function does not support format directives that access arguments in an arbitrary order, such as "%2$s", on some platforms: NetBSD 3.0, mingw, MSVC 14.
  • This function doesn’t support the ' flag on some platforms: NetBSD 3.0, Cygwin 1.5.24, mingw, MSVC 14.
  • This function does not round the argument of the ‘a’ directive correctly on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4.
  • printf "%010f" of NaN and Infinity yields an incorrect result (padded with zeroes, or wrong capitalization) on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, AIX 7.3, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC/clang.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • This function does not support precisions larger than 512 or 1024 in integer, floating-point and pointer output on some platforms: AIX 7.1, Solaris 10/x86, mingw, MSVC/clang.
  • This function mishandles large floating point precisions (for example, formatting 1.0 with ‘"%.511f"’) on some platforms: Solaris 10.
  • This function produces wrong output for the ‘lc’ directive with a NUL wide character argument on some platforms: musl libc 1.2.4.
  • This function can crash in out-of-memory conditions on some platforms: FreeBSD 14.0, NetBSD 5.0.

Portability problems fixed by Gnulib module vfprintf-gnu:

  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.

Portability problems fixed by either Gnulib module vfprintf-posix or vfprintf-gnu and additionally the Gnulib module printf-with-n-directive:

  • This function does not support the ‘n’ directive on some platforms: glibc when used with _FORTIFY_SOURCE >= 2 (set by default on Ubuntu), macOS 14, OpenBSD, MSVC 14, Android.

Portability problems fixed by Gnulib module stdio-h or vfprintf-posix or vfprintf-gnu, together with module nonblocking:

  • When writing to a non-blocking pipe whose buffer is full, this function fails with errno being set to ENOSPC instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems fixed by Gnulib module stdio-h or vfprintf-posix or vfprintf-gnu, together with module sigpipe:

  • When writing to a pipe with no readers, this function fails, instead of obeying the current SIGPIPE handler, on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.
  • Formatting noncanonical ‘long double’ numbers produces nonmeaningful results on some platforms: glibc and others, on x86, x86_64, IA-64 CPUs.
  • When formatting an integer with grouping flag, this function inserts thousands separators even in the "C" locale on some platforms: NetBSD 5.1.
  • Attempting to write to a read-only stream fails with EOF but does not set the error flag for ferror on some platforms: glibc 2.13, cygwin 1.7.9.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.66 vfscanf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/vfscanf.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-vfscanf.html

Gnulib module: vfscanf, nonblocking

Portability problems fixed by Gnulib module vfscanf, together with module nonblocking:

  • When reading from a non-blocking pipe whose buffer is empty, this function fails with errno being set to EINVAL instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.38, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.2, AIX 7.2, HP-UX 11, Solaris 11.4, Cygwin 2.9.0, mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • On Windows, this function doesn’t support the hh, ll, j, t, z size specifiers.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.67 vprintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/vprintf.html

Gnulib module: vprintf-posix or vprintf-gnu or stdio-h, nonblocking, sigpipe

Portability problems fixed by either Gnulib module stdio-h or fprintf-posix or fprintf-gnu:

  • This function does not support non-ASCII characters in double-byte encoding, corresponding to the locale, on some platforms: mingw with __USE_MINGW_ANSI_STDIO in combination with msvcrt, when the output goes to a Windows console.

Portability problems fixed by either Gnulib module vprintf-posix or vprintf-gnu:

  • This function does not support size specifiers as in C99 (hh, ll, j, t, z) on some platforms: AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.24, old mingw, MSVC 9.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • printf of ‘long double’ numbers is unsupported on some platforms: mingw, MSVC 14.
  • printf "%f", "%e", "%g" of Infinity and NaN yields an incorrect result on some platforms: AIX 7.3, Solaris 11.4, mingw, MSVC 14.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not support the ‘a’ and ‘A’ directives on some platforms: FreeBSD 5.2.1, OpenBSD 4.0, AIX 5.2, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support the ‘F’ directive on some platforms: NetBSD 3.0, AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘ls’ directive on some platforms: OpenBSD 4.0, Cygwin 1.5.x, Haiku.
  • This function does not support precisions in the ‘ls’ directive correctly on some platforms: Solaris 11.4.
  • This function does not support format directives that access arguments in an arbitrary order, such as "%2$s", on some platforms: NetBSD 3.0, mingw, MSVC 14.
  • This function doesn’t support the ' flag on some platforms: NetBSD 3.0, Cygwin 1.5.24, mingw, MSVC 14.
  • This function does not round the argument of the ‘a’ directive correctly on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4.
  • printf "%010f" of NaN and Infinity yields an incorrect result (padded with zeroes, or wrong capitalization) on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, AIX 7.3, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC/clang.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • This function does not support precisions larger than 512 or 1024 in integer, floating-point and pointer output on some platforms: AIX 7.1, Solaris 10/x86, mingw, MSVC/clang.
  • This function mishandles large floating point precisions (for example, formatting 1.0 with ‘"%.511f"’) on some platforms: Solaris 10.
  • This function produces wrong output for the ‘lc’ directive with a NUL wide character argument on some platforms: musl libc 1.2.4.
  • This function can crash in out-of-memory conditions on some platforms: FreeBSD 14.0, NetBSD 5.0.

Portability problems fixed by Gnulib module vprintf-gnu:

  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.

Portability problems fixed by either Gnulib module vprintf-posix or vprintf-gnu and additionally the Gnulib module printf-with-n-directive:

  • This function does not support the ‘n’ directive on some platforms: glibc when used with _FORTIFY_SOURCE >= 2 (set by default on Ubuntu), macOS 14, OpenBSD, MSVC 14, Android.

Portability problems fixed by Gnulib module stdio-h or vprintf-posix or vprintf-gnu, together with module nonblocking:

  • When writing to a non-blocking pipe whose buffer is full, this function fails with errno being set to ENOSPC instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems fixed by Gnulib module stdio-h or vprintf-posix or vprintf-gnu, together with module sigpipe:

  • When writing to a pipe with no readers, this function fails, instead of obeying the current SIGPIPE handler, on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.
  • Formatting noncanonical ‘long double’ numbers produces nonmeaningful results on some platforms: glibc and others, on x86, x86_64, IA-64 CPUs.
  • When formatting an integer with grouping flag, this function inserts thousands separators even in the "C" locale on some platforms: NetBSD 5.1.
  • Attempting to write to a read-only stream fails with EOF but does not set the error flag for ferror on some platforms: glibc 2.13, cygwin 1.7.9.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.68 vscanf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/vscanf.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-vscanf.html

Gnulib module: vscanf, nonblocking

Portability problems fixed by Gnulib module vscanf, together with module nonblocking:

  • When reading from a non-blocking pipe whose buffer is empty, this function fails with errno being set to EINVAL instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.38, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.2, AIX 7.2, HP-UX 11, Solaris 11.4, Cygwin 2.9.0, mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • On Windows, these functions don’t support the hh, ll, j, t, z size specifiers.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.69 vsnprintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/vsnprintf.html

Gnulib module: vsnprintf or vsnprintf-posix or vsnprintf-gnu

Portability problems fixed by either Gnulib module vsnprintf or vsnprintf-posix or vsnprintf-gnu:

  • This function does not support format directives that access arguments in an arbitrary order, such as "%2$s", on some platforms: NetBSD 3.0, mingw, MSVC 14.
  • This function does not return a byte count as specified in C99 on some platforms: HP-UX 11, Solaris 9, mingw, MSVC 14.

Portability problems fixed by either Gnulib module vsnprintf-posix or vsnprintf-gnu:

  • This function does not support size specifiers as in C99 (hh, ll, j, t, z) on some platforms: AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.24, old mingw, MSVC 9.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • printf of ‘long double’ numbers is unsupported on some platforms: mingw, MSVC 14.
  • printf "%f", "%e", "%g" of Infinity and NaN yields an incorrect result on some platforms: AIX 7.3, Solaris 11.4, mingw, MSVC 14.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not support the ‘a’ and ‘A’ directives on some platforms: FreeBSD 5.2.1, OpenBSD 4.0, AIX 5.2, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support the ‘F’ directive on some platforms: NetBSD 3.0, AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘ls’ directive on some platforms: OpenBSD 4.0, Cygwin 1.5.x, Haiku.
  • This function does not support precisions in the ‘ls’ directive correctly on some platforms: Solaris 11.4.
  • This function doesn’t support the ' flag on some platforms: NetBSD 3.0, Cygwin 1.5.24, mingw, MSVC 14.
  • This function does not round the argument of the ‘a’ directive correctly on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4.
  • printf "%010f" of NaN and Infinity yields an incorrect result (padded with zeroes, or wrong capitalization) on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, AIX 7.3, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC/clang.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • This function does not support precisions larger than 512 or 1024 in integer, floating-point and pointer output on some platforms: AIX 7.1, Solaris 10/x86, mingw, MSVC/clang.
  • This function mishandles large floating point precisions (for example, formatting 1.0 with ‘"%.511f"’) on some platforms: Solaris 10.
  • This function produces wrong output for the ‘lc’ directive with a NUL wide character argument on some platforms: musl libc 1.2.4.
  • This function can crash in out-of-memory conditions on some platforms: FreeBSD 14.0, NetBSD 5.0.
  • This function does not truncate the result as specified in C99 on some platforms: mingw, MSVC 14.
  • This function overwrites memory even when a zero size argument is passed on some platforms: HP-UX 11.

Portability problems fixed by Gnulib module vsnprintf-gnu:

  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.

Portability problems fixed by either Gnulib module vsnprintf-posix or vsnprintf-gnu and additionally the Gnulib module printf-with-n-directive:

  • This function does not fully support the ‘n’ directive on some platforms: glibc when used with _FORTIFY_SOURCE >= 2 (set by default on Ubuntu), macOS 14, OpenBSD, HP-UX 11, mingw, MSVC 14, Android.

Portability problems not fixed by Gnulib:

  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.
  • Formatting noncanonical ‘long double’ numbers produces nonmeaningful results on some platforms: glibc and others, on x86, x86_64, IA-64 CPUs.
  • When formatting an integer with grouping flag, this function inserts thousands separators even in the "C" locale on some platforms: NetBSD 5.1.

Next: , Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.70 vsprintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/vsprintf.html

Gnulib module: vsprintf-posix or vsprintf-gnu

Portability problems fixed by either Gnulib module vsprintf-posix or vsprintf-gnu:

  • This function does not support size specifiers as in C99 (hh, ll, j, t, z) on some platforms: AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.24, old mingw, MSVC 9.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • printf of ‘long double’ numbers is unsupported on some platforms: mingw, MSVC 14.
  • printf "%f", "%e", "%g" of Infinity and NaN yields an incorrect result on some platforms: AIX 7.3, Solaris 11.4, mingw, MSVC 14.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not support the ‘a’ and ‘A’ directives on some platforms: FreeBSD 5.2.1, OpenBSD 4.0, AIX 5.2, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support the ‘F’ directive on some platforms: NetBSD 3.0, AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘ls’ directive on some platforms: OpenBSD 4.0, Cygwin 1.5.x, Haiku.
  • This function does not support precisions in the ‘ls’ directive correctly on some platforms: Solaris 11.4.
  • This function does not support format directives that access arguments in an arbitrary order, such as "%2$s", on some platforms: NetBSD 3.0, mingw, MSVC 14.
  • This function doesn’t support the ' flag on some platforms: NetBSD 3.0, Cygwin 1.5.24, mingw, MSVC 14.
  • This function does not round the argument of the ‘a’ directive correctly on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4.
  • printf "%010f" of NaN and Infinity yields an incorrect result (padded with zeroes, or wrong capitalization) on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, AIX 7.3, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC/clang.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • This function does not support precisions larger than 512 or 1024 in integer, floating-point and pointer output on some platforms: AIX 7.1, Solaris 10/x86, mingw, MSVC/clang.
  • This function mishandles large floating point precisions (for example, formatting 1.0 with ‘"%.511f"’) on some platforms: Solaris 10.
  • This function produces wrong output for the ‘lc’ directive with a NUL wide character argument on some platforms: musl libc 1.2.4.
  • This function can crash in out-of-memory conditions on some platforms: FreeBSD 14.0, NetBSD 5.0.
  • The compiler warns that this function is deprecated: macOS 14.

Portability problems fixed by Gnulib module vsprintf-gnu:

  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.

Portability problems fixed by either Gnulib module vsprintf-posix or vsprintf-gnu and additionally the Gnulib module printf-with-n-directive:

  • This function does not support the ‘n’ directive on some platforms: glibc when used with _FORTIFY_SOURCE >= 2 (set by default on Ubuntu), macOS 14, OpenBSD, MSVC 14, Android.

Portability problems not fixed by Gnulib:

  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.
  • Formatting noncanonical ‘long double’ numbers produces nonmeaningful results on some platforms: glibc and others, on x86, x86_64, IA-64 CPUs.
  • When formatting an integer with grouping flag, this function inserts thousands separators even in the "C" locale on some platforms: NetBSD 5.1.

Previous: , Up: Functions in <stdio.h>   [Contents][Index]

10.45.71 vsscanf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/vsscanf.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-vsscanf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: MSVC 14.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.38, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.2, AIX 7.2, HP-UX 11, Solaris 11.4, Cygwin 2.9.0, mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.
  • On Windows, these functions don’t support the hh, ll, j, t, z size specifiers.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.46 Functions in <stdlib.h>

Next: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.1 _Exit

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/_Exit.html

Gnulib module: _Exit

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.5.x, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.2 a64l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/a64l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, Minix 3.1.8, mingw, MSVC 14, Android 9.0.
  • This function was not correctly implemented in glibc versions before 2.2.5.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.3 abort

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/abort.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • Some platforms mistakenly close all stdio streams prior to raising SIGABRT: Cygwin 1.5.x.
  • Some platforms always print a message to stderr, even if a SIGABRT handler uses longjmp to resume execution at a safe point: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.4 abs

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/abs.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Android 4.3.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.5 aligned_alloc

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.24.3.1.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/aligned_alloc.html

Documentation:
man aligned_alloc

Gnulib module: aligned_alloc

Portability problems fixed by Gnulib:

  • This function fails if the alignment argument is smaller than sizeof (void *) on some platforms: macOS 14, AIX 7.3.1.
  • This function returns a null pointer if the requested size is not a multiple of the alignment: Solaris 11.4.
  • This function returns a null pointer if the size argument is zero: macOS 15, AIX 7.3, Solaris 11.4.
  • On some platforms, aligned_alloc crashes if the requested size is not a multiple of the alignment: AddressSanitizer (gcc 11.2 or clang 13).

Portability problems not fixed by Gnulib:

  • This function is missing on many older platforms: glibc 2.15, macOS 10.14, FreeBSD 6.4, NetBSD 7.1, OpenBSD 6.0, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.
  • If the alignment and size are absurdly large, this function crashes: glibc 2.42.

Gnulib has partial substitutes for aligned_alloc that do not crash even if the AddressSanitizer bug is present:

  • The Gnulib module alignalloc provides a portable function alignalloc that is a near-substitute for glibc aligned_alloc, except that the result must be freed with alignfree rather than plain free.
  • The Gnulib module aligned-malloc provides functions for allocating and freeing blocks of suitably aligned memory.
  • The Gnulib module pagealign_alloc provides a similar API for allocating and freeing blocks of memory aligned on a system page boundary.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.6 at_quick_exit

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.24.4.3.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/at_quick_exit.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.9, macOS 14, FreeBSD 6.4, NetBSD 5.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.3.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.7 atexit

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atexit.html

Gnulib module: atexit

Portability problems fixed by Gnulib:

  • This function is missing on some old platforms.

Portability problems not fixed by Gnulib:

  • The exit status can be incorrect for a process terminated by a signal during a call to a function registered by atexit. This is because if a signal terminates a process after exit is called or main returns, the process’s exit status is that specified by exit’s argument or by main’s return value, instead of being the exit status corresponding to the signal: z/OS 3.1.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.8 atof

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atof.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Android 4.4.
  • This function mis-parses strings with leading ‘+’ on some old platforms: Old versions of Linux.
  • This function returns a positive value for negative underflow on some platforms: glibc 2.4, Mingw, Cygwin.
  • This function fails to do a valid parse of ‘-0x’ on some platforms: glibc 2.4, Cygwin < 1.5.25-11.
  • This function fails to parse Infinities and plain NaNs on some platforms: Mingw, OpenBSD 4.0.
  • This function fails to parse NaN() on some platforms: Mingw, OpenBSD 4.0, Cygwin < 1.5.25-11.
  • This function fails to parse NaN(n-char-sequence) on some platforms: Mingw, OpenBSD 4.0.
  • This function fails to parse C99 hexadecimal floating point on some platforms: Mingw, OpenBSD 4.0.
  • This function fails to correctly parse very long strings on some platforms: Mingw, Cygwin.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.9 atoi

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atoi.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.10 atol

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atol.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.11 atoll

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/atoll.html

Gnulib module: atoll

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11.23, MSVC 9.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.12 bsearch

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/bsearch.html

Gnulib module: bsearch

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.13 calloc

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/calloc.html

Gnulib module: calloc-posix

Portability problems fixed by Gnulib:

  • On some platforms, when the function fails it does not set errno: mingw, MSVC 14.
  • On some platforms, when the function fails it might set errno to EAGAIN instead of to ENOMEM. Although POSIX allows EAGAIN, the calloc-posix module insists on ENOMEM which also conforms to POSIX and is GNU-compatible: Solaris 11.4.
  • On some platforms, calloc (n, s) can succeed even if multiplying n by s would exceed PTRDIFF_MAX or SIZE_MAX. Although failing to check for exceeding PTRDIFF_MAX is arguably allowed by POSIX it can lead to undefined behavior later, so calloc-posix does not allow going over the limit.

Extension: Gnulib provides a module ‘calloc-gnu’ that substitutes a calloc implementation that behaves more like the glibc implementation. It fixes this portability problem:

  • calloc (0, s) and calloc (n, 0) return NULL on success on some platforms: AIX 7.3.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.14 div

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/div.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.15 drand48

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/drand48.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.16 erand48

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/erand48.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.17 exit

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/exit.html

Gnulib module: stdlib-h

Portability problems fixed by Gnulib:

  • Some problems with the macros EXIT_SUCCESS and EXIT_FAILURE, see stdlib.h.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.18 free

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/free.html

Gnulib module: free-posix

Portability problems fixed by Gnulib:

  • This function may clobber errno on many platforms: glibc 2.32, Mac OS X, FreeBSD, NetBSD, OpenBSD 4.4, Minix, AIX, HP-UX, Cygwin, mingw, MSVC.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.19 free_aligned_sized

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.24.3.5

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on most non-C23 platforms: glibc 2.42, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.20 free_sized

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.24.3.4

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on most non-C23 platforms: glibc 2.42, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.21 getenv

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getenv.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.22 getsubopt

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getsubopt.html

Gnulib module: getsubopt

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 7.1.
  • This function is declared in unistd.h instead of stdlib.h on some platforms: Cygwin 1.7.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.23 grantpt

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/grantpt.html

Gnulib module: grantpt

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

  • This function reports success for invalid file descriptors on some platforms: OpenBSD, Cygwin 1.7.9, musl libc.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.24 initstate

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/initstate.html

Gnulib module: random

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4.
  • This function is not declared on some platforms: Cygwin 1.5.25.

Portability problems not fixed by Gnulib:

  • This function crashes if the state buffer is unaligned on some platforms: glibc 2.40/sparc.
  • The first parameter is unsigned long instead of unsigned int on some platforms: MidnightBSD 2.0.
  • The third parameter is long instead of size_t on some platforms: MidnightBSD 2.0.
  • This function makes out-of-bounds writes on some platforms: Haiku.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.25 jrand48

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/jrand48.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.26 l64a

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/l64a.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, Minix 3.1.8, mingw, MSVC 14, Android 9.0.
  • This function was not correctly implemented in glibc versions before 2.2.5.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.27 labs

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/labs.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Android 4.3.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.28 lcong48

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lcong48.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 5.1.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.29 ldiv

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ldiv.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.30 llabs

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/llabs.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.23, MSVC 9, Android 4.3.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.31 lldiv

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lldiv.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, HP-UX 11.23, MSVC 9.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.32 lrand48

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lrand48.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.33 malloc

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/malloc.html

Gnulib module: malloc-posix

Portability problems fixed by Gnulib:

  • On some platforms, when the function fails it does not set errno: mingw, MSVC 14.
  • On some platforms, when the function fails it might set errno to EAGAIN instead of to ENOMEM. Although POSIX allows EAGAIN, the malloc-posix module insists on ENOMEM which also conforms to POSIX and is GNU-compatible: Solaris 11.4.
  • On some platforms, malloc (n) can succeed even if n exceeds PTRDIFF_MAX. Although this behavior is arguably allowed by POSIX it can lead to behavior not defined by POSIX later, so malloc-posix does not allow going over the limit.

Extension: Gnulib provides a module ‘malloc-gnu’ that substitutes a malloc implementation that behaves more like the glibc implementation, by fixing this portability problem:

  • malloc (0) returns NULL on success on some platforms: AIX 7.3.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.34 mblen

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mblen.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Android 7.1.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.35 mbstowcs

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mbstowcs.html

Gnulib module: mbstowcs

Portability problems fixed by Gnulib:

  • In the C or POSIX locales, this function can return (size_t) -1 and set errno to EILSEQ: glibc 2.35.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function mbstoc32s, provided by Gnulib module mbstoc32s, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.36 mbtowc

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mbtowc.html

Gnulib module: mbtowc

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Android 4.4.

Portability problems not fixed by Gnulib:

  • In UTF-8 locales, this function may return wide characters up to 0x7FFFFFFF (that is, beyond 0x0010FFFF) on some platforms: glibc 2.34.
  • This function accumulates hidden state on some platforms: glibc 2.8 (see https://sourceware.org/PR9674).
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.37 memalignment

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.24.9.1

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on most non-C23 platforms: glibc 2.42, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.

To check whether a pointer P has alignment A, Gnulib code typically tests (uintptr_t) P % A instead of memalignment (P) % A. See Other portability assumptions made by Gnulib.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.38 mkdtemp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mkdtemp.html

Gnulib module: mkdtemp

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 10, mingw, MSVC 14.
  • This function is declared in <unistd.h> instead of <stdlib.h> on some platforms: macOS 26.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.39 mkostemp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mkostemp.html

Documentation:
man mkostemp

Gnulib module: mkostemp

Portability problems fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.6, Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.5, mingw, MSVC 14, Android 5.1.
  • This function is declared in <unistd.h> instead of <stdlib.h> on some platforms: macOS 14.
  • On platforms where off_t is a 32-bit type, mkostemp may not work correctly to create files larger than 2 GB. (Cf. AC_SYS_LARGEFILE.)

Portability problems not fixed by Gnulib:

The gnulib module clean-temp can create temporary files that will not be left behind after signals such as SIGINT.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.40 mkstemp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mkstemp.html

Gnulib module: mkstemp

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • On platforms where off_t is a 32-bit type, mkstemp may not work correctly to create files 2 GiB and larger. See Large File Support.
  • On some older platforms, mkstemp can create a world or group writable or readable file, if you haven’t set the process umask to 077. This is a security risk.

Portability problems not fixed by Gnulib:

The gnulib module clean-temp can create temporary files that will not be left behind after signals such as SIGINT.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.41 mrand48

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mrand48.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.42 nrand48

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/nrand48.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.43 posix_memalign

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_memalign.html

Gnulib module: posix_memalign

Although this function is superseded by aligned_alloc, it is more portable to older systems that do not support C11. See aligned_alloc.

Portability problems fixed by Gnulib:

  • This function returns a null pointer if the size argument is zero: AIX 7.3.
  • This function produces misaligned results on some platforms: OpenBSD 6.1.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 4.1.
  • If the alignment and size are absurdly large, this function crashes: glibc 2.42.

The Gnulib module aligned-malloc provides functions for allocating and freeing blocks of suitably aligned memory.

The Gnulib module pagealign_alloc provides a similar API for allocating and freeing blocks of memory aligned on a system page boundary.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.44 posix_openpt

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_openpt.html

Gnulib module: posix_openpt

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.x, mingw, MSVC 14, Android 4.4. However, the replacement may fail with ENOSYS or ENOENT on some platforms.

Portability problems not fixed by Gnulib:

Note that when using this function to open the master side of a pseudo-terminal, you still need platform dependent code to open the corresponding slave side. The Gnulib module openpty provides an easy-to-use API that does both at once.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.45 ptsname

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ptsname.html

Gnulib module: ptsname

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, mingw, MSVC 14.
  • This function fails to set errno on failure on some platforms: FreeBSD 8.2.

Portability problems not fixed by Gnulib:

  • On Solaris 11 2010-11, this function fails on all BSD-style /dev/pty* device files.
  • This function is not thread-safe on some platforms: Cygwin 1.7.9. Likewise, the gnulib replacement is not thread-safe.

Note that the Gnulib module ptsname_r is a version of this function that is more likely to be thread-safe.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.46 ptsname_r

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ptsname_r.html

Documentation:

Gnulib module: ptsname_r

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.12, FreeBSD 12.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.9, mingw, MSVC 14.
  • When this function fails, it returns -1 instead of the error code on some platforms: macOS 14, FreeBSD 14.0, Android 4.3.
  • When this function fails with ERANGE, it stores an empty string as result on some platforms: NetBSD 10.0, Solaris 11 OmniOS.

Portability problems not fixed by Gnulib:

  • When this function fails, it returns 0 and stores an empty string as result on some platforms: Cygwin 2.9.

Note: Portable programs should expect to find the error code as the return value of this function, not as the value of errno. This is needed for compatibility with musl libc and with the forthcoming POSIX Issue 8.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.47 putenv

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/putenv.html, amended through https://www.austingroupbugs.net/view.php?id=1598.

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Environment-Access.html.

Note: POSIX putenv supports adding or changing the value of an environment variable, while glibc also supports removing an environment variable (as if by unsetenv).

Gnulib module: putenv-gnu

Portability problems fixed by Gnulib:

  • This function does not support removing an environment variable on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, mingw, MSVC 14, Android 11.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.48 qsort

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/qsort.html

Gnulib module: qsort

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.49 qsort_r

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/qsort_r.html

Documentation:
man qsort_r

Gnulib module: qsort_r

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.7, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android API level 35.
  • This function has an incompatible API on some platforms: FreeBSD 13.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.50 quick_exit

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.24.4.7.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/quick_exit.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.9, macOS 14, FreeBSD 6.4, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 9, Android 4.4.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.51 rand

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/rand.html

Gnulib module: rand

Portability problems fixed by Gnulib:

  • This function crashes when used in multithreaded processes on some platforms: CheriBSD.

Portability problems not fixed by Gnulib:

  • This function is only defined as an inline function on some platforms: Android 4.4.
  • This function is not thread-safe on some platforms: musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, AIX 7.1, Solaris 11.4.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.52 rand_r

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/rand_r.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 4.4.
  • This function is removed in POSIX.1-2024. Use the function random_r from Gnulib module random_r instead.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.53 random

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/random.html

Gnulib module: random

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • This function is only defined as an inline function on some platforms: Android 4.4.
  • This function is not thread-safe on some platforms: macOS 14, FreeBSD 13.2, Solaris 11.4, Cygwin 3.4.6, Haiku.

Portability problems not fixed by Gnulib:

  • This function has a slightly incompatible declaration (the return type being ‘int’ instead of ‘long’) on some platforms: Cygwin 1.5.25, Haiku.
  • When ‘srandom’ was not called, this function returns a non-deterministic sequence rather than a deterministic sequence of numbers on some platforms: OpenBSD 7.4.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.54 realloc

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/realloc.html

Gnulib module: realloc-posix

Portability problems fixed by Gnulib:

  • On some platforms, when the function fails it does not set errno: FreeBSD 15 (for a size > 0x7000000000000000), mingw, MSVC 14.
  • On some platforms, when the function fails it might set errno to EAGAIN instead of to ENOMEM. Although POSIX allows EAGAIN, the realloc-posix module insists on ENOMEM which also conforms to POSIX and is GNU-compatible: Solaris 11.4.
  • On some platforms, realloc (p, n) can succeed even if n exceeds PTRDIFF_MAX. Although this behavior is arguably allowed by POSIX it is not compatible with GNU and can lead to behavior not defined by POSIX later, so realloc-posix does not allow going over the limit.
  • It is not portable to call realloc with a size of 0.

    With a null pointer argument, this is the same ambiguity as malloc (0) as to whether a successful call returns a null pointer or a pointer to a new zero-sized memory region. Although both behaviors conform to POSIX, realloc-posix insists on the latter behavior, which is compatible with GNU.

    With non-null p, behavior is a real mess for realloc (p, 0). C23 says behavior is undefined. C89 through C17 say a successful call returns either a null pointer or a pointer to a new zero-sized memory region. POSIX.1-2017 extends C99 by saying that if a successful call returns a null pointer it must also set errno to an implementation-defined value, and POSIX.1-2024 extends C17 a bit further by saying that such a call must set errno to EINVAL. It is not known what POSIX.1-2024’s successor will say, though presumably it will extend C23. In practice, successful realloc (p, 0) calls have one of the following behaviors:

    1. Free p, do not change errno, and return a null pointer: glibc 2.33–2.41 by default, Android.
    2. Free p, possibly set errno, and return a null pointer: glibc 1–2.1 if specially built with REALLOC_ZERO_BYTES_FREES=1, glibc 2.1.1–2.32 by default, mingw, MSVC 14.
    3. Free p, set errno to EINVAL, and return a null pointer: AIX 7.3 without _LINUX_SOURCE_COMPAT.
    4. Free p and return a pointer to a new region of size zero: AIX 7.3 with _LINUX_SOURCE_COMPAT, glibc 1–2.1 by default, glibc 2.1.1–2.41 if specially built with REALLOC_ZERO_BYTES_FREES=0, musl libc, macOS, FreeBSD, NetBSD, OpenBSD, Solaris, Cygwin.

    Behaviors (3) and (4) conform to POSIX; behaviors (1) and (2) do not. The realloc-posix module insists on behavior (4) as it is more popular than (3) and is more useful in practice. Behavior (4) is the only one of the four in which returning a null pointer means failure, which is what non-expert programmers typically expect.

    A program not suspecting these variations in semantics will either:

    • Leak memory (the still-valid p) if it unwisely does not check for realloc failure, when it assumes behavior (1), (2) or (3) but the system implements behavior (4).
    • Falsely respond to memory exhaustion (if it wisely checks for realloc failure), or have double-free bugs (if it unwisely does not check), when it assumes behavior (4) but the system implements (1), (2) or (3).
  • When realloc (p, 0) sets errno to EINVAL and returns null, a POSIX.1-2024 application cannot tell whether the call has succeeded and freed p, or has failed without freeing p. This is only a theoretical problem, though, as the only practical implementation with this behavior is AIX without _LINUX_SOURCE_COMPAT, which behaves this way only when the call succeeds.

Portability problems not fixed by Gnulib:

  • When not growing an already-allocated region, i.e., when p points to a region of size psize and n <= psize, realloc (p, n) can fail and return a null pointer: glibc 2.42 and probably other platforms.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.55 reallocarray

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/reallocarray.html

Documentation:

Gnulib module: reallocarray

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.25, macOS 14, FreeBSD 10, NetBSD 7, OpenBSD 5.5, Minix 3.3.0, AIX 7.2, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.
  • On some platforms, when the function fails it might set errno to EAGAIN instead of to ENOMEM. Although POSIX allows EAGAIN, the reallocarray module insists on ENOMEM which also conforms to POSIX and is GNU-compatible: Solaris 11.4.
  • On some platforms, reallocarray (p, n, s) can succeed even if multiplying n by s would exceed PTRDIFF_MAX, which can lead to undefined behavior later: FreeBSD 13, NetBSD 9, OpenBSD 6, musl 1.2.
  • It is not portable to call reallocarray (p, n, s) when either n or s is zero, as reallocarray has the same issues with zero sizes that realloc does. See realloc.

Portability problems not fixed by Gnulib:

  • When not growing an already-allocated region, reallocarray, like realloc, can fail and return a null pointer: glibc 2.42 and probably other platforms.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.56 realpath

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/realpath.html

Gnulib module: canonicalize-lgpl

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • This function does not allow for a NULL ‘resolved’ parameter on some platforms: Mac OS X 10.5, FreeBSD 6.4, OpenBSD 4.4, Solaris 10.
  • This function does not always return an absolute path on some platforms: Solaris 10.
  • This function fails to detect trailing slashes on non-directories on some platforms: glibc 2.3.5, macOS 14, OpenBSD 6.0.
  • This function fails to recognize non-directories or symlinks to non-directories followed by ‘..’ on some platforms: macOS 14, Cygwin 2.9.
  • This function misbehaves on consecutive slashes on some platforms: musl libc 1.2.2, AIX 7.

Portability problems not fixed by Gnulib:

  • This function does not allow to determine the required size of output buffer; the use of a non-NULL ‘resolved’ buffer is non-portable, since PATH_MAX, if it is defined, is nothing more than a guess.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.57 secure_getenv

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/secure_getenv.html

Documentation:

Gnulib module: secure_getenv

Portability problems fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.16, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 5.2, Minix 3.2.0, AIX 7.1, HP-UX 11, Solaris 11.3, Cygwin 3.0, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.58 seed48

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/seed48.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.59 setenv

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setenv.html

Gnulib module: setenv

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11.23, Solaris 9, mingw, MSVC 14.
  • On some platforms, this function does not fail with EINVAL when passed an empty string or a string containing ‘=’: Mac OS X 10.5, FreeBSD 6.0, NetBSD 1.6, OpenBSD 7.9, Cygwin 1.5.x.
  • On some platforms, this function removes a leading ‘=’ from the value argument: Cygwin 1.5.x.

Portability problems not fixed by Gnulib:

  • Older versions of POSIX required that setenv(NULL,"",0) gracefully fail with EINVAL, but not all implementations guarantee this, and the requirement was removed.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.60 setkey

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setkey.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.34, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function is not declared in <stdlib.h> (without -D_GNU_SOURCE) on some platforms: glibc (at least 2.11–2.13).
  • POSIX.1-2024 says this function is obsolescent and it is planned to be removed in a future version.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.61 setstate

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setstate.html

Gnulib module: random

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4.
  • This function is not declared on some platforms: Cygwin 1.5.25.

Portability problems not fixed by Gnulib:

  • This function has a slightly incompatible declaration (the argument type being ‘const char *’ instead of ‘char *’) on some platforms: macOS 14, AIX 7.1, HP-UX 11.31, Solaris 11.4, Solaris 11 OpenIndiana.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.62 srand

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/srand.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is only defined as an inline function on some platforms: Android 4.4.
  • This function has no effect on rand invocations in other threads on some platforms: Cygwin 3.4.6.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.63 srand48

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/srand48.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.64 srandom

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/srandom.html

Gnulib module: random

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • This function is only defined as an inline function on some platforms: Android 4.4.

Portability problems not fixed by Gnulib:

  • This function has a slightly incompatible declaration (the return type being ‘long’ instead of ‘void’) on some platforms: Cygwin 1.5.25.
  • The parameter is unsigned long instead of unsigned int on some platforms: MidnightBSD 2.0.
  • This function has no effect on some platforms: OpenBSD 7.4. This platform has, instead, a function srandom_deterministic.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.65 strfromd

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.66 strfromf

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.67 strfroml

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.24, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.68 strtod

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strtod.html

Gnulib module: strtod or strtod-obsolete

Portability problems fixed by either Gnulib module strtod or strtod-obsolete:

  • This function mis-parses strings with leading ‘+’ on some old platforms: Old versions of Linux.
  • This function returns a wrong end pointer on some old platforms.
  • This function allows whitespace between ‘e’ and the exponent on some platforms: HP-UX 11.11.
  • This function returns the wrong end pointer for ‘-0x’ on some platforms: glibc 2.4, Mac OS X 10.5, FreeBSD 6.2, AIX 7.1, Cygwin < 1.5.25-11.
  • This function fails to parse Infinities and plain NaNs on some platforms: OpenBSD 4.0, HP-UX 11.11, Solaris 9, mingw, MSVC 14.
  • This function fails to parse ‘NaN()’ on some platforms: glibc 2.3.6, Mac OS X 10.5, FreeBSD 6.2, OpenBSD 4.0, AIX 7.1, HP-UX 11.11, Cygwin < 1.5.25-11, mingw, MSVC 14.
  • This function fails to parse ‘NaN(n-char-sequence)’ on some platforms: OpenBSD 4.0, HP-UX 11.11, mingw, MSVC 14.
  • This function parses ‘NaN(n-char-sequence)’, but returns the wrong end pointer on some platforms: glibc 2.4, AIX 7.1.
  • This function misparses ‘nan(’ on some platforms: macOS 10.6.6.
  • This function returns ‘NaN’ for ‘-NaN’ on some platforms: glibc 2.27, musl libc.
  • This function fails to parse C99 hexadecimal floating point on some platforms: NetBSD 5.0, OpenBSD 4.0, AIX 5.1, HP-UX 11.11, Solaris 11.4, mingw, MSVC 14.
  • In hexadecimal floats, this function allows whitespace between ‘p’ and the exponent on some platforms: HP-UX 11.31/ia64.
  • This function returns the wrong end pointer for ‘0x1p’ on some platforms: AIX 7.1.
  • This function fails to set errno upon gradual underflow (resulting in a denormalized number) on some platforms: Cygwin 2.9.

Portability problems fixed by Gnulib module strtod-obsolete:

  • This function is missing on some old platforms.

Portability problems not fixed by Gnulib:

  • This function returns +0.0 (not −0.0) for negative underflow on some platforms: glibc 2.7, Cygwin 1.5.x, mingw, MSVC 14.
  • This function cannot distinguish between “nan” and “-nan” on some platforms: glibc 2.7, mingw, MSVC 14.
  • This function fails to correctly parse very long strings on some platforms: Mac OS X 10.5, FreeBSD 6.2, NetBSD 5.0, OpenBSD 4.0, Cygwin, mingw, MSVC 14.
  • This function fails to set errno upon gradual underflow (resulting in a denormalized number) on some platforms: MSVC 14.
  • The replacement function does not always return correctly rounded results.
  • If no conversion could be performed, this function sets errno to EINVAL on some platforms. Portable programs should check for no conversion by comparing str to *endptr, not by inspecting errno.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.69 strtof

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strtof.html

Gnulib module: strtof

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, MSVC 9, Android 4.4.
  • This function returns the wrong end pointer for ‘-0x’ on some platforms: glibc 2.4, Mac OS X 10.5, FreeBSD 6.2.
  • This function fails to parse ‘NaN()’ on some platforms: glibc 2.5, FreeBSD 6.2.
  • This function misparses ‘nan(’ on some platforms: macOS 10.6.6.
  • This function fails to set errno upon overflow on some platforms: mingw 9.0.
  • This function fails to set errno upon underflow on some platforms: Cygwin 2.9, mingw 5.0.

Portability problems not fixed by Gnulib:

  • This function returns +0.0 (not −0.0) for negative underflow on some platforms: glibc 2.7, mingw, MSVC 14.
  • This function cannot distinguish between “nan” and “-nan” on some platforms: glibc 2.7, mingw, MSVC 14.
  • This function returns ‘NaN’ for ‘-NaN’ on some platforms: glibc 2.27, musl libc.
  • This function fails to correctly parse very long strings on some platforms: Mac OS X 10.5, FreeBSD 6.2, NetBSD 5.0, Cygwin, mingw, MSVC 14.
  • This function fails to set errno upon gradual underflow (resulting in a denormalized number) on some platforms: MSVC 14.
  • The replacement function does not always return correctly rounded results.
  • If no conversion could be performed, this function sets errno to EINVAL on some platforms. Portable programs should check for no conversion by comparing str to *endptr, not by inspecting errno.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.70 strtol

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strtol.html

Gnulib module: strtol

Portability problems fixed by Gnulib:

  • This function is missing on some old platforms.
  • This function does not parse the leading ‘0’ when the input string is "0x" and the base is 16 or 0 on some platforms: Minix 3.3, mingw, MSVC 14.
  • This function does not parse binary integers (with a ‘0b’ or ‘0B’ prefix) when the base is 2 or 0 on many platforms.

Portability problems not fixed by Gnulib:

  • If no conversion could be performed, this function sets errno to EINVAL on some platforms. Portable programs should check for no conversion by comparing str to *endptr, not by inspecting errno.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.71 strtold

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strtold.html

Gnulib module: strtold

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, Solaris 9, older Cygwin 1.7.x, MSVC 9, Android 4.4.
  • This function returns a struct, not a long double, on some platforms: HP-UX 11.31/hppa.
  • This function always returns a wrong value on some platforms: mingw 5.0.
  • This function allows whitespace between ‘e’ and the exponent on some platforms: HP-UX 11.31/ia64.
  • This function returns the wrong end pointer for ‘-0x’ on some platforms: glibc-2.3.2, Mac OS X 10.5, Haiku.
  • This function fails to parse Infinities and plain NaNs on some platforms: HP-UX 11.31/ia64.
  • This function fails to parse ‘NaN()’ on some platforms: glibc-2.3.2, mingw, Haiku.
  • This function parses ‘NaN(n-char-sequence)’, but returns the wrong end pointer on some platforms: glibc-2.3.2, mingw, Haiku.
  • This function returns ‘NaN’ for ‘-NaN’ on some platforms: glibc 2.27, musl libc.
  • This function fails to parse C99 hexadecimal floating point on some platforms: mingw.
  • In hexadecimal floats, this function allows whitespace between ‘p’ and the exponent on some platforms: HP-UX 11.31/ia64.
  • This function fails to set errno upon underflow on some platforms: Cygwin 2.9.
  • This function maps denormalized numbers to zero on some platforms: Haiku 2024.
  • This function leaks memory on mingw 5.0 and allocates an unbounded amount of stack on mingw 9.0.

Portability problems not fixed by Gnulib:

  • This function fails to set errno upon gradual underflow (resulting in a denormalized number) on some platforms: MSVC 14.
  • The replacement function does not always return correctly rounded results.
  • If no conversion could be performed, this function sets errno to EINVAL on some platforms. Portable programs should check for no conversion by comparing str to *endptr, not by inspecting errno.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.72 strtoll

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strtoll.html

Gnulib module: strtoll

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11.11, MSVC 9.
  • This function does not parse the leading ‘0’ when the input string is "0x" and the base is 16 or 0 on some platforms: Minix 3.3, mingw, MSVC 14.
  • This function does not parse binary integers (with a ‘0b’ or ‘0B’ prefix) when the base is 2 or 0 on many platforms.

Portability problems not fixed by Gnulib:

  • If no conversion could be performed, this function sets errno to EINVAL on some platforms. Portable programs should check for no conversion by comparing str to *endptr, not by inspecting errno.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.73 strtoul

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strtoul.html

Gnulib module: strtoul

Portability problems fixed by Gnulib:

  • This function is missing on some old platforms.
  • This function does not parse the leading ‘0’ when the input string is "0x" and the base is 16 or 0 on some platforms: Minix 3.3, mingw, MSVC 14.
  • This function does not parse binary integers (with a ‘0b’ or ‘0B’ prefix) when the base is 2 or 0 on many platforms.

Portability problems not fixed by Gnulib:

  • If no conversion could be performed, this function sets errno to EINVAL on some platforms. Portable programs should check for no conversion by comparing str to *endptr, not by inspecting errno.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.74 strtoull

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strtoull.html

Gnulib module: strtoull

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11.11, MSVC 9.
  • This function does not parse the leading ‘0’ when the input string is "0x" and the base is 16 or 0 on some platforms: Minix 3.3, mingw, MSVC 14.
  • This function does not parse binary integers (with a ‘0b’ or ‘0B’ prefix) when the base is 2 or 0 on many platforms.

Portability problems not fixed by Gnulib:

  • If no conversion could be performed, this function sets errno to EINVAL on some platforms. Portable programs should check for no conversion by comparing str to *endptr, not by inspecting errno.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.75 system

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/system.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-system-3.html

Gnulib module: system-posix

Portability problems fixed by Gnulib:

  • The macros WIFSIGNALED, WIFEXITED, WIFSTOPPED, WTERMSIG, WEXITSTATUS, WNOHANG, WUNTRACED, WSTOPSIG are not defined in <stdlib.h> (only in <sys/wait.h>) on some platforms: MirBSD 10.

Portability problems not fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), the command processor used by the system function is cmd.exe, not /bin/sh. Accordingly, the rules for quoting shell arguments containing spaces, quote or other special characters are different.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.76 unlockpt

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/unlockpt.html

Gnulib module: unlockpt

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • This function reports success for invalid file descriptors on some platforms: NetBSD 5.1, Cygwin 1.7.9, Haiku.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.77 unsetenv

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/unsetenv.html

Gnulib module: unsetenv

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11.23, Solaris 9, mingw, MSVC 14.
  • This function has the return type ‘void’ instead of ‘int’ on some platforms: FreeBSD 6.0, NetBSD 1.6, OpenBSD 3.8.
  • On some platforms, this function does not fail with EINVAL when passed an empty string or a string containing ‘=’: FreeBSD 6.0, NetBSD 1.6, OpenBSD 4.7.
  • This function removes only the first value association for the given environment variable, not all of them, on some platforms: Solaris 11.4, Haiku.

Portability problems not fixed by Gnulib:

  • Older versions of POSIX required that unsetenv(NULL) gracefully fail with EINVAL, but not all implementations guarantee this, and the requirement was removed.

Next: , Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.78 wcstombs

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcstombs.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32stombs, provided by Gnulib module c32stombs, operates on 32-bit wide characters and therefore does not have this limitation.

Previous: , Up: Functions in <stdlib.h>   [Contents][Index]

10.46.79 wctomb

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wctomb.html

Gnulib module: wctomb

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.47 Functions in <string.h>

Next: , Up: Functions in <string.h>   [Contents][Index]

10.47.1 memccpy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/memccpy.html

Gnulib module: memccpy

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.2 memchr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/memchr.html

Gnulib module: memchr

Portability problems fixed by Gnulib:

  • This function dereferences too much memory on some platforms: glibc 2.10 on x86_64, IA-64; glibc 2.11 on Alpha, AIX 7.2.
  • This function returns NULL if the character argument is not in the range of an unsigned char on some platforms: Android 5.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.3 memcmp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/memcmp.html

Gnulib module: memcmp

Portability problems fixed by Gnulib:

  • This function fails when comparing 16 bytes or more and with at least one buffer not starting on a 4-byte boundary on some older platforms: NeXTstep/x86.

Portability problems not fixed by Gnulib:

  • This function produces wrong results when the arguments are constant strings and the compiler is clang 6.0.1.

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.4 memcpy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/memcpy.html

Gnulib module: memcpy

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.5 memmem

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/memmem.html

Documentation:

Gnulib module: memmem or memmem-simple

Both modules implement the same replacement for the memmem function with the memmem module providing a replacement on more platforms where the existing memmem function has a quadratic worst-case complexity.

Portability problems fixed by either Gnulib module memmem-simple or memmem:

  • This function is missing on some platforms: Mac OS X 10.5, FreeBSD 5.2.1, OpenBSD 4.0, Minix 3.1.8, HP-UX 11, Solaris 10, mingw, MSVC 14.
  • This function has reversed arguments on some older platforms: Linux libc 5.0.9
  • This function can trigger false positives for long periodic needles on some platforms: glibc 2.12, Cygwin 1.7.7.
  • This function returns incorrect values in some cases, such as when given an empty needle: glibc <= 2.0, macOS 14, AIX 7.2, Solaris 11.3, Cygwin 1.5.x.

Performance problems fixed by Gnulib module memmem:

  • This function has quadratic instead of linear worst-case complexity on some platforms: glibc 2.8, macOS 14, FreeBSD 11.4, NetBSD 8.2, OpenBSD 6.6, AIX 7.2, Solaris 11.4, Cygwin 1.5.x. Note for small needles the replacement may be slower.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.6 memmove

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/memmove.html

Gnulib module: memmove

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.7 memset

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/memset.html

Gnulib module: memset

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.8 memset_explicit

Documentation:

Gnulib module: memset_explicit

The memset_explicit function is an approximation to what is needed, and does not suffice in general to erase information. Although calling memset_explicit should clear the memory in question, the information that was in memory may still be available elsewhere on the machine. Proper implementation of information erasure requires support from levels below C code.

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.36, FreeBSD 13.1, NetBSD 10.0, OpenBSD 7.2, macOS 13, Solaris 11.4, Android API level 33, and many other systems.

Portability problems not fixed by Gnulib:

  • Although the module’s implementation should set the memory on platforms compatible with GCC and on platforms using traditional linkers, it may not set the memory on non-GCC platforms that use whole-program optimization.

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.9 stpcpy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/stpcpy.html

Gnulib module: stpcpy

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 4.4.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.10 stpncpy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/stpncpy.html

Gnulib module: stpncpy

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 4.4.
  • This function has an incompatible return value on some platforms: AIX 5.1.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.
  • This function looks at more bytes of the source string than allowed on some platforms: FreeBSD 15.0/x86_64.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.11 strcat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strcat.html

Gnulib module: string-h

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.12 strchr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strchr.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function cannot work correctly on character strings in some multibyte locales. Gnulib provides an alternative function mbschr that works on character strings in all locales.

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.13 strcmp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strcmp.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.14 strcoll

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strcoll.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function fails, setting errno to EILSEQ, on Solaris 10, in UTF-8 locales, when at least one of the strings contains a Unicode character in a block that was not assigned in Unicode 4.0.

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.15 strcoll_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strcoll_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.16 strcpy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strcpy.html

Gnulib module: string-h

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Note: strcpy (dst, src) is only safe to use when you can guarantee that there are at least strlen (src) + 1 bytes allocated at dst.

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.17 strcspn

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strcspn.html

Gnulib module: strcspn

Portability problems fixed by Gnulib:

  • This function is missing on some old platforms.

Portability problems not fixed by Gnulib:

  • This function cannot work correctly on character strings in multibyte locales. Gnulib provides an alternative function mbscspn that works on character strings in all locales.

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.18 strdup

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strdup.html

Gnulib module: strdup or strdup-posix

Portability problems fixed by either Gnulib module strdup or strdup-posix:

  • This function has no prototype in <string.h> on some old platforms.

Portability problems fixed by Gnulib module strdup-posix:

  • On some platforms, when the function fails it does not set errno: mingw, MSVC 14.
  • On some platforms, when the function fails it might set errno to EAGAIN instead of to ENOMEM. Although POSIX allows EAGAIN, the strdup-posix module insists on ENOMEM which also conforms to POSIX and is GNU-compatible: Solaris 11.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.19 strerror

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strerror.html

Gnulib module: strerror

Portability problems fixed by Gnulib:

  • This function does not support the error values that are specified by POSIX but not defined by the system, on some platforms: OpenBSD 4.0, NonStop Kernel, Cygwin 1.5.x, mingw, MSVC 14.
  • This function reports failure for strerror(0) (by setting errno or using a string similar to out-of-range values), although POSIX requires this to leave errno unchanged and report success, on some platforms: FreeBSD 8.2, NetBSD 10.0, OpenBSD 4.7, macOS 14.
  • This function returns an empty string for out-of-range integers on some platforms: HP-UX 11.

Portability problems not fixed by Gnulib:

Note: The return type of the strerror function is char * in POSIX, with the constraint that “The application shall not modify the string returned.” The Gnulib-overridden strerror function has a return type of const char *. This helps detecting code that attempts to write into that string.

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.20 strerror_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strerror_l.html

Gnulib module: strerror_l

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.5, macOS 14, FreeBSD 12.4, NetBSD 6.1, OpenBSD 6.1, Minix 3.1.8, AIX 7.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 5.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.21 strerror_r

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strerror_r.html

LSB specification:

Gnulib module: strerror_r-posix

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, Minix 3.1.8, HP-UX 11.23, Solaris 9, mingw, MSVC 14.
  • glibc, Cygwin, Android, and AIX+_LINUX_SOURCE_COMPAT have an incompatible version of this function. The POSIX compliant code 
    char *s = (strerror_r (err, buf, buflen) == 0 ? buf : NULL);

    is essentially equivalent to this code using the glibc function: 

    char *s = strerror_r (err, buf, buflen);
  • This function clobbers the strerror buffer on some platforms: Cygwin 1.7.9.
  • This function is sometimes not declared in <string.h> on some platforms: glibc 2.8.
  • The third argument is of type int instead of size_t on some platforms: AIX 5.1.
  • When this function fails, it returns −1 and sets errno, instead of returning the error number, on some platforms: glibc 2.12 with -D_POSIX_C_SOURCE=200112L, AIX 6.1.
  • When this function fails, it corrupts errno, on some platforms: Solaris 10.
  • This function does not support many error values defined in <errno.h> on some platforms: MSVC 14.
  • This function does not support the error values that are specified by POSIX but not defined by the system, on some platforms: OpenBSD 4.0, NonStop Kernel, Cygwin 1.5.x.
  • This function reports failure for strerror_r(0, buf, len), although POSIX requires this to succeed, on some platforms: FreeBSD 8.2.
  • This function produces a different string for 0 than strerror on some platforms: macOS 14.
  • This function always fails when the third argument is less than 80 on some platforms: HP-UX 11.31.
  • When the buffer is too small and the value is in range, this function does not fail, but instead truncates the result and returns 0 on some platforms: AIX 6.1, Haiku 2017.
  • When the value is not in range or the buffer is too small, this function fails to leave a NUL-terminated string in the buffer on some platforms: glibc 2.13, FreeBSD 8.2, Solaris 10.
  • When the value is out of range but the buffer is too small, this function does not always return the longest possible string on some platforms: OpenBSD 4.7.

Portability problems not fixed by Gnulib:

Note: Gnulib has a module xstrerror, with the property that xstrerror (NULL, errnum) returns the value of strerror_r as a freshly allocated string. (Recall that the expression strerror (errnum) is not thread-safe.)

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.22 strlcat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strlcat.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Truncating-Strings.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.37, AIX 7.3.1, HP-UX 11.31, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.23 strlcpy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strlcpy.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Truncating-Strings.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.37, AIX 7.3.1, HP-UX 11.31, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.24 strlen

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strlen.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.25 strncat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strncat.html

Gnulib module: strncat

Portability problems fixed by Gnulib:

  • This function dereferences too much memory on some platforms: Solaris 11.4 on SPARC, Solaris 11.0 on x86.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.26 strncmp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strncmp.html

Gnulib module: strncmp

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.27 strncpy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strncpy.html

Gnulib module: string-h or strncpy

Portability problems fixed by Gnulib module string-h or Gnulib module strncpy:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems fixed by Gnulib module strncpy:

  • This function looks at more bytes of the source string than allowed on some platforms: FreeBSD 15.0/x86_64.

Portability problems not fixed by Gnulib:

Note: This function was designed for the use-case of filling a fixed-size record with a string, before writing it to a file. This function is not appropriate for copying a string into a bounded memory area, because you have no guarantee that the result will be NUL-terminated. Even if you add the NUL byte at the end yourself, this function is inefficient (as it spends time clearing unused memory) and will allow silent truncation to occur, which is not a good behavior for GNU programs. For more details, see https://meyering.net/crusade-to-eliminate-strncpy/.

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.28 strndup

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strndup.html

Gnulib module: strndup

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 10, mingw, MSVC 14.
  • This function does not NUL-terminate the result on some platforms: AIX 5.1.
  • This function does not support zero-length operations on NULL pointers on some platforms: AIX 7.3.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.29 strnlen

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strnlen.html

Gnulib module: strnlen

Portability problems fixed by Gnulib:

  • On some platforms, calls like strnlen (s, maxlen) can crash if s is null-terminated but address arithmetic overflows (i.e., s + maxlen < s): Android 5.0.
  • This function is missing on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, HP-UX 11, Solaris 10, mingw.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.30 strpbrk

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strpbrk.html

Gnulib module: strpbrk

Portability problems fixed by Gnulib:

  • This function is missing on some old platforms.

Portability problems not fixed by Gnulib:

  • This function cannot work correctly on character strings in multibyte locales. Gnulib provides an alternative function mbspbrk that works on character strings in all locales.

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.31 strrchr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strrchr.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function cannot work correctly on character strings in some multibyte locales. Gnulib provides an alternative function mbsrchr that works on character strings in all locales.

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.32 strsignal

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strsignal.html

Gnulib module: strsignal

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11, mingw, MSVC 14.
  • This function does not return a string for out-of-range numbers on some platforms: Solaris, AIX 5.1.
  • This function is declared in unistd.h instead of string.h on some platforms: NetBSD 5.0.

Portability problems not fixed by Gnulib:

  • This function returns const char * instead of char * on some platforms: cygwin 1.5.25, Haiku.

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.33 strspn

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strspn.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function cannot work correctly on character strings in multibyte locales. Gnulib provides an alternative function mbsspn that works on character strings in all locales.

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.34 strstr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strstr.html

Gnulib module: strstr or strstr-simple

Portability problems fixed by either Gnulib module strstr-simple or strstr:

  • This function can trigger memchr bugs on some platforms: glibc 2.10.
  • This function can trigger false positives for long periodic needles on some platforms: glibc 2.12, Cygwin 1.7.7.
  • This function may fail to find matches on some platforms: glibc 2.28.

Portability problems fixed by Gnulib module strstr:

  • This function has quadratic instead of linear worst-case complexity on some platforms: glibc 2.8, macOS 14, FreeBSD 11.4, NetBSD 10.0, OpenBSD 6.1, AIX 7.2, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • This function cannot work correctly on character strings in most multibyte locales. Gnulib provides an alternative function mbsstr that works on character strings in all locales.

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.35 strtok

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strtok.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.36 strtok_r

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strtok_r.html

Gnulib module: strtok_r

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • This function crashes when invoked from code compiled with optimization enabled on some platforms: glibc 2.7.

Portability problems not fixed by Gnulib:

  • This function cannot work correctly on character strings in multibyte locales. Gnulib provides an alternative function mbstok_r that works on character strings in all locales.

Next: , Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.37 strxfrm

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strxfrm.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function has a wrong return value on some platforms: Haiku.

Previous: , Up: Functions in <string.h>   [Contents][Index]

10.47.38 strxfrm_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strxfrm_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.48 Functions in <strings.h>

Next: , Up: Functions in <strings.h>   [Contents][Index]

10.48.1 ffs

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ffs.html

Gnulib module: ffs

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • This function is only defined as an inline function on some platforms: Android 13.

Next: , Previous: , Up: Functions in <strings.h>   [Contents][Index]

10.48.2 ffsl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ffsl.html

Documentation:
man ffsl

Gnulib module: ffsl

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 10.0, OpenBSD 7.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.
  • This function is declared in <strings.h> instead of <string.h> on some platforms: AIX 7.2, Android 13.

Portability problems not fixed by Gnulib:

  • This function is only defined as an inline function on some platforms: Android 13.

Next: , Previous: , Up: Functions in <strings.h>   [Contents][Index]

10.48.3 ffsll

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ffsll.html

Documentation:
man ffsll

Gnulib module: ffsll

Portability problems fixed by Gnulib:

  • This function is missing on many non-glibc platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.
  • This function is declared in <strings.h> instead of <string.h> on some platforms: AIX 7.2, Android 13.
  • This function returns completely wrong values on some platforms: AIX 7.2 in 32-bit mode.

Portability problems not fixed by Gnulib:

  • This function is only defined as an inline function on some platforms: Android 13.

Next: , Previous: , Up: Functions in <strings.h>   [Contents][Index]

10.48.4 strcasecmp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strcasecmp.html

Gnulib module: strcasecmp

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: MSVC 14.
  • This function uses the case mappings of a wrong locale on some platforms: Solaris 11.4, Cygwin 3.5.6.

Portability problems not fixed by Gnulib:

  • This function cannot work correctly on character strings in multibyte locales. Gnulib provides an alternative function mbscasecmp that does a case insensitive comparison of character strings and that works in all locales.

Next: , Previous: , Up: Functions in <strings.h>   [Contents][Index]

10.48.5 strcasecmp_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strcasecmp_l.html

Gnulib module: strcasecmp_l

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 10.0, OpenBSD 6.1, Minix 3.3.0, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 5.1.
  • This function is declared in <string.h> instead of <strings.h> on some platforms: glibc 2.9, macOS 15.
  • This function uses the case mappings of a wrong locale on some platforms: Solaris 11.4, Cygwin 3.5.6.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <strings.h>   [Contents][Index]

10.48.6 strncasecmp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strncasecmp.html

Gnulib module: strncasecmp

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: MSVC 14.
  • This function uses the case mappings of a wrong locale on some platforms: Solaris 11.4, Cygwin 3.5.6.

Portability problems not fixed by Gnulib:

  • This function cannot work correctly on character strings in multibyte locales. Gnulib provides alternative functions mbsncasecmp and mbspcasecmp that do a case insensitive comparison of character strings and that work in all locales.

Previous: , Up: Functions in <strings.h>   [Contents][Index]

10.48.7 strncasecmp_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strncasecmp_l.html

Gnulib module: strncasecmp_l

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 9.0, NetBSD 10.0, OpenBSD 6.1, Minix 3.3.0, AIX 6.1, HP-UX 11, Solaris 11.3, Cygwin 2.5.x, mingw, MSVC 14, Android 5.1.
  • This function is declared in <string.h> instead of <strings.h> on some platforms: glibc 2.9, macOS 15.
  • This function uses the case mappings of a wrong locale on some platforms: Solaris 11.4, Cygwin 3.5.6.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.49 Functions in <sys/ipc.h>

Up: Functions in <sys/ipc.h>   [Contents][Index]

10.49.1 ftok

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ftok.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.50 Functions in <sys/mman.h>

Next: , Up: Functions in <sys/mman.h>   [Contents][Index]

10.50.1 mlock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mlock.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • On Solaris 10 this function accepts char * not void const *, unless you define feature test macros like _POSIX_C_SOURCE or _XOPEN_SOURCE that may undesirably hide other symbols. To work around this problem, callers can limit themselves to either void const * or char const *.

Next: , Previous: , Up: Functions in <sys/mman.h>   [Contents][Index]

10.50.2 mlockall

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mlockall.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 4.1.

Next: , Previous: , Up: Functions in <sys/mman.h>   [Contents][Index]

10.50.3 mmap

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mmap.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, this function may not work correctly across the entire data range of files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • To get anonymous memory, on some platforms, you can use the flags MAP_ANONYMOUS | MAP_PRIVATE and -1 instead of a file descriptor; on others you have to use a read-only file descriptor of /dev/zero.
  • On Solaris 10 this function accepts and returns char * not void *, unless you define feature test macros like _POSIX_C_SOURCE or _XOPEN_SOURCE that may undesirably hide other symbols. To work around this problem, callers can limit themselves to either void * or char * for both arguments and results.
  • On HP-UX, passing a non-NULL first argument, as a hint for the address (even without MAP_FIXED), often causes mmap to fail. Better pass NULL in this case.
  • On HP-UX, MAP_FIXED basically never works. On other platforms, it depends on the circumstances whether memory can be returned at a given address.

Next: , Previous: , Up: Functions in <sys/mman.h>   [Contents][Index]

10.50.4 mprotect

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mprotect.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • This function does not set errno on some platforms: mingw.
  • On AIX, it is not possible to use mprotect on memory regions allocated with malloc.
  • On Solaris 10 this function accepts char * not void *, unless you define feature test macros like _POSIX_C_SOURCE or _XOPEN_SOURCE that may undesirably hide other symbols. To work around this problem, callers can limit themselves to either void * or char *.

Next: , Previous: , Up: Functions in <sys/mman.h>   [Contents][Index]

10.50.5 msync

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/msync.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • On NetBSD, msync takes only two arguments.
  • On Solaris 10 this function accepts char * not void *, unless you define feature test macros like _POSIX_C_SOURCE or _XOPEN_SOURCE that may undesirably hide other symbols. To work around this problem, callers can limit themselves to either void * or char *.

Next: , Previous: , Up: Functions in <sys/mman.h>   [Contents][Index]

10.50.6 munlock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/munlock.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • On Solaris 10 this function accepts char * not void const *, unless you define feature test macros like _POSIX_C_SOURCE or _XOPEN_SOURCE that may undesirably hide other symbols. To work around this problem, callers can limit themselves to either void const * or char const *.

Next: , Previous: , Up: Functions in <sys/mman.h>   [Contents][Index]

10.50.7 munlockall

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/munlockall.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 4.1.

Next: , Previous: , Up: Functions in <sys/mman.h>   [Contents][Index]

10.50.8 munmap

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/munmap.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • On Solaris 10 this function accepts char * not void *, unless you define feature test macros like _POSIX_C_SOURCE or _XOPEN_SOURCE that may undesirably hide other symbols. To work around this problem, callers can limit themselves to either void * or char *.

Next: , Previous: , Up: Functions in <sys/mman.h>   [Contents][Index]

10.50.9 posix_madvise

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_madvise.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 5.1.

Next: , Previous: , Up: Functions in <sys/mman.h>   [Contents][Index]

10.50.10 posix_mem_offset

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_mem_offset.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <sys/mman.h>   [Contents][Index]

10.50.11 posix_typed_mem_get_info

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_typed_mem_get_info.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <sys/mman.h>   [Contents][Index]

10.50.12 posix_typed_mem_open

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_typed_mem_open.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <sys/mman.h>   [Contents][Index]

10.50.13 shm_open

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/shm_open.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.51 Functions in <sys/msg.h>

Next: , Up: Functions in <sys/msg.h>   [Contents][Index]

10.51.1 msgctl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/msgctl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: Functions in <sys/msg.h>   [Contents][Index]

10.51.2 msgget

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/msgget.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: Functions in <sys/msg.h>   [Contents][Index]

10.51.3 msgrcv

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/msgrcv.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 7.1.

Previous: , Up: Functions in <sys/msg.h>   [Contents][Index]

10.51.4 msgsnd

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/msgsnd.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.52 Functions in <sys/resource.h>

Next: , Up: Functions in <sys/resource.h>   [Contents][Index]

10.52.1 getpriority

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getpriority.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <sys/resource.h>   [Contents][Index]

10.52.2 getrlimit

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getrlimit.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getrlimit-1.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where rlim_t is a 32-bit type, this function does not allow to retrieve limits larger than 4 GiB and larger, such as for RLIMIT_FSIZE. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <sys/resource.h>   [Contents][Index]

10.52.3 getrusage

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getrusage.html

Gnulib module: getrusage

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • Many platforms don’t fill in all the fields of struct rusage with meaningful values.
  • Some platforms fill the ru_maxrss field of struct rusage with the maximum resident set size in bytes instead of kilobytes: macOS 26.

Next: , Previous: , Up: Functions in <sys/resource.h>   [Contents][Index]

10.52.4 setpriority

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setpriority.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Previous: , Up: Functions in <sys/resource.h>   [Contents][Index]

10.52.5 setrlimit

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setrlimit.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getrlimit-1.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where rlim_t is a 32-bit type, this function does not allow to set limits 4 GiB and larger, such as for RLIMIT_FSIZE. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.53 Functions in <sys/select.h>

Next: , Up: Functions in <sys/select.h>   [Contents][Index]

10.53.1 FD_CLR

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/FD_CLR.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <sys/select.h>   [Contents][Index]

10.53.2 FD_ISSET

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/FD_ISSET.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <sys/select.h>   [Contents][Index]

10.53.3 FD_SET

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/FD_SET.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <sys/select.h>   [Contents][Index]

10.53.4 FD_ZERO

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/FD_ZERO.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <sys/select.h>   [Contents][Index]

10.53.5 pselect

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pselect.html

Gnulib module: pselect

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11.23, Solaris 9, mingw, MSVC 14.
  • On some platforms, this function fails to detect invalid fds with EBADF, but only if they lie beyond the current maximum open fd: FreeBSD 8.2.

Portability problems not fixed by Gnulib:

  • This function has a slightly incompatible declaration on some platforms: AIX 7.1 (when _ALL_SOURCE is defined).
  • When the sigmask argument is nonnull on platforms that do not natively support this function, race conditions are possible when its gnulib implementation temporarily modifies the signal mask, and the behavior is unspecified in a multi-threaded process.

Previous: , Up: Functions in <sys/select.h>   [Contents][Index]

10.53.6 select

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/select.html

Gnulib module: select

Portability problems fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <sys/select.h> on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), select can only be called on descriptors created by the socket function, not on regular file descriptors.
  • On Windows platforms (excluding Cygwin), error codes from this function are not placed in errno, and WSAGetLastError must be used instead.
  • On some platforms, this function fails to detect invalid fds with EBADF, but only if they lie beyond the current maximum open fd: FreeBSD 8.2.

Portability problems not fixed by Gnulib:

  • When you call select with a timeout, some implementations modify the timeout parameter so that upon return from the function, it contains the amount of time not slept. Other implementations leave the timeout parameter unmodified.
  • Under Windows, when passing a pipe, Gnulib’s select replacement might return 0 even before the timeout has passed. Programs using it with pipes can thus busy wait.
  • On Linux, when some file descriptor refers to a regular file, select may fail, setting errno to EBADF.
  • On Haiku, the maximum allowed value for the first argument is not FD_SETSIZE but FD_SETSIZE / 2.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.54 Functions in <sys/sem.h>

Next: , Up: Functions in <sys/sem.h>   [Contents][Index]

10.54.1 semctl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/semctl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: Functions in <sys/sem.h>   [Contents][Index]

10.54.2 semget

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/semget.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 7.1.

Previous: , Up: Functions in <sys/sem.h>   [Contents][Index]

10.54.3 semop

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/semop.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.55 Functions in <sys/shm.h>

Next: , Up: Functions in <sys/shm.h>   [Contents][Index]

10.55.1 shmat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/shmat.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 7.1.
  • On Linux, the flag SHM_REMAP is needed in order to force shmat to replace existing memory mappings in the specify address range. On other platforms, it is not needed.

Next: , Previous: , Up: Functions in <sys/shm.h>   [Contents][Index]

10.55.2 shmctl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/shmctl.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: Functions in <sys/shm.h>   [Contents][Index]

10.55.3 shmdt

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/shmdt.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 7.1.
  • On Solaris 10 this function accepts char * not void const *, unless you define feature test macros like _POSIX_C_SOURCE or _XOPEN_SOURCE that may undesirably hide other symbols. To work around this problem, callers can limit themselves to either void * or char *.

Previous: , Up: Functions in <sys/shm.h>   [Contents][Index]

10.55.4 shmget

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/shmget.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 7.1.
  • On many platforms (not Linux), SHMMAX is so small that it is unusable for reasonable applications, and/or shmget requires superuser privileges.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.56 Functions in <sys/socket.h>

Next: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.1 accept

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/accept.html

Gnulib module: accept

Portability problems fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <sys/socket.h> on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), the descriptors returned by the accept function cannot be used in calls to read, write, and close; you have to use recv, send, closesocket in these cases instead.
  • On Windows platforms (excluding Cygwin), error codes from this function are not placed in errno, and WSAGetLastError must be used instead.
  • On HP-UX 11, in 64-bit mode, when the macro _HPUX_ALT_XOPEN_SOCKET_API is not defined, this function behaves incorrectly because it is declared to take a pointer to a 64-bit wide socklen_t entity but in fact considers it as a pointer to a 32-bit wide unsigned int entity.

Portability problems not fixed by Gnulib:

  • Some platforms don’t have a socklen_t type; in this case this function’s third argument type is ‘int *’.
  • On some platforms, this function’s third argument type is ‘void *’, not ‘socklen_t *’: Solaris 10, Solaris 11 OmniOS.

Next: , Previous: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.2 accept4

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/accept4.html

Documentation:
man accept4

Gnulib module: accept4

Portability problems fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.9, macOS 14, FreeBSD 6.0, NetBSD 7.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.1, mingw, MSVC 14, Android 4.4. But the replacement function is not atomic; this matters in multi-threaded processes that spawn child processes.

Portability problems not fixed by Gnulib:

  • SOCK_CLOEXEC and SOCK_NONBLOCK may not be defined as they’re also significant to the socket() function.

Next: , Previous: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.3 bind

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/bind.html

Gnulib module: bind

Portability problems fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <sys/socket.h> on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), error codes from this function are not placed in errno, and WSAGetLastError must be used instead.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.4 connect

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/connect.html

Gnulib module: connect

Portability problems fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <sys/socket.h> on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), error codes from this function are not placed in errno, and WSAGetLastError must be used instead.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.5 getpeername

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getpeername.html

Gnulib module: getpeername

Portability problems fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <sys/socket.h> on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), error codes from this function are not placed in errno, and WSAGetLastError must be used instead.
  • On HP-UX 11, in 64-bit mode, when the macro _HPUX_ALT_XOPEN_SOCKET_API is not defined, this function behaves incorrectly because it is declared to take a pointer to a 64-bit wide socklen_t entity but in fact considers it as a pointer to a 32-bit wide unsigned int entity.

Portability problems not fixed by Gnulib:

  • Some platforms don’t have a socklen_t type; in this case this function’s third argument type is ‘int *’.
  • On some platforms, this function’s third argument type is ‘void *’, not ‘socklen_t *’: Solaris 11 OmniOS.

Next: , Previous: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.6 getsockname

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getsockname.html

Gnulib module: getsockname

Portability problems fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <sys/socket.h> on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), error codes from this function are not placed in errno, and WSAGetLastError must be used instead.
  • On HP-UX 11, in 64-bit mode, when the macro _HPUX_ALT_XOPEN_SOCKET_API is not defined, this function behaves incorrectly because it is declared to take a pointer to a 64-bit wide socklen_t entity but in fact considers it as a pointer to a 32-bit wide unsigned int entity.

Portability problems not fixed by Gnulib:

  • Some platforms don’t have a socklen_t type; in this case this function’s third argument type is ‘int *’.
  • On some platforms, this function’s third argument type is ‘void *’, not ‘socklen_t *’: Solaris 11 OmniOS.

Next: , Previous: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.7 getsockopt

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getsockopt.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getsockopt-1.html

Gnulib module: getsockopt

Portability problems fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <sys/socket.h> on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), error codes from this function are not placed in errno, and WSAGetLastError must be used instead.
  • On HP-UX 11, in 64-bit mode, when the macro _HPUX_ALT_XOPEN_SOCKET_API is not defined, this function behaves incorrectly because it is declared to take a pointer to a 64-bit wide socklen_t entity but in fact considers it as a pointer to a 32-bit wide unsigned int entity.

Portability problems not fixed by Gnulib:

  • Some platforms don’t have a socklen_t type; in this case this function’s fifth argument type is ‘int *’.
  • On some platforms, this function’s fifth argument type is ‘void *’, not ‘socklen_t *’: Solaris 11 OmniOS.
  • Many socket options are not available on all platforms.

Next: , Previous: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.8 listen

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/listen.html

Gnulib module: listen

Portability problems fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <sys/socket.h> on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), error codes from this function are not placed in errno, and WSAGetLastError must be used instead.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.9 recv

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/recv.html

Gnulib module: recv

Portability problems fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <sys/socket.h> on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), error codes from this function are not placed in errno, and WSAGetLastError must be used instead.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.10 recvfrom

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/recvfrom.html

Gnulib module: recvfrom

Portability problems fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <sys/socket.h> on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), error codes from this function are not placed in errno, and WSAGetLastError must be used instead.
  • On HP-UX 11, in 64-bit mode, when the macro _HPUX_ALT_XOPEN_SOCKET_API is not defined, this function behaves incorrectly because it is declared to take a pointer to a 64-bit wide socklen_t entity but in fact considers it as a pointer to a 32-bit wide unsigned int entity.

Portability problems not fixed by Gnulib:

  • Some platforms don’t have a socklen_t type; in this case this function’s sixth argument type is ‘int *’.
  • On some platforms, this function’s sixth argument type is ‘void *’, not ‘socklen_t *’: Solaris 11 OmniOS.

Next: , Previous: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.11 recvmsg

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/recvmsg.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.12 send

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/send.html

Gnulib module: send

Portability problems fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <sys/socket.h> on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), error codes from this function are not placed in errno, and WSAGetLastError must be used instead.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.13 sendmsg

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sendmsg.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.14 sendto

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sendto.html

Gnulib module: sendto

Portability problems fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <sys/socket.h> on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), error codes from this function are not placed in errno, and WSAGetLastError must be used instead.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.15 setsockopt

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setsockopt.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-setsockopt-2.html

Gnulib module: setsockopt

Portability problems fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <sys/socket.h> on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), error codes from this function are not placed in errno, and WSAGetLastError must be used instead.

Portability problems not fixed by Gnulib:

  • Many socket options are not available on all platforms.

Next: , Previous: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.16 shutdown

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/shutdown.html

Gnulib module: shutdown

Portability problems fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <sys/socket.h> on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), error codes from this function are not placed in errno, and WSAGetLastError must be used instead.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.17 sockatmark

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sockatmark.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.18 socket

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/socket.html

Gnulib module: socket

Portability problems fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <sys/socket.h> on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), the descriptors returned by the socket function cannot be used in calls to read, write, and close; you have to use recv, send, closesocket in these cases instead.
  • On Windows platforms (excluding Cygwin), error codes from this function are not placed in errno, and WSAGetLastError must be used instead.

Portability problems not fixed by Gnulib:

Previous: , Up: Functions in <sys/socket.h>   [Contents][Index]

10.56.19 socketpair

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/socketpair.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.57 Functions in <sys/stat.h>

Next: , Up: Functions in <sys/stat.h>   [Contents][Index]

10.57.1 chmod

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/chmod.html

Gnulib module: chmod

Portability problems fixed by Gnulib:

  • This function does not fail when the file name argument ends in a slash and (without the slash) names a non-directory, on some platforms: AIX 7.2.
  • This function fails with a wrong error code (EINVAL instead of ENOTDIR) when the file name argument ends in a slash and (without the slash) names a non-directory, on some platforms: mingw, MSVC.

Portability problems not fixed by Gnulib:

  • This function sometimes fails with EACCES when the failure is due to lack of appropriate privileges (EPERM), not to search permission denied on the file name prefix (EACCES): Linux kernel 5.15 with glibc 2.35 and a CIFS v1 file system (see https://bugs.gnu.org/65599).

Next: , Previous: , Up: Functions in <sys/stat.h>   [Contents][Index]

10.57.2 fchmod

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fchmod.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • This function sometimes fails with EACCES when the failure is due to lack of appropriate privileges (EPERM), not to search permission denied on the file name prefix (EACCES): Linux kernel 5.15 with glibc 2.35 and a CIFS v1 file system (see https://bugs.gnu.org/65599).

Next: , Previous: , Up: Functions in <sys/stat.h>   [Contents][Index]

10.57.3 fchmodat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fchmodat.html

Gnulib module: fchmodat

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14. But the replacement function is not safe to be used in libraries and is not thread-safe.
  • This function does not fail when the file name argument ends in a slash and (without the slash) names a non-directory, on some platforms: AIX 7.2.
  • When given the AT_SYMLINK_NOFOLLOW flag, this function fails with errno set to ENOTSUP, even when the file is not a symbolic link: GNU/Linux with glibc 2.31, Cygwin 2.9.

Portability problems not fixed by Gnulib:

  • Some platforms do not allow changing the access bits on symbolic links.
  • This function does not support AT_EMPTY_PATH: Linux kernel 2.6.38.
  • When AT_EMPTY_PATH is used, this function does not allow the file name to be a null pointer: Linux kernel 6.10, Cygwin 3.6, FreeBSD 15.1.
  • If the AT_SYMLINK_NOFOLLOW flag is specified, this function can fail with errno set to EMFILE or ENFILE, and it fails with errno set to EOPNOTSUPP if the /proc file system is not mounted: GNU/Linux with glibc 2.34.
  • This function sometimes fails with EACCES when the failure is due to lack of appropriate privileges (EPERM), not to search permission denied on the file name prefix (EACCES): Linux kernel 5.15 with glibc 2.35 and a CIFS v1 file system (see https://bugs.gnu.org/65599).

Next: , Previous: , Up: Functions in <sys/stat.h>   [Contents][Index]

10.57.4 fstat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fstat.html

Gnulib module: fstat

Portability problems fixed by Gnulib:

  • This function crashes when invoked with invalid arguments on some platforms: MSVC 14.
  • On platforms where off_t is a 32-bit type, fstat may not correctly report the size of files or block devices 2 GiB and larger.. See Large File Support.
  • On Linux/x86 and Linux/x86_64, applications compiled in 32-bit mode cannot access files that happen to have a 64-bit inode number. This can occur with file systems such as XFS (typically on large disks) and NFS. See Large File Support.
  • On macOS 12.6, when this function yields a timestamp with a nonpositive tv_sec value, tv_nsec might be in the range −999999999..−1, representing a negative nanoseconds offset from tv_sec. Solaris 11.4 is similar, except that tv_sec might also be −1000000000.
  • The st_atime, st_ctime, st_mtime fields are affected by the current time zone and by the DST flag of the current time zone on some platforms: mingw, MSVC 14 (when the environment variable TZ is set).

Portability problems not fixed by Gnulib:

  • See sys/stat.h, for general portability problems with struct stat.
  • This function fails if the file descriptor was opened with O_PATH: Linux kernel 3.5.
  • On Cygwin, fstat applied to the file descriptors 0 and 1, returns different st_ino values, even if standard input and standard output are not redirected and refer to the same terminal.

Next: , Previous: , Up: Functions in <sys/stat.h>   [Contents][Index]

10.57.5 fstatat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fstatat.html

Gnulib module: fstatat

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.5.x, mingw, MSVC 14. But when the function is missing, its Gnulib substitute is not safe to be used in libraries and is not thread-safe.
  • On platforms with AT_EMPTY_PATH, this function does not work when AT_EMPTY_PATH is used with a null pointer file name: glibc 2.40, Linux kernel 6.10, Cygwin 3.6, FreeBSD 15.1.
  • On platforms where off_t is a 32-bit type, fstatat may not correctly report the size of files or block devices larger than 2 GB. See Large File Support.
  • On some platforms, fstatat(fd,"file/",buf,flag) succeeds instead of failing with ENOTDIR. Solaris 9.
  • For symlinks, when the argument ends in a slash, some platforms don’t dereference the argument: Solaris 9.
  • On macOS 12.6, when this function yields a timestamp with a nonpositive tv_sec value, tv_nsec might be in the range −999999999..−1, representing a negative nanoseconds offset from tv_sec. Solaris 11.4 is similar, except that tv_sec might also be −1000000000.

Portability problems not fixed by Gnulib:

  • This function does not fail when the second argument is an empty string on some platforms, even when AT_EMPTY_PATH is not used: glibc 2.7, Linux kernel 2.6.38.
  • This function sets st_ino only to the low-order 32 bits of the inode number of a socket or pipe, which thus can disagree with the st_ino obtained by fstat: macOS 14.
  • See sys/stat.h, for general portability problems with struct stat.

Next: , Previous: , Up: Functions in <sys/stat.h>   [Contents][Index]

10.57.6 futimens

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/futimens.html

Gnulib module: futimens

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.5, Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 4.3. However, the replacement function may end up truncating timestamps to worse resolution than supported by the file system.
  • This function returns a bogus value instead of failing with ENOSYS on some platforms: Linux kernel 2.6.21.
  • When using UTIME_OMIT or UTIME_NOW, some systems require the tv_sec argument to be 0, and don’t necessarily handle all file permissions in the manner required by POSIX: Linux kernel 2.6.25.
  • When using UTIME_OMIT for the modification time, but specifying an access time, some systems fail to update the change time: Linux kernel 2.6.32, macOS 14, NetBSD 10.0, Solaris 11.1.
  • Passing AT_FDCWD as the fd argument does not properly fail with EBADF on some systems: glibc 2.11, musl libc, Solaris 11.
  • Out-of-range values of tv_nsec do not lead to a failure on some platforms: NetBSD 10.0, GNU/Hurd with glibc 2.41.

Portability problems not fixed by Gnulib:

  • On file systems mounted with the noatime attribute, this function might not modify the access time as requested: Linux kernel 6.9.
  • This function sets a slightly different time stamp than the requested one: Haiku.
  • Some platforms lack the ability to change the timestamps of a file descriptor, so the replacement can fail with ENOSYS; the gnulib module ‘utimens’ provides a more reliable interface fdutimens.
  • The mere act of using stat modifies the access time of directories on some platforms, so utimensat can only effectively change directory modification time: Cygwin 1.5.x.

Next: , Previous: , Up: Functions in <sys/stat.h>   [Contents][Index]

10.57.7 lstat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lstat.html

Gnulib module: lstat

Portability problems fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, lstat may not correctly report the size of files or block devices 2 GiB and larger. See Large File Support.
  • On Linux/x86 and Linux/x86_64, applications compiled in 32-bit mode cannot access files that happen to have a 64-bit inode number. This can occur with file systems such as XFS (typically on large disks) and NFS. See Large File Support.
  • For symlinks, when the argument ends in a slash, some platforms don’t dereference the argument: Solaris 9.
  • On some platforms, lstat("file/",buf) succeeds instead of failing with ENOTDIR. macOS 14, Solaris 9.
  • On macOS 12.6, when this function yields a timestamp with a nonpositive tv_sec value, tv_nsec might be in the range −999999999..−1, representing a negative nanoseconds offset from tv_sec. Solaris 11.4 is similar, except that tv_sec might also be −1000000000.
  • On Windows platforms (excluding Cygwin), a different name has to be used for the null device, namely "NUL" instead of "/dev/null".
  • On Windows platforms (excluding Cygwin), symlinks are not supported, so lstat does not exist.

Portability problems not fixed by Gnulib:

  • See sys/stat.h, for general portability problems with struct stat.

Next: , Previous: , Up: Functions in <sys/stat.h>   [Contents][Index]

10.57.8 mkdir

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mkdir.html

Gnulib module: sys_stat-h or mkdir

Portability problems fixed by either Gnulib module sys_stat-h or mkdir:

  • This function is declared in different header files (namely, <io.h> or <direct.h>) on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), this function is called _mkdir and takes only one argument. The fix (without Gnulib) is to define a macro like this: 
    #define mkdir ((int (*)()) _mkdir)

    or 

    #define mkdir(path,mode) _mkdir (path)

Portability problems fixed by Gnulib module mkdir:

  • When the argument ends in a slash, the function call fails on some platforms.
  • This function mistakenly succeeds on ‘mkdir("d/./",mode)’ on some platforms: Cygwin 1.5.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <sys/stat.h>   [Contents][Index]

10.57.9 mkdirat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mkdirat.html

Gnulib module: mkdirat

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14. But the replacement function is not safe to be used in libraries and is not thread-safe.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <sys/stat.h>   [Contents][Index]

10.57.10 mkfifo

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mkfifo.html

Gnulib module: mkfifo

Portability problems fixed by Gnulib:

  • This function mishandles trailing slash on some platforms: FreeBSD 7.2, Solaris 9.
  • This function is missing on some platforms; however, the replacement always fails with ENOSYS: mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

  • If the argument exists and is a directory, this function fails with EISDIR instead of the correct EEXIST: HP-UX 11.11.

Next: , Previous: , Up: Functions in <sys/stat.h>   [Contents][Index]

10.57.11 mkfifoat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mkfifoat.html

Gnulib module: mkfifoat

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 12, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 5.1. But the replacement function is not safe to be used in libraries and is not thread-safe.
  • This function does not fail when the file name argument ends in a slash and (without the slash) names a nonexistent file, on some platforms: AIX 7.2.
  • This function does not fail when the file name argument ends in a slash and (without the slash) names a symbolic link, on some platforms: macOS 14.

Portability problems not fixed by Gnulib:

  • The gnulib replacement function always fails with ENOSYS on some platforms: mingw, MSVC 14.
  • If the argument exists and is a directory, the gnulib replacement function fails with EISDIR instead of the correct EEXIST: HP-UX 11.11.

Next: , Previous: , Up: Functions in <sys/stat.h>   [Contents][Index]

10.57.12 mknod

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mknod.html

Gnulib module: mknod

Portability problems fixed by Gnulib:

  • This function requires super-user privileges to create a fifo: FreeBSD 7.2, NetBSD 8.0, OpenBSD 7.9.
  • This function mishandles trailing slash on some platforms: FreeBSD 7.2, Solaris 9.
  • This function does not handle the S_IFIFO flag on some platforms: macOS 14, DragonFly 6.0, Haiku.
  • This function is missing on some platforms; however, the replacement always fails with ENOSYS: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • Use of this function for anything except fifos is not portable, generally requiring super-user privileges and knowledge of supported device numbers.
  • If the argument exists and is a directory, this function fails with EISDIR instead of the correct EEXIST: HP-UX 11.11.

Next: , Previous: , Up: Functions in <sys/stat.h>   [Contents][Index]

10.57.13 mknodat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mknodat.html

Gnulib module: mkfifoat

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 12, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 4.4. But the replacement function is not safe to be used in libraries and is not thread-safe.
  • This function does not fail when the file name argument ends in a slash and (without the slash) names a nonexistent file, on some platforms: AIX 7.2.
  • This function does not handle the S_IFIFO flag on some platforms: Haiku.

Portability problems not fixed by Gnulib:

  • The gnulib replacement function always fails with ENOSYS on some platforms: mingw, MSVC 14.
  • If the argument exists and is a directory, the gnulib replacement function fails with EISDIR instead of the correct EEXIST: HP-UX 11.11.

Next: , Previous: , Up: Functions in <sys/stat.h>   [Contents][Index]

10.57.14 stat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/stat.html

Gnulib module: stat

Portability problems fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, stat may not correctly report the size of files or block devices 2 GiB and larger. See Large File Support.
  • On Linux/x86 and Linux/x86_64, applications compiled in 32-bit mode cannot access files that happen to have a 64-bit inode number. This can occur with file systems such as XFS (typically on large disks) and NFS. See Large File Support.
  • The st_atime, st_ctime, st_mtime fields are affected by the current time zone and by the DST flag of the current time zone on some platforms: mingw, MSVC 14 (when the environment variable TZ is set).
  • On MSVC 14, this function fails with error ENOENT on files such as ‘C:\pagefile.sys’ and on directories such as ‘C:\System Volume Information’.
  • On some platforms, stat("link-to-file/",buf) succeeds instead of failing with ENOTDIR. macOS 14, FreeBSD 7.2, AIX 7.1, Solaris 9, mingw64.
  • On some platforms, stat(".",buf) and stat("./",buf) give different results: mingw, MSVC 14.
  • On mingw up to 14.0.0, the st_mode field of stat("NUL",buf) is bogus, suggesting that NUL is a regular file.
  • On macOS 12.6, when this function yields a timestamp with a nonpositive tv_sec value, tv_nsec might be in the range −999999999..−1, representing a negative nanoseconds offset from tv_sec. Solaris 11.4 is similar, except that tv_sec might also be −1000000000.
  • On Windows platforms (excluding Cygwin), a different name has to be used for the null device, namely "NUL" instead of "/dev/null".

Portability problems not fixed by Gnulib:

  • See sys/stat.h, for general portability problems with struct stat.
  • Cygwin’s stat function sometimes sets errno to EACCES when ENOENT would be more appropriate.
  • This function sets st_ino only to the low-order 32 bits of the inode number of a socket or pipe, which thus can disagree with the st_ino obtained by fstat: macOS 14.
  • Because of the definition of struct stat, it is not possible to portably replace stat via an object-like macro. Therefore, expressions such as (islnk ? lstat : stat) (name, buf) are not portable, and should instead be written islnk ? lstat (name, buf) : stat (name, buf).

Next: , Previous: , Up: Functions in <sys/stat.h>   [Contents][Index]

10.57.15 umask

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/umask.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Previous: , Up: Functions in <sys/stat.h>   [Contents][Index]

10.57.16 utimensat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/utimensat.html

Gnulib module: utimensat

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.5, Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 3.0. However, the replacement function may end up truncating timestamps to worse resolution than supported by the file system. Furthermore, the replacement function is not safe to be used in libraries and is not thread-safe.
  • This function returns a bogus value instead of failing with ENOSYS on some platforms: Linux kernel 2.6.21.
  • This function fails with ENOSYS if passed the flag AT_SYMLINK_NOFOLLOW on a regular file: Linux kernel 2.6.22.
  • When using UTIME_OMIT or UTIME_NOW, some systems require the tv_sec argument to be 0, and don’t necessarily handle all file permissions in the manner required by POSIX: Linux kernel 2.6.25.
  • When using UTIME_OMIT for the modification time, but specifying an access time, some systems fail to update the change time: Linux kernel 2.6.32, macOS 14, NetBSD 10.0, Solaris 11.1.
  • Out-of-range values of tv_nsec do not lead to a failure on some platforms: Linux kernel 2.6.22.19 on hppa, NetBSD 10.0, GNU/Hurd with glibc 2.41.
  • On some platforms, this function mis-handles a trailing slash: AIX 7.2.

Portability problems not fixed by Gnulib:

  • On file systems mounted with the noatime attribute, this function might not modify the access time as requested: Linux kernel 6.9.
  • When AT_EMPTY_PATH is used, this function does not allow the file name to be a null pointer: Linux kernel 6.10, Cygwin 3.6, FreeBSD 15.1.
  • This function ignores the flag AT_SYMLINK_NOFOLLOW: Linux kernel 6.8 on a CIFS file system.
  • This function sets a slightly different time stamp than the requested one: Haiku.
  • On some platforms, timestamps of symbolic links cannot be modified, so the replacement fails with ENOSYS if passed the flag AT_SYMLINK_NOFOLLOW on a symlink.
  • The mere act of using lstat modifies the access time of symlinks on some platforms, so utimensat with AT_SYMLINK_NOFOLLOW can only effectively change modification time: Cygwin.
  • The mere act of using stat modifies the access time of directories on some platforms, so utimensat can only effectively change directory modification time: Cygwin 1.5.x.

The gnulib module fdutimensat provides a similar interface.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.58 Functions in <sys/statvfs.h>

Next: , Up: Functions in <sys/statvfs.h>   [Contents][Index]

10.58.1 fstatvfs

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fstatvfs.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where f_blocks in ‘struct statvfs’ is a 32-bit value, this function may not work correctly on files systems larger than 4 TiB. See Large File Support. This affects glibc/Hurd, HP-UX 11, Solaris.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, mingw, MSVC 14, Android 4.3.
  • This function fails if the file descriptor was opened with O_PATH: Linux kernel 3.11.

Previous: , Up: Functions in <sys/statvfs.h>   [Contents][Index]

10.58.2 statvfs

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/statvfs.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where f_blocks in ‘struct statvfs’ is a 32-bit value, this function may not work correctly on files systems larger than 4 TiB. See Large File Support. This affects glibc/Hurd, HP-UX 11, Solaris.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, mingw, MSVC 14, Android 4.3.
  • This function can hang if it stats all preceding entries in /proc/mounts, and any of those file systems are hard-mounted and not available. This affects Linux < 2.6.36.

Gnulib provides a module fsusage that provides similar information as statvfs.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.59 Functions in <sys/time.h>

Up: Functions in <sys/time.h>   [Contents][Index]

10.59.1 utimes

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/utimes.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • On some platforms, this function mis-handles a trailing slash: FreeBSD 7.2, Solaris 9.
  • This function cannot set full timestamp resolution. In particular, some platforms incorrectly round rather than truncate. Use utimensat(AT_FDCWD,file,times,0), or the gnulib module utimens, instead.
  • On file systems mounted with the noatime attribute, this function might not modify the access time as requested: Linux kernel 6.9.
  • On some platforms, utimes (file, NULL) fails to set the file’s timestamp to the current time: glibc 2.3.3.
  • On some platforms, utimes failed on read-only files when utime worked fine. glibc 2.2.5.
  • This function sets a slightly different time stamp than the requested one: Haiku.
  • On OS/2, this function cannot set the timestamp to earlier than the year 1980 in local time.
  • On OS/2, this function cannot set the timestamp to an odd number of seconds.
  • On OS/2, this function does not work on an opened file.

Extension: Gnulib provides a module ‘utimens’ that works around these problems and can set the time with nanosecond resolution (as far as supported by the file system).

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.60 Functions in <sys/times.h>

Up: Functions in <sys/times.h>   [Contents][Index]

10.60.1 times

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/times.html

Gnulib module: times

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • There is no function on Windows to measure consumed process child times, thus the tms_cutime and tms_cstime will always be 0 when the module is used.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.61 Functions in <sys/uio.h>

Next: , Up: Functions in <sys/uio.h>   [Contents][Index]

10.61.1 readv

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/readv.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Previous: , Up: Functions in <sys/uio.h>   [Contents][Index]

10.61.2 writev

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/writev.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.62 Functions in <sys/utsname.h>

Up: Functions in <sys/utsname.h>   [Contents][Index]

10.62.1 uname

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/uname.html

Gnulib module: uname

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.63 Functions in <sys/wait.h>

Next: , Up: Functions in <sys/wait.h>   [Contents][Index]

10.63.1 wait

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wait.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <sys/wait.h>   [Contents][Index]

10.63.2 waitid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/waitid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 7.1, OpenBSD 7.2, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14.
  • As of 2005, no system is known on which waitid with flag WNOWAIT works correctly.

Previous: , Up: Functions in <sys/wait.h>   [Contents][Index]

10.63.3 waitpid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/waitpid.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-waitpid-3.html

Gnulib module: waitpid

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.64 Functions in <syslog.h>

Next: , Up: Functions in <syslog.h>   [Contents][Index]

10.64.1 closelog

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/closelog.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <syslog.h>   [Contents][Index]

10.64.2 openlog

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/openlog.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <syslog.h>   [Contents][Index]

10.64.3 setlogmask

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setlogmask.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Previous: , Up: Functions in <syslog.h>   [Contents][Index]

10.64.4 syslog

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/syslog.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.65 Functions in <termios.h>

Next: , Up: Functions in <termios.h>   [Contents][Index]

10.65.1 cfgetispeed

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cfgetispeed.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Functions in <termios.h>   [Contents][Index]

10.65.2 cfgetospeed

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cfgetospeed.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Functions in <termios.h>   [Contents][Index]

10.65.3 cfsetispeed

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cfsetispeed.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Functions in <termios.h>   [Contents][Index]

10.65.4 cfsetospeed

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cfsetospeed.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Functions in <termios.h>   [Contents][Index]

10.65.5 tcdrain

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tcdrain.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4.
  • On some platforms, tcdrain on a non-tty fails with errno set to EINVAL or, on Mac OS X, also EOPNOTSUPP or ENODEV, rather than ENOTTY.

Next: , Previous: , Up: Functions in <termios.h>   [Contents][Index]

10.65.6 tcflow

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tcflow.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Functions in <termios.h>   [Contents][Index]

10.65.7 tcflush

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tcflush.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4.
  • On some platforms, tcflush of TCIFLUSH on a non-tty fails with errno set to EINVAL rather than ENOTTY.
  • On some platforms, tcflush of TCOFLUSH on a non-tty fails with errno set to EINVAL or, on Mac OS X, also EOPNOTSUPP or ENODEV, rather than ENOTTY.

Next: , Previous: , Up: Functions in <termios.h>   [Contents][Index]

10.65.8 tcgetattr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tcgetattr.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Functions in <termios.h>   [Contents][Index]

10.65.9 tcgetsid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tcgetsid.html

Gnulib module: tcgetsid

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, OpenBSD 4.5, Minix 3.1.8, Cygwin 1.7.9, mingw, MSVC 14, Android 4.4.
  • The declaration of this function in C++ compilation units has C++ linkage, not C linkage, on some platforms: HP-UX 11.00.

Portability problems not fixed by Gnulib:

  • This function always fails on some platforms: FreeBSD 6.0, Cygwin 1.7.8, mingw, MSVC 14.
  • This function returns int instead of pid_t on some platforms: Cygwin 1.7.11.

Next: , Previous: , Up: Functions in <termios.h>   [Contents][Index]

10.65.10 tcgetwinsize

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tcgetwinsize.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.42, macOS 14, FreeBSD 12.0, NetBSD 8.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <termios.h>   [Contents][Index]

10.65.11 tcsendbreak

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tcsendbreak.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Functions in <termios.h>   [Contents][Index]

10.65.12 tcsetattr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tcsetattr.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4.

Previous: , Up: Functions in <termios.h>   [Contents][Index]

10.65.13 tcsetwinsize

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tcsetwinsize.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.42, macOS 14, FreeBSD 12.0, NetBSD 8.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.66 Functions in <threads.h>

Next: , Up: Functions in <threads.h>   [Contents][Index]

10.66.1 call_once

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.2.1.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/call_once.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Call-Once.html.

Gnulib module: call_once

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

  • This function makes applications hang forever on some platforms: Cygwin 3.5.3.
  • This function does not work on some platforms: Haiku.

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.2 cnd_broadcast

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.3.1.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cnd_broadcast.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Condition-Variables.html.

Gnulib module: cnd

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.3 cnd_destroy

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.3.2.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cnd_destroy.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Condition-Variables.html.

Gnulib module: cnd

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.4 cnd_init

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.3.3.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cnd_init.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Condition-Variables.html.

Gnulib module: cnd

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.5 cnd_signal

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.3.4.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cnd_signal.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Condition-Variables.html.

Gnulib module: cnd

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.6 cnd_timedwait

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.3.5.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cnd_timedwait.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Condition-Variables.html.

Gnulib module: cnd

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

  • This function sometimes waits indefinitely instead of up to the specified time point, on some platforms (glibc/Linux, musl libc) in some hypervisors: VirtualBox 6.1.50_Ubuntu with paravirtualization set to "Default" or "KVM".

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.7 cnd_wait

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.3.6.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/cnd_wait.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Condition-Variables.html.

Gnulib module: cnd

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.8 mtx_destroy

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.4.1.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mtx_destroy.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Mutexes.html.

Gnulib module: mtx

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.9 mtx_init

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.4.2.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mtx_init.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Mutexes.html.

Gnulib module: mtx

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.10 mtx_lock

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.4.3.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mtx_lock.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Mutexes.html.

Gnulib module: mtx

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.11 mtx_timedlock

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.4.4.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mtx_timedlock.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Mutexes.html.

Gnulib module: mtx

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.12 mtx_trylock

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.4.5.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mtx_trylock.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Mutexes.html.

Gnulib module: mtx

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.13 mtx_unlock

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.4.6.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mtx_unlock.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Mutexes.html.

Gnulib module: mtx

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.14 thrd_create

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.5.1.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/thrd_create.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Thread-Management.html.

Gnulib module: thrd

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.
  • This function uses an incorrectly defined thrd_start_t on some platforms: AIX 7.2.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.15 thrd_current

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.5.2.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/thrd_current.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Thread-Management.html.

Gnulib module: thrd

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.16 thrd_detach

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.5.3.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/thrd_detach.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Thread-Management.html.

Gnulib module: thrd

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.17 thrd_equal

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.5.4.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/thrd_equal.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Thread-Management.html.

Gnulib module: thrd

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.18 thrd_exit

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.5.5.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/thrd_exit.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Thread-Management.html.

Gnulib module: thrd

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.
  • The exit code provided to this function is discarded on some platforms: AIX 7.3.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.19 thrd_join

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.5.6.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/thrd_join.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Thread-Management.html.

Gnulib module: thrd

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.
  • This function never stores an exit code on some platforms: AIX 7.3.1.
  • This function crashes when the second argument is NULL on some platforms: Solaris 11.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.20 thrd_sleep

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.5.7.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/thrd_sleep.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Thread-Management.html.

Gnulib module: thrd

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.21 thrd_yield

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.5.8.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/thrd_yield.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Thread-Management.html.

Gnulib module: thrd

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.22 tss_create

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.6.1.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tss_create.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Thread_002dlocal-Storage.html.

Gnulib module: tss

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.23 tss_delete

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.6.2.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tss_delete.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Thread_002dlocal-Storage.html.

Gnulib module: tss

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.24 tss_get

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.6.3.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tss_get.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Thread_002dlocal-Storage.html.

Gnulib module: tss

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Previous: , Up: Functions in <threads.h>   [Contents][Index]

10.66.25 tss_set

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.28.6.4.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tss_set.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/ISO-C-Thread_002dlocal-Storage.html.

Gnulib module: tss

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 9.3, NetBSD 8.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.1.x, mingw, MSVC 14, Android API level 29.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.67 Functions in <time.h>

Next: , Up: Functions in <time.h>   [Contents][Index]

10.67.1 asctime

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/asctime.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is deprecated in C23. Likewise, POSIX says this function is obsolescent and it is planned to be removed in a future version. Portable applications can use strftime (or even sprintf) instead. However, strftime is locale dependent.
  • This function may overflow its internal buffer if its argument specifies a year before 1000 or after 9999. See ctime.
  • Although it is tempting to call this function on the value that functions like localtime return, this is typically a mistake. On most current platforms, these functions return a null pointer for timestamps out of range, and this function has undefined behavior in that case.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.2 asctime_r

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/asctime_r.html

Gnulib module: extensions

Portability problems fixed by Gnulib:

  • This function has an incompatible declaration on some platforms: Solaris 11.4 (when _POSIX_PTHREAD_SEMANTICS is not defined).

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • This function is removed in POSIX.1-2024. Use the function strftime (or even sprintf) instead. However, strftime is locale dependent.
  • This function may overflow its output buffer if its argument specifies a year before 1000 or after 9999. See ctime.
  • Although it is tempting to call this function on the value that functions like localtime return, this is typically a mistake. On most current platforms, these functions return a null pointer for timestamps out of range, and this function has undefined behavior in that case.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.3 clock

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/clock.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.4 clock_getcpuclockid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/clock_getcpuclockid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.11, FreeBSD 6.0, NetBSD 7.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.9, mingw, MSVC 14, Android 5.1.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.5 clock_getres

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/clock_getres.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.11, Minix 3.1.8, mingw, MSVC 14.
  • On many platforms, this function returns a value other than the clock resolution of clock_gettime, i.e., the minimum distance between differing timestamps. For example, on AIX 7.2 it returns 10 milliseconds even though the clock resolution is 1 microsecond. Conversely, on GNU/Linux it typically returns 1 nanosecond even though the clock resolution may be greater.

The Gnulib module gettime-res is a partial substitute; it implements the CLOCK_REALTIME functionality of clock_getres, and fixes the too-high resolution bug of platforms like AIX 7.2.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.6 clock_gettime

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/clock_gettime.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.11, Minix 3.1.8, mingw, MSVC 14.
  • This function leaves the upper 32 bits of the tv_sec field of the result uninitialized on some platforms: mingw in 32-bit mode.

The Gnulib modules gettime and timespec_get are partial substitutes; they implement the CLOCK_REALTIME functionality of clock_gettime.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.7 clock_nanosleep

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/clock_nanosleep.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.11, FreeBSD 11.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 9, Cygwin 1.7.9, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.8 clock_settime

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/clock_settime.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.11, Minix 3.1.8, Cygwin 1.7.9, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.9 ctime

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ctime.html

Gnulib module: ctime

Portability problems fixed by Gnulib:

  • On native Windows platforms (mingw, MSVC), this function works incorrectly when the environment variable TZ has been set by Cygwin.

Portability problems not fixed by Gnulib:

  • This function is deprecated in C23. Likewise, POSIX says this function is obsolescent and it is planned to be removed in a future version. Portable applications can use localtime_r and strftime (or even sprintf) instead. However, localtime_r can fail and strftime is locale dependent.
  • This function may overflow its internal buffer if its argument specifies a time before the year 1000 or after the year 9999.
  • This function may dereference an internal null pointer if its argument specifies a time before the year INT_MIN+1900 or after the year INT_MAX+1900.
  • The ctime function need not be reentrant, and consequently is not required to be thread safe. Implementations of ctime typically write the timestamp into static buffer. If two threads call ctime at roughly the same time, you might end up with the wrong date in one of the threads, or some undefined string.
  • Native Windows platforms (mingw, MSVC) support only a subset of time zones supported by GNU or specified by POSIX. See tzset.

Although ctime and related functions asctime, asctime_r and ctime_r formerly were plausible to use, they are now unsafe in general, and should be avoided.

Decades ago when time_t was narrow and there was no strftime or internationalization, code could call these functions and then select the parts needed. For example, in Unix 7th Edition /usr/src/cmd/ls.c (1979): 

cp = ctime(&p->lmtime);
if(p->lmtime < year)
        printf(" %-7.7s %-4.4s ", cp+4, cp+20); else
        printf(" %-12.12s ", cp+4);

This had well-defined behavior when time_t was only 32 bits and so was OK for circa 1979 platforms.

However, today’s platforms have a time_t so wide that the year might not be in the range [1000, 9999]. In this case the behavior of ctime is undefined and some platforms behave badly, overrunning a buffer or dereferencing an internal null pointer; and even on platforms where no undefined behavior occurs, the 7th Edition code generates wrong output for out-of-range years, because it incorrectly assumes that every year is represented by exactly four digits.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.10 ctime_r

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ctime_r.html

Gnulib module: extensions

Portability problems fixed by Gnulib:

  • This function has an incompatible declaration on some platforms: Solaris 11.4 (when _POSIX_PTHREAD_SEMANTICS is not defined).

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • This function is removed in POSIX.1-2024. Use the functions localtime_r and strftime (or even sprintf) instead. However, localtime_r can fail and strftime is locale dependent.
  • This function may overflow its output buffer if its argument specifies a time before the year 1000 or after the year 9999. See ctime.
  • This function may dereference an internal null pointer if its argument specifies a time before the year INT_MIN+1900 or after the year INT_MAX+1900.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.11 daylight

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/daylight.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable’s contents are unreliable if you use a geographical TZ setting like TZ="America/Los_Angeles".
  • This variable is missing on some platforms: FreeBSD 14.0, OpenBSD 5.7.
  • This variable is called _daylight on some platforms: mingw with -DNO_OLDNAMES, MSVC.
  • The address of this variable is not a compile-time constant on some platforms: mingw, MSVC.
  • Native Windows platforms (mingw, MSVC) support only a subset of time zones supported by GNU or specified by POSIX. See tzset.

This variable is vestigial: it is not needed and does not suffice in general. It is planned to be removed from a future version of POSIX. A more portable way of getting the UTC offset is to use strftime with the %z format. See strftime.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.12 difftime

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/difftime.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.13 getdate

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getdate.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 14.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Gnulib provides a module parse-datetime that contains a function parse_datetime that has similar functionality as the getdate function.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.14 getdate_err

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getdate_err.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on some platforms: FreeBSD 14.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.15 gmtime

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/gmtime.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • On some platforms, this function yields incorrect values for timestamps before the year 1: MacOS X 10.5, Solaris 11.3.
  • On some platforms, this function returns NULL for arguments < -43200, that is, for timestamps before 1969-12-31 12:00:00 UTC: mingw, MSVC.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.16 gmtime_r

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/gmtime_r.html

Gnulib module: time_r

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • This function is not declared unless _REENTRANT is defined, on some platforms: HP-UX 11.

Portability problems not fixed by Gnulib:

  • On some platforms, this function yields incorrect values for timestamps before the year 1: MacOS X 10.5, Solaris 11.3.
  • This function sets the field tm_zone to "GMT" instead of "UTC" on some platforms: glibc, NetBSD, OpenBSD 7.7, Minix, Cygwin, Android.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.17 localtime

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/localtime.html

Gnulib module: localtime

Portability problems fixed by Gnulib:

  • On native Windows platforms (mingw, MSVC), this function works incorrectly when the environment variable TZ has been set by Cygwin.

Portability problems not fixed by Gnulib:

  • On some platforms, this function loops forever for values near extrema (such as the year -2**31): Mac OS X 10.6. You can use the time_rz module to work around the problem.
  • On some platforms, this function returns nonsense values for unsupported arguments (like 2^56), rather than failing: FreeBSD 10.
  • On some platforms, this function yields incorrect values for timestamps before the year 1: MacOS X 10.5, Solaris 11.3.
  • On some platforms, this function returns NULL for negative arguments, that is, for timestamps before 1970-01-01 00:00:00 local time: mingw, MSVC.
  • Native Windows platforms (mingw, MSVC) support only a subset of time zones supported by GNU or specified by POSIX. See tzset.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.18 localtime_r

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/localtime_r.html

Gnulib module: time_r

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • This function is not declared unless _REENTRANT is defined, on some platforms: HP-UX 11.

Portability problems not fixed by Gnulib:

  • On some platforms, this function loops forever for values near extrema (such as the year -2**31): Mac OS X 10.6. You can use the time_rz module to work around the problem.
  • On some platforms, this function returns nonsense values for unsupported arguments (like 2^56), rather than failing: FreeBSD 10.
  • On some platforms, this function yields incorrect values for timestamps before the year 1: MacOS X 10.5, Solaris 11.3.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.19 mktime

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mktime.html

Gnulib module: mktime

Portability problems fixed by Gnulib:

  • On native Windows platforms (mingw, MSVC), this function works incorrectly when the environment variable TZ has been set by Cygwin.
  • mktime may go into an endless loop on some platforms.
  • mktime may occasionally return wrong results on some platforms.

Portability problems not fixed by Gnulib:

  • On some platforms, this function yields incorrect values for timestamps before the year 1: MacOS X 10.5, Solaris 11.3.
  • Native Windows platforms (mingw, MSVC) support only a subset of time zones supported by GNU or specified by POSIX. See tzset.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.20 nanosleep

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/nanosleep.html

Gnulib module: nanosleep

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • This function mishandles large arguments when interrupted by a signal on some platforms: Linux 64-bit, Solaris 64-bit.
  • This function cannot sleep longer than 49.7 days on some platforms: Cygwin 1.5.x.
  • This function does not fail when passed a negative nanosecond value on some platforms: newer 32-bit mingw.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.21 strftime

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strftime.html

Gnulib module: strftime-fixes

Portability problems fixed by Gnulib:

  • On native Windows platforms (mingw, MSVC), this function works incorrectly when the environment variable TZ has been set by Cygwin.

Portability problems not fixed by Gnulib:

  • The %c specifier does not work with a time retrieved through gmtime or gmtime_r, since it outputs also the current time zone, on some platforms: glibc 2.30, NetBSD 10.0, Solaris 11.4.
  • The %c specifier produces no weekday name and no month name, only a potentially ambiguous numerical output, on some platforms: mingw, MSVC.
  • The %h specifier produces empty output on some platforms: mingw, MSVC.
  • The %r specifier produces empty output on some platforms: mingw, MSVC.
  • The %r specifier produces empty output, at least in a French locale, on some platforms: macOS 12.5, FreeBSD 14.0.
  • The %r specifier includes an AM/PM indicator, at least in a French locale, on some platforms: NetBSD 10.0, Solaris 11.4.
  • The %p specifier produces non-empty output, at least in a French locale, on some platforms: NetBSD 10.0, Solaris 11.4.
  • The Windows C runtime library (which is used by MinGW) does not support the %e specifier (and possibly the other more recent SUS specifiers too, i.e., %C, %D, %h, %n, %r, %R, %t, and %T).
  • Native Windows platforms (mingw, MSVC) support only a subset of time zones supported by GNU or specified by POSIX. See tzset.

Extension: Gnulib offers a module ‘nstrftime’ that provides an nstrftime function with various GNU extensions.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.22 strftime_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strftime_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.23 strptime

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/strptime.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-strptime-3.html

Gnulib module: strptime

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.24 time

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/time.html

Gnulib module: time

Portability problems fixed by Gnulib:

  • This function is not consistent with gettimeofday and timespec_get on some platforms: glibc 2.31 or newer on Linux, FreeBSD 14.0, AIX 7.2, native Windows. Namely, in the first 1 to 2.5 milliseconds of every second (or, on AIX and Windows, in the first 5 milliseconds of every second), time returns a value that is one less than the tv_sec part of the return value of gettimeofday or timespec_get.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.25 timegm

Documentation:

Gnulib module: timegm

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 11.3, mingw, MSVC 14, Android 3.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.26 timer_create

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/timer_create.html

Gnulib module: timer-time

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.11, FreeBSD 6.4, Minix 3.1.8, mingw, MSVC 14.
  • This function fails with ENOSYS on some platforms: OpenBSD 4.9.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.27 timer_delete

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/timer_delete.html

Gnulib module: timer-time

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.11, FreeBSD 6.4, Minix 3.1.8, mingw, MSVC 14.
  • This function fails with ENOSYS on some platforms: OpenBSD 4.9.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.28 timer_getoverrun

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/timer_getoverrun.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.11, FreeBSD 6.0, Minix 3.1.8, Cygwin 2.11.x, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.29 timer_gettime

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/timer_gettime.html

Gnulib module: timer-time

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.11, FreeBSD 6.4, Minix 3.1.8, mingw, MSVC 14.
  • This function fails with ENOSYS on some platforms: OpenBSD 4.9.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.30 timer_settime

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/timer_settime.html

Gnulib module: timer-time

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.11, FreeBSD 6.4, Minix 3.1.8, mingw, MSVC 14.
  • This function fails with ENOSYS on some platforms: OpenBSD 4.9.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.31 timespec_get

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.29.2.6

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/timespec_get.html

Gnulib module: timespec_get

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.15, macOS 10.14, FreeBSD 11.0, NetBSD 7.1, OpenBSD 6.0, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.5.x, mingw with MSVCRT, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.32 timespec_getres

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.29.2.7

Gnulib module: timespec_getres

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.33, macOS 12, FreeBSD 14.0, NetBSD 9.2, OpenBSD 7.0, Minix 3.3.0, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 2.9, mingw, MSVC 14, Android API level 34.

Portability problems not fixed by Gnulib:

  • On some platforms, this function returns a value other than the clock resolution of timespec_get, i.e., the minimum distance between differing timestamps. For example, on GNU/Linux it typically returns 1 nanosecond regardless of the actual clock resolution.

The Gnulib module gettime-res is a partial substitute; it implements the TIME_UTC functionality of timespec_getres.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.33 timezone

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/timezone.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable’s contents are unreliable if you use a geographical TZ setting like TZ="America/Los_Angeles".
  • This variable is missing (and instead, a function named timezone exists) on some platforms: FreeBSD 14.0, OpenBSD 5.7.
  • This variable is called _timezone on some platforms: mingw with -DNO_OLDNAMES, MSVC.
  • The address of this variable is not a compile-time constant on some platforms: mingw, MSVC.
  • Native Windows platforms (mingw, MSVC) support only a subset of time zones supported by GNU or specified by POSIX. See tzset.

This variable is vestigial: it is not needed and does not suffice in general. It is planned to be removed from a future version of POSIX. A more portable way of getting the UTC offset is to use strftime with the %z format. See strftime.

Next: , Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.34 tzname

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tzname.html

Gnulib module: tzname

Portability problems fixed by Gnulib:

  • This variable is called _tzname on some platforms: mingw with -DNO_OLDNAMES, MSVC.

Portability problems not fixed by Gnulib:

  • This variable’s contents are unreliable if you use a geographical TZ setting like TZ="America/Los_Angeles".
  • The address of this variable is not a compile-time constant on some platforms: Cygwin, mingw, MSVC.
  • Native Windows platforms (mingw, MSVC) support only a subset of time zones supported by GNU or specified by POSIX. See tzset.

This variable is vestigial: it is not needed and does not suffice in general. It is planned to be removed from a future version of POSIX. A more portable way of getting the time zone abbreviation is to use strftime with the %Z format. See strftime.

Previous: , Up: Functions in <time.h>   [Contents][Index]

10.67.35 tzset

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tzset.html

Gnulib module: tzset

Portability problems fixed by Gnulib:

  • On native Windows platforms (mingw, MSVC), this function works incorrectly when the environment variable TZ has been set by Cygwin.

Portability problems not fixed by Gnulib:

  • Native Windows platforms (mingw, MSVC) support only a subset of POSIX-specified values for the TZ environment variable, consisting of a time zone abbreviation containing exactly three ASCII letters with no daylight saving time or angle brackets, and with no support for tz database settings like TZ='America/New_York'. Even this subset does not work on applications built via the Universal Windows Platform, as it does not make environment variables like TZ available to applications.
  • Older POSIX platforms do not support angle brackets in TZ values, as this feature was added in IEEE Std 1003.1-2001.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.68 Functions in <uchar.h>

Next: , Up: Functions in <uchar.h>   [Contents][Index]

10.68.1 c8rtomb

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on most platforms: glibc 2.35, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <uchar.h>   [Contents][Index]

10.68.2 c16rtomb

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.30.1.4.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/c16rtomb.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on most non-glibc platforms: glibc 2.15, macOS 14, FreeBSD 6.4, NetBSD 10.0, OpenBSD 7.3, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.4.x, mingw, MSVC 9, Android 4.4.

Next: , Previous: , Up: Functions in <uchar.h>   [Contents][Index]

10.68.3 c32rtomb

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.30.1.6.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/c32rtomb.html

Gnulib module: c32rtomb

Portability problems fixed by Gnulib:

  • This function is missing on most non-glibc platforms: glibc 2.15, macOS 14, FreeBSD 6.4, NetBSD 10.0, OpenBSD 7.3, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.4.x, mingw, MSVC 9, Android 4.4.
  • This function returns 0 when the first argument is NULL in some locales on some platforms: AIX 7.2.

Portability problems not fixed by Gnulib:

  • This function is only defined as an inline function on some platforms: Haiku 2020.

Next: , Previous: , Up: Functions in <uchar.h>   [Contents][Index]

10.68.4 mbrtoc8

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on most platforms: glibc 2.35, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <uchar.h>   [Contents][Index]

10.68.5 mbrtoc16

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.30.1.3.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mbrtoc16.html

Gnulib module: mbrtoc16

Portability problems fixed by Gnulib:

  • This function is missing on most non-glibc platforms: glibc 2.15, macOS 14, FreeBSD 6.4, NetBSD 10.0, OpenBSD 7.3, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.4.x, mingw, MSVC 9, Android 4.4.
  • This function may crash when the first argument is NULL on some platforms: glibc 2.36.
  • In the C or POSIX locales, this function can return (size_t) -1 and set errno to EILSEQ: glibc 2.36.
  • This function returns 0 instead of (size_t) -2 when the input is empty: glibc 2.19, Android 11.
  • This function returns the total number of bytes that make up the multibyte character, not the number of bytes that were needed to complete the multibyte character, on some platforms: mingw.
  • This function returns (size_t) -3 instead of a byte count when it has stored a high surrogate, and returns a byte count instead of (size_t) -3 when it has stored a low surrogate, on some platforms: Android.
  • This function does not recognize multibyte sequences that mbrtowc recognizes on some platforms: FreeBSD 13.2, Solaris 11.4, MSVC 14.

Portability problems not fixed by Gnulib:

  • After mbrtoc16 returns a char16_t value, mbsinit cannot be used to determine whether the function is ready to return another char16_t value. To do so, instead call mbrtoc16 again, with an appropriately incremented const char * argument and an appropriately decremented size_t argument.

Previous: , Up: Functions in <uchar.h>   [Contents][Index]

10.68.6 mbrtoc32

ISO C23 specification:
https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3220.pdf section 7.30.1.5.

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mbrtoc32.html

Gnulib module: mbrtoc32 or mbrtoc32-regular

Portability problems fixed by either Gnulib module mbrtoc32 or mbrtoc32-regular:

  • This function is missing on most non-glibc platforms: glibc 2.15, macOS 14, FreeBSD 6.4, NetBSD 10.0, OpenBSD 7.3, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 3.4.x, mingw, MSVC 9, Android 4.4.
  • In the C or POSIX locales, this function can return (size_t) -1 and set errno to EILSEQ: glibc 2.35.
  • This function returns 0 instead of (size_t) -2 when the input is empty: glibc 2.19, mingw, Android 11, Haiku.
  • This function does not recognize multibyte sequences that mbrtowc recognizes on some platforms: FreeBSD 13.2, Solaris 11.4, mingw, MSVC 14.
  • This function does not work when it’s fed the input bytes one-by-one on some platforms: Cygwin 3.5.3.

Portability problems fixed by Gnulib module mbrtoc32-regular:

  • This function can map some multibyte characters to a sequence of two or more Unicode characters, and may thus return (size_t) -3. No known implementation currently (2023) behaves that way, but it may theoretically happen. With the mbrtoc32-regular module, you have the guarantee that the Gnulib-provided mbrtoc32 function maps each multibyte character to exactly one Unicode character and thus never returns (size_t) -3.
  • This function behaves incorrectly when converting precomposed characters from the BIG5-HKSCS encoding: glibc 2.36.

Portability problems not fixed by Gnulib:

  • This function is only defined as an inline function on some platforms: Haiku 2020.

Note: If you want the guarantee that the char32_t values returned by this function are Unicode code points, you also need to request the uchar-h-c23 module.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.69 Functions in <unistd.h>

Next: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.1 _exit

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/_exit.html

Gnulib module: unistd-h

Portability problems fixed by Gnulib:

  • This function is declared in a different header file (namely, <stdlib.h>) on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.2 _Fork

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/_Fork.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Creating-a-Process.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.33, macOS 14, FreeBSD 13.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android API level 34.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.3 access

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/access.html

Gnulib module: access

Portability problems fixed by Gnulib:

  • This function does not support the X_OK mode on some platforms: MSVC 14.
  • This function does not reject trailing slashes on symlinks to non-directories on some platforms: Mac OS X 10.5.

Portability problems not fixed by Gnulib:

  • This function uses the effective id instead of the real id on some platforms: Cygwin 1.5.x.

Other problems of this function:

  • There is an inherent race between calling this function and performing some action based on the results; you should think twice before trusting this function, especially in a set-uid or set-gid program.
  • This function does not have an option for not following symbolic links (like stat versus lstat). If you need this option, use the Gnulib module faccessat with the AT_EACCESS flag.
  • On Solaris, for the root user, any file is X_OK even if the file does not have the x permission bit set.
  • On native Windows, files whose basename does not contain a ‘.’ cannot be executed through execlp or execvp. Nevertheless, this function may return true for such files.
  • On Windows, different facilities for executing a program have different ways of finding an executable file, by trying various suffixes. For example, execlp and execvp search for files with the suffixes .com, .exe, .bat, .cmd, when the file with the given file name does not exist. Whereas cmd.exe searches according to the PATHEXT environment variable. This function does not perform any search; it merely looks at the file with the given file name.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.4 alarm

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/alarm.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function has no impact if SIGALRM is inherited as ignored; programs should use signal (SIGALRM, SIG_DFL) if it is important to ensure the alarm will fire.
  • Use of this function in multi-threaded programs is not advised.
  • This function is missing on some platforms: mingw (2011), MSVC 14.
  • This function is conditionally declared in the non-standard <io.h> header on some platforms: mingw (2012 or newer).

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.5 chdir

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/chdir.html

Gnulib module: chdir

Portability problems fixed by Gnulib:

  • This function is declared in different header files (namely, <io.h> or <direct.h>) on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.6 chown

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/chown.html

Gnulib module: chown

Portability problems fixed by Gnulib:

  • Some platforms fail to detect trailing slash on non-directories, as in chown("link-to-file/",uid,gid): macOS 14, FreeBSD 7.2, AIX 7.3.1, Solaris 9.
  • Some platforms fail to update the change time when at least one argument was not −1, but no ownership changes resulted: OpenBSD 7.7, Cygwin 2.9.0.
  • When passed an argument of −1, some implementations really set the owner user/group id of the file to this value, rather than leaving that id of the file alone: some very old platforms.
  • When applied to a symbolic link, some implementations don’t dereference the symlink, i.e. they behave like lchown: some very old platforms.
  • This function is missing on some platforms; however, the replacement always fails with ENOSYS: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • This function sometimes fails with EACCES when the failure is due to lack of appropriate privileges (EPERM), not to search permission denied on the file name prefix (EACCES): Linux kernel 5.15 with glibc 2.35 and a CIFS v1 file system (see https://bugs.gnu.org/65599).

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.7 close

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/close.html

Gnulib module: close

Portability problems fixed by Gnulib:

  • This function is declared in a different header file (namely, <io.h>) on some platforms: MSVC 14.
  • This function crashes when invoked with invalid arguments on some platforms: MSVC 14.
  • On Windows platforms (excluding Cygwin), socket and accept do not return file descriptors that can be closed by close. Instead, closesocket must be used.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.8 confstr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/confstr.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.9 crypt

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/crypt.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.34, FreeBSD 6.0, NetBSD 5.0, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function is not declared in <unistd.h> (without -D_GNU_SOURCE) on some platforms: glibc (at least 2.11–2.13).

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.10 dup

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dup.html

Gnulib module: dup

Portability problems fixed by Gnulib:

  • This function is declared in a different header file (namely, <io.h>) on some platforms: MSVC 14.
  • This function crashes when invoked with invalid arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.11 dup2

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dup2.html

Gnulib module: dup2

Portability problems fixed by Gnulib:

  • This function is declared in a different header file (namely, <io.h>) on some platforms: MSVC 14.
  • This function always returns 0 for success on some platforms: mingw, MSVC 14.
  • This function can hang when duplicating an fd to itself on some platforms: mingw, MSVC 14.
  • This function crashes when invoked with invalid arguments on some platforms: Cygwin 1.7.17, MSVC 14.
  • This function crashes when invoked with valid arguments on some platforms: Cygwin 1.7.25.
  • This function fails with EINVAL when duplicating an fd to itself: Android.
  • This function resets the FD_CLOEXEC flag when duplicating an fd to itself on some platforms: Haiku.
  • This function returns 0 for dup2 (1, 1) on some platforms: Cygwin 1.5.x.
  • This function may return -EBADF instead of -1 on some platforms: Linux releases between July 2008 and May 2009 (versions 2.6.27 to 2.6.29).
  • This function returns EMFILE instead of EBADF for large targets, which interferes with using dup2(fd,fd)==fd) as the minimal EBADF filter: AIX 7.1, FreeBSD 6.1, Cygwin 1.5.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.12 dup3

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/dup3.html

Documentation:
man dup3

Gnulib module: dup3

Portability problems fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.8, macOS 14, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.1, mingw, MSVC 14, Android 4.4.
  • This function can crash on some platforms: Cygwin 1.7.25.
  • This function mistakenly succeeds when given two equal file descriptors on some platforms: NetBSD 10.0, Haiku.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.13 encrypt

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/encrypt.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function is not declared in <unistd.h> (without -D_GNU_SOURCE) on some platforms: glibc (at least 2.11–2.13).
  • POSIX.1-2024 says this function is obsolescent and it is planned to be removed in a future version.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.14 environ

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/environ.html

Gnulib module: environ

Portability problems fixed by Gnulib:

  • POSIX does not require this variable to be declared, and it is indeed not declared on some platforms: macOS 14, FreeBSD 14.0, NetBSD 5.0, OpenBSD 3.8, Solaris 11.4.
  • On macOS, this variable is not declared. Up to Mac OS X 10.4, one can use 
    extern char **environ;

    to get the variable declared. This does not work any more, however, in shared libraries on macOS 10.5. Here is a workaround: Instead, one can use 

    #include <crt_externs.h>
#define environ (*_NSGetEnviron())

    This works at all versions of macOS.

  • On Cygwin in 64-bit mode, references to this variable cause a link error when the option -Wl,--disable-auto-import is in use.

Portability problems not fixed by Gnulib:

  • The address of this variable is not a compile-time constant on some platforms: mingw.
  • Assigning NULL to environ to clear all variables is not portable; better is to assign environ to one-element array containing a NULL pointer. That said, an empty environment is not portable either, as some systems may require particular environment variables (such as PATH) to be present in order to operate consistently.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.15 execl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/execl.html

Gnulib module: execl

Portability problems fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not pass command-line arguments correctly if they contain space, tab, backslash, or double-quote characters.
  • On Windows platforms (excluding Cygwin), this function spawns an asynchronous child process and then exits the current process immediately. As a consequence, the parent of the current process 1. may incorrectly proceed as if its child had exited, and 2. will never see the child’s exit status.
  • On Windows platforms (excluding Cygwin), the return type of this function is intptr_t, not int.

Note: The Gnulib replacement for this function is not async-safe, that is, it must not be invoked from a signal handler.

Portability problems not fixed by Gnulib:

  • On some platforms, a script without executable permission is still run: Cygwin 1.5.x.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.16 execle

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/execle.html

Gnulib module: execle

Portability problems fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not pass command-line arguments correctly if they contain space, tab, backslash, or double-quote characters.
  • On Windows platforms (excluding Cygwin), this function spawns an asynchronous child process and then exits the current process immediately. As a consequence, the parent of the current process 1. may incorrectly proceed as if its child had exited, and 2. will never see the child’s exit status.
  • On Windows platforms (excluding Cygwin), the return type of this function is intptr_t, not int.

Note: The Gnulib replacement for this function is not async-safe, that is, it must not be invoked from a signal handler.

Portability problems not fixed by Gnulib:

  • On some platforms, a script without executable permission is still run: Cygwin 1.5.x.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.17 execlp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/execlp.html

Gnulib module: execlp

Portability problems fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not pass command-line arguments correctly if they contain space, tab, backslash, or double-quote characters.
  • On Windows platforms (excluding Cygwin), this function spawns an asynchronous child process and then exits the current process immediately. As a consequence, the parent of the current process 1. may incorrectly proceed as if its child had exited, and 2. will never see the child’s exit status.
  • On Windows platforms (excluding Cygwin), the return type of this function is intptr_t, not int.

Portability problems not fixed by Gnulib:

  • On some platforms, a script without executable permission is still run: Cygwin 1.5.x.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.18 execv

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/execv.html

Gnulib module: execv

Portability problems fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not pass command-line arguments correctly if they contain space, tab, backslash, or double-quote characters.
  • On Windows platforms (excluding Cygwin), this function spawns an asynchronous child process and then exits the current process immediately. As a consequence, the parent of the current process 1. may incorrectly proceed as if its child had exited, and 2. will never see the child’s exit status.
  • On Windows platforms (excluding Cygwin), the return type of this function is intptr_t, not int.

Note: The Gnulib replacement for this function is not async-safe, that is, it must not be invoked from a signal handler.

Portability problems not fixed by Gnulib:

  • On some platforms, a script without executable permission is still run: Cygwin 1.5.x.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.19 execve

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/execve.html

Gnulib module: execve

Portability problems fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not pass command-line arguments correctly if they contain space, tab, backslash, or double-quote characters.
  • On Windows platforms (excluding Cygwin), this function spawns an asynchronous child process and then exits the current process immediately. As a consequence, the parent of the current process 1. may incorrectly proceed as if its child had exited, and 2. will never see the child’s exit status.
  • On Windows platforms (excluding Cygwin), the return type of this function is intptr_t, not int.

Note: The Gnulib replacement for this function is not async-safe, that is, it must not be invoked from a signal handler.

Portability problems not fixed by Gnulib:

  • On some platforms, a script without executable permission is still run: Cygwin 1.5.x.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.20 execvp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/execvp.html

Gnulib module: execvp

Portability problems fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), this function does not pass command-line arguments correctly if they contain space, tab, backslash, or double-quote characters.
  • On Windows platforms (excluding Cygwin), this function spawns an asynchronous child process and then exits the current process immediately. As a consequence, the parent of the current process 1. may incorrectly proceed as if its child had exited, and 2. will never see the child’s exit status.
  • On Windows platforms (excluding Cygwin), the return type of this function is intptr_t, not int.

Portability problems not fixed by Gnulib:

  • On some platforms, a script without executable permission is still run: Cygwin 1.5.x.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.21 faccessat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/faccessat.html

Gnulib module: faccessat

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 10.9, FreeBSD 7.4, NetBSD 6.1.5, OpenBSD 4.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 4.0.4.
  • On some platforms, faccessat (dfd, "file/", amode, flag) succeeds instead of failing when file is not a directory. macOS 14.

Portability problems not fixed by Gnulib:

  • The replacement does not always take ACLs into account.
  • The replacement is not safe to be used in libraries.
  • The replacement is not thread-safe.
  • The replacement does not support the AT_SYMLINK_NOFOLLOW flag, which is supported by GNU faccessat.
  • On some platforms, faccessat can mishandle AT_EACCESS after a process starts as root and then becomes non-root: GNU/Linux with glibc 2.32.
  • This function does not support AT_EMPTY_PATH: Linux kernel 2.6.38.
  • When AT_EMPTY_PATH is used, this function does not allow the file name to be a null pointer: glibc 2.41, Linux kernel 6.10, Cygwin 3.6, FreeBSD 15.1.

Other problems of this function:

  • There is an inherent race between calling this function and performing some action based on the results; you should think twice before trusting this function, especially in a set-uid or set-gid program.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.22 fchdir

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fchdir.html

Gnulib module: fchdir

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14. But the replacement function is not safe to be used in libraries and is not thread-safe.

Portability problems not fixed by Gnulib:

  • This function fails if the file descriptor was opened with O_PATH: Linux kernel 3.4.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.23 fchown

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fchown.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • This function sometimes fails with EACCES when the failure is due to lack of appropriate privileges (EPERM), not to search permission denied on the file name prefix (EACCES): Linux kernel 5.15 with glibc 2.35 and a CIFS v1 file system (see https://bugs.gnu.org/65599).

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.24 fchownat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fchownat.html

Gnulib module: fchownat

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.5.x, mingw, MSVC 14. But the replacement function is not safe to be used in libraries and is not thread-safe. Also, the replacement may fail to change symlinks if lchown is unsupported, or fail altogether if chown is unsupported.
  • This function is declared in <sys/stat.h>, not in <unistd.h>, on some platforms: Android 4.3.
  • Some platforms fail to detect trailing slash on non-directories, as in fchown(dir,"link-to-file/",uid,gid,flag): Solaris 9.
  • Some platforms fail to update the change time when at least one argument was not −1, but no ownership changes resulted: OpenBSD 7.7.
  • Some platforms mistakenly dereference symlinks when using AT_SYMLINK_NOFOLLOW: Linux kernel 2.6.17.
  • This function does not fail for an empty filename on some platforms: Linux with glibc < 2.11.

Portability problems not fixed by Gnulib:

  • When AT_EMPTY_PATH is used, this function does not allow the file name to be a null pointer: Linux kernel 6.10, Cygwin 3.6, FreeBSD 15.1.
  • This function sometimes fails with EACCES when the failure is due to lack of appropriate privileges (EPERM), not to search permission denied on the file name prefix (EACCES): Linux kernel 5.15 with glibc 2.35 and a CIFS v1 file system (see https://bugs.gnu.org/65599).

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.25 fdatasync

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fdatasync.html

Gnulib module: fdatasync

Portability problems fixed by Gnulib:

  • This function is present but not declared on some platforms: Mac OS X 10.7.
  • This function is missing on some platforms: Mac OS X 10.5, FreeBSD 11.0, OpenBSD 3.8, Minix 3.1.8, mingw, MSVC 14, Android 2.2.

Portability problems not fixed by Gnulib:

  • If the argument is a file descriptor that lacks write access, such as a directory file descriptor, this function fails with EBADF on some platforms: AIX 7.3, Cygwin 3.6.x.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.26 fexecve

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fexecve.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11 2010-11, Cygwin 1.5.x, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.27 fork

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fork.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • On some platforms, fork followed by a call of the exec family (execl, execlp, execle, execv, execvp, or execve) is less efficient than vfork followed by the same call. vfork is a variant of fork that has been introduced to optimize the fork/exec pattern.
  • On Windows platforms (excluding Cygwin), this function is not implemented; use _spawnvp instead.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.28 fpathconf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fpathconf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.29 fsync

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fsync.html

Gnulib module: fsync

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • If the argument is a file descriptor that lacks write access, such as a directory file descriptor, this function fails with EBADF on some platforms: AIX 7.3, Cygwin 3.6.x.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.30 ftruncate

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ftruncate.html

Gnulib module: ftruncate

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: MSVC 14.
  • On platforms where off_t is a 32-bit type, this function may not work correctly on files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.31 getcwd

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getcwd.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getcwd.html

Gnulib module: getcwd or getcwd-lgpl

Portability problems fixed by either Gnulib module getcwd or getcwd-lgpl:

  • This function is declared in different header files (namely, <io.h> or <direct.h>) on some platforms: mingw, MSVC 14.
  • On glibc and Solaris 11.4 platforms, getcwd (NULL, n) allocates memory for the result. On some other platforms, this call is not allowed.
  • On some platforms, the prototype for getcwd uses int instead of size_t for the size argument when using non-standard headers, and the declaration is missing from <unistd.h>: mingw, MSVC 14.
  • On some platforms, getcwd (buf, 0) crashes: MSVC 14.
  • On some platforms, getcwd (buf, 0) fails with ERANGE instead of the required EINVAL: mingw.

Portability problems fixed by Gnulib module getcwd:

  • This function does not handle long file names (greater than PATH_MAX) correctly on some platforms: glibc on Linux 2.4.20, musl libc 1.2.2/powerpc64le, macOS 13, FreeBSD 6.4, NetBSD 10.0, OpenBSD 7.9, AIX 7.1.

Portability problems not fixed by Gnulib:

  • When using getcwd(NULL, nonzero), some platforms, such as glibc or cygwin, allocate exactly nonzero bytes and fail with ERANGE if it was not big enough, while other platforms, such as FreeBSD, mingw, or MSVC 14, ignore the size argument and allocate whatever size is necessary. If this call succeeds, an application cannot portably access beyond the string length of the result.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.32 getegid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getegid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.33 getentropy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getentropy.html

Documentation:

Gnulib module: getentropy

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.24, Mac OS X 10.11, FreeBSD 11.0, NetBSD 9.3, OpenBSD 5.5, Minix 3.3, AIX 7.1, HP-UX 11.31, Solaris 11.0, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.
  • This function is declared in <sys/random.h>, not in <unistd.h>, on some platforms: macOS 14, Solaris 11.4, Android 9.0.

Portability problems not fixed by Gnulib:

Although this function is intended to produce random data, the data’s security properties may not be appropriate for your application. For example, identical “random” data streams might be produced by rebooted virtual machines. If this is of concern you may need to use additional techniques such as hedging.1

Related modules include getrandom, which has a more-flexible but more-complex API, and crypto/gc-random, which is likely a better match for code already using the other crypto APIs.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.34 geteuid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/geteuid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.35 getgid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getgid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.36 getgroups

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getgroups.html

Gnulib module: getgroups

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • On some platforms, this function fails to reject a negative count, even though that is less than the size that would be returned: macOS 14, FreeBSD 13.0.
  • On NeXTstep 3.2, getgroups (0, NULL) always fails. See macro ‘AC_FUNC_GETGROUPS’.
  • On very old systems, this function operated on an array of ‘int’, even though that was a different size than an array of ‘gid_t’.

Portability problems not fixed by Gnulib:

  • This function is unsafe to call between fork and exec if the parent process is multi-threaded.
  • It is unspecified whether the effective group id will be included in the returned list, nor whether the list will be sorted in any particular order. For that matter, some platforms include the effective group id twice, if it is also a member of the current supplemental group ids.

The Gnulib module mgetgroups provides a similar API.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.37 gethostid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/gethostid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.38 gethostname

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/gethostname.html

Gnulib module: gethostname

Portability problems fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <unistd.h> on some platforms: MSVC 14.
  • On mingw and MSVC 14, this function has a prototype that differs from that specified by POSIX, and it is defined only in the ws2_32 library.

Portability problems not fixed by Gnulib:

  • This function’s second argument type is int instead of size_t on some platforms: Solaris 10, Solaris 11 OmniOS.
  • If the given buffer is too small for the host name, some implementations fail with EINVAL, instead of returning a truncated host name.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.39 getlogin

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getlogin.html

Gnulib module: getlogin

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: older mingw, MSVC 14.
  • This function is not declared unless _POSIX is defined on some platforms: mingw.
  • This function returns the value of the LOGNAME environment variable and is therefore arbitrarily fakeable: musl libc 1.2.5.

Portability problems not fixed by Gnulib:

  • This function returns an empty string even when standard input is a tty on some platforms: HP-UX 11.11.
  • When there are several user names with the same user ID, this function may return, instead of the user name that logged in, another user name that has the same user ID, on some platforms: Linux and others.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.40 getlogin_r

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getlogin_r.html

Gnulib module: getlogin_r

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, Minix 3.1.8, mingw, MSVC 14, Android 8.1.
  • This function is not declared unless _REENTRANT is defined, on some platforms: HP-UX 11.
  • This function returns a truncated result, instead of failing with error code ERANGE, when the buffer is not large enough, on some platforms: macOS 14.
  • This function returns the value of the LOGNAME environment variable and is therefore arbitrarily fakeable: musl libc 1.2.5.

Portability problems not fixed by Gnulib:

  • This function has an incompatible declaration on some platforms: FreeBSD 12.0, MidnightBSD 2.0, Solaris 11.4 (when _POSIX_PTHREAD_SEMANTICS is not defined).
  • This function fails even when standard input is a tty on some platforms: HP-UX 11.11.
  • This function fails with error code EINVAL instead of ERANGE when the second argument is zero on some platforms: HP-UX 11.31.
  • This function fails with error code ENOMEM instead of ERANGE on some platforms: Haiku.
  • When there are several user names with the same user ID, this function may return, instead of the user name that logged in, another user name that has the same user ID, on some platforms: Linux and others.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.41 getopt

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getopt.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/libutil-getopt-3.html

Gnulib module: getopt-posix or getopt-gnu

The module getopt-gnu has support for “long options” and for “options that take optional arguments”. Compared to the API defined by POSIX, it adds a header file <getopt.h> and a function getopt_long.

Portability problems fixed by either Gnulib module getopt-posix or getopt-gnu:

  • This function is missing on some platforms: MSVC 14.
  • The value of optind after a missing required argument is wrong on some platforms: macOS 14, AIX 7.1, mingw.

Portability problems fixed by Gnulib module getopt-gnu:

  • The function getopt does not support the ‘+’ flag in the options string on some platforms: macOS 14, AIX 5.2, HP-UX 11, Solaris 11 2010-11.
  • The function getopt does not obey the combination of ‘+’ and ‘:’ flags in the options string on some platforms: glibc 2.11.
  • The function getopt does not obey the ‘-’ flag in the options string when POSIXLY_CORRECT is set on some platforms: Cygwin 1.7.0.
  • The function getopt does not support options with optional arguments on some platforms: macOS 14, OpenBSD 4.0, AIX 5.2, HP-UX 11, Solaris 11 2010-11, Cygwin 1.5.x.
  • The function getopt_long is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 9, MSVC 14.
  • The function getopt_long does not support abbreviated long options where all disambiguations are equivalent on some platforms: OpenBSD 5.0.
  • The function getopt_long_only is missing on some platforms: FreeBSD 5.2.1, NetBSD 10.0, AIX 5.1, HP-UX 11, Solaris 9, mingw, MSVC 14.
  • This function crashes if the option string includes W; on some platforms: glibc 2.14.

Portability problems not fixed by Gnulib:

  • The default behavior of the glibc implementation of getopt allows mixing option and non-option arguments on the command line in any order. Other implementations, such as the one in Cygwin, enforce strict POSIX compliance: they require that the option arguments precede the non-option arguments. This is something to watch out in your program’s testsuite.
  • The glibc implementation allows a complete reset of the environment, including re-checking for POSIXLY_CORRECT, by setting optind to 0. Several BSD implementations provide optreset, causing a reset by setting it non-zero, although it does not necessarily re-read POSIXLY_CORRECT. Solaris getopt does not support either reset method, but does not maintain state that needs the extra level of reset.
  • On some platforms, this function does not set the stream error indicator on attempts to write to a read-only stream: glibc 2.13, Cygwin 1.7.9.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.42 getpgid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getpgid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.43 getpgrp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getpgrp.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.44 getpid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getpid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.45 getppid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getppid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.46 getresgid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getresgid.html

Documentation:
man getresgid

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, Minix 3.1.8, AIX 5.1, HP-UX 11.00, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.47 getresuid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getresuid.html

Documentation:
man getresuid

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, Minix 3.1.8, AIX 5.1, HP-UX 11.00, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.48 getsid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getsid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 4.1.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.49 getuid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getuid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.50 isatty

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/isatty.html

Gnulib module: isatty

Portability problems fixed by Gnulib:

  • This function is declared in a different header file (namely, <io.h>) on some platforms: MSVC 14.
  • On native Windows, this function also returns true for character devices such as NUL.
  • On native Windows, this function returns false for Cygwin consoles.
  • This function crashes when invoked with invalid arguments on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.51 lchown

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lchown.html

Gnulib module: lchown

Portability problems fixed by Gnulib:

  • This function is missing on some platforms; however, the replacement fails with ENOSYS: mingw, MSVC 14.
  • This function is missing on some platforms; however, the replacement fails on symlinks: Minix 3.2.1.
  • Some platforms fail to detect trailing slash on non-directories, as in lchown("link-to-file/",uid,gid): FreeBSD 7.2, Solaris 9.
  • Some platforms fail to update the change time when at least one argument was not −1, but no ownership changes resulted: OpenBSD 7.7.

Portability problems not fixed by Gnulib:

  • This function sometimes fails with EACCES when the failure is due to lack of appropriate privileges (EPERM), not to search permission denied on the file name prefix (EACCES): Linux kernel 5.15 with glibc 2.35 and a CIFS v1 file system (see https://bugs.gnu.org/65599).

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.53 linkat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/linkat.html

Gnulib module: linkat

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Mac OS X 10.9, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 4.4. But the replacement function is not safe to be used in libraries and is not thread-safe.
  • This function fails to directly hardlink symlinks on some platforms: Mac OS X 10.10.
  • This function fails to reject trailing slashes on non-directories on some platforms: macOS 14, AIX 7.1, Solaris 11.3.
  • This functions does not support AT_SYMLINK_FOLLOW on some platforms: Linux kernel 2.6.17.

Portability problems not fixed by Gnulib:

  • linkat (fd, "directory", fd, "symlink/" ...) sets errno to EINVAL instead of EEXIST or ENOTDIR on some platforms: GNU/Hurd with glibc 2.41.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.54 lockf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lockf.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, this function may not work correctly across the entire data range of files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.5.x, mingw, MSVC 14, Android 6.0.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.55 lseek

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/lseek.html

Gnulib module: lseek

Portability problems fixed by Gnulib:

  • On some platforms, lseek (fd, offset, SEEK_DATA) returns a value greater than offset even when offset addresses data: macOS 14.
  • This function is declared in a different header file (namely, <io.h>) on some platforms: MSVC 14.
  • On platforms where off_t is a 32-bit type, lseek does not work correctly with files 2 GiB and larger. See Large File Support.
  • This function mistakenly succeeds on pipes on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • POSIX does not specify which file descriptors support seeking and which don’t. In practice, regular files and block devices support seeking, and ttys, pipes, and most character devices don’t support it.
  • Some systems do not support SEEK_DATA and SEEK_HOLE: AIX, HP-UX, Microsoft Windows, NetBSD, OpenBSD, Cygwin 3.4.6.
  • Some systems have a buggy SEEK_DATA and SEEK_HOLE, and Gnulib works around the problem via #undef SEEK_DATA and #undef SEEK_HOLE: FreeBSD 13, macOS 12.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.56 nice

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/nice.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • In glibc before glibc 2.2.4, nice returned 0 upon success.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.57 optarg

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/optarg.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on some platforms: Mac OS X 10.5, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.58 opterr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/opterr.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on some platforms: MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.59 optind

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/optind.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on some platforms: MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.60 optopt

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/optopt.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on some platforms: Mac OS X 10.5, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.61 pathconf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pathconf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.62 pause

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pause.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.63 pipe

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pipe.html

Gnulib module: pipe-posix

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • This function crashes rather than failing with EMFILE if no resources are left on some platforms: Cygwin 1.7.9.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.64 pipe2

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pipe2.html

Documentation:
man pipe2

Gnulib module: pipe2

Portability problems fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.8, macOS 14, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.1, mingw, MSVC 14, Android 2.2. But the replacement function is not atomic; this matters in multi-threaded processes that spawn child processes.

Portability problems not fixed by Gnulib:

  • This function crashes rather than failing with EMFILE if no resources are left on some platforms: Cygwin 1.7.9.

Note: This function portably supports the O_NONBLOCK flag only if the gnulib module nonblocking is also used.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.65 posix_close

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/posix_close.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.42, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.66 pread

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pread.html

Gnulib module: pread

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • On platforms where off_t is a 32-bit type, this function may not work correctly on files 2 GiB and larger. See Large File Support.
  • This function returns zero instead of positive values when large file support is enabled on some platforms: HP-UX 11.11.
  • This function does not fail on pipes on some platforms: HP-UX 11.31.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.67 pwrite

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pwrite.html

Gnulib module: pwrite

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • On platforms where off_t is a 32-bit type, this function may not work correctly on files 2 GiB and larger. See Large File Support.
  • This function does not fail when an invalid (negative) offset is passed when large file support is enabled on some platforms: HP-UX 11.11.
  • This function uses an arbitrary offset instead of the off_t argument when large file support is enabled on some platforms: HP-UX 11.11.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.68 read

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/read.html

Gnulib module: read, stdio-h, nonblocking

Portability problems fixed by Gnulib module read:

  • This function is declared in a different header file (namely, <io.h>) on some platforms: mingw, MSVC 14.
  • This function crashes when invoked with invalid arguments on some platforms: MSVC 14.

Portability problems fixed by Gnulib module stdio-h, together with module nonblocking:

  • When reading from a non-blocking pipe whose buffer is empty, this function fails with errno being set to EINVAL instead of EAGAIN on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • This function may fail with error EINTR, even in programs that don’t install any signal handlers, on some platforms: macOS 14.

For handling EINTR, Gnulib provides a module ‘safe-read’ with a function safe_read.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.70 readlinkat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/readlinkat.html

Gnulib module: readlinkat

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Mac OS X 10.9, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 4.4. But the replacement function is not safe to be used in libraries and is not thread-safe.
  • Some platforms mistakenly succeed on file names ending in /: macOS 14.
  • On some platforms, this function returns int instead of ssize_t: AIX 7.1.
  • For the file name /dev/null, this function returns \Device\Null, which is unusable, on some platforms: Cygwin 3.3.6.

Portability problems mostly fixed by Gnulib:

  • On some platforms, this function fails and sets errno to ERANGE rather than returning truncated contents: AIX 7.2. The Gnulib replacement normally works as POSIX requires by returning the truncated contents. However, if the full link contents are unreasonably large (more than 4000 bytes) the replacement clears the entire buffer and returns the buffer size; although this is not a complete fix, it suffices for typical callers, which ignore the buffer contents anyway.

Portability problems not fixed by Gnulib:

  • Behaviors differ when this function is called on an empty file name. On most platforms, the function fails with error ENOENT. On Cygnus 3.4.6, the function fails with error EBADF instead. On GNU/Linux (kernel version 2.6.39 or later), when dirfd is nonnegative the function instead reads directly from dirfd, and this succeeds if dirfd corresponds to a symbolic link that was opened with O_PATH | O_NOFOLLOW.
  • This function always fails on platforms that don’t support symlinks: mingw, MSVC 14.
  • When this function is called on a directory: In the case of NFS mounted directories, Cygwin sets errno to ENOENT or EIO instead of EINVAL. To avoid this problem, check for a directory before calling this function.
  • When this function is called on a file that is not a symbolic link: Cygwin may set errno to EACCES instead of EINVAL.
  • When this function fails because it is called on an existing non-directory’s name concatenated to /, it sets errno to EINVAL: AIX 7.2.
  • Symlink contents do not always have a trailing null byte, and there is no indication if symlink contents were truncated if the return value matches the length. Furthermore, Linux sets errno to EINVAL if the requested length is zero. Use the gnulib module areadlink for improved ability to read symlink contents.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.71 rmdir

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/rmdir.html

Gnulib module: rmdir

Portability problems fixed by Gnulib:

  • This function is declared in different header files (namely, <io.h> or <direct.h>) on some platforms: mingw, MSVC 14.
  • This function mistakenly removes a directory with rmdir("dir/./") on some platforms: Cygwin 1.5.x.
  • This function fails with EINVAL instead of the expected ENOTDIR for rmdir("file/") on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • When rmdir fails because the specified directory is not empty, the errno value is system dependent.
  • POSIX requires that rmdir("link-to-empty/") remove empty and leave link-to-empty as a dangling symlink. This is counter-intuitive, so some systems fail with ENOTDIR instead: glibc

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.72 setegid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setegid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11.23, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.73 seteuid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/seteuid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11.23, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.74 setgid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setgid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.75 setpgid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setpgid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.76 setregid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setregid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.77 setresgid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setresgid.html

Documentation:
man setresgid

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, Minix 3.1.8, AIX 5.1, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.78 setresuid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setresuid.html

Documentation:
man setresuid

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, Minix 3.1.8, AIX 5.1, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.79 setreuid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setreuid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.80 setsid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setsid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.81 setuid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setuid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.82 sleep

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sleep.html

Gnulib module: sleep

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw (2005 or newer), MSVC 14.
  • This function takes milliseconds as argument and returns void on some platforms: mingw (2005 and older).
  • This function cannot sleep longer than 49.7 days on some platforms: Cygwin 1.5.x.

Portability problems not fixed by Gnulib:

  • According to POSIX, the sleep function may interfere with the program’s use of the SIGALRM signal. On Linux, it doesn’t; on other platforms, it may.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.83 swab

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/swab.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Android 8.1.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.85 symlinkat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/symlinkat.html

Gnulib module: symlinkat

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 4.4. But the replacement function is not safe to be used in libraries and is not thread-safe.
  • Some platforms declare this function in stdio.h instead of unistd.h: Cygwin 1.7.1.
  • On some systems, symlinkat(value, fd, "name/") mistakenly creates a symlink: macOS 14, AIX 7.1.

Portability problems not fixed by Gnulib:

  • This function always fails with ENOSYS on platforms that don’t support symlinks: mingw, MSVC 14.
  • If the target is the empty string, this function can create an empty symbolic link instead of failing with ENOENT as GNU/Linux does: FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.8, Solaris 11.4. On Solaris, the empty symbolic link "" resolves like "." does; on the BSDs, resolution fails with ENOENT.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.86 sync

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sync.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.87 sysconf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/sysconf.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-sysconf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.88 tcgetpgrp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tcgetpgrp.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.89 tcsetpgrp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/tcsetpgrp.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.90 truncate

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/truncate.html

Gnulib module: truncate

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4 with AC_SYS_LARGEFILE in effect.
  • On platforms where off_t is a 32-bit type, this function is not applicable to arbitrary lengths for files 2 GiB and larger. See Large File Support.
  • This function does not fail when the file name argument ends in a slash and (without the slash) names a non-directory, on some platforms: AIX 7.2.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.91 ttyname

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ttyname.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • This function is just a stub that produces an error message on standard error on some platforms: Android 4.3.

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.92 ttyname_r

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ttyname_r.html

Gnulib module: ttyname_r

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, Minix 3.1.8, mingw, MSVC 14.
  • This function is not declared unless _REENTRANT is defined, on some platforms: HP-UX 11.
  • This function has an incompatible declaration on some platforms: Solaris 11.4 (when _POSIX_PTHREAD_SEMANTICS is not defined).
  • This function refuses to do anything when the output buffer is less than 128 bytes large, on some platforms: Solaris 11 2010-11.
  • This function is just a stub that produces an error message on standard error on some platforms: Android 4.3.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.94 unlinkat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/unlinkat.html

Gnulib module: unlinkat

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.5.x, mingw, MSVC 14. But the replacement function is not safe to be used in libraries and is not thread-safe.
  • This function is declared in <fcntl.h>, not in <unistd.h>, on some platforms: Cygwin 1.7.1, Android 4.3.
  • On Mac OS X 10.10, in a writable HFS mount, unlinkat(fd, "..", 0) succeeds without doing anything.
  • Some systems mistakenly succeed on unlinkat(fd,"file/",flag): GNU/Hurd, Solaris 9.

Portability problems not fixed by Gnulib:

  • When unlinkat(fd,name,AT_REMOVEDIR) fails because the specified directory is not empty, the errno value is system dependent.
  • POSIX requires that unlinkdir(fd,"link-to-empty/",AT_REMOVEDIR) remove empty and leave link-to-empty as a dangling symlink. This is counter-intuitive, so some systems fail with ENOTDIR instead: glibc
  • Some systems allow a superuser to unlink directories, even though this can cause file system corruption. The error given if a process is not permitted to unlink directories varies across implementations; it is not always the POSIX value of EPERM. Meanwhile, if a process has the ability to unlink directories, POSIX requires that unlinkat(fd,"symlink-to-dir/",0) remove dir and leave symlink-to-dir dangling; this behavior is counter-intuitive. The gnulib module unlinkdir can help determine whether code must be cautious of unlinking directories.
  • Removing an open file is non-portable: On Unix this allows the programs that have the file already open to continue working with it; the file’s storage is only freed when the no process has the file open any more. On Windows, the attempt to remove an open file fails.

Previous: , Up: Functions in <unistd.h>   [Contents][Index]

10.69.95 write

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/write.html

Gnulib module: write, nonblocking, sigpipe

Portability problems fixed by Gnulib module write:

  • This function is declared in a different header file (namely, <io.h>) on some platforms: mingw, MSVC 14.
  • This function crashes when invoked with invalid arguments on some platforms: MSVC 14.

Portability problems fixed by Gnulib module stdio-h, together with module nonblocking:

  • When writing to a non-blocking pipe whose buffer is full, this function fails with errno being set to ENOSPC instead of EAGAIN on some platforms: mingw, MSVC 14.
  • When writing to a non-blocking pipe on which no reader is currently waiting an amount of bytes that exceeds the pipe buffer’s size, then—even if the pipe’s buffer is empty—this function fails, instead of performing a partial write into the pipe buffer, on some platforms: mingw, MSVC 14.

Portability problems fixed by Gnulib module stdio-h, together with module sigpipe:

  • When writing to a pipe with no readers, this function fails with error EINVAL, instead of obeying the current SIGPIPE handler, on some platforms: mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • This function may fail with error EINTR, even in programs that don’t install any signal handlers, on some platforms: macOS 14.

For handling EINTR, Gnulib provides a module ‘safe-write’ with a function safe_write.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.70 Functions in <utmpx.h>

Next: , Up: Functions in <utmpx.h>   [Contents][Index]

10.70.1 endutxent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/endutxent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <utmpx.h>   [Contents][Index]

10.70.2 getutxent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getutxent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <utmpx.h>   [Contents][Index]

10.70.3 getutxid

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getutxid.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <utmpx.h>   [Contents][Index]

10.70.4 getutxline

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getutxline.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Functions in <utmpx.h>   [Contents][Index]

10.70.5 pututxline

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/pututxline.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Previous: , Up: Functions in <utmpx.h>   [Contents][Index]

10.70.6 setutxent

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/setutxent.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.71 Functions in <wchar.h>

Next: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.1 btowc

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/btowc.html

Gnulib module: btowc

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.00, mingw.
  • This function returns WEOF for a NUL argument on some platforms: Cygwin 1.7.2.
  • In the C or POSIX locales, this function is not consistent with Gnulib’s mbrtowc and can return WEOF: glibc 2.35, MirOS BSD #10.
  • In the C or POSIX locales, this function is not consistent with mbrtowc on some platforms: Cygwin 3.4.x, mingw with MSVCRT.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function btoc32, provided by Gnulib module btoc32, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.2 fgetwc

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fgetwc.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.5.x.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.3 fgetws

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fgetws.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.5.x.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.4 fputwc

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fputwc.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.5.x.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.5 fputws

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fputws.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.5.x.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.
  • On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.6 fwide

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fwide.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.00, Cygwin 1.5.x, MSVC 14.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.
  • fwide is not guaranteed to be able to change a file stream’s mode to a different mode than the current one.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.7 fwprintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fwprintf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11.00, Cygwin 1.5.x.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14, Haiku.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.
  • In the C or POSIX locales, the %c and %s conversions may fail on some platforms: glibc 2.35.
  • When formatting an integer with grouping flag, this function inserts thousands separators even in the "C" locale on some platforms: NetBSD 5.1.
  • On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.8 fwscanf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/fwscanf.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fwscanf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11.00, Cygwin 1.5.x.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.38, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.2, AIX 7.2, HP-UX 11, Solaris 11.4, Cygwin 2.9.0, mingw, MSVC 14.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.9 getwc

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getwc.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.5.x.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.10 getwchar

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/getwchar.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.5.x.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.11 mbrlen

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mbrlen.html

Gnulib module: mbrlen

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.00, mingw.
  • In the C or POSIX locales, this function can return (size_t) -1 and set errno to EILSEQ: glibc 2.35.
  • This function returns 0 instead of (size_t) -2 when the input is empty: glibc 2.19.
  • This function returns (size_t) -1 instead of (size_t) -2 when the input is empty: AIX 5.1.
  • This function does not put the state into non-initial state when parsing an incomplete multibyte character on some platforms: AIX 5.1.
  • This function returns the total number of bytes that make up the multibyte character, not the number of bytes that were needed to complete the multibyte character, on some platforms: HP-UX 11.11, Solaris 11 2010-11.
  • This function returns (size_t) -2 instead of (size_t) -1 for some invalid byte sequences on some platforms: NetBSD 10.
  • This function may not return 0 when parsing the NUL character on some platforms: Solaris 9.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.12 mbrtowc

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mbrtowc.html

Gnulib module: mbrtowc

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.00, mingw.
  • In the C or POSIX locales, this function can return (size_t) -1 and set errno to EILSEQ: glibc 2.35.
  • This function returns 0 instead of (size_t) -2 when the input is empty: glibc 2.19, mingw with UCRT, MSVC 14, Android 11.
  • This function returns (size_t) -1 instead of (size_t) -2 when the input is empty: AIX 7.2.
  • This function does not put the state into non-initial state when parsing an incomplete multibyte character on some platforms: AIX 7.2.
  • This function stores a wide character when parsing an incomplete multibyte character on some platforms: mingw with UCRT, MSVC 14.
  • This function returns the total number of bytes that make up the multibyte character, not the number of bytes that were needed to complete the multibyte character, on some platforms: HP-UX 11.11, Solaris 11 2010-11, mingw, MSVC 14.
  • This function returns (size_t) -2 instead of (size_t) -1 for some invalid byte sequences on some platforms: NetBSD 10.
  • This function may not return 0 when parsing the NUL character on some platforms: Solaris 9.

Portability problems not fixed by Gnulib:

  • In UTF-8 locales, this function may return wide characters up to 0x7FFFFFFF (that is, beyond 0x0010FFFF) on some platforms: glibc 2.34.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the ISO C11 function mbrtoc32, provided by Gnulib module mbrtoc32, operates on 32-bit wide characters and therefore does not have this limitation.
  • This function does not work with a copied mbstate_t on some platforms: Haiku.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.13 mbsinit

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mbsinit.html

Gnulib module: mbsinit

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.00, mingw with UCRT, MSVC 14.
  • This function always returns 1, even in multibyte locales, on some platforms: mingw.

Portability problems not fixed by Gnulib:

  • This function is not useful after calls to mbrtoc16 or mbrtoc8.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.14 mbsnrtowcs

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mbsnrtowcs.html

Gnulib module: mbsnrtowcs

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 11.3, Cygwin 1.5.x, mingw, MSVC 14, Android 4.4.
  • This function produces invalid wide characters on some platforms: Solaris 11.4.
  • In the C or POSIX locales, this function can return (size_t) -1 and set errno to EILSEQ: glibc 2.35.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function mbsnrtoc32s, provided by Gnulib module mbsnrtoc32s, operates on 32-bit wide characters and therefore does not have this limitation.
  • The specification is not clear about whether this function should update the conversion state when the first argument (the destination pointer) is NULL. The glibc, Mac OS X, FreeBSD implementations do update the state in this case. For portability, when passing a NULL destination argument, it is best to pass a pointer to a temporary copy of the conversion state.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.15 mbsrtowcs

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/mbsrtowcs.html

Gnulib module: mbsrtowcs

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.00, mingw.
  • This function does not work on some platforms: HP-UX 11, Solaris 11 2010-11.
  • In the C or POSIX locales, this function can return (size_t) -1 and set errno to EILSEQ: glibc 2.35.
  • This function does not work when the first argument is NULL on some platforms: mingw.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function mbsrtoc32s, provided by Gnulib module mbsrtoc32s, operates on 32-bit wide characters and therefore does not have this limitation.
  • The specification is not clear about whether this function should update the conversion state when the first argument (the destination pointer) is NULL. The glibc implementation does not update the state in this case; the macOS and FreeBSD implementations do. For portability, when passing a NULL destination argument, it is best to pass a pointer to a temporary copy of the conversion state.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.16 open_wmemstream

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/open_wmemstream.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, Mac OS X 10.5, FreeBSD 6.0, NetBSD 7.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.5.x, mingw, MSVC 14, Android 5.1.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.17 putwc

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/putwc.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.5.x.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.
  • On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.18 putwchar

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/putwchar.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.5.x.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.
  • On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.19 swprintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/swprintf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11.00, Cygwin 1.5.x, mingw with UCRT.
  • This function has a different signature on some platforms: MSVC 9.
  • This function is only defined as a macro on some platforms: MSVC 14.
  • This function does not support the ‘n’ directive on some platforms: glibc when used with _FORTIFY_SOURCE >= 2 (set by default on Ubuntu), macOS 14, OpenBSD, MSVC 14, Android.
  • This function sometimes returns a wrong value through the ‘n’ directive on some platforms: musl libc 1.2.3.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.
  • On Windows, this function does not take a buffer size as second argument.
  • This function produces wrong values for the ‘La’ directive on some platforms: glibc 2.15, Haiku, NetBSD 10.0.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • This function ignores the minimum field width in the ‘lc’ directive on some platforms: musl libc 1.2.3.
  • This function is broken when it produces output that contains null wide characters on some platforms: musl libc 1.2.3, macOS 14, FreeBSD 13.1, NetBSD 10.0, OpenBSD 7.2, AIX 7.2, mingw.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14, Haiku.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.
  • In the C or POSIX locales, the %c and %s conversions may fail on some platforms: glibc 2.35, musl libc 1.2.4, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.2, Cygwin 2.9.0.
  • The %lc directive may fail on some platforms: musl libc 1.2.4, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.2.
  • When formatting an integer with grouping flag, this function inserts thousands separators even in the "C" locale on some platforms: NetBSD 5.1.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.20 swscanf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/swscanf.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-swscanf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11.00, Cygwin 1.5.x.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.38, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.2, AIX 7.2, HP-UX 11, Solaris 11.4, Cygwin 2.9.0, mingw, MSVC 14.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.21 ungetwc

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/ungetwc.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.5.x.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.22 vfwprintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/vfwprintf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11.00, Cygwin 1.5.x.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14, Haiku.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.
  • In the C or POSIX locales, the %c and %s conversions may fail on some platforms: glibc 2.35.
  • When formatting an integer with grouping flag, this function inserts thousands separators even in the "C" locale on some platforms: NetBSD 5.1.
  • On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.23 vfwscanf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/vfwscanf.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-vfwscanf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11.23, Cygwin 1.5.x, Android 4.4.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.38, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.2, AIX 7.2, HP-UX 11, Solaris 11.4, Cygwin 2.9.0, mingw, MSVC 14.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.24 vswprintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/vswprintf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11.00, Cygwin 1.5.x.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.
  • On Windows, this function does not take a buffer size as second argument.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14, Haiku.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.
  • In the C or POSIX locales, the %c and %s conversions may fail on some platforms: glibc 2.35.
  • When formatting an integer with grouping flag, this function inserts thousands separators even in the "C" locale on some platforms: NetBSD 5.1.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.25 vswscanf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/vswscanf.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-vswscanf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11.23, Cygwin 1.5.x, MSVC 14, Android 4.4.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.38, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.2, AIX 7.2, HP-UX 11, Solaris 11.4, Cygwin 2.9.0, mingw, MSVC 14.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.26 vwprintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/vwprintf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11.00, Cygwin 1.7.
  • This function exists, but does not support wide arguments on some platforms: Cygwin 1.5.x.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14, Haiku.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.
  • In the C or POSIX locales, the %c and %s conversions may fail on some platforms: glibc 2.35.
  • When formatting an integer with grouping flag, this function inserts thousands separators even in the "C" locale on some platforms: NetBSD 5.1.
  • On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.27 vwscanf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/vwscanf.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-vwscanf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11.23, Cygwin 1.5.x, Android 4.4.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.38, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.2, AIX 7.2, HP-UX 11, Solaris 11.4, Cygwin 2.9.0, mingw, MSVC 14.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.28 wcpcpy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcpcpy.html

Gnulib module: wcpcpy

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14.
  • This function is not declared (without -D_GNU_SOURCE) on some platforms: glibc 2.13.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.29 wcpncpy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcpncpy.html

Gnulib module: wcpncpy

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14.
  • This function is not declared (without -D_GNU_SOURCE) on some platforms: glibc 2.13.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.30 wcrtomb

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcrtomb.html

Gnulib module: wcrtomb

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.00, mingw.
  • This function produces wrong characters in the C locale on some platforms: Android 4.3.
  • This function returns 0 when the first argument is NULL in some locales on some platforms: Solaris 11.3.
  • This function does not ignore the second argument when the first argument is NULL on some platforms: mingw with UCRT, MSVC 14.
  • This function fails to handle wide characters produced by mbrtowc on some platforms: Haiku.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the ISO C11 function c32rtomb, provided by Gnulib module c32rtomb, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.31 wcscasecmp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcscasecmp.html

Gnulib module: wcscasecmp

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.32 wcscasecmp_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcscasecmp_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: Mac OS X 10.5, FreeBSD 14.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 5.1.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.33 wcscat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcscat.html

Gnulib module: wcscat

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.34 wcschr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcschr.html

Gnulib module: wcschr

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.35 wcscmp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcscmp.html

Gnulib module: wcscmp

Portability problems fixed by Gnulib:

  • This function compares the wide characters as if they were unsigned, although wchar_t is signed, on some platforms: glibc 2.14.1 on x86 or x86_64, musl libc 1.2.3, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.2, Solaris 11.4.
  • This function may return a wrong result if the two arguments are of different length, on some platforms: glibc 2.37 on arm and arm64 CPUs, AIX 7.2 in 64-bit mode.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.36 wcscoll

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcscoll.html

Gnulib module: wcscoll

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.37 wcscoll_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcscoll_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.38 wcscpy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcscpy.html

Gnulib module: wcscpy

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Note: wcscpy (dst, src) is only safe to use when you can guarantee that there are at least wcslen (src) + 1 wide characters allocated at dst.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.39 wcscspn

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcscspn.html

Gnulib module: wcscspn

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.40 wcsdup

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcsdup.html

Gnulib module: wcsdup

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, HP-UX 11, Solaris 10, Cygwin 1.5.x.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.41 wcsftime

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcsftime.html

Gnulib module: wcsftime

Portability problems fixed by Gnulib:

  • On native Windows platforms (mingw, MSVC), this function works incorrectly when the environment variable TZ has been set by Cygwin.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, Cygwin 1.5.x.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.
  • Native Windows platforms (mingw, MSVC) support only a subset of time zones specified by POSIX. See tzset.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.42 wcslcat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcslcat.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Truncating-Strings.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.37, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.43 wcslcpy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcslcpy.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Truncating-Strings.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.37, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, mingw, MSVC 14.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.44 wcslen

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcslen.html

Gnulib module: wcslen

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.45 wcsncasecmp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcsncasecmp.html

Gnulib module: wcsncasecmp

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.46 wcsncasecmp_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcsncasecmp_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: Mac OS X 10.5, FreeBSD 14.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 5.1.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.47 wcsncat

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcsncat.html

Gnulib module: wcsncat

Portability problems fixed by Gnulib:

  • This function does not support zero-length operations on NULL pointers on some platforms: macOS 15, NetBSD 10.0, OpenBSD 7.6, Solaris 11.4, Cygwin 3.5.4.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.48 wcsncmp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcsncmp.html

Gnulib module: wcsncmp

Portability problems fixed by Gnulib:

  • This function compares the wide characters as if they were unsigned, although wchar_t is signed, on some platforms: glibc 2.14.1 on x86 or x86_64, musl libc 1.2.3, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.2, Solaris 11.4.
  • This function may return a wrong result if the two arguments are of different length, on some platforms: AIX 7.2 in 64-bit mode.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.49 wcsncpy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcsncpy.html

Gnulib module: wcsncpy

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Note: This function has no real use: It cannot be used for filling a fixed-size record with a wide string, before writing it to a file, because the wide string encoding is platform dependent and, on some platforms, also locale dependent. And this function is not appropriate for copying a wide string into a bounded memory area, because you have no guarantee that the result will be null-terminated. Even if you add the null character at the end yourself, this function is inefficient (as it spends time clearing unused memory) and will allow silent truncation to occur, which is not a good behavior for GNU programs.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.50 wcsnlen

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcsnlen.html

Gnulib module: wcsnlen

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 7.1, OpenBSD 7.5, Minix 3.1.8, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.51 wcsnrtombs

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcsnrtombs.html

Gnulib module: wcsnrtombs

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 11.3, Cygwin 1.5.x, mingw, MSVC 14, Android 4.4.
  • This function cannot consume valid sequences of wide characters on some platforms: Solaris 11.4.
  • In C++ mode, the system’s <wchar.h> defines std::wcsnrtombs but not ::wcsnrtombs on some platforms: Solaris 11 OpenIndiana.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32snrtombs, provided by Gnulib module c32snrtombs, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.52 wcspbrk

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcspbrk.html

Gnulib module: wcspbrk

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.53 wcsrchr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcsrchr.html

Gnulib module: wcsrchr

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.54 wcsrtombs

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcsrtombs.html

Gnulib module: wcsrtombs

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.00, mingw.
  • This function does not ignore the length argument if the destination argument is NULL on some platforms: mingw.
  • This function updates the source pointer also if the destination argument is NULL on some platforms: HP-UX 11.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32srtombs, provided by Gnulib module c32srtombs, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.55 wcsspn

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcsspn.html

Gnulib module: wcsspn

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.56 wcsstr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcsstr.html

Gnulib module: wcsstr or wcsstr-simple

Portability problems fixed by either Gnulib module wcsstr-simple or wcsstr:

  • This function is missing on some platforms: HP-UX 11.00.

Portability problems fixed by Gnulib module wcsstr:

  • This function has quadratic instead of linear worst-case complexity on some platforms: glibc 2.39, macOS 14, FreeBSD 13.1, NetBSD 10.0, OpenBSD 7.2, AIX 7.2, HP-UX 11, Solaris 11.4, Cygwin 2.9.0, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.57 wcstod

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcstod.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.5.x.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.58 wcstof

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcstof.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.5.x, MSVC 9, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.59 wcstok

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcstok.html

Gnulib module: wcstok

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Cygwin 1.5.x.
  • This function takes only two arguments on some platforms: mingw, older MSVC.
  • This function may use hidden state, ignoring the third argument, and thus exhibit a bug when two or more wcstok iteration loops are being performed in the same thread, on some platforms: HP-UX 11.31.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.60 wcstol

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcstol.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.5.x.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.61 wcstold

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcstold.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11, Solaris 9, Cygwin 1.7.x, MSVC 9, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.62 wcstoll

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcstoll.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.11, Solaris 9, Cygwin 1.5.x, MSVC 9, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.63 wcstoul

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcstoul.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.5.x.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.64 wcstoull

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcstoull.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.11, Solaris 9, Cygwin 1.5.x, MSVC 9, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.65 wcswidth

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcswidth.html

Gnulib module: wcswidth

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32swidth, provided by Gnulib module c32swidth, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.66 wcsxfrm

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcsxfrm.html

Gnulib module: wcsxfrm

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.5.x.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.67 wcsxfrm_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcsxfrm_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.68 wctob

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wctob.html

Gnulib module: wctob

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.00, mingw.
  • This function clobbers caller-owned registers on some platforms: Cygwin 1.7.5.
  • This function does not work on some platforms: Solaris 9.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32tob, provided by Gnulib module c32tob, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.69 wcwidth

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wcwidth.html

Gnulib module: wcwidth

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • This function is not declared (without -D_GNU_SOURCE) on some platforms: glibc 2.8.
  • This function handles combining characters in UTF-8 locales incorrectly on some platforms: macOS 14, NetBSD 9.3, OpenBSD 5.8, MidnightBSD 1.1.
  • This function returns 2 for characters with ambiguous east asian width, even in Western locales, on some platforms: Solaris 11.4.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32width, provided by Gnulib module c32width, operates on 32-bit wide characters and therefore does not have this limitation.
  • This function treats zero-width spaces like control characters on some platforms: AIX 7.2.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.70 wmemchr

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wmemchr.html

Gnulib module: wmemchr

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11.00, MSVC 14.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.71 wmemcmp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wmemcmp.html

Gnulib module: wmemcmp

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11.00, MSVC 14.
  • This function compares the wide characters as if they were unsigned, although wchar_t is signed, on some platforms: glibc 2.14.1 on x86 or x86_64, musl libc 1.2.3, NetBSD 10.0, OpenBSD 7.2, Solaris 11.4.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.72 wmemcpy

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wmemcpy.html

Gnulib module: wmemcpy

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11.00, MSVC 9.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.73 wmemmove

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wmemmove.html

Gnulib module: wmemmove

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11.00, MSVC 9.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.74 wmemset

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wmemset.html

Gnulib module: wmemset

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11.00, MSVC 9.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.75 wprintf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wprintf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11.00.
  • This function exists, but does not support wide arguments on some platforms: Cygwin 1.5.x.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14, Haiku.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.
  • In the C or POSIX locales, the %c and %s conversions may fail on some platforms: glibc 2.35.
  • When formatting an integer with grouping flag, this function inserts thousands separators even in the "C" locale on some platforms: NetBSD 5.1.
  • On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.

Previous: , Up: Functions in <wchar.h>   [Contents][Index]

10.71.76 wscanf

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wscanf.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-wscanf.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, HP-UX 11.00, Cygwin 1.5.x.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.38, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.2, AIX 7.2, HP-UX 11, Solaris 11.4, Cygwin 2.9.0, mingw, MSVC 14.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.72 Functions in <wctype.h>

Next: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.1 iswalnum

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswalnum.html

Gnulib module: wctype-h

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32isalnum, provided by Gnulib module c32isalnum, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.2 iswalnum_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswalnum_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.3 iswalpha

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswalpha.html

Gnulib module: wctype-h

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32isalpha, provided by Gnulib module c32isalpha, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.4 iswalpha_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswalpha_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.5 iswblank

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswblank.html

Gnulib module: iswblank

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Solaris 9, mingw, MSVC 9, Android 4.4.
  • This function is not declared (without -D_GNU_SOURCE) on some platforms: glibc 2.8.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32isblank, provided by Gnulib module c32isblank, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.6 iswblank_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswblank_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.7 iswcntrl

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswcntrl.html

Gnulib module: wctype-h

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32iscntrl, provided by Gnulib module c32iscntrl, operates on 32-bit wide characters and therefore does not have this limitation.
  • This function returns 0 for U+2028 (LINE SEPARATOR) and U+2029 (PARAGRAPH SEPARATOR) on some platforms: macOS 14.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.8 iswcntrl_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswcntrl_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.9 iswctype

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswctype.html

Gnulib module: iswctype

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.
  • This function is declared in <wchar.h>, not in <wctype.h>, on some platforms: HP-UX 11.00.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32_apply_type_test, provided by Gnulib module c32_apply_type_test, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.10 iswctype_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswctype_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.11 iswdigit

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswdigit.html

Gnulib module: iswdigit

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.
  • This function is not ISO C 99 compliant on some platforms: FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Solaris 11.4, mingw, MSVC 14, Haiku, Android.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32isdigit, provided by Gnulib module c32isdigit, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.12 iswdigit_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswdigit_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.13 iswgraph

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswgraph.html

Gnulib module: wctype-h

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32isgraph, provided by Gnulib module c32isgraph, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.14 iswgraph_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswgraph_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.15 iswlower

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswlower.html

Gnulib module: wctype-h

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32islower, provided by Gnulib module c32islower, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.16 iswlower_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswlower_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.17 iswprint

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswprint.html

Gnulib module: wctype-h

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.
  • This function returns true for the tab ('\t') character on some platforms: mingw.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32isprint, provided by Gnulib module c32isprint, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.18 iswprint_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswprint_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.19 iswpunct

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswpunct.html

Gnulib module: iswpunct

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.
  • This function is inconsistent with the ispunct function, because it returns false for the characters '$', '+', '<', '=', '>', '^', '`' , '|', '~' on some platforms: Android 11.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32ispunct, provided by Gnulib module c32ispunct, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.20 iswpunct_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswpunct_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.21 iswspace

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswspace.html

Gnulib module: wctype-h

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32isspace, provided by Gnulib module c32isspace, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.22 iswspace_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswspace_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.23 iswupper

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswupper.html

Gnulib module: wctype-h

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32isupper, provided by Gnulib module c32isupper, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.24 iswupper_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswupper_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.25 iswxdigit

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswxdigit.html

Gnulib module: iswxdigit

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.
  • This function is not ISO C 99 compliant on some platforms: FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Solaris 11.4, MSVC 14, Haiku, Android.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32isxdigit, provided by Gnulib module c32isxdigit, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.26 iswxdigit_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/iswxdigit_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.27 towctrans

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/towctrans.html

Gnulib module: towctrans

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.00, mingw, MSVC 9, Android 7.1.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32_apply_mapping, provided by Gnulib module c32_apply_mapping, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.28 towctrans_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/towctrans_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 7.1.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.29 towlower

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/towlower.html

Gnulib module: wctype-h

Portability problems fixed by Gnulib:

  • This function returns values of which the upper 16 bits are incorrect on some platforms: mingw.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32tolower, provided by Gnulib module c32tolower, operates on 32-bit wide characters and therefore does not have this limitation.
  • On native Windows, in an UTF-8 locale, this function does not even do the simple expected mappings, such as from 0x00C9 to 0x00E9.
  • This function returns wrong values even for the ASCII characters in a zh_CN.GB18030 locale on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.30 towlower_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/towlower_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.31 towupper

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/towupper.html

Gnulib module: wctype-h

Portability problems fixed by Gnulib:

  • This function returns values of which the upper 16 bits are incorrect on some platforms: mingw.
  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32toupper, provided by Gnulib module c32toupper, operates on 32-bit wide characters and therefore does not have this limitation.
  • On native Windows, in an UTF-8 locale, this function does not even do the simple expected mappings, such as from 0x00E9 to 0x00C9.
  • This function returns wrong values even for the ASCII characters in a zh_CN.GB18030 locale on some platforms: NetBSD 10.0.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.32 towupper_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/towupper_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.33 wctrans

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wctrans.html

Gnulib module: wctrans

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.00, mingw, MSVC 9, Android 7.1.
  • This function does not support the "tolower" and "toupper" mappings on some platforms: NetBSD 10.0. (It returns non-null values for the arguments "towlower" and "towupper", but with these values, the function towctrans always crashes.)

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32_get_mapping, provided by Gnulib module c32_get_mapping, operates on 32-bit wide characters and therefore does not have this limitation.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.34 wctrans_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wctrans_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 7.1.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.35 wctype

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wctype.html

Gnulib module: wctype

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, MSVC 9.
  • This function is declared in <wchar.h>, not in <wctype.h>, on some platforms: HP-UX 11.00.
  • This function does not support the "blank" character class on some platforms: mingw.
  • The object returned by this function for the "blank" character class is inconsistent with the iswblank and isblank functions on some platforms: MSVC 14.
  • The object returned by this function for the "punct" character class is inconsistent with the ispunct function on some platforms: Android 11.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters. However, the Gnulib function c32_get_type_test, provided by Gnulib module c32_get_type_test, operates on 32-bit wide characters and therefore does not have this limitation.

Previous: , Up: Functions in <wctype.h>   [Contents][Index]

10.72.36 wctype_l

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wctype_l.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Previous: , Up: ISO C and POSIX Function Substitutes   [Contents][Index]

10.73 Functions in <wordexp.h>

Next: , Up: Functions in <wordexp.h>   [Contents][Index]

10.73.1 wordexp

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wordexp.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.
  • On some platforms, this function does not set errno or the stream error indicator on attempts to write to a read-only stream: Cygwin 1.7.9.

Previous: , Up: Functions in <wordexp.h>   [Contents][Index]

10.73.2 wordfree

POSIX specification:
https://pubs.opengroup.org/onlinepubs/9799919799/functions/wordfree.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

11 Past POSIX Header File Substitutes

This chapter describes which header files specified by older versions of POSIX are substituted by Gnulib, which portability pitfalls are fixed by Gnulib, and which (known) portability problems are not worked around by Gnulib.

The notation “Gnulib module: —” means that Gnulib does not provide a module providing a substitute for the header file. When the list “Portability problems not fixed by Gnulib” is empty, such a module is not needed: No portability problems are known. Otherwise, it indicates that such a module would be useful but is not available: No one so far found this header file important enough to contribute a substitute for it. If you need this particular header file, you may write to <bug-gnulib at gnu dot org>.

Next: , Up: Past POSIX Header File Substitutes   [Contents][Index]

11.1 stropts.h

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/stropts.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin, mingw, MSVC 14, Android 9.0.
  • This header is removed in POSIX.1-2024.

Next: , Previous: , Up: Past POSIX Header File Substitutes   [Contents][Index]

11.2 sys/timeb.h

Removed in POSIX.1-2008. POSIX.1-2004 specification:
https://pubs.opengroup.org/onlinepubs/009695399/basedefs/sys/timeb.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: OpenBSD 7.9, Android 9.0.

Next: , Previous: , Up: Past POSIX Header File Substitutes   [Contents][Index]

11.3 trace.h

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/trace.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin, mingw, MSVC 14, Android 9.0.
  • This header is removed in POSIX.1-2024.

Next: , Previous: , Up: Past POSIX Header File Substitutes   [Contents][Index]

11.4 ucontext.h

Removed in POSIX.1-2008. POSIX.1-2004 specification:
https://pubs.opengroup.org/onlinepubs/009695399/basedefs/ucontext.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: OpenBSD 7.9, Cygwin 1.7.35, mingw, MSVC 14.

Next: , Previous: , Up: Past POSIX Header File Substitutes   [Contents][Index]

11.5 ulimit.h

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/ulimit.h.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, Cygwin, mingw, MSVC 14, Android 9.0.
  • This header is removed in POSIX.1-2024.

Previous: , Up: Past POSIX Header File Substitutes   [Contents][Index]

11.6 utime.h

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/utime.h.html

Gnulib module: utime-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

  • This header is removed in POSIX.1-2024.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

12 Past POSIX Function Substitutes

This chapter describes which functions and function-like macros specified by older versions of POSIX are substituted by Gnulib, which portability pitfalls are fixed by Gnulib, and which (known) portability problems are not worked around by Gnulib.

The notation “Gnulib module: —” means that Gnulib does not provide a module providing a substitute for the function. When the list “Portability problems not fixed by Gnulib” is empty, such a module is not needed: No portability problems are known. Otherwise, it indicates that such a module would be useful but is not available: No one so far found this function important enough to contribute a substitute for it. If you need this particular function, you may write to <bug-gnulib at gnu dot org>.

Next: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.1 _longjmp

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/_longjmp.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • This function is removed in POSIX.1-2024.

Note: Despite its being removed from POSIX, in 2024 on all systems which have _setjmp, it is the fastest way to save the registers but not the signal mask (up to 30 times faster than setjmp on some systems).

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.2 _setjmp

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/_setjmp.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is removed in POSIX.1-2024.

Note: Despite its being removed from POSIX, in 2024 on all systems which have _setjmp, it is the fastest way to save the registers but not the signal mask (up to 30 times faster than setjmp on some systems).

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.3 _tolower

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/_tolower.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, Minix 3.1.8, Android 4.4.
  • This function is removed in POSIX.1-2024. Use the function tolower instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.4 _toupper

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/_toupper.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, Minix 3.1.8, Android 4.4.
  • This function is removed in POSIX.1-2024. Use the function toupper instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.5 bcmp

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/bcmp.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 9.0.
  • This function is removed in POSIX.1-2008. Better use memcmp instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.6 bcopy

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/bcopy.html

Gnulib module: bcopy

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

  • This function is removed in POSIX.1-2008. Better use memcpy or memmove instead.
  • This module does not arrange to declare this function.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.7 bsd_signal

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/bsd_signal.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.3, FreeBSD 14.0, NetBSD 7.1, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.8 bzero

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/bzero.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 9.0.
  • This function is removed in POSIX.1-2008. Better use memset instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.9 ecvt

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/ecvt.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 14.0, NetBSD 10.0, Android 9.0.
  • This function is not declared on some platforms: Cygwin 2.9.
  • This function is removed in POSIX.1-2008. Better use sprintf instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.10 fattach

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/fattach.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.11 fcvt

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/fcvt.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 14.0, NetBSD 10.0, Android 9.0.
  • This function is not declared on some platforms: Cygwin 2.9.
  • This function is removed in POSIX.1-2008. Better use sprintf instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.12 fdetach

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/fdetach.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.13 ftime

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/ftime.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.3, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Android 9.0.
  • This function is not declared on some platforms: Android 13.
  • On native Windows platforms (mingw, MSVC), this function works incorrectly when the environment variable TZ has been set by Cygwin.
  • This function is removed in POSIX.1-2008. Better use clock_gettime instead, and use ftime only as a fallback for portability to Windows platforms.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.14 ftw

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/ftw.html

Gnulib module: —

Portability problems fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, this function may not work correctly on files 2 GiB and larger. See Large File Support.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 3.0, Minix 3.1.8, mingw, MSVC 14, Android 4.1.
  • This function is removed in POSIX.1-2024. Use the Gnulib module fts instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.15 gcvt

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/gcvt.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.3, FreeBSD 14.0, NetBSD 10.0, Android 9.0.
  • This function is not declared on some platforms: Cygwin 2.9.
  • This function is removed in POSIX.1-2008. Better use sprintf instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.16 getcontext

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/getcontext.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.

Note: A third-party implementation is available at https://github.com/kaniini/libucontext/.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.17 gethostbyaddr

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/gethostbyaddr.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <netdb.h> on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.18 gethostbyname

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/gethostbyname.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is declared in <winsock2.h> instead of <netdb.h> on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.19 getitimer

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/getitimer.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • This function is removed in POSIX.1-2024. Use the function timer_gettime instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.20 getmsg

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/getmsg.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.21 getpmsg

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/getpmsg.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.22 gets

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/gets.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is removed in POSIX.1-2024. Use the function fgets instead.
  • This function should never be used, because it can overflow any given buffer.
  • This function is missing on some platforms: OpenBSD 7.9, Solaris 11.4.
  • When reading from a non-blocking pipe whose buffer is empty, this function fails with errno being set to EINVAL instead of EAGAIN on some platforms: mingw, MSVC 14.
  • On Windows platforms (excluding Cygwin), this function does not set errno upon failure.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.23 gettimeofday

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/gettimeofday.html

Gnulib module: gettimeofday

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: MSVC 14.
  • This function is declared with a nonstandard function prototype (only one argument, or “...” after the first argument) on some platforms.
  • On some platforms, the second argument has type struct timezone* rather than void *, making it an error to redeclare the function with the POSIX signature: glibc. However, rather than penalize these systems with a replacement function, gnulib defines GETTIMEOFDAY_TIMEZONE to the appropriate type for use in avoiding a compiler warning if assigning gettimeofday to a function pointer.
  • This function has only a precision of 15.6 milliseconds on some platforms: mingw.

Portability problems not fixed by Gnulib:

  • Behavior is non-portable if the second argument to gettimeofday is not NULL.
  • This function is removed in POSIX.1-2024. Use the Gnulib module gettime or timespec_get instead. (POSIX recommends to use the function clock_gettime, but there is no corresponding Gnulib module for it yet.)

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.24 getwd

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/getwd.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 9.0.
  • The size of the buffer required for this function is not a compile-time constant. Also, the function truncates a result that would be larger than the minimum buffer size. For these reasons, this function is removed in POSIX.1-2008. Better use the getcwd function instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.25 h_errno

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/h_errno.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.34, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.26 index

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/index.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 9.0.
  • This function is not declared on some platforms: Android 13.
  • This function is removed in POSIX.1-2008. Better use strchr instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.27 ioctl

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/ioctl.html

LSB specification:

Gnulib module: ioctl

Portability problems fixed by Gnulib:

  • On Windows platforms (excluding Cygwin), ioctl is called ioctlsocket, and error codes from this function are not placed in errno, and WSAGetLastError must be used instead.
  • The second parameter is of type unsigned long rather than int on some platforms: glibc 2.26, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Haiku 2017.

Portability problems not fixed by Gnulib:

  • Most ioctl requests are platform and hardware specific.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.28 isascii

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/isascii.html

Gnulib module: —

Portability problems not fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.
  • This function is removed in POSIX.1-2024.

Note: This function’s behaviour depends on the locale, but requires special handling for the multibyte characters that occur in strings in locales with MB_CUR_MAX > 1 (this includes all the common UTF-8 locales). There are two alternative APIs:

c_isascii

This function operates in a locale independent way and returns true only for ASCII characters. It is provided by the Gnulib module ‘c-ctype’.

mb_isascii

This function operates in a locale dependent way, on multibyte characters. It is provided by the Gnulib module ‘mbchar’.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.29 isastream

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/isastream.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.30 makecontext

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/makecontext.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.

Note: A third-party implementation is available at https://github.com/kaniini/libucontext/.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.31 mktemp

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/mktemp.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is not appropriate for creating temporary files. (It has security risks.) Therefore it is removed in POSIX.1-2008. Better use mkstemp instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.32 posix_trace_attr_destroy

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_destroy.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.33 posix_trace_attr_getclockres

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_getclockres.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.34 posix_trace_attr_getcreatetime

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_getcreatetime.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.35 posix_trace_attr_getgenversion

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_getgenversion.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.36 posix_trace_attr_getinherited

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_getinherited.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.37 posix_trace_attr_getlogfullpolicy

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_getlogfullpolicy.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.38 posix_trace_attr_getlogsize

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_getlogsize.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.39 posix_trace_attr_getmaxdatasize

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_getmaxdatasize.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.40 posix_trace_attr_getmaxsystemeventsize

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_getmaxsystemeventsize.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.41 posix_trace_attr_getmaxusereventsize

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_getmaxusereventsize.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.42 posix_trace_attr_getname

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_getname.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.43 posix_trace_attr_getstreamfullpolicy

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_getstreamfullpolicy.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.44 posix_trace_attr_getstreamsize

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_getstreamsize.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.45 posix_trace_attr_init

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_init.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.46 posix_trace_attr_setinherited

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_setinherited.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.47 posix_trace_attr_setlogfullpolicy

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_setlogfullpolicy.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.48 posix_trace_attr_setlogsize

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_setlogsize.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.49 posix_trace_attr_setmaxdatasize

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_setmaxdatasize.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.50 posix_trace_attr_setname

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_setname.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.51 posix_trace_attr_setstreamfullpolicy

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_setstreamfullpolicy.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.52 posix_trace_attr_setstreamsize

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_attr_setstreamsize.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.53 posix_trace_clear

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_clear.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.54 posix_trace_close

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_close.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.55 posix_trace_create

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_create.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.56 posix_trace_create_withlog

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_create_withlog.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.57 posix_trace_event

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_event.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.58 posix_trace_eventid_equal

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_eventid_equal.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.59 posix_trace_eventid_get_name

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_eventid_get_name.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.60 posix_trace_eventid_open

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_eventid_open.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.61 posix_trace_eventset_add

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_eventset_add.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.62 posix_trace_eventset_del

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_eventset_del.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.63 posix_trace_eventset_empty

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_eventset_empty.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.64 posix_trace_eventset_fill

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_eventset_fill.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.65 posix_trace_eventset_ismember

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_eventset_ismember.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.66 posix_trace_eventtypelist_getnext_id

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_eventtypelist_getnext_id.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.67 posix_trace_eventtypelist_rewind

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_eventtypelist_rewind.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.68 posix_trace_flush

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_flush.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.69 posix_trace_get_attr

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_get_attr.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.70 posix_trace_get_filter

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_get_filter.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.71 posix_trace_get_status

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_get_status.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.72 posix_trace_getnext_event

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_getnext_event.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.73 posix_trace_open

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_open.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.74 posix_trace_rewind

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_rewind.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.75 posix_trace_set_filter

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_set_filter.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.76 posix_trace_shutdown

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_shutdown.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.77 posix_trace_start

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_start.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.78 posix_trace_stop

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_stop.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.79 posix_trace_timedgetnext_event

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_timedgetnext_event.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.80 posix_trace_trid_eventid_open

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_trid_eventid_open.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.81 posix_trace_trygetnext_event

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/posix_trace_trygetnext_event.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.82 pthread_attr_getstackaddr

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/pthread_attr_getstackaddr.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11, Cygwin 1.7.9, mingw, MSVC 14, Android 9.0.
  • This function is not declared on some platforms: Android 13.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.83 pthread_attr_setstackaddr

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/pthread_attr_setstackaddr.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11, Cygwin 1.7.9, mingw, MSVC 14, Android 9.0.
  • This function is not declared on some platforms: Android 13.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.84 pthread_getconcurrency

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_getconcurrency.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 10.0, Minix 3.1.8, mingw, MSVC 14, Android 9.0.
  • This function is removed in POSIX.1-2024. You can remove calls to this function.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.85 pthread_setconcurrency

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_setconcurrency.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 10.0, Minix 3.1.8, mingw, MSVC 14, Android 9.0.
  • This function is removed in POSIX.1-2024. You can remove calls to this function.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.86 putmsg

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/putmsg.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.87 putpmsg

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/putpmsg.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.88 rindex

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/rindex.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 9.0.
  • This function is removed in POSIX.1-2008. Better use strrchr instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.89 scalb

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/scalb.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.90 setcontext

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/setcontext.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.
  • The effects of this call are system and compiler optimization dependent, since it restores the contents of register-allocated variables but not the contents of stack-allocated variables.

Note: A third-party implementation is available at https://github.com/kaniini/libucontext/.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.91 setitimer

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/setitimer.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.
  • This function is removed in POSIX.1-2024. Use the functions timer_create and timer_settime instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.92 setpgrp

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/setpgrp.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • This function is removed in POSIX.1-2024. Use the function setpgid or setsid instead, as appropriate.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.93 sighold

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/sighold.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14, Android 7.1.
  • This function is removed in POSIX.1-2024. Use the function sigprocmask instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.94 sigignore

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/sigignore.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 1.5.x, mingw, MSVC 14, Android 7.1.
  • This function is removed in POSIX.1-2024. Use the function sigaction instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.95 siginterrupt

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/siginterrupt.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.
  • This function is removed in POSIX.1-2024. Use the function sigaction instead.

Note: POSIX recommends using sigaction with SA_RESTART instead of siginterrupt (sig, 0).

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.96 sigpause

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/sigpause.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-sigpause-3.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 7.1.
  • This function is removed in POSIX.1-2024. Use the function sigsuspend instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.97 sigrelse

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/sigrelse.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14, Android 7.1.
  • This function is removed in POSIX.1-2024. Use the function sigprocmask instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.98 sigset

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/sigset.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 1.5.x, mingw, MSVC 14, Android 7.1.
  • This function is removed in POSIX.1-2024. Use the function sigaction instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.99 swapcontext

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/swapcontext.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.

Note: A third-party implementation is available at https://github.com/kaniini/libucontext/.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.100 tempnam

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/tempnam.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8.
  • This function is removed in POSIX.1-2024. Use the function mkstemp instead.
  • This function is not appropriate for creating temporary files. (It has security risks.) Better use mkstemp instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.101 toascii

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/toascii.html

Gnulib module: ctype

Portability problems fixed by Gnulib:

  • This function cannot be called from plain inline or extern inline functions on some platforms: macOS 10.8.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.102 ualarm

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/ualarm.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.103 ulimit

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/ulimit.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function is removed in POSIX.1-2024. Use the functions getrlimit and setrlimit instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.104 usleep

Removed in POSIX.1-2008. POSIX.1-2004 specification:
https://pubs.opengroup.org/onlinepubs/009695399/functions/usleep.html

Gnulib module: usleep

Portability problems fixed by Gnulib:

  • On some systems, usleep rejects attempts to sleep longer than 1 second, as allowed by POSIX: NetBSD 10.0, mingw.

Portability problems not fixed by Gnulib:

  • According to POSIX, the usleep function may interfere with the program’s use of the SIGALRM signal. On Linux, it doesn’t; on other platforms, it may.
  • On some systems, usleep may sleep for less than the indicated duration: Cygwin 3.5.3.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.105 utime

Removed in POSIX.1-2024. POSIX.1-2017 specification:
https://pubs.opengroup.org/onlinepubs/9699919799/functions/utime.html

Gnulib module: utime

Portability problems fixed by Gnulib:

  • The times that are set on the file are affected by the current time zone and by the DST flag of the current time zone on some platforms: mingw, MSVC 14 (when the environment variable TZ is set).
  • On some platforms, the prototype for utime omits const for the second argument: mingw, MSVC 14.
  • On some platforms, utime("link-to-file/",buf) succeeds instead of failing with ENOTDIR. macOS 14.

Portability problems not fixed by Gnulib:

  • On some platforms, this function mis-handles a trailing slash: Solaris 9.
  • This function cannot set full timestamp resolution. Use utimensat(AT_FDCWD,file,times,0), or the gnulib module utimens, instead.
  • This function sets a slightly different time stamp than the requested one: Haiku.
  • This function is removed in POSIX.1-2024. You can use Gnulib module utimens instead.

Next: , Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.106 vfork

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/vfork.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Previous: , Up: Past POSIX Function Substitutes   [Contents][Index]

12.107 wcswcs

Removed in POSIX.1-2008. POSIX.1-2004 specification: https://pubs.opengroup.org/onlinepubs/009695399/functions/wcswcs.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function is not declared on some platforms: Android 13.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.
  • This function is removed in POSIX.1-2008. Better use wcsstr instead.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

13 Glibc Header File Substitutes

This chapter describes which header files contained in GNU libc but not specified by ISO C or POSIX are substituted by Gnulib, which portability pitfalls are fixed by Gnulib, and which (known) portability problems are not worked around by Gnulib.

The notation “Gnulib module: —” means that Gnulib does not provide a module providing a substitute for the header file. When the list “Portability problems not fixed by Gnulib” is empty, such a module is not needed: No portability problems are known. Otherwise, it indicates that such a module would be useful but is not available: No one so far found this header file important enough to contribute a substitute for it. If you need this particular header file, you may write to <bug-gnulib at gnu dot org>.

Next: , Up: Glibc Header File Substitutes   [Contents][Index]

13.1 a.out.h

Describes the structure of executables (and object files?) in the old a.out format.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: macOS 14, Solaris 11.4, mingw, MSVC 14, Android 9.0.
  • This header file is useless because most executables and object files are in ELF format on some platforms: glibc 2.3.6, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.2 aliases.h

Defines the type struct aliasent and declares the functions setaliasent, endaliasent, getaliasent, getaliasent_r, getaliasbyname, getaliasbyname_r.

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.3 alloca.h

Declares the alloca function of function-like macro.

Documentation:

Gnulib module: alloca

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.4 ar.h

Describes the structure of files produced by the ‘ar’ program. Defines the type struct ar_hdr and the macros ARMAG, SARMAG, ARFMAG.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.5 argp.h

Documentation:

Gnulib module: argp

Portability problems fixed by Gnulib:

  • This header file is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.6 argz.h

Documentation:

Gnulib module: argz

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.
  • The argz functions do not work on some platforms: Cygwin.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.7 byteswap.h

Defines the functions or function-like macros bswap_16, bswap_32, bswap_64.

Gnulib module: byteswap

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: macOS 14, FreeBSD 13.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.8 crypt.h

Defines the type struct crypt_data and declares the functions crypt, crypt_r, setkey, setkey_r, encrypt, encrypt_r.

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14, Android 9.0.
  • The functions crypt, setkey, encrypt are missing on some platforms: HP-UX 11.
  • The type struct crypt_data and the functions crypt_r, setkey_r, encrypt_r are missing on some platforms: Solaris 11.4, Cygwin.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.9 envz.h

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.10 err.h

Declares the functions warn, vwarn, warnx, vwarnx, err, verr, errx, verrx.

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 10, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.11 error.h

Declares the functions error, error_at_line and the variables error_print_progname, error_message_count, error_one_per_line.

Documentation:

Gnulib module: error-h

Portability problems fixed by Gnulib:

  • This header file is missing on many platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.9, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.12 execinfo.h

Declares the functions backtrace, backtrace_symbols, backtrace_symbols_fd.

Documentation:

Gnulib module: execinfo

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: musl libc, FreeBSD 9.3, NetBSD 6.1, OpenBSD 6.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

  • On platforms where the header file is missing, the Gnulib substitute implementation is just a stub, and does nothing.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.13 fpu_control.h

Handling of the FPU control word. Defines the fpu_control_t type, declares the __fpu_control variable, and defines the _FPU_GETCW, _FPU_SETCW macros.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.14 fstab.h

Defines the type struct fstab, the macros FSTAB_*, _PATH_FSTAB, and declares the functions setfsent, endfsent, getfsent, getfsspec, getfsfile.

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: Minix 3.1.8, Solaris 11.4, Cygwin, mingw, MSVC 14, Android 9.0.
  • The macro _PATH_FSTAB is missing on some platforms: AIX 5.1, HP-UX 11.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.15 fts.h

Defines the types FTS, FTSENT and the macros FTS_*, and declares the functions fts_open, fts_read, fts_children, fts_set, fts_close.

Documentation:

Gnulib module: fts

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 11.3, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.16 getopt.h

Defines the type struct option and declares the variables optarg, optind, opterr, optopt and the functions getopt, getopt_long, getopt_long_only.

Documentation:

Gnulib module: getopt-gnu

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: AIX 7.2, HP-UX 11, MSVC 14.
  • The function getopt_long is missing on some platforms: Solaris 9.
  • The function getopt_long_only is missing on some platforms: FreeBSD 5.2.1, NetBSD 10.0, Solaris 9, mingw.
  • The method to reset options is incompatible on some platforms: FreeBSD 6.0, NetBSD 10.0(?), OpenBSD 7.9, Cygwin 1.5.x, mingw.
  • The function getopt does not handle a leading ‘+’ character in the options string on some platforms: Solaris 11 2010-11.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.17 gshadow.h

Defines the type struct sgrp and declares the functions setsgent, endsgent, getsgent, getsgnam, sgetsgent, fgetsgent, putsgent, getsgent_r, getsgnam_r, sgetsgent_r, fgetsgent_r.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.18 ieee754.h

Defines the types union ieee754_float, union ieee754_double, union ieee854_long_double.

Gnulib module: ieee754-h

Portability problems fixed by Gnulib:

  • This header file is missing on all non-glibc platforms: glibc/sparc64 in 32-bit mode, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

  • The substitute for this header file has not been tested for long double and does not work on some platforms.
  • The substitute for this header file returns nonsense on (now-quite-rare) platforms that do not use IEEE floating point, such as Linux/m68k.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.19 ifaddrs.h

Defines the type struct ifaddrs and declares the functions getifaddrs, freeifaddrs.

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.21 malloc.h

Declares the function memalign and functions for customizing the malloc behavior.

Documentation:

Gnulib module: malloc-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: macOS 14, OpenBSD 7.9.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.22 mcheck.h

Defines the type enum mcheck_status and declares the functions mcheck, mcheck_pedantic, mcheck_check_all, mprobe, mtrace, muntrace.

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.23 mntent.h

Defines the type struct mntent and the macros MNTTAB, MOUNTED, MNTTYPE_*, MNTOPT_*, and declares the functions setmntent, getmntent, getmntent_r, addmntent, endmntent, hasmntopt.

Documentation:

Gnulib module: mntent-h

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, mingw, MSVC 14.
  • The function getmntent_r is missing on all non-glibc platforms: AIX 5.1, HP-UX 11, Cygwin, Android 9.0.

Gnulib module mountlist provides a higher-level abstraction.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.24 obstack.h

Documentation:

Gnulib module: obstack

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.25 paths.h

Defines the macros _PATH_*.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: Minix 3.1.8, HP-UX 11, Solaris 11 2010-11, mingw, MSVC 14.
  • The set of _PATH_* macros is platform dependent.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.26 printf.h

Defines the type struct printf_info and the macros and enum values PA_*, and declares the functions printf_function, printf_arginfo_function, register_printf_function, parse_printf_format, printf_size, printf_size_info.

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.27 pty.h

Declares the functions openpty and forkpty.

Documentation:

Gnulib module: pty-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms that declare the forkpty and openpty functions in util.h or libutil.h instead: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9.
  • This header file is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4.

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.28 resolv.h

Defines the types res_sendhookact, res_send_qhook, res_send_rhook, res_state, struct res_sym and the macros _PATH_RESCONF, RES_*, and declares the functions res_close, res_init, res_mkquery, res_query, res_querydomain, res_search, res_send.

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: Cygwin 1.5.x, mingw, MSVC 14.
  • The functions are missing on some platforms: HP-UX 11.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.29 shadow.h

Defines the type struct spwd and declares the functions setspent, endspent, getspent, getspent_r, getspnam, getspnam_r, sgetspent, sgetspent_r, fgetspent, fgetspent_r, putspent, lckpwdf, ulckpwdf.

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Cygwin, mingw, MSVC 14, Android 9.0.
  • The functions getspent_r, getspnam_r, sgetspent_r, fgetspent, fgetspent_r, putspent are missing on some platforms: HP-UX 11.
  • The functions sgetspent, sgetspent_r are missing on some platforms: HP-UX 11, Solaris 11.4.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.30 sys/file.h

Declares the function flock.

Gnulib module: sys_file-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: MSVC 14.

Portability problems not fixed by Gnulib:

  • This header file does not declare the flock function on some platforms: AIX 7.1, HP-UX 11.23, Solaris 11.4.

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.31 sys/ioctl.h

Declares the function ioctl.

Documentation:

Gnulib module: sys_ioctl-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.
  • This header file does not declare the ioctl function on some platforms: AIX 5.1, Solaris 11.4, Haiku 2017.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.32 sys/random.h

Declares the function getrandom and the flags for it.

Documentation:

Gnulib module: sys_random-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: glibc 2.24, NetBSD 9.3, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.11, Cygwin 2.6.x, mingw, MSVC 14.
  • This header file is not self-contained on some platforms: uClibc, macOS 11.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.33 sysexits.h

Defines the EX_* macros, including EX_OK.

Gnulib module: sysexits-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: mingw, MSVC 14.
  • This header file defines no EX_* macros if _BSD_SOURCE is not defined on some platforms: Haiku.
  • The macro EX_CONFIG is missing on some platforms: HP-UX 11.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.34 ttyent.h

Defines the type struct ttyent and declares the functions setttyent, endttyent, getttyent, getttynam.

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This header file is missing on some platforms: HP-UX 11, Solaris 11.4, Cygwin, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc Header File Substitutes   [Contents][Index]

13.35 utmp.h

Defines functions for login and logout (to a tty session) and for examining the history of logins and logouts.

Documentation:

Gnulib module: utmp-h

Portability problems fixed by Gnulib:

  • This header file is missing on some platforms: FreeBSD 14.0, mingw, MSVC 14.
  • <sys/types.h> is a prerequisite of <utmp.h> on some platforms: FreeBSD 8.0, OpenBSD 7.2.

Portability problems not fixed by Gnulib:

  • While some platforms have the struct utmp field ut_user, older platforms have the field ut_name.
  • The struct utmp fields ut_id, ut_pid, ut_type do not exist on some platforms: macOS, old FreeBSD, NetBSD, OpenBSD, Minix.
  • The struct utmp field ut_host does not exist on some platforms: Solaris.
  • The struct utmp field ut_exit does not exist on some platforms: macOS, old FreeBSD, NetBSD, OpenBSD, Minix, Cygwin.
  • The struct utmp field ut_session does not exist on some platforms: macOS, old FreeBSD, NetBSD, OpenBSD, Minix, AIX, HP-UX, Solaris, Cygwin.
  • The struct utmp field ut_addr or ut_addr_v6 does not exist on some platforms: macOS, old FreeBSD, NetBSD, OpenBSD, Minix, AIX, Solaris.
  • On some platforms, this API does not support timestamps past the year 2038: glibc 2.38 on 32-bit platforms like x86 and ARM where time_t was historically 32 bits.
  • On some platforms, this header misbehaves if the year2038 or year2038-recommended modules are used and the program is configured without the --disable-year2038 option. The readutmp module works around this problem: glibc 2.38 on 32-bit platforms like x86 and ARM where time_t was historically 32 bits. See Avoiding the year 2038 problem.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

14 Glibc Function Substitutes

This chapter describes which functions and function-like macros provided as extensions by at least GNU libc are also supported by Gnulib, which portability pitfalls are fixed by Gnulib, and which (known) portability problems are not worked around by Gnulib.

The notation “Gnulib module: —” means that Gnulib does not provide a module providing a substitute for the function. When the list “Portability problems not fixed by Gnulib” is empty, such a module is not needed: No portability problems are known. Otherwise, it indicates that such a module would be useful but is not available: No one so far found this function important enough to contribute a substitute for it. If you need this particular function, you may write to <bug-gnulib at gnu dot org>.

This list of functions is sorted according to the header that declares them.

Next: , Up: Glibc Function Substitutes   [Contents][Index]

14.1 Glibc Extensions to <aio.h>

Up: Glibc Extensions to <aio.h>   [Contents][Index]

14.1.1 aio_init

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.2 Glibc <aliases.h>

Next: , Up: Glibc <aliases.h>   [Contents][Index]

14.2.1 endaliasent

Documentation:
man endaliasent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <aliases.h>   [Contents][Index]

14.2.2 getaliasbyname

Documentation:
man getaliasbyname

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <aliases.h>   [Contents][Index]

14.2.3 getaliasbyname_r

Documentation:
man getaliasbyname_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <aliases.h>   [Contents][Index]

14.2.4 getaliasent

Documentation:
man getaliasent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <aliases.h>   [Contents][Index]

14.2.5 getaliasent_r

Documentation:
man getaliasent_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <aliases.h>   [Contents][Index]

14.2.6 setaliasent

Documentation:
man setaliasent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.3 Glibc <argp.h>

Next: , Up: Glibc <argp.h>   [Contents][Index]

14.3.1 argp_err_exit_status

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Argp-Global-Variables.html.

Gnulib module: argp

Portability problems fixed by Gnulib:

  • This variable is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <argp.h>   [Contents][Index]

14.3.2 argp_error

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Argp-Helper-Functions.html.

Gnulib module: argp

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <argp.h>   [Contents][Index]

14.3.3 argp_failure

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Argp-Helper-Functions.html.

Gnulib module: argp

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <argp.h>   [Contents][Index]

14.3.4 argp_help

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Argp-Help.html.

Gnulib module: argp

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <argp.h>   [Contents][Index]

14.3.5 argp_parse

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Argp.html.

Gnulib module: argp

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <argp.h>   [Contents][Index]

14.3.6 argp_program_bug_address

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Argp-Global-Variables.html.

Gnulib module: argp

Portability problems fixed by Gnulib:

  • This variable is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <argp.h>   [Contents][Index]

14.3.7 argp_program_version

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Argp-Global-Variables.html.

Gnulib module: argp

Portability problems fixed by Gnulib:

  • This variable is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <argp.h>   [Contents][Index]

14.3.8 argp_program_version_hook

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Argp-Global-Variables.html.

Gnulib module: argp

Portability problems fixed by Gnulib:

  • This variable is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <argp.h>   [Contents][Index]

14.3.9 argp_state_help

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Argp-Helper-Functions.html.

Gnulib module: argp

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Previous: , Up: Glibc <argp.h>   [Contents][Index]

14.3.10 argp_usage

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Argp-Helper-Functions.html.

Gnulib module: argp

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.4 Glibc <argz.h>

Next: , Up: Glibc <argz.h>   [Contents][Index]

14.4.1 argz_add

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-argz-add.html

Documentation:

Gnulib module: argz

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.
  • This function is broken on some platforms: Cygwin 1.5.24.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <argz.h>   [Contents][Index]

14.4.2 argz_add_sep

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-argz-add.html

Documentation:

Gnulib module: argz

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.
  • This function is broken on some platforms: Cygwin 1.5.24.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <argz.h>   [Contents][Index]

14.4.3 argz_append

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-argz-add.html

Documentation:

Gnulib module: argz

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.
  • This function is broken on some platforms: Cygwin 1.5.24.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <argz.h>   [Contents][Index]

14.4.4 argz_count

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-argz-add.html

Documentation:

Gnulib module: argz

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.
  • This function is broken on some platforms: Cygwin 1.5.24.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <argz.h>   [Contents][Index]

14.4.5 argz_create

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-argz-add.html

Documentation:

Gnulib module: argz

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.
  • This function is broken on some platforms: Cygwin 1.5.24.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <argz.h>   [Contents][Index]

14.4.6 argz_create_sep

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-argz-add.html

Documentation:

Gnulib module: argz

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.
  • This function is broken on some platforms: Cygwin 1.5.24.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <argz.h>   [Contents][Index]

14.4.7 argz_delete

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-argz-add.html

Documentation:

Gnulib module: argz

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.
  • This function is broken on some platforms: Cygwin 1.5.24.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <argz.h>   [Contents][Index]

14.4.8 argz_extract

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-argz-add.html

Documentation:

Gnulib module: argz

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.
  • This function is broken on some platforms: Cygwin 1.5.24.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <argz.h>   [Contents][Index]

14.4.9 argz_insert

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-argz-add.html

Documentation:

Gnulib module: argz

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.
  • This function is broken on some platforms: Cygwin 1.5.24.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <argz.h>   [Contents][Index]

14.4.10 argz_next

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-argz-add.html

Documentation:

Gnulib module: argz

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.
  • This function is broken on some platforms: Cygwin 1.5.24.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <argz.h>   [Contents][Index]

14.4.11 argz_replace

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-argz-add.html

Documentation:

Gnulib module: argz

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.
  • This function is broken on some platforms: Cygwin 1.5.24.

Portability problems not fixed by Gnulib:

Previous: , Up: Glibc <argz.h>   [Contents][Index]

14.4.12 argz_stringify

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-argz-add.html

Documentation:

Gnulib module: argz

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.
  • This function is broken on some platforms: Cygwin 1.5.24.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.5 Glibc Extensions to <arpa/inet.h>

Next: , Up: Glibc Extensions to <arpa/inet.h>   [Contents][Index]

14.5.1 inet_aton

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-inet-aton-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <arpa/inet.h>   [Contents][Index]

14.5.2 inet_lnaof

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Glibc Extensions to <arpa/inet.h>   [Contents][Index]

14.5.3 inet_makeaddr

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Glibc Extensions to <arpa/inet.h>   [Contents][Index]

14.5.4 inet_net_ntop

Documentation:
man inet_net_ntop

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.00, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <arpa/inet.h>   [Contents][Index]

14.5.5 inet_net_pton

Documentation:
man inet_net_pton

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.00, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <arpa/inet.h>   [Contents][Index]

14.5.6 inet_netof

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Glibc Extensions to <arpa/inet.h>   [Contents][Index]

14.5.7 inet_network

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Glibc Extensions to <arpa/inet.h>   [Contents][Index]

14.5.8 inet_nsap_addr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, HP-UX 11.00, Cygwin 2.9, mingw, MSVC 14.

Previous: , Up: Glibc Extensions to <arpa/inet.h>   [Contents][Index]

14.5.9 inet_nsap_ntoa

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, HP-UX 11.00, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.6 Glibc Extensions to <arpa/nameser.h>

Next: , Up: Glibc Extensions to <arpa/nameser.h>   [Contents][Index]

14.6.1 ns_name_compress

Documentation:
https://web.deu.edu.tr/doc/oreily/networking/dnsbind/ch14_02.htm

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.33, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <arpa/nameser.h>   [Contents][Index]

14.6.2 ns_name_ntop

Documentation: —

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.33, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <arpa/nameser.h>   [Contents][Index]

14.6.3 ns_name_pack

Documentation: —

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.33, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <arpa/nameser.h>   [Contents][Index]

14.6.4 ns_name_pton

Documentation: —

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.33, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <arpa/nameser.h>   [Contents][Index]

14.6.5 ns_name_skip

Documentation:
https://web.deu.edu.tr/doc/oreily/networking/dnsbind/ch14_02.htm

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.33, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <arpa/nameser.h>   [Contents][Index]

14.6.6 ns_name_uncompress

Documentation:
https://web.deu.edu.tr/doc/oreily/networking/dnsbind/ch14_02.htm

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.33, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc Extensions to <arpa/nameser.h>   [Contents][Index]

14.6.7 ns_name_unpack

Documentation: —

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.33, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

https://man7.org/linux/man-pages/man3/libsres.3.html https://www.kernel.org/doc/man-pages/online/pages/man3/

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.7 Glibc <byteswap.h>

Next: , Up: Glibc <byteswap.h>   [Contents][Index]

14.7.1 bswap_16

Documentation:
man bswap_16

Gnulib module: byteswap

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <byteswap.h>   [Contents][Index]

14.7.2 bswap_32

Documentation:
man bswap_32

Gnulib module: byteswap

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <byteswap.h>   [Contents][Index]

14.7.3 bswap_64

Documentation:
man bswap_64

Gnulib module: byteswap

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.8 Glibc Extensions to <complex.h>

Next: , Up: Glibc Extensions to <complex.h>   [Contents][Index]

14.8.1 clog10

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib---clog10.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 9, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <complex.h>   [Contents][Index]

14.8.2 clog10f

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib---clog10f.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 9, Android 9.0.

Previous: , Up: Glibc Extensions to <complex.h>   [Contents][Index]

14.8.3 clog10l

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib---clog10l.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 9, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.9 Glibc Extensions to <ctype.h>

Up: Glibc Extensions to <ctype.h>   [Contents][Index]

14.9.1 isctype

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.10 Glibc Extensions to <dirent.h>

Next: , Up: Glibc Extensions to <dirent.h>   [Contents][Index]

14.10.1 getdirentries

Documentation:
man getdirentries

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • On platforms where off_t is a 32-bit type, this function may not work correctly on huge directories larger than 2 GB. The fix is to use the AC_SYS_LARGEFILE macro.

Next: , Previous: , Up: Glibc Extensions to <dirent.h>   [Contents][Index]

14.10.2 scandirat

Documentation:
man scandirat

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.14, macOS 14, FreeBSD 13.0, NetBSD 10.0, OpenBSD 7.5, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 1.7.10, mingw, MSVC 14, Android 6.0.

Previous: , Up: Glibc Extensions to <dirent.h>   [Contents][Index]

14.10.3 versionsort

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 13.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.11 Glibc Extensions to <dlfcn.h>

Next: , Up: Glibc Extensions to <dlfcn.h>   [Contents][Index]

14.11.1 dladdr1

Documentation:
man dladdr1

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <dlfcn.h>   [Contents][Index]

14.11.2 dlinfo

Documentation:
man dlinfo

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <dlfcn.h>   [Contents][Index]

14.11.3 dlmopen

Documentation:
man dlmopen

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <dlfcn.h>   [Contents][Index]

14.11.4 dlvsym

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-dlvsym-1.html

Documentation:
man dlvsym

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 6.0.

Previous: , Up: Glibc Extensions to <dlfcn.h>   [Contents][Index]

14.11.5 _dl_find_object

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Dynamic-Linker-Introspection.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.12 Glibc <envz.h>

Next: , Up: Glibc <envz.h>   [Contents][Index]

14.12.1 envz_add

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-envz-add.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <envz.h>   [Contents][Index]

14.12.2 envz_entry

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-envz-add.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <envz.h>   [Contents][Index]

14.12.3 envz_get

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-envz-add.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <envz.h>   [Contents][Index]

14.12.4 envz_merge

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-envz-add.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <envz.h>   [Contents][Index]

14.12.5 envz_remove

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-envz-add.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <envz.h>   [Contents][Index]

14.12.6 envz_strip

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-envz-add.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.13 Glibc <err.h>

Next: , Up: Glibc <err.h>   [Contents][Index]

14.13.1 err

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-err-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 10, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <err.h>   [Contents][Index]

14.13.2 errx

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-errx-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 10, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <err.h>   [Contents][Index]

14.13.3 verr

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 10, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <err.h>   [Contents][Index]

14.13.4 verrx

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-verrx-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 10, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <err.h>   [Contents][Index]

14.13.5 vwarn

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 10, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <err.h>   [Contents][Index]

14.13.6 vwarnx

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 10, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <err.h>   [Contents][Index]

14.13.7 warn

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-warn-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 10, mingw, MSVC 14.

Previous: , Up: Glibc <err.h>   [Contents][Index]

14.13.8 warnx

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-warnx-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 10, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.14 Glibc Extensions to <errno.h>

Next: , Up: Glibc Extensions to <errno.h>   [Contents][Index]

14.14.1 program_invocation_name

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.7, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc Extensions to <errno.h>   [Contents][Index]

14.14.2 program_invocation_short_name

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.7, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.15 Glibc <error.h>

Next: , Up: Glibc <error.h>   [Contents][Index]

14.15.1 error

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-error-n.html

Documentation:

Gnulib module: error

Portability problems fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.9, mingw, MSVC 14, Android 5.1.
  • This function outputs an extra space if error_print_progname is set, on some platforms: Android 11.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <error.h>   [Contents][Index]

14.15.2 error_at_line

Documentation:

Gnulib module: error

Portability problems fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.9, mingw, MSVC 14, Android 5.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <error.h>   [Contents][Index]

14.15.3 error_message_count

Documentation:

Gnulib module: error

Portability problems fixed by Gnulib:

  • This variable is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.9, mingw, MSVC 14, Android 5.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <error.h>   [Contents][Index]

14.15.4 error_one_per_line

Documentation:

Gnulib module: error

Portability problems fixed by Gnulib:

  • This variable is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.9, mingw, MSVC 14, Android 5.1.

Portability problems not fixed by Gnulib:

Previous: , Up: Glibc <error.h>   [Contents][Index]

14.15.5 error_print_progname

Documentation:
man error_print_progname

Gnulib module: error

Portability problems fixed by Gnulib:

  • This variable is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.9, mingw, MSVC 14, Android 5.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.16 Glibc <execinfo.h>

Next: , Up: Glibc <execinfo.h>   [Contents][Index]

14.16.1 backtrace

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-backtrace-1.html

Documentation:

Gnulib module: execinfo

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: musl libc, FreeBSD 9.3, NetBSD 6.1, OpenBSD 6.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 2.9, mingw, MSVC 14, Android API level 32.

Portability problems not fixed by Gnulib:

  • The second argument is of type size_t, not int, on some platforms: FreeBSD, NetBSD, OpenBSD.
  • The return value may be (size_t)(-1) instead of 0 on some platforms: FreeBSD 12.4/i386.
  • The returned stack trace is empty if it would not entirely fit into the provided buffer on some platforms: FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9.
  • The returned stack trace is always empty on some platforms: FreeBSD 11.0/i386, FreeBSD 12.2/sparc64.
  • On platforms where the function is missing, the Gnulib substitute implementation is just a stub, and does nothing.

Next: , Previous: , Up: Glibc <execinfo.h>   [Contents][Index]

14.16.2 backtrace_symbols

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-backtrace-1.html

Documentation:

Gnulib module: execinfo

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: musl libc, FreeBSD 9.3, NetBSD 6.1, OpenBSD 6.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 2.9, mingw, MSVC 14, Android API level 32.

Portability problems not fixed by Gnulib:

  • The second argument is of type size_t, not int, on some platforms: FreeBSD, NetBSD, OpenBSD.
  • On platforms where the function is missing, the Gnulib substitute implementation is just a stub, and does nothing.

Previous: , Up: Glibc <execinfo.h>   [Contents][Index]

14.16.3 backtrace_symbols_fd

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-backtrace-1.html

Documentation:

Gnulib module: execinfo

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: musl libc, FreeBSD 9.3, NetBSD 6.1, OpenBSD 6.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 2.9, mingw, MSVC 14, Android API level 32.

Portability problems not fixed by Gnulib:

  • The second argument is of type size_t, not int, on some platforms: FreeBSD, NetBSD, OpenBSD.
  • The strings printed by this function not the same as the strings returned by backtrace_symbols on some platforms: glibc 2.39.
  • On platforms where the function is missing, the Gnulib substitute implementation is just a stub, and does nothing.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.17 Glibc Extensions to <fcntl.h>

Next: , Up: Glibc Extensions to <fcntl.h>   [Contents][Index]

14.17.1 fallocate

Documentation:
man fallocate

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.9, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 3.4.x, mingw, MSVC 14, Android 4.4.
  • On platforms where off_t is a 32-bit type, this function may not work correctly across the entire data range of files larger than 2 GB. The fix is to use the AC_SYS_LARGEFILE macro.

Next: , Previous: , Up: Glibc Extensions to <fcntl.h>   [Contents][Index]

14.17.2 name_to_handle_at

Documentation:
man name_to_handle_at

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on all non-glibc platforms: glibc 2.13, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • When AT_EMPTY_PATH is used, this function does not allow the file name to be a null pointer: Linux kernel 6.10.

Next: , Previous: , Up: Glibc Extensions to <fcntl.h>   [Contents][Index]

14.17.3 readahead

Documentation:
man readahead

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 4.0.4.

Next: , Previous: , Up: Glibc Extensions to <fcntl.h>   [Contents][Index]

14.17.4 open_by_handle_at

Documentation:
man open_by_handle_at

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on all non-glibc platforms: glibc 2.13, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <fcntl.h>   [Contents][Index]

14.17.5 openat2

Documentation:
man openat2

Gnulib module: openat2

Portability problems fixed by Gnulib:

  • This function is missing on most platforms: glibc 2.42 on Linux, glibc on non-Linux, all non-glibc platforms.

Portability problems not fixed by Gnulib:

  • On platforms that do not natively support openat2 functionality, the Gnulib emulation might not act atomically.

Previous: , Up: Glibc Extensions to <fcntl.h>   [Contents][Index]

14.17.6 sync_file_range

Documentation:
man sync_file_range

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.5, GNU/Hurd, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 4.3.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.18 Glibc Extensions to <fenv.h>

Next: , Up: Glibc Extensions to <fenv.h>   [Contents][Index]

14.18.1 fedisableexcept

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fedisableexcept.html

Documentation:

Gnulib module: fenv-exceptions-trapping

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, musl libc, FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.7, mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <fenv.h>   [Contents][Index]

14.18.2 feenableexcept

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-feenableexcept.html

Documentation:

Gnulib module: fenv-exceptions-trapping

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, musl libc, FreeBSD 5.2.1, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.7, mingw, MSVC 14, Android 4.4.
  • This function does not detect failures on glibc 2.19/aarch64, FreeBSD 12.2/arm, FreeBSD 12.2/arm64, NetBSD 10.0/arm64.
  • This function is broken on mingw 14.0.0.

Portability problems not fixed by Gnulib:

  • The resulting signal is SIGILL instead of SIGFPE on some platforms: Linux/hppa, macOS 14/arm64.

Previous: , Up: Glibc Extensions to <fenv.h>   [Contents][Index]

14.18.3 fegetexcept

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fegetexcept.html

Documentation:

Gnulib module: fenv-exceptions-trapping

Portability problems fixed by Gnulib:

  • This function is missing on many non-glibc platforms: Mac OS X 10.4, musl libc, FreeBSD 14.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.7, mingw, MSVC 14, Android 4.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.19 Glibc Extensions to <fmtmsg.h>

Up: Glibc Extensions to <fmtmsg.h>   [Contents][Index]

14.19.1 addseverity

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.20 Glibc <fstab.h>

Next: , Up: Glibc <fstab.h>   [Contents][Index]

14.20.1 endfsent

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <fstab.h>   [Contents][Index]

14.20.2 getfsent

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <fstab.h>   [Contents][Index]

14.20.3 getfsfile

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <fstab.h>   [Contents][Index]

14.20.4 getfsspec

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <fstab.h>   [Contents][Index]

14.20.5 setfsent

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.21 Glibc <fts.h>

Next: , Up: Glibc <fts.h>   [Contents][Index]

14.21.1 fts_children

Documentation:
man fts_children

Gnulib module: fts

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 11.3, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, this function may not correctly report the size of files or block devices larger than 2 GB and may not work correctly on huge directories larger than 2 GB. Also, on platforms where ino_t is a 32-bit type, this function may report inode numbers incorrectly. The fix is to use the AC_SYS_LARGEFILE macro (only on Mac OS X systems).

Next: , Previous: , Up: Glibc <fts.h>   [Contents][Index]

14.21.2 fts_close

Documentation:
man fts_close

Gnulib module: fts

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 11.3, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <fts.h>   [Contents][Index]

14.21.3 fts_open

Documentation:
man fts_open

Gnulib module: fts

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 11.3, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc <fts.h>   [Contents][Index]

14.21.4 fts_read

Documentation:
man fts_read

Gnulib module: fts

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 11.3, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • On platforms where off_t is a 32-bit type, this function may not correctly report the size of files or block devices larger than 2 GB and may not work correctly on huge directories larger than 2 GB. Also, on platforms where ino_t is a 32-bit type, this function may report inode numbers incorrectly. The fix is to use the AC_SYS_LARGEFILE macro (only on Mac OS X systems).

Previous: , Up: Glibc <fts.h>   [Contents][Index]

14.21.5 fts_set

Documentation:
man fts_set

Gnulib module: fts

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 11.3, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.22 Glibc <getopt.h>

Next: , Up: Glibc <getopt.h>   [Contents][Index]

14.22.1 getopt_long

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getopt-long-3.html

Documentation:

Gnulib module: getopt-gnu

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, MSVC 14.
  • The function getopt_long does not obey the combination of ‘+’ and ‘:’ flags in the options string on some platforms: glibc 2.11.
  • The use of ‘W;’ in the optstring argument to does not always allow -W foo to behave synonymously with --foo: glibc 2.11.
  • The function getopt_long does not support the ‘+’ flag in the options string on some platforms: macOS 14, AIX 5.2, Solaris 10.
  • The value of optind after a missing required argument is wrong on some platforms: macOS 14.
  • The function getopt_long does not obey the ‘-’ flag in the options string when POSIXLY_CORRECT is set on some platforms: Cygwin 1.7.0.
  • Some implementations fail to reset state, including re-checking POSIXLY_CORRECT, when optind is set to ‘0’: NetBSD, Cygwin 1.7.0.
  • The function getopt_long does not support options with optional arguments on some platforms: macOS 14, OpenBSD 4.0, AIX 5.2, Solaris 11 2010-11, Cygwin 1.5.x.
  • This function crashes if the option string includes W; but there are no long options, on some platforms: glibc 2.14.

Portability problems not fixed by Gnulib:

Gnulib provides also a module options, that fixes the following shortcomings of the getopt_long API.

These shortcomings are best illustrated with an example: 

static struct option const long_options[] =
{
  { "width", required_argument, NULL, 'w' },
  { "help", no_argument, &show_help, 1 },
  { "version", no_argument, &show_version, 1 },
  { NULL, 0, NULL, 0 }
};

while ((optchar = getopt_long (argc, argv, "w:xhV", long_options, NULL))
       != -1)
  switch (optchar)
    {
    case '\0':           /* Long option with flag != NULL.  */
      break;
    case 'w':
      set_width (optarg);
      break;
    case 'x':
      do_x = true;
      break;
    case 'h':
      show_help = 1;     /* Action code duplication!  */
      break;
    case 'V':
      show_version = 1;  /* Action code duplication!  */
      break;
    default:
      usage (EXIT_FAILURE);
    }
  • The information whether an option takes a required vs. optional argument needs to be specified twice: in the option[] array for the long option and in the string argument for the short option. It is too easy to forget to add the ":" or "::" part in the string argument and thus get inconsistent behaviour between the long option and the short option.
  • This information needs to be specified twice, but in different ways:
    In the arrayIn the string
    no_argument""
    required_argument":"
    optional_argument"::"
  • For an action that merely sets an int-typed variable to a value, you can specify this action in the options[] array, and thus omit the handling in the switch statement. But this works only for options that are long options without a corresponding short option. As soon as the option has a corresponding short option, you do need to handle it in the switch statement. Here again, there is the opportunity for inconsistent behaviour between the long option and the short option.
  • The val field in a struct option has different meanings, depending on another field: If the flag field is non-NULL, val is a value to be stored in a variable. If the flag field is NULL, val is a key to be returned from getopt_long and subject to the switch statement.
  • The handling of non-option arguments is specified by prepending a certain character (‘+’ or ‘-’) to the string argument. This is not one of the usual ways to specify things in an API. The conventional way in an API is an argument of enum type, or a flags word.
  • The handling of errors consists of two independent flags, and each of the flags has to be specified in a different way: one flag is specified by prepending a certain character (‘:’) to the string argument; the other flag is specified through the global variable opterr.
  • The struct option is a misnomer: It cannot encode short options. Therefore, it would have better been called struct long_option.
  • The getopt_long function is expected to receive the same arguments in each call, in the while loop. The effects are undefined if you don’t follow this (unwritten!) constraint.
  • The fifth argument to getopt_long, indexptr, is redundant, because when the flag is non-NULL, the switch statement does not need to handle the option, and when the flag is NULL, getopt_long returns the value of val, as a way to identify which option was seen.

Previous: , Up: Glibc <getopt.h>   [Contents][Index]

14.22.2 getopt_long_only

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getopt-long-only-3.html

Documentation:

Gnulib module: getopt-gnu

Portability problems fixed by Gnulib:

  • The function getopt_long_only does not obey the combination of ‘+’ and ‘:’ flags in the options string on some platforms: glibc 2.11.
  • The use of ‘W;’ in the optstring argument to does not always allow -W foo to behave synonymously with --foo: glibc 2.11.
  • The function getopt_long_only does not support the ‘+’ flag in the options string on some platforms: macOS 14, AIX 5.2, Solaris 10.
  • The value of optind after a missing required argument is wrong on some platforms: macOS 14.
  • The function getopt_long_only does not obey the ‘-’ flag in the options string when POSIXLY_CORRECT is set on some platforms: Cygwin 1.7.0.
  • Some implementations fail to reset state, including re-checking POSIXLY_CORRECT, when optind is set to ‘0’: NetBSD, Cygwin 1.7.0.
  • The function getopt_long_only does not support options with optional arguments on some platforms: macOS 14, OpenBSD 4.0, AIX 5.2, Solaris 11 2010-11, Cygwin 1.5.x.
  • This function is missing on some platforms: FreeBSD 5.2.1, NetBSD 10.0, Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14.
  • This function crashes if the option string includes W; but there are no long options, on some platforms: glibc 2.14.

Portability problems not fixed by Gnulib:

  • Some implementations return success instead of reporting an ambiguity if user’s option is a prefix of two long options with the same outcome: FreeBSD.
  • The GNU Coding Standards discourage the use of getopt_long_only in new programs.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.23 Glibc Extensions to <glob.h>

Up: Glibc Extensions to <glob.h>   [Contents][Index]

14.23.1 glob_pattern_p

Gnulib module: glob

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on most non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.24 Glibc Extensions to <gnu/libc-version.h>

Next: , Up: Glibc Extensions to <gnu/libc-version.h>   [Contents][Index]

14.24.1 gnu_get_libc_release

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-gnu-get-libc-version-1.html

Documentation:
man gnu_get_libc_release

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc Extensions to <gnu/libc-version.h>   [Contents][Index]

14.24.2 gnu_get_libc_version

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-gnu-get-libc-version-1.html

Documentation:
man gnu_get_libc_version

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.25 Glibc Extensions to <grp.h>

Next: , Up: Glibc Extensions to <grp.h>   [Contents][Index]

14.25.1 fgetgrent

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <grp.h>   [Contents][Index]

14.25.2 fgetgrent_r

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <grp.h>   [Contents][Index]

14.25.3 getgrent_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getgrent-r-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <grp.h>   [Contents][Index]

14.25.4 getgrouplist

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getgrouplist-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function takes int instead of gid_t parameters on some platforms: OS X 10.11.
  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.0, Cygwin 1.7.9, mingw, MSVC 14.

The Gnulib module getugroups provides a similar API.

Next: , Previous: , Up: Glibc Extensions to <grp.h>   [Contents][Index]

14.25.5 initgroups

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-initgroups-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is unsafe to call between fork and exec if the parent process is multi-threaded. Instead, use getgroups or getgrouplist (or use the gnulib module mgetgroups) before forking, and setgroups in the child.
  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <grp.h>   [Contents][Index]

14.25.6 putgrent

Documentation:
man putgrent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc Extensions to <grp.h>   [Contents][Index]

14.25.7 setgroups

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-setgroups-2.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, mingw, MSVC 14.
  • On very old systems, this function operated on an array of ‘int’, even though that was a different size than an array of ‘gid_t’; you can use autoconf’s AC_TYPE_GETGROUPS to set GETGROUPS_T to the appropriate size (since getgroups and setgroups share the same bug).

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.26 Glibc <gshadow.h>

Next: , Up: Glibc <gshadow.h>   [Contents][Index]

14.26.1 endsgent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.9, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <gshadow.h>   [Contents][Index]

14.26.2 fgetsgent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.9, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <gshadow.h>   [Contents][Index]

14.26.3 fgetsgent_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.9, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <gshadow.h>   [Contents][Index]

14.26.4 getsgent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.9, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <gshadow.h>   [Contents][Index]

14.26.5 getsgent_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.9, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <gshadow.h>   [Contents][Index]

14.26.6 getsgnam

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.9, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <gshadow.h>   [Contents][Index]

14.26.7 getsgnam_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.9, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <gshadow.h>   [Contents][Index]

14.26.8 putsgent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.9, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <gshadow.h>   [Contents][Index]

14.26.9 setsgent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.9, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <gshadow.h>   [Contents][Index]

14.26.10 sgetsgent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.9, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <gshadow.h>   [Contents][Index]

14.26.11 sgetsgent_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.9, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.27 Glibc <ifaddrs.h>

Next: , Up: Glibc <ifaddrs.h>   [Contents][Index]

14.27.1 getifaddrs

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getifaddrs.html

Documentation:
man getifaddrs

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 6.0.

Previous: , Up: Glibc <ifaddrs.h>   [Contents][Index]

14.27.2 freeifaddrs

Documentation:
man freeifaddrs

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 6.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.29 Glibc <malloc.h>

Next: , Up: Glibc <malloc.h>   [Contents][Index]

14.29.1 mallinfo

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11 2010-11, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <malloc.h>   [Contents][Index]

14.29.2 mallinfo2

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.32, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <malloc.h>   [Contents][Index]

14.29.3 malloc_info

Documentation:
man malloc_info

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.9, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 5.1.

Next: , Previous: , Up: Glibc <malloc.h>   [Contents][Index]

14.29.4 malloc_stats

Documentation:
man malloc_stats

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <malloc.h>   [Contents][Index]

14.29.5 malloc_trim

Documentation:
man malloc_trim

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <malloc.h>   [Contents][Index]

14.29.6 malloc_usable_size

Documentation:
man malloc_usable_size

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11.00, Solaris 11.4, mingw, MSVC 14, Android 4.1.

Next: , Previous: , Up: Glibc <malloc.h>   [Contents][Index]

14.29.7 mallopt

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11 2010-11, mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: Glibc <malloc.h>   [Contents][Index]

14.29.8 memalign

Documentation:

Gnulib module: memalign

Portability problems fixed by Gnulib:

  • This function is declared in <stdlib.h> instead of <malloc.h> on some platforms: Solaris 11.
  • This function doesn’t accept an alignment of 1 or 2 on some platforms: Solaris 11.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 12.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11.00, mingw, MSVC 14.

The Gnulib module aligned-malloc provides functions for allocating and freeing blocks of suitably aligned memory.

Previous: , Up: Glibc <malloc.h>   [Contents][Index]

14.29.9 pvalloc

Documentation:
man pvalloc

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.30 Glibc Extensions to <math.h>

Next: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.1 drem

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-drem.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11, Solaris 11.4, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.2 dremf

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-dremf.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.3 dreml

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-dreml.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.4 finite

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-finite.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.5 finitef

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-finitef.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.6 finitel

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-finitel.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.7 gamma

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-gamma.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.8 gammaf

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-gammaf.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.9 gammal

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-gammal.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.10 isinff

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 4.4.
  • This function is not declared on some platforms: Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.11 isinfl

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • This function is not declared on some platforms: Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.12 isnanf

Documentation:

Gnulib module: isnanf

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, Minix 3.1.8, AIX 5.1, HP-UX 11, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.13 isnanl

Documentation:

Gnulib module: isnanl

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.7.x, MSVC 14, Android 4.4.
  • This function is not declared on some platforms: Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.14 j0f

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-j0f.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.15 j0l

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-j0l.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.16 j1f

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-j1f.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.17 j1l

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-j1l.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.18 jnf

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-jnf.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.19 jnl

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-jnl.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.20 lgamma_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-lgamma-r.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.5 x86, Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.21 lgammaf_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-lgammaf-r.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.5, Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.22 lgammal_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-lgammal-r.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 1.7.x, mingw, MSVC 14, Android 5.1.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.23 matherr

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-matherr-1.html

Documentation:
man matherr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.24 pow10

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-pow10.html

Documentation:
man pow10

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.25 pow10f

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-pow10f.html

Documentation:
man pow10f

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.26 pow10l

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-pow10l.html

Documentation:
man pow10l

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.27 scalbf

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-scalbf.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.28 scalbl

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-scalbl.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.29 significand

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-significand.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.30 significandf

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-significandf.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.31 significandl

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-significandl.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.32 sincos

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-sincos.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 11.0, NetBSD 9.3, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.33 sincosf

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-sincosf.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 11.0, NetBSD 9.3, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.34 sincosl

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-sincosl.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 11.0, NetBSD 9.3, OpenBSD 6.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.7.x, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.35 y0f

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-y0f.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.36 y0l

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-y0l.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.37 y1f

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-y1f.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.38 y1l

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-y1l.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.39 ynf

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-ynf.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14.

Previous: , Up: Glibc Extensions to <math.h>   [Contents][Index]

14.30.40 ynl

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-ynl.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.31 Glibc <mcheck.h>

Next: , Up: Glibc <mcheck.h>   [Contents][Index]

14.31.1 mcheck

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <mcheck.h>   [Contents][Index]

14.31.2 mcheck_check_all

Documentation:
man mcheck_check_all

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <mcheck.h>   [Contents][Index]

14.31.3 mcheck_pedantic

Documentation:
man mcheck_pedantic

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <mcheck.h>   [Contents][Index]

14.31.4 mprobe

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <mcheck.h>   [Contents][Index]

14.31.5 mtrace

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <mcheck.h>   [Contents][Index]

14.31.6 muntrace

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.32 Glibc <mntent.h>

Next: , Up: Glibc <mntent.h>   [Contents][Index]

14.32.1 addmntent

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <mntent.h>   [Contents][Index]

14.32.2 endmntent

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, mingw, MSVC 14, Android API level 20.

Next: , Previous: , Up: Glibc <mntent.h>   [Contents][Index]

14.32.3 getmntent

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <mntent.h>   [Contents][Index]

14.32.4 getmntent_r

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android API level 20.

Next: , Previous: , Up: Glibc <mntent.h>   [Contents][Index]

14.32.5 hasmntopt

Documentation:

Gnulib module: hasmntopt

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Cygwin 3.5.3, Android API level 25.
  • This function returns wrong results on some platforms: musl libc 1.2.5.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14.

Previous: , Up: Glibc <mntent.h>   [Contents][Index]

14.32.6 setmntent

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, mingw, MSVC 14, Android API level 20.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.33 Glibc Extensions to <netdb.h>

Next: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.1 endnetgrent

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.2 gethostbyaddr_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-gethostbyaddr-r-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 5.1.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.3 gethostbyname2

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-gethostbyname2-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.4 gethostbyname2_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-gethostbyname2-r-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 5.1.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.5 gethostbyname_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-gethostbyname-r-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.6 gethostent_r

Documentation:
man gethostent_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.7 getnetbyaddr_r

Documentation:
man getnetbyaddr_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.8 getnetbyname_r

Documentation:
man getnetbyname_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.9 getnetent_r

Documentation:
man getnetent_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.10 getnetgrent

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.11 getnetgrent_r

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.12 getprotobyname_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getprotobyname-r.html

Documentation:
man getprotobyname_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.13 getprotobynumber_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getprotobynumber-r.html

Documentation:
man getprotobynumber_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.14 getprotoent_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getprotoent-r.html

Documentation:
man getprotoent_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.15 getservbyname_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getservbyname-r.html

Documentation:
man getservbyname_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.16 getservbyport_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getservbyport-r.html

Documentation:
man getservbyport_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.17 getservent_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getservent-r.html

Documentation:
man getservent_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.18 herror

Documentation:
man herror

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.19 hstrerror

Documentation:
man hstrerror

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.20 innetgr

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.21 rcmd

Documentation:
man rcmd

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.22 rcmd_af

Documentation:
man rcmd_af

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11.11, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.23 rexec

Documentation:
man rexec

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.24 rexec_af

Documentation:
man rexec_af

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11.11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.25 rresvport

Documentation:
man rresvport

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.26 rresvport_af

Documentation:
man rresvport_af

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11.11, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.27 ruserok

Documentation:
man ruserok

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.28 ruserok_af

Documentation:
man ruserok_af

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc Extensions to <netdb.h>   [Contents][Index]

14.33.29 setnetgrent

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.34 Glibc <netinet/ether.h>

Next: , Up: Glibc <netinet/ether.h>   [Contents][Index]

14.34.1 ether_aton

Documentation:
man ether_aton

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 2.3.

Next: , Previous: , Up: Glibc <netinet/ether.h>   [Contents][Index]

14.34.2 ether_aton_r

Documentation:
man ether_aton_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 2.3.

Next: , Previous: , Up: Glibc <netinet/ether.h>   [Contents][Index]

14.34.3 ether_hostton

Documentation:
man ether_hostton

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <netinet/ether.h>   [Contents][Index]

14.34.4 ether_line

Documentation:
man ether_line

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <netinet/ether.h>   [Contents][Index]

14.34.5 ether_ntoa

Documentation:
man ether_ntoa

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 2.3.

Next: , Previous: , Up: Glibc <netinet/ether.h>   [Contents][Index]

14.34.6 ether_ntoa_r

Documentation:
man ether_ntoa_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 2.3.

Previous: , Up: Glibc <netinet/ether.h>   [Contents][Index]

14.34.7 ether_ntohost

Documentation:
man ether_ntohost

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.35 Glibc Extensions to <netinet/in.h>

Next: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.1 bindresvport

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-bindresvport-3.html

Documentation:
man bindresvport

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11, Cygwin 1.5.x, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.2 getipv4sourcefilter

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11.23, Solaris 10, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.3 getsourcefilter

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11.23, Solaris 10, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.4 inet6_option_alloc

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.5 inet6_option_append

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.6 inet6_option_find

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.7 inet6_option_init

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.8 inet6_option_next

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.9 inet6_option_space

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.10 inet6_opt_append

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.4, Mac OS X 10.5, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.2, HP-UX 11.31, Solaris 9, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.11 inet6_opt_find

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.4, Mac OS X 10.5, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.2, HP-UX 11.31, Solaris 9, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.12 inet6_opt_finish

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.4, Mac OS X 10.5, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.2, HP-UX 11.31, Solaris 9, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.13 inet6_opt_get_val

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.4, Mac OS X 10.5, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.2, HP-UX 11.31, Solaris 9, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.14 inet6_opt_init

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.4, Mac OS X 10.5, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.2, HP-UX 11.31, Solaris 9, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.15 inet6_opt_next

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.4, Mac OS X 10.5, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.2, HP-UX 11.31, Solaris 9, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.16 inet6_opt_set_val

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.4, Mac OS X 10.5, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.2, HP-UX 11.31, Solaris 9, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.17 inet6_rth_add

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.4, Mac OS X 10.5, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.2, HP-UX 11.31, Solaris 9, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.18 inet6_rth_getaddr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.4, Mac OS X 10.5, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.2, HP-UX 11.31, Solaris 9, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.19 inet6_rth_init

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.4, Mac OS X 10.5, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.2, HP-UX 11.31, Solaris 9, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.20 inet6_rth_reverse

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.4, Mac OS X 10.5, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.2, HP-UX 11.31, Solaris 9, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.21 inet6_rth_segments

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.4, Mac OS X 10.5, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.2, HP-UX 11.31, Solaris 9, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.22 inet6_rth_space

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.4, Mac OS X 10.5, NetBSD 3.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.2, HP-UX 11.31, Solaris 9, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.23 setipv4sourcefilter

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11.23, Solaris 10, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc Extensions to <netinet/in.h>   [Contents][Index]

14.35.24 setsourcefilter

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11.23, Solaris 10, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.36 Glibc <obstack.h>

Next: , Up: Glibc <obstack.h>   [Contents][Index]

14.36.1 obstack_alloc_failed_handler

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Preparing-for-Obstacks.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <obstack.h>   [Contents][Index]

14.36.2 obstack_exit_failure

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <obstack.h>   [Contents][Index]

14.36.3 obstack_free

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Freeing-Obstack-Objects.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <obstack.h>   [Contents][Index]

14.36.4 obstack_printf

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Dynamic-Output.html.

Gnulib module: obstack-printf or obstack-printf-posix or obstack-printf-gnu

Portability problems fixed by either Gnulib module obstack-printf or obstack-printf-posix or obstack-printf-gnu:

  • This function is missing on all non-glibc platforms: musl libc, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.

Portability problems fixed by either Gnulib module obstack-printf-posix or obstack-printf-gnu:

  • This function does not support size specifiers as in C99 (hh, ll, j, t, z) on some platforms: AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.24, old mingw, MSVC 9.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37.
  • printf of ‘long double’ numbers is unsupported on some platforms: mingw, MSVC 14.
  • printf "%f", "%e", "%g" of Infinity and NaN yields an incorrect result on some platforms: AIX 7.3, Solaris 11.4, mingw, MSVC 14.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not support the ‘a’ and ‘A’ directives on some platforms: FreeBSD 5.2.1, OpenBSD 4.0, AIX 5.2, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support the ‘F’ directive on some platforms: NetBSD 3.0, AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘ls’ directive on some platforms: OpenBSD 4.0, Cygwin 1.5.x, Haiku.
  • This function does not support precisions in the ‘ls’ directive correctly on some platforms: Solaris 11.4.
  • This function does not support format directives that access arguments in an arbitrary order, such as "%2$s", on some platforms: NetBSD 3.0, mingw, MSVC 14.
  • This function doesn’t support the ' flag on some platforms: NetBSD 3.0, Cygwin 1.5.24, mingw, MSVC 14.
  • This function does not round the argument of the ‘a’ directive correctly on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4.
  • printf "%010f" of NaN and Infinity yields an incorrect result (padded with zeroes) on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, AIX 7.3, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC/clang.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • This function does not support precisions larger than 512 or 1024 in integer, floating-point and pointer output on some platforms: Solaris 10/x86, mingw, MSVC/clang.
  • This function produces wrong output for the ‘lc’ directive with a NUL wide character argument on some platforms: musl libc 1.2.4.
  • This function can crash in out-of-memory conditions on some platforms: FreeBSD 14.0, NetBSD 5.0.

Portability problems fixed by Gnulib module obstack-printf-gnu:

  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.

Portability problems fixed by either Gnulib module obstack-printf-posix or obstack-printf-gnu and additionally the Gnulib module printf-with-n-directive:

  • This function does not support the ‘n’ directive on some platforms: MSVC 14.
  • This function does not fully support the ‘n’ directive on some platforms: HP-UX 11, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.

Previous: , Up: Glibc <obstack.h>   [Contents][Index]

14.36.5 obstack_vprintf

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Variable-Arguments-Output.html.

Gnulib module: obstack-printf or obstack-printf-posix or obstack-printf-gnu

Portability problems fixed by either Gnulib module obstack-printf or obstack-printf-posix or obstack-printf-gnu:

  • This function is missing on all non-glibc platforms: musl libc, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.

Portability problems fixed by either Gnulib module obstack-printf-posix or obstack-printf-gnu:

  • This function does not support size specifiers as in C99 (hh, ll, j, t, z) on some platforms: AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.24, old mingw, MSVC 9.
  • This function does not support size specifiers as in C23 (w8, w16, w32, w64, wf8, wf16, wf32, wf64) on some platforms: glibc 2.37.
  • printf of ‘long double’ numbers is unsupported on some platforms: mingw, MSVC 14.
  • printf "%f", "%e", "%g" of Infinity and NaN yields an incorrect result on some platforms: AIX 7.3, Solaris 11.4, mingw, MSVC 14.
  • This function doesn’t support the ' flag at all on some platforms: mingw without __USE_MINGW_ANSI_STDIO, MSVC 14.
  • This function doesn’t support the ' flag correctly for integers (it uses the decimal point instead of the thousands separator!) on some platforms: mingw with __USE_MINGW_ANSI_STDIO.
  • This function doesn’t support the ' flag together with a precision on an integer argument correctly on some platforms: glibc 2.36, FreeBSD 14.0, NetBSD 10.0, Solaris 11, Cygwin 3.6.0, Haiku.
  • This function doesn’t support the ' flag correctly in locales where the thousands separator is a multibyte character on some platforms: NetBSD 10.0, Solaris 11 OpenIndiana.
  • This function does not support the ‘a’ and ‘A’ directives on some platforms: FreeBSD 5.2.1, OpenBSD 4.0, AIX 5.2, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘b’ directive, required by ISO C23, on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android 9.0.
  • This function does not support the ‘F’ directive on some platforms: NetBSD 3.0, AIX 5.1, HP-UX 11.23, Solaris 9, Cygwin 1.5.x, mingw, MSVC 14.
  • This function does not support the ‘ls’ directive on some platforms: OpenBSD 4.0, Cygwin 1.5.x, Haiku.
  • This function does not support precisions in the ‘ls’ directive correctly on some platforms: Solaris 11.4.
  • This function does not support format directives that access arguments in an arbitrary order, such as "%2$s", on some platforms: NetBSD 3.0, mingw, MSVC 14.
  • This function doesn’t support the ' flag on some platforms: NetBSD 3.0, Cygwin 1.5.24, mingw, MSVC 14.
  • This function does not round the argument of the ‘a’ directive correctly on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4.
  • printf "%010f" of NaN and Infinity yields an incorrect result (padded with zeroes) on some platforms: Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, AIX 7.3, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC/clang.
  • printf "%#.0x" or "%#.0X" with a zero argument yields an incorrect result (non-empty) on some platforms: Mac OS X 10.6.
  • This function does not support precisions larger than 512 or 1024 in integer, floating-point and pointer output on some platforms: Solaris 10/x86, mingw, MSVC/clang.
  • This function produces wrong output for the ‘lc’ directive with a NUL wide character argument on some platforms: musl libc 1.2.4.
  • This function can crash in out-of-memory conditions on some platforms: FreeBSD 14.0, NetBSD 5.0.

Portability problems fixed by Gnulib module obstack-printf-gnu:

  • This function does not support the ‘B’ directive on some platforms: glibc 2.34, musl libc, macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, AIX 7.3, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC, Android 9.0.

Portability problems fixed by either Gnulib module obstack-printf-posix or obstack-printf-gnu and additionally the Gnulib module printf-with-n-directive:

  • This function does not support the ‘n’ directive on some platforms: MSVC 14.
  • This function does not fully support the ‘n’ directive on some platforms: HP-UX 11, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

  • The %m directive is not portable, use %s mapped to an argument of strerror(errno) (or a version of strerror_r) instead.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.37 Glibc <printf.h>

Next: , Up: Glibc <printf.h>   [Contents][Index]

14.37.1 parse_printf_format

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Parsing-a-Template-String.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <printf.h>   [Contents][Index]

14.37.2 printf_size

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Predefined-Printf-Handlers.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <printf.h>   [Contents][Index]

14.37.3 printf_size_info

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Predefined-Printf-Handlers.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <printf.h>   [Contents][Index]

14.37.4 register_printf_function

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Registering-New-Conversions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <printf.h>   [Contents][Index]

14.37.5 register_printf_modifier

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.9, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <printf.h>   [Contents][Index]

14.37.6 register_printf_specifier

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.9, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <printf.h>   [Contents][Index]

14.37.7 register_printf_type

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.9, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.38 Glibc Extensions to <pthread.h>

Next: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.1 pthread_attr_getaffinity_np

Documentation:
man pthread_attr_getaffinity_np

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.3.2, macOS 14, FreeBSD 6.4, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function has a different signature on some platforms: glibc 2.3.3.

Next: , Previous: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.2 pthread_attr_setaffinity_np

Documentation:
man pthread_attr_setaffinity_np

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.3.2, macOS 14, FreeBSD 6.4, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function has a different signature on some platforms: glibc 2.3.3.

Next: , Previous: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.3 pthread_attr_getsigmask_np

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Initial-Thread-Signal-Mask.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.31, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.4 pthread_attr_setsigmask_np

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Initial-Thread-Signal-Mask.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.31, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.5 pthread_clockjoin_np

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.6 pthread_getaffinity_np

Documentation:
man pthread_getaffinity_np

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.3.2, macOS 14, FreeBSD 6.4, NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.0.x, mingw, MSVC 14, Android API level 35.
  • This function has a different signature on some platforms: glibc 2.3.3.
  • The third parameter has a different type on some platforms: FreeBSD 14.0, NetBSD 10.0.

Next: , Previous: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.7 pthread_getattr_default_np

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.17, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.8 pthread_getattr_np

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-pthread-getattr-np-1.html

Documentation:
man pthread_getattr_np

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.7.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.9 pthread_getname_np

Documentation:
man pthread_getname_np

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.10 pthread_gettid_np

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on most non-glibc platforms: glibc 2.41, macOS 15, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.7, Minix, AIX 7.3, HP-UX 11.31, Solaris 11.4, Cygwin, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.11 pthread_kill_other_threads_np

Documentation:
man pthread_kill_other_threads_np

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.12 pthread_rwlockattr_getkind_np

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-pthread-rwlockattr-getkind-np-1.html

Documentation:
man pthread_rwlockattr_getkind_np

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 5.1.

Next: , Previous: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.13 pthread_rwlockattr_setkind_np

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-pthread-rwlockattr-getkind-np-1.html

Documentation:
man pthread_rwlockattr_setkind_np

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 5.1.

Next: , Previous: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.14 pthread_setaffinity_np

Documentation:
man pthread_setaffinity_np

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.3.2, macOS 14, FreeBSD 6.4, NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.0.x, mingw, MSVC 14, Android API level 35.
  • This function has a different signature on some platforms: glibc 2.3.3.
  • The third parameter has a different type on some platforms: FreeBSD 14.0, NetBSD 10.0.

Next: , Previous: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.15 pthread_setattr_default_np

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.17, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.16 pthread_setname_np

Documentation:
man pthread_setname_np

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.11, Mac OS X 10.5, FreeBSD 12.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.0, Cygwin 1.7.x, mingw, MSVC 14. See also https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3554.htm.
  • This function has a different signature on some platforms: macOS 14, NetBSD 10.0. On macOS the function takes only one argument, the name. On NetBSD the second argument is interpreted as a printf format string, with the third argument as parameter.

Next: , Previous: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.17 pthread_sigqueue

Documentation:
man pthread_sigqueue

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.10, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.0, Cygwin 1.7.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.18 pthread_timedjoin_np

Documentation:
man pthread_timedjoin_np

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.3.2, macOS 14, FreeBSD 6.4, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.10.x, mingw, MSVC 14, Android 9.0.
  • FreeBSD 6.4 has a function of this name in libthr but not in libpthread, and it also is missing a declaration.

Previous: , Up: Glibc Extensions to <pthread.h>   [Contents][Index]

14.38.19 pthread_tryjoin_np

Documentation:
man pthread_tryjoin_np

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.3.2, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.10.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.39 Glibc <pty.h>

Next: , Up: Glibc <pty.h>   [Contents][Index]

14.39.1 forkpty

Documentation:

Gnulib module: forkpty

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Android 5.1.
  • One some systems (at least including Cygwin and Mac OS X) linking with -lutil is not required.
  • On glibc, OpenBSD, NetBSD and FreeBSD linking with -lutil is required.
  • The function is declared in pty.h on glibc and Cygwin. It is declared in util.h on Mac OS X, OpenBSD, and NetBSD. It is declared in libutil.h on FreeBSD. It is declared in termios.h on Solaris.
  • Some platforms declare the function without marking the last two parameters const. FreeBSD 14.0, Solaris 11.4, Cygwin 1.7.1.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Previous: , Up: Glibc <pty.h>   [Contents][Index]

14.39.2 openpty

Documentation:

Gnulib module: openpty

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 11.3, Android 5.1.
  • One some systems (at least including Cygwin and Mac OS X) linking with -lutil is not required.
  • On glibc, OpenBSD, NetBSD and FreeBSD linking with -lutil is required.
  • The function is declared in pty.h on glibc and Cygwin. It is declared in util.h on Mac OS X, OpenBSD, and NetBSD. It is declared in libutil.h on FreeBSD. It is declared in termios.h on Solaris.
  • Some platforms declare the function without marking the last two parameters const. FreeBSD 14.0, Solaris 11.4, Cygwin 1.7.1.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.40 Glibc Extensions to <pwd.h>

Next: , Up: Glibc Extensions to <pwd.h>   [Contents][Index]

14.40.1 fgetpwent

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <pwd.h>   [Contents][Index]

14.40.2 fgetpwent_r

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <pwd.h>   [Contents][Index]

14.40.3 getpw

Documentation:
man getpw

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <pwd.h>   [Contents][Index]

14.40.4 getpwent_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getpwent-r-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc Extensions to <pwd.h>   [Contents][Index]

14.40.5 putpwent

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.41 Glibc Extensions to <regex.h>

Next: , Up: Glibc Extensions to <regex.h>   [Contents][Index]

14.41.1 re_comp

Documentation:
man re_comp

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <regex.h>   [Contents][Index]

14.41.2 re_compile_fastmap

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <regex.h>   [Contents][Index]

14.41.3 re_compile_pattern

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <regex.h>   [Contents][Index]

14.41.4 re_exec

Documentation:
man re_exec

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <regex.h>   [Contents][Index]

14.41.5 re_match

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <regex.h>   [Contents][Index]

14.41.6 re_match_2

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <regex.h>   [Contents][Index]

14.41.7 re_search

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <regex.h>   [Contents][Index]

14.41.8 re_search_2

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <regex.h>   [Contents][Index]

14.41.9 re_set_registers

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <regex.h>   [Contents][Index]

14.41.10 re_set_syntax

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc Extensions to <regex.h>   [Contents][Index]

14.41.11 re_syntax_options

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.42 Glibc <regexp.h>

Next: , Up: Glibc <regexp.h>   [Contents][Index]

14.42.1 advance

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <regexp.h>   [Contents][Index]

14.42.2 loc1

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <regexp.h>   [Contents][Index]

14.42.3 loc2

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <regexp.h>   [Contents][Index]

14.42.4 locs

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <regexp.h>   [Contents][Index]

14.42.5 step

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.43 Glibc <resolv.h>

Next: , Up: Glibc <resolv.h>   [Contents][Index]

14.43.1 dn_comp

Documentation:
man dn_comp

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, OpenBSD 7.9, Minix 3.3.0, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <resolv.h>   [Contents][Index]

14.43.2 dn_expand

Documentation:
man dn_expand

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Cygwin 1.5.x, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <resolv.h>   [Contents][Index]

14.43.3 dn_skipname

Documentation:
man dn_skipname

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <resolv.h>   [Contents][Index]

14.43.4 res_dnok

Documentation:
man res_dnok

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <resolv.h>   [Contents][Index]

14.43.5 res_hnok

Documentation:
man res_hnok

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <resolv.h>   [Contents][Index]

14.43.6 res_init

Documentation:
man res_init

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Cygwin 1.5.x, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <resolv.h>   [Contents][Index]

14.43.7 res_mailok

Documentation:
man res_mailok

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <resolv.h>   [Contents][Index]

14.43.8 res_mkquery

Documentation:
man res_mkquery

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, Cygwin 1.5.x, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <resolv.h>   [Contents][Index]

14.43.9 res_nmkquery

Documentation:
man res_nmkquery

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.31, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <resolv.h>   [Contents][Index]

14.43.10 res_nquery

Documentation:
man res_nquery

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.31, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <resolv.h>   [Contents][Index]

14.43.11 res_nquerydomain

Documentation:
man res_nquerydomain

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.31, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <resolv.h>   [Contents][Index]

14.43.12 res_nsearch

Documentation:
man res_nsearch

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.31, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <resolv.h>   [Contents][Index]

14.43.13 res_nsend

Documentation:
man res_nsend

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.31, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <resolv.h>   [Contents][Index]

14.43.14 res_ownok

Documentation:
man res_ownok

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, HP-UX 11.11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <resolv.h>   [Contents][Index]

14.43.15 res_query

Documentation:
man res_query

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Cygwin 1.5.x, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <resolv.h>   [Contents][Index]

14.43.16 res_querydomain

Documentation:
man res_querydomain

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, Minix 3.3.0, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <resolv.h>   [Contents][Index]

14.43.17 res_search

Documentation:
man res_search

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Cygwin 1.5.x, mingw, MSVC 14.

Previous: , Up: Glibc <resolv.h>   [Contents][Index]

14.43.18 res_send

Documentation:
man res_send

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, OpenBSD 7.9, Minix 3.3.0, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.44 Glibc <rpc/auth.h>

Next: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.1 authdes_create

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.2 authdes_pk_create

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.3 authnone_create

Documentation:
man authnone_create

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.4 authunix_create

Documentation:
man authunix_create

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.5 authunix_create_default

Documentation:
man authunix_create_default

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.6 getnetname

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.7 host2netname

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.8 key_decryptsession

Documentation:
man key_decryptsession

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.9 key_decryptsession_pk

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.10 key_encryptsession

Documentation:
man key_encryptsession

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.11 key_encryptsession_pk

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.12 key_gendes

Documentation:
man key_gendes

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.13 key_get_conv

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.14 key_secretkey_is_set

Documentation:
man key_secretkey_is_set

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.15 key_setsecret

Documentation:
man key_setsecret

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.16 netname2host

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.17 netname2user

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.18 user2netname

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.19 xdr_des_block

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <rpc/auth.h>   [Contents][Index]

14.44.20 xdr_opaque_auth

Documentation:
man xdr_opaque_auth

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.45 Glibc <rpc/auth_des.h>

Next: , Up: Glibc <rpc/auth_des.h>   [Contents][Index]

14.45.1 authdes_getucred

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth_des.h>   [Contents][Index]

14.45.2 getpublickey

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/auth_des.h>   [Contents][Index]

14.45.3 getsecretkey

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <rpc/auth_des.h>   [Contents][Index]

14.45.4 rtime

Documentation:
man rtime

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.46 Glibc <rpc/auth_unix.h>

Up: Glibc <rpc/auth_unix.h>   [Contents][Index]

14.46.1 xdr_authunix_parms

Documentation:
man xdr_authunix_parms

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.47 Glibc <rpc/clnt.h>

Next: , Up: Glibc <rpc/clnt.h>   [Contents][Index]

14.47.1 callrpc

Documentation:
man callrpc

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/clnt.h>   [Contents][Index]

14.47.2 clnt_create

Documentation:
man clnt_create

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/clnt.h>   [Contents][Index]

14.47.3 clnt_pcreateerror

Documentation:
man clnt_pcreateerror

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/clnt.h>   [Contents][Index]

14.47.4 clnt_perrno

Documentation:
man clnt_perrno

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/clnt.h>   [Contents][Index]

14.47.5 clnt_perror

Documentation:
man clnt_perror

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/clnt.h>   [Contents][Index]

14.47.6 clnt_spcreateerror

Documentation:
man clnt_spcreateerror

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/clnt.h>   [Contents][Index]

14.47.7 clnt_sperrno

Documentation:
man clnt_sperrno

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/clnt.h>   [Contents][Index]

14.47.8 clnt_sperror

Documentation:
man clnt_sperror

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/clnt.h>   [Contents][Index]

14.47.9 clntraw_create

Documentation:
man clntraw_create

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/clnt.h>   [Contents][Index]

14.47.10 clnttcp_create

Documentation:
man clnttcp_create

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/clnt.h>   [Contents][Index]

14.47.11 clntudp_bufcreate

Documentation:
man clntudp_bufcreate

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/clnt.h>   [Contents][Index]

14.47.12 clntudp_create

Documentation:
man clntudp_create

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/clnt.h>   [Contents][Index]

14.47.13 clntunix_create

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/clnt.h>   [Contents][Index]

14.47.14 get_myaddress

Documentation:
man get_myaddress

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/clnt.h>   [Contents][Index]

14.47.15 getrpcport

Documentation:
man getrpcport

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <rpc/clnt.h>   [Contents][Index]

14.47.16 rpc_createerr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on some platforms: Minix 3.1.8, AIX 5.1, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.48 Glibc <rpc/key_prot.h>

Next: , Up: Glibc <rpc/key_prot.h>   [Contents][Index]

14.48.1 xdr_cryptkeyarg

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/key_prot.h>   [Contents][Index]

14.48.2 xdr_cryptkeyarg2

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/key_prot.h>   [Contents][Index]

14.48.3 xdr_cryptkeyres

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/key_prot.h>   [Contents][Index]

14.48.4 xdr_getcredres

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/key_prot.h>   [Contents][Index]

14.48.5 xdr_key_netstarg

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/key_prot.h>   [Contents][Index]

14.48.6 xdr_key_netstres

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/key_prot.h>   [Contents][Index]

14.48.7 xdr_keybuf

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/key_prot.h>   [Contents][Index]

14.48.8 xdr_keystatus

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/key_prot.h>   [Contents][Index]

14.48.9 xdr_netnamestr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <rpc/key_prot.h>   [Contents][Index]

14.48.10 xdr_unixcred

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.49 Glibc <rpc/netdb.h>

Next: , Up: Glibc <rpc/netdb.h>   [Contents][Index]

14.49.1 endrpcent

Documentation:
man endrpcent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/netdb.h>   [Contents][Index]

14.49.2 getrpcbyname

Documentation:
man getrpcbyname

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/netdb.h>   [Contents][Index]

14.49.3 getrpcbyname_r

Documentation:
man getrpcbyname_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/netdb.h>   [Contents][Index]

14.49.4 getrpcbynumber

Documentation:
man getrpcbynumber

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/netdb.h>   [Contents][Index]

14.49.5 getrpcbynumber_r

Documentation:
man getrpcbynumber_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/netdb.h>   [Contents][Index]

14.49.6 getrpcent

Documentation:
man getrpcent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/netdb.h>   [Contents][Index]

14.49.7 getrpcent_r

Documentation:
man getrpcent_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <rpc/netdb.h>   [Contents][Index]

14.49.8 setrpcent

Documentation:
man setrpcent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.50 Glibc <rpc/pmap_clnt.h>

Next: , Up: Glibc <rpc/pmap_clnt.h>   [Contents][Index]

14.50.1 clnt_broadcast

Documentation:
man clnt_broadcast

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/pmap_clnt.h>   [Contents][Index]

14.50.2 pmap_getmaps

Documentation:
man pmap_getmaps

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/pmap_clnt.h>   [Contents][Index]

14.50.3 pmap_getport

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-pmap-getport-3.html

Documentation:
man pmap_getport

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/pmap_clnt.h>   [Contents][Index]

14.50.4 pmap_rmtcall

Documentation:
man pmap_rmtcall

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/pmap_clnt.h>   [Contents][Index]

14.50.5 pmap_set

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-pmap-set-3.html

Documentation:
man pmap_set

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <rpc/pmap_clnt.h>   [Contents][Index]

14.50.6 pmap_unset

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-pmap-unset-3.html

Documentation:
man pmap_unset

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.51 Glibc <rpc/pmap_prot.h>

Next: , Up: Glibc <rpc/pmap_prot.h>   [Contents][Index]

14.51.1 xdr_pmap

Documentation:
man xdr_pmap

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <rpc/pmap_prot.h>   [Contents][Index]

14.51.2 xdr_pmaplist

Documentation:
man xdr_pmaplist

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.52 Glibc <rpc/pmap_rmt.h>

Next: , Up: Glibc <rpc/pmap_rmt.h>   [Contents][Index]

14.52.1 xdr_rmtcall_args

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <rpc/pmap_rmt.h>   [Contents][Index]

14.52.2 xdr_rmtcallres

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.53 Glibc <rpc/rpc_msg.h>

Next: , Up: Glibc <rpc/rpc_msg.h>   [Contents][Index]

14.53.1 xdr_callhdr

Documentation:
man xdr_callhdr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/rpc_msg.h>   [Contents][Index]

14.53.2 xdr_callmsg

Documentation:
man xdr_callmsg

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <rpc/rpc_msg.h>   [Contents][Index]

14.53.3 xdr_replymsg

Documentation:
man xdr_replymsg

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.54 Glibc <rpc/svc.h>

Next: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.1 svc_exit

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.2 svc_fdset

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.3 svc_getreq

Documentation:
man svc_getreq

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.4 svc_getreq_common

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, Minix 3.1.8, AIX 5.1, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.5 svc_getreq_poll

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.6 svc_getreqset

Documentation:
man svc_getreqset

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.7 svc_max_pollfd

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.8 svc_pollfd

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.9 svc_register

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-svc-register-3.html

Documentation:
man svc_register

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.10 svc_run

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-svc-run-3.html

Documentation:
man svc_run

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.11 svc_sendreply

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-svc-sendreply-3.html

Documentation:
man svc_sendreply

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.12 svc_unregister

Documentation:
man svc_unregister

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.13 svcerr_auth

Documentation:
man svcerr_auth

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.14 svcerr_decode

Documentation:
man svcerr_decode

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.15 svcerr_noproc

Documentation:
man svcerr_noproc

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.16 svcerr_noprog

Documentation:
man svcerr_noprog

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.17 svcerr_progvers

Documentation:
man svcerr_progvers

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.18 svcerr_systemerr

Documentation:
man svcerr_systemerr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.19 svcerr_weakauth

Documentation:
man svcerr_weakauth

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.20 svcraw_create

Documentation:
man svcraw_create

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.21 svctcp_create

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-svctcp-create-3.html

Documentation:
man svctcp_create

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.22 svcudp_bufcreate

Documentation:
man svcudp_bufcreate

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.23 svcudp_create

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-svcudp-create-3.html

Documentation:
man svcudp_create

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.24 svcunix_create

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.25 xprt_register

Documentation:
man xprt_register

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <rpc/svc.h>   [Contents][Index]

14.54.26 xprt_unregister

Documentation:
man xprt_unregister

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.55 Glibc <rpc/xdr.h>

Next: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.1 xdr_array

Documentation:
man xdr_array

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.2 xdr_bool

Documentation:
man xdr_bool

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.3 xdr_bytes

Documentation:
man xdr_bytes

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.4 xdr_char

Documentation:
man xdr_char

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.5 xdr_double

Documentation:
man xdr_double

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.6 xdr_enum

Documentation:
man xdr_enum

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.7 xdr_float

Documentation:
man xdr_float

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.8 xdr_free

Documentation:
man xdr_free

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.9 xdr_hyper

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.10 xdr_int

Documentation:
man xdr_int

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.11 xdr_int16_t

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.12 xdr_int32_t

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.13 xdr_int64_t

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.14 xdr_int8_t

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.15 xdr_long

Documentation:
man xdr_long

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.16 xdr_longlong_t

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.17 xdr_netobj

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.18 xdr_opaque

Documentation:
man xdr_opaque

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.19 xdr_pointer

Documentation:
man xdr_pointer

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.20 xdr_quad_t

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.21 xdr_reference

Documentation:
man xdr_reference

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.22 xdr_short

Documentation:
man xdr_short

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.23 xdr_sizeof

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.24 xdr_string

Documentation:
man xdr_string

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.25 xdr_u_char

Documentation:
man xdr_u_char

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.26 xdr_u_hyper

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.27 xdr_u_int

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-xdr-u-int-3.html

Documentation:
man xdr_u_int

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.28 xdr_u_long

Documentation:
man xdr_u_long

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.29 xdr_u_longlong_t

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.30 xdr_u_quad_t

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.31 xdr_u_short

Documentation:
man xdr_u_short

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.32 xdr_uint16_t

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.
  • This function is not declared in the header on some platforms: Cygwin 1.7.5.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.33 xdr_uint32_t

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function is not declared in the header on some platforms: Cygwin 1.7.5.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.34 xdr_uint64_t

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function is not declared in the header on some platforms: Cygwin 1.7.5.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.35 xdr_uint8_t

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function is not declared in the header on some platforms: Cygwin 1.7.5.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.36 xdr_union

Documentation:
man xdr_union

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.37 xdr_vector

Documentation:
man xdr_vector

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.38 xdr_void

Documentation:
man xdr_void

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.39 xdr_wrapstring

Documentation:
man xdr_wrapstring

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.40 xdrmem_create

Documentation:
man xdrmem_create

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.41 xdrrec_create

Documentation:
man xdrrec_create

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.42 xdrrec_endofrecord

Documentation:
man xdrrec_endofrecord

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.43 xdrrec_eof

Documentation:
man xdrrec_eof

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.44 xdrrec_skiprecord

Documentation:
man xdrrec_skiprecord

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <rpc/xdr.h>   [Contents][Index]

14.55.45 xdrstdio_create

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-xdrstdio-create-3.html

Documentation:
man xdrstdio_create

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.56 Glibc <rpcsvc/nislib.h>

Next: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.1 nis_add

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.2 nis_add_entry

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.3 nis_addmember

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.4 nis_checkpoint

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.5 nis_clone_object

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.6 nis_creategroup

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.7 nis_destroy_object

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.8 nis_destroygroup

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.9 nis_dir_cmp

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.10 nis_domain_of

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.11 nis_domain_of_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.12 nis_first_entry

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.13 nis_freenames

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.14 nis_freeresult

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.15 nis_freeservlist

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.16 nis_freetags

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.17 nis_getnames

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.18 nis_getservlist

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.19 nis_ismember

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.20 nis_leaf_of

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.21 nis_leaf_of_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.22 nis_lerror

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.23 nis_list

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.24 nis_local_directory

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.25 nis_local_group

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.26 nis_local_host

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.27 nis_local_principal

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.28 nis_lookup

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.29 nis_mkdir

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.30 nis_modify

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.31 nis_modify_entry

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.32 nis_name_of

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.33 nis_name_of_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.34 nis_next_entry

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.35 nis_perror

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.36 nis_ping

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.37 nis_print_directory

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.38 nis_print_entry

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.39 nis_print_group

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.40 nis_print_group_entry

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.42 nis_print_object

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.43 nis_print_result

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.44 nis_print_rights

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.45 nis_print_table

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.46 nis_remove

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.47 nis_remove_entry

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.48 nis_removemember

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.49 nis_rmdir

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.50 nis_servstate

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.51 nis_sperrno

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.52 nis_sperror

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.53 nis_sperror_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.54 nis_stats

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <rpcsvc/nislib.h>   [Contents][Index]

14.56.55 nis_verifygroup

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.57 Glibc <rpcsvc/nis_callback.h>

Next: , Up: Glibc <rpcsvc/nis_callback.h>   [Contents][Index]

14.57.1 xdr_cback_data

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <rpcsvc/nis_callback.h>   [Contents][Index]

14.57.2 xdr_obj_p

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.58 Glibc <rpcsvc/yp.h>

Next: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.1 xdr_domainname

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.2 xdr_keydat

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 5.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.3 xdr_valdat

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 5.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.4 xdr_ypbind_resptype

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 5.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.5 xdr_ypmap_parms

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, OpenBSD 3.8, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.6 xdr_ypmaplist

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.7 xdr_yppushresp_xfr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, OpenBSD 3.8, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.8 xdr_ypreq_key

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.9 xdr_ypreq_nokey

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.10 xdr_ypreq_xfr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, OpenBSD 3.8, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.11 xdr_ypresp_all

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 5.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.12 xdr_ypresp_key_val

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.13 xdr_ypresp_maplist

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.14 xdr_ypresp_master

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.15 xdr_ypresp_order

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.16 xdr_ypresp_val

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.17 xdr_ypresp_xfr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.18 xdr_ypstat

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 5.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <rpcsvc/yp.h>   [Contents][Index]

14.58.19 xdr_ypxfrstat

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.59 Glibc <rpcsvc/ypclnt.h>

Next: , Up: Glibc <rpcsvc/ypclnt.h>   [Contents][Index]

14.59.1 yp_all

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/ypclnt.h>   [Contents][Index]

14.59.2 yp_bind

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/ypclnt.h>   [Contents][Index]

14.59.3 yp_first

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/ypclnt.h>   [Contents][Index]

14.59.4 yp_get_default_domain

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/ypclnt.h>   [Contents][Index]

14.59.5 yp_master

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/ypclnt.h>   [Contents][Index]

14.59.6 yp_match

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/ypclnt.h>   [Contents][Index]

14.59.7 yp_next

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/ypclnt.h>   [Contents][Index]

14.59.8 yp_order

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/ypclnt.h>   [Contents][Index]

14.59.9 yp_unbind

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/ypclnt.h>   [Contents][Index]

14.59.10 ypbinderr_string

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <rpcsvc/ypclnt.h>   [Contents][Index]

14.59.11 yperr_string

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <rpcsvc/ypclnt.h>   [Contents][Index]

14.59.12 ypprot_err

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.60 Glibc Extensions to <sched.h>

Next: , Up: Glibc Extensions to <sched.h>   [Contents][Index]

14.60.1 clone

Documentation:
man clone

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <sched.h>   [Contents][Index]

14.60.2 getcpu

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on all non-glibc platforms: glibc 2.28, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <sched.h>   [Contents][Index]

14.60.3 sched_getaffinity

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-sched-getaffinity.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 13.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 3.0.x, mingw, MSVC 14, Android 3.0.

Next: , Previous: , Up: Glibc Extensions to <sched.h>   [Contents][Index]

14.60.4 sched_getattr

Documentation:
man sched_getattr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on most non-glibc platforms: glibc 2.40, macOS 14, FreeBSD 13.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.10.x, mingw, MSVC 14, Android API level 36.

Next: , Previous: , Up: Glibc Extensions to <sched.h>   [Contents][Index]

14.60.5 sched_getcpu

Documentation:
man sched_getcpu

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and Cygwin and is therefore missing on most non-glibc platforms: glibc 2.5, macOS 14, FreeBSD 13.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.10.x, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <sched.h>   [Contents][Index]

14.60.6 sched_setaffinity

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-sched-setaffinity.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 13.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 3.0.x, mingw, MSVC 14, Android 3.0.

Next: , Previous: , Up: Glibc Extensions to <sched.h>   [Contents][Index]

14.60.7 sched_setattr

Documentation:
man sched_setattr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on most non-glibc platforms: glibc 2.40, macOS 14, FreeBSD 13.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.10.x, mingw, MSVC 14, Android API level 36.

Previous: , Up: Glibc Extensions to <sched.h>   [Contents][Index]

14.60.8 setns

Documentation:
man setns

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.13, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.61 Glibc Extensions to <search.h>

Next: , Up: Glibc Extensions to <search.h>   [Contents][Index]

14.61.1 hcreate_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-hcreate-r.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Glibc Extensions to <search.h>   [Contents][Index]

14.61.2 hdestroy_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-hdestroy-r.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Glibc Extensions to <search.h>   [Contents][Index]

14.61.3 hsearch_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-hsearch-r.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Glibc Extensions to <search.h>   [Contents][Index]

14.61.4 tdestroy

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.0, mingw, MSVC 14, Android 4.0.4.

Previous: , Up: Glibc Extensions to <search.h>   [Contents][Index]

14.61.5 twalk_r

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.62 Glibc Extensions to <selinux/selinux.h>

Next: , Up: Glibc Extensions to <selinux/selinux.h>   [Contents][Index]

14.62.1 fgetfilecon

Documentation:
man fgetfilecon

Gnulib module: selinux-h

Portability problems fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0. On those platforms, this module provides a stub that always sets errno to ENOTSUP and returns ‘-1’.
  • On systems with SELinux support, this module provides a wrapper for the fgetfilecon function that insulates the caller from API-nonconforming behavior. Without this wrapper, fgetfilecon can return ‘0’ and set the context pointer to NULL, and in another scenario can return ‘10’ and set the context pointer to ‘unlabeled’. This wrapper returns ‘-1’ in each case and sets errno to ENOTSUP and ENODATA respectively. While the conditions that can provoke such behavior are rare, the average caller does not handle them because the possibility of such behavior is not documented.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <selinux/selinux.h>   [Contents][Index]

14.62.2 getfilecon

Documentation:
man getfilecon

Gnulib module: selinux-h

Portability problems fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0. On those platforms, this module provides a stub that always sets errno to ENOTSUP and returns ‘-1’.
  • On systems with SELinux support, this module provides a wrapper for the getfilecon function that insulates the caller from API-nonconforming behavior. Without this wrapper, getfilecon can return ‘0’ and set the context pointer to NULL, and in another scenario can return ‘10’ and set the context pointer to ‘unlabeled’. This wrapper returns ‘-1’ in each case and sets errno to ENOTSUP and ENODATA respectively. While the conditions that can provoke such behavior are rare, the average caller does not handle them because the possibility of such behavior is not documented.

Portability problems not fixed by Gnulib:

Previous: , Up: Glibc Extensions to <selinux/selinux.h>   [Contents][Index]

14.62.3 lgetfilecon

Documentation:
man lgetfilecon

Gnulib module: selinux-h

Portability problems fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0. On those platforms, this module provides a stub that always sets errno to ENOTSUP and returns ‘-1’.
  • On systems with SELinux support, this module provides a wrapper for the lgetfilecon function that insulates the caller from API-nonconforming behavior. Without this wrapper, lgetfilecon can return ‘0’ and set the context pointer to NULL, and in another scenario can return ‘10’ and set the context pointer to ‘unlabeled’. This wrapper returns ‘-1’ in each case and sets errno to ENOTSUP and ENODATA respectively. While the conditions that can provoke such behavior are rare, the average caller does not handle them because the possibility of such behavior is not documented.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.63 Glibc <shadow.h>

Next: , Up: Glibc <shadow.h>   [Contents][Index]

14.63.1 endspent

Documentation:
man endspent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <shadow.h>   [Contents][Index]

14.63.2 fgetspent

Documentation:
man fgetspent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <shadow.h>   [Contents][Index]

14.63.3 fgetspent_r

Documentation:
man fgetspent_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <shadow.h>   [Contents][Index]

14.63.4 getspent

Documentation:
man getspent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <shadow.h>   [Contents][Index]

14.63.5 getspent_r

Documentation:
man getspent_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <shadow.h>   [Contents][Index]

14.63.6 getspnam

Documentation:
man getspnam

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <shadow.h>   [Contents][Index]

14.63.7 getspnam_r

Documentation:
man getspnam_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <shadow.h>   [Contents][Index]

14.63.8 lckpwdf

Documentation:
man lckpwdf

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <shadow.h>   [Contents][Index]

14.63.9 putspent

Documentation:
man putspent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <shadow.h>   [Contents][Index]

14.63.10 setspent

Documentation:
man setspent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <shadow.h>   [Contents][Index]

14.63.11 sgetspent

Documentation:
man sgetspent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <shadow.h>   [Contents][Index]

14.63.12 sgetspent_r

Documentation:
man sgetspent_r

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <shadow.h>   [Contents][Index]

14.63.13 ulckpwdf

Documentation:
man ulckpwdf

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.64 Glibc Extensions to <signal.h>

Next: , Up: Glibc Extensions to <signal.h>   [Contents][Index]

14.64.1 gsignal

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <signal.h>   [Contents][Index]

14.64.2 sigandset

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-sigandset.html

Documentation:
man sigandset

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 12.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <signal.h>   [Contents][Index]

14.64.3 sigblock

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <signal.h>   [Contents][Index]

14.64.4 siggetmask

Documentation:
man siggetmask

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <signal.h>   [Contents][Index]

14.64.5 sigisemptyset

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-sigisemptyset.html

Documentation:
man sigisemptyset

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 12.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <signal.h>   [Contents][Index]

14.64.6 sigorset

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-sigorset.html

Documentation:
man sigorset

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 12.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <signal.h>   [Contents][Index]

14.64.7 sigreturn

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-sigreturn-2.html

Documentation:
man sigreturn

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <signal.h>   [Contents][Index]

14.64.8 sigsetmask

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <signal.h>   [Contents][Index]

14.64.9 sigstack

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <signal.h>   [Contents][Index]

14.64.10 sigvec

Documentation:
man sigvec

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <signal.h>   [Contents][Index]

14.64.11 ssignal

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <signal.h>   [Contents][Index]

14.64.12 sys_siglist

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Signal-Messages.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This constant is missing on some platforms: Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 1.7.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <signal.h>   [Contents][Index]

14.64.13 sysv_signal

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc Extensions to <signal.h>   [Contents][Index]

14.64.14 tgkill

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on most non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.65 Glibc Extensions to <spawn.h>

Next: , Up: Glibc Extensions to <spawn.h>   [Contents][Index]

14.65.1 pidfd_spawn

Documentation:
https://lwn.net/Articles/943022/

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Glibc Extensions to <spawn.h>   [Contents][Index]

14.65.2 pidfd_spawnp

Documentation:
https://lwn.net/Articles/943022/

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Glibc Extensions to <spawn.h>   [Contents][Index]

14.65.3 posix_spawn_file_actions_addchdir_np

posix_spawn_file_actions_addchdir is specified in POSIX.1-2024. Draft specification:
https://www.austingroupbugs.net/view.php?id=1208

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.28, macOS 10.14, FreeBSD 13.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.0, Cygwin 3.4.x, mingw, MSVC 14, Android API level 33.

Note: Gnulib has a module posix_spawn_file_actions_addchdir that provides equivalent functionality, just without the suffix _np.

Next: , Previous: , Up: Glibc Extensions to <spawn.h>   [Contents][Index]

14.65.4 posix_spawn_file_actions_addclosefrom_np

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.33, macOS 14, FreeBSD 13.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.1, HP-UX 11.31, Solaris 10, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <spawn.h>   [Contents][Index]

14.65.5 posix_spawn_file_actions_addfchdir_np

posix_spawn_file_actions_addfchdir is specified in POSIX.1-2024. Draft specification:
https://www.austingroupbugs.net/view.php?id=1208

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.28, macOS 10.14, FreeBSD 13.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.4.x, mingw, MSVC 14, Android API level 33.

Note: Gnulib has a module posix_spawn_file_actions_addfchdir that provides equivalent functionality, just without the suffix _np.

Next: , Previous: , Up: Glibc Extensions to <spawn.h>   [Contents][Index]

14.65.6 posix_spawn_file_actions_addtcsetpgrp_np

Documentation: —

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android.

Next: , Previous: , Up: Glibc Extensions to <spawn.h>   [Contents][Index]

14.65.7 posix_spawnattr_getcgroup_np

Documentation:
https://sourceware.org/pipermail/libc-alpha/2023-August/151106.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Previous: , Up: Glibc Extensions to <spawn.h>   [Contents][Index]

14.65.8 posix_spawnattr_setcgroup_np

Documentation:
https://sourceware.org/pipermail/libc-alpha/2023-August/151106.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.66 Glibc Extensions to <stdio.h>

Next: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.1 cuserid

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.2 clearerr_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-clearerr-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 5.1.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.3 fcloseall

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, mingw, Android 9.0.
  • This functions returns void instead of int on some platforms: FreeBSD 14.0.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.4 feof_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-feof-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 5.1.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.5 ferror_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-ferror-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 5.1.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.6 fflush_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fflush-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 12.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.7 fgetc_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fgetc-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.8 fgets_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fgets-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.9 fileno_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fileno-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 6.0.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.10 fopencookie

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 10.4, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.3, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.11 fputc_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fputc-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 12.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.12 fputs_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fputs-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 12.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.13 fread_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fread-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 12.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.14 fwrite_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fwrite-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 12.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.15 getw

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.16 putw

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is not declared on some platforms: Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.17 renameat2

Documentation:
man renameat2

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.8.x, mingw, MSVC 14, Android API level 29.
  • This function succeeds when the RENAME_NOREPLACE flag is specified and the source and destination are the same file, on some platforms: Cygwin 3.4.6.
  • renameat2 (AT_FDCWD, "file", AT_FDCWD, "new/" ...) succeeds instead of failing and setting errno to ENOTDIR, on some platforms: GNU/Hurd with glibc 2.41.
  • renameat2 (ATFDCWD, "dir", AT_FDCWD, "new/" ...) fails with errno set to ENOENT, on some platforms: GNU/Hurd with glibc 2.42.
  • renameat2 (ATFDCWD, "dir/", AT_FDCWD, "new" ...) fails with errno set to ENOTDIR, on some platforms: GNU/Hurd with glibc 2.42.

The renameatu module addresses some of these portability issues.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.18 setbuffer

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-setbuffer-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.19 setlinebuf

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.23, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.20 sys_errlist

Documentation:
man sys_errlist

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.21 sys_nerr

Documentation:
man sys_nerr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on some platforms: Minix 3.1.8, Cygwin 2.9, mingw, Android 9.0.

Previous: , Up: Glibc Extensions to <stdio.h>   [Contents][Index]

14.66.22 tmpnam_r

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.67 Glibc Extensions to <stdlib.h>

Next: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.1 arc4random

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.35, AIX 7.3.1, HP-UX 11.31, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.2 arc4random_buf

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.35, AIX 7.3.1, HP-UX 11.31, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.3 arc4random_uniform

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.35, AIX 7.3.1, HP-UX 11.31, Solaris 11.3, Cygwin 1.7.x, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.4 canonicalize_file_name

Documentation:

Gnulib module: canonicalize-lgpl

Portability problems fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.
  • This function fails to detect trailing slashes on non-directories on some platforms: glibc 2.3.5.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.5 cfree

Documentation:
man cfree

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.6 clearenv

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 13.2, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, Solaris 10, Cygwin 2.10.x, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.7 drand48_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-drand48-r-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.3, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.8 ecvt_r

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.9 erand48_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-erand48-r-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.3, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.10 fcvt_r

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.11 getloadavg

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getloadavg-3.html

Documentation:

Gnulib module: getloadavg

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.
  • This function is declared in <sys/loadavg.h>, not <stdlib.h>, on some platforms: Solaris 11.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.12 getpt

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.13 initstate_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-initstate-r-1.html

Documentation:

Gnulib module: random_r

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function has an incompatible declaration on some platforms: AIX 7.1.

Portability problems not fixed by Gnulib:

  • This function crashes if the state buffer is unaligned on some platforms: glibc 2.40/sparc.
  • This function has a slightly different (but compatible) declaration on some platforms: Haiku.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.14 jrand48_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-jrand48-r-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.3, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.15 lcong48_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-lcong48-r-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.3, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.16 lrand48_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-lrand48-r-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.3, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.17 mkostemps

Documentation:
man mkostemps

Gnulib module: mkostemps

Portability problems fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.10, Mac OS X 10.5, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.5, mingw, MSVC 14, Android 5.1.
  • This function is declared in <unistd.h> instead of <stdlib.h> on some platforms: macOS 14.
  • On platforms where off_t is a 32-bit type, mkostemps may not work correctly to create files larger than 2 GB. (Cf. AC_SYS_LARGEFILE.)

Portability problems not fixed by Gnulib:

The gnulib module clean-temp can create temporary files that will not be left behind after signals such as SIGINT.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.18 mkstemps

Documentation:
man mkstemps

Gnulib module: mkstemps

Portability problems fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.10, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14.
  • This function is declared in <unistd.h> instead of <stdlib.h> on some platforms: macOS 14.
  • On platforms where off_t is a 32-bit type, mkstemps may not work correctly to create files larger than 2 GB. (Cf. AC_SYS_LARGEFILE.)

Portability problems not fixed by Gnulib:

The gnulib module clean-temp can create temporary files that will not be left behind after signals such as SIGINT.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.19 mrand48_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-mrand48-r-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.3, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.20 nrand48_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-nrand48-r-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.3, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.21 on_exit

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.22 qecvt

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.23 qecvt_r

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.24 qfcvt

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.25 qfcvt_r

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.26 qgcvt

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.27 random_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-random-r-1.html

Documentation:

Gnulib module: random_r

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function has an incompatible declaration on some platforms: AIX 7.1.

Portability problems not fixed by Gnulib:

  • This function has a slightly different (but compatible) declaration on some platforms: Haiku 2017.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.28 rpmatch

Documentation:

Gnulib module: rpmatch

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 10.14, FreeBSD 5.2.1, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.29 seed48_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-seed48-r-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.3, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.30 setstate_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-setstate-r-1.html

Documentation:

Gnulib module: random_r

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • This function has an incompatible declaration on some platforms: AIX 7.1.

Portability problems not fixed by Gnulib:

  • This function has a slightly different (but compatible) declaration on some platforms: Haiku.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.31 srand48_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-srand48-r-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.3, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.32 srandom_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-srandom-r-1.html

Documentation:

Gnulib module: random_r

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.33 strtod_l

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.34 strtof_l

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.35 strtol_l

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.36 strtold_l

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.37 strtoll_l

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.38 strtoq

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-strtoq-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.
  • This function is not declared on some platforms: Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.39 strtoul_l

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.40 strtoull_l

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.41 strtouq

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-strtouq-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.
  • This function is not declared on some platforms: Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.42 uabs

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on most platforms: glibc 2.41, macOS 15, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.7, Minix, AIX 7.3, HP-UX 11.31, Solaris 11.4, Cygwin, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.43 ulabs

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on most platforms: glibc 2.41, macOS 15, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.7, Minix, AIX 7.3, HP-UX 11.31, Solaris 11.4, Cygwin, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.44 ullabs

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on most platforms: glibc 2.41, macOS 15, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.7, Minix, AIX 7.3, HP-UX 11.31, Solaris 11.4, Cygwin, mingw, MSVC 14.

Previous: , Up: Glibc Extensions to <stdlib.h>   [Contents][Index]

14.67.45 valloc

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.68 Glibc Extensions to <string.h>

Next: , Up: Glibc Extensions to <string.h>   [Contents][Index]

14.68.1 explicit_bzero

Documentation:

Gnulib module: explicit_bzero

The explicit_bzero function is an approximation to what is needed, and does not suffice in general to erase information. Although calling explicit_bzero should clear the memory in question, the information that was in memory may still be available elsewhere on the machine. Proper implementation of information erasure requires support from levels below C code.

C23 specifies the function memset_explicit, which should be preferred to explicit_bzero in new code. See memset_explicit.

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.24, FreeBSD 10, NetBSD 7.1, OpenBSD 5.4, macOS 10.12, Solaris 11.4, Android 9.0, and many other systems.

Portability problems not fixed by Gnulib:

  • Although the module’s implementation should clear the memory on platforms compatible with GCC and on platforms using traditional linkers, it may not clear the memory on non-GCC platforms that use whole-program optimization.

Next: , Previous: , Up: Glibc Extensions to <string.h>   [Contents][Index]

14.68.2 memfrob

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <string.h>   [Contents][Index]

14.68.3 mempcpy

Documentation:

Gnulib module: mempcpy

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 13.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 5.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <string.h>   [Contents][Index]

14.68.4 memrchr

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-memrchr.html

Documentation:

Gnulib module: memrchr

Portability problems fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 6.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <string.h>   [Contents][Index]

14.68.5 rawmemchr

Documentation:

Gnulib module: rawmemchr

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <string.h>   [Contents][Index]

14.68.6 sigabbrev_np

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Signal-Messages.html.

Gnulib module: sigabbrev_np

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.31, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Note: Gnulib has a module sig2str that contains an equivalent function and also one that does the opposite conversion, from an abbreviated signal name to a signal number.

Next: , Previous: , Up: Glibc Extensions to <string.h>   [Contents][Index]

14.68.7 sigdescr_np

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Signal-Messages.html.

Gnulib module: sigdescr_np

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.31, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

  • The description of SIGCHLD is wrong on some platforms: glibc.
  • The description of SIGEMT is completely unintelligible on some platforms: glibc.

Note: This function is hardly useful, because it returns English strings, not internationalized strings. Better use the function strsignal, which returns internationalized strings.

Next: , Previous: , Up: Glibc Extensions to <string.h>   [Contents][Index]

14.68.8 strcasestr

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-strcasestr.html

Documentation:

Gnulib module: strcasestr or strcasestr-simple

Portability problems fixed by either Gnulib module strcasestr-simple or strcasestr:

  • This function is missing on some platforms: AIX 7.2, HP-UX 11, Solaris 10, Cygwin 1.5.x, mingw, MSVC 14.
  • This function can trigger memchr bugs on some platforms: glibc 2.10.
  • This function can trigger false positives for long periodic needles on some platforms: glibc 2.12, Cygwin 1.7.7.
  • This function may fail to find matches on some platforms: glibc 2.28.

Portability problems fixed by Gnulib module strcasestr:

  • This function has quadratic instead of linear worst-case complexity on some platforms: glibc 2.8, musl libc 1.2.3, macOS 14, FreeBSD 13.1, NetBSD 10.0, OpenBSD 7.2, Solaris 11.4.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <string.h>   [Contents][Index]

14.68.9 strchrnul

Documentation:

Gnulib module: strchrnul

Portability problems fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 15.3, FreeBSD 6.0, NetBSD 7.1, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.7.8, mingw, MSVC 14, Android 6.0.
  • This function crashes when no occurrence is found on some platforms: Cygwin 1.7.9.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <string.h>   [Contents][Index]

14.68.10 strerrordesc_np

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Error-Messages.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.31, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <string.h>   [Contents][Index]

14.68.11 strerrorname_np

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Error-Messages.html.

Gnulib module: strerrorname_np

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.31, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android API level 34.
  • This function returns wrong values on some platforms: glibc 2.37, Solaris 11 OmniOS.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <string.h>   [Contents][Index]

14.68.12 strfry

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <string.h>   [Contents][Index]

14.68.13 strsep

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-strsep-3.html

Documentation:

Gnulib module: strsep

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11, Solaris 10, mingw, MSVC 14.

Portability problems not fixed by Gnulib:

Previous: , Up: Glibc Extensions to <string.h>   [Contents][Index]

14.68.14 strverscmp

Documentation:

Gnulib module: strverscmp

Portability problems fixed by Gnulib:

  • This function is missing on many platforms: macOS 14, FreeBSD 13.1, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.
  • This function treats ASCII letters as smaller than a digit sequence on some platforms: musl libc 1.2.3, Cygwin 3.4.x.

Portability problems not fixed by Gnulib:

  • On older glibc platforms, this function does not always properly treat digit strings with leading zeros as fractions (for example, strverscmp ("B0075022800016.gbp.corp.com", "B007502357019.GBP.CORP.COM") does not yield a negative number as it should): glibc 2.9

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.69 Glibc <sys/auxv.h>

Up: Glibc <sys/auxv.h>   [Contents][Index]

14.69.1 getauxval

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.15, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.70 Glibc <sys/capability.h>

Next: , Up: Glibc <sys/capability.h>   [Contents][Index]

14.70.1 capget

Documentation:
man capget

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Previous: , Up: Glibc <sys/capability.h>   [Contents][Index]

14.70.2 capset

Documentation:
man capset

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.71 Glibc <sys/epoll.h>

Next: , Up: Glibc <sys/epoll.h>   [Contents][Index]

14.71.1 epoll_create

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-epoll-create-1.html

Documentation:
man epoll_create

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and illumos and is therefore missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <sys/epoll.h>   [Contents][Index]

14.71.2 epoll_create1

Documentation:
man epoll_create1

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and illumos and is therefore missing on many non-glibc platforms: glibc 2.8, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 4.3.

Next: , Previous: , Up: Glibc <sys/epoll.h>   [Contents][Index]

14.71.3 epoll_ctl

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-epoll-ctl-1.html

Documentation:
man epoll_ctl

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and illumos and is therefore missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <sys/epoll.h>   [Contents][Index]

14.71.4 epoll_pwait

Documentation:
man epoll_pwait

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and illumos and is therefore missing on many non-glibc platforms: glibc 2.5, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 4.3.

Next: , Previous: , Up: Glibc <sys/epoll.h>   [Contents][Index]

14.71.5 epoll_pwait2

Documentation:
man epoll_pwait2

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.34, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android API level 34.

Previous: , Up: Glibc <sys/epoll.h>   [Contents][Index]

14.71.6 epoll_wait

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-epoll-wait-1.html

Documentation:
man epoll_wait

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and illumos and is therefore missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.72 Glibc <sys/eventfd.h>

Next: , Up: Glibc <sys/eventfd.h>   [Contents][Index]

14.72.1 eventfd

Documentation:
man eventfd

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux, FreeBSD, NetBSD, and illumos and is therefore missing on many non-glibc platforms: glibc 2.6, macOS 14, FreeBSD 12.0, NetBSD 9.3, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <sys/eventfd.h>   [Contents][Index]

14.72.2 eventfd_read

Documentation:
man eventfd_read

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux, FreeBSD, NetBSD, and illumos and is therefore missing on many non-glibc platforms: glibc 2.6, macOS 14, FreeBSD 12.0, NetBSD 9.3, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Previous: , Up: Glibc <sys/eventfd.h>   [Contents][Index]

14.72.3 eventfd_write

Documentation:
man eventfd_write

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux, FreeBSD, NetBSD, and illumos and is therefore missing on many non-glibc platforms: glibc 2.6, macOS 14, FreeBSD 12.0, NetBSD 9.3, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.73 Glibc <sys/fanotify.h>

Next: , Up: Glibc <sys/fanotify.h>   [Contents][Index]

14.73.1 fanotify_init

Documentation:
man fanotify_init

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on all non-glibc platforms: glibc 2.12, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <sys/fanotify.h>   [Contents][Index]

14.73.2 fanotify_mark

Documentation:
man fanotify_mark

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on all non-glibc platforms: glibc 2.12, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.74 Glibc <sys/file.h>

Up: Glibc <sys/file.h>   [Contents][Index]

14.74.1 flock

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-flock-2.html

Documentation:
man flock

Gnulib module: flock

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14
  • This function is missing on some platforms: AIX 7.1, HP-UX 11.23, Solaris 11.4. But the replacement function does not really work; it exhibits test failures.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.75 Glibc <sys/fsuid.h>

Next: , Up: Glibc <sys/fsuid.h>   [Contents][Index]

14.75.1 setfsgid

Documentation:
man setfsgid

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 4.4.

Previous: , Up: Glibc <sys/fsuid.h>   [Contents][Index]

14.75.2 setfsuid

Documentation:
man setfsuid

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.76 Glibc <sys/gmon.h>

Up: Glibc <sys/gmon.h>   [Contents][Index]

14.76.1 monstartup

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.77 Glibc <sys/inotify.h>

Next: , Up: Glibc <sys/inotify.h>   [Contents][Index]

14.77.1 inotify_add_watch

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-inotify-add-watch.html

Documentation:
man inotify_add_watch

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on most non-glibc platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <sys/inotify.h>   [Contents][Index]

14.77.2 inotify_init

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-inotify-init.html

Documentation:
man inotify_init

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on most non-glibc platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <sys/inotify.h>   [Contents][Index]

14.77.3 inotify_init1

Documentation:
man inotify_init1

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on most non-glibc platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 4.3.

Previous: , Up: Glibc <sys/inotify.h>   [Contents][Index]

14.77.4 inotify_rm_watch

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-inotify-rm-watch.html

Documentation:
man inotify_rm_watch

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on most non-glibc platforms: glibc 2.3.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.78 Glibc <sys/io.h>, <sys/perm.h>

Next: , Up: Glibc <sys/io.h>, <sys/perm.h>   [Contents][Index]

14.78.1 ioperm

Documentation:
man ioperm

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <sys/io.h>, <sys/perm.h>   [Contents][Index]

14.78.2 iopl

Documentation:
man iopl

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.79 Glibc <sys/kdaemon.h>

Up: Glibc <sys/kdaemon.h>   [Contents][Index]

14.79.1 bdflush

Documentation:
man bdflush

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.80 Glibc <sys/klog.h>

Up: Glibc <sys/klog.h>   [Contents][Index]

14.80.1 klogctl

Documentation:
man klogctl

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.81 Glibc Extensions to <sys/mman.h>

Next: , Up: Glibc Extensions to <sys/mman.h>   [Contents][Index]

14.81.1 madvise

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Cygwin 1.7.7, mingw, MSVC 14.
  • On Solaris 10 this function accepts char * not void *, unless you define feature test macros like _POSIX_C_SOURCE or _XOPEN_SOURCE that may undesirably hide other symbols. To work around this problem, callers can limit themselves to either void * or char *.

Next: , Previous: , Up: Glibc Extensions to <sys/mman.h>   [Contents][Index]

14.81.2 memfd_create

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and FreeBSD and is therefore missing on many non-glibc platforms: glibc 2.26, macOS 14, FreeBSD 12.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android API level 29.

Next: , Previous: , Up: Glibc Extensions to <sys/mman.h>   [Contents][Index]

14.81.3 mincore

Documentation:
man mincore

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14.
  • On Solaris 10 this function accepts char * not void *, unless you define feature test macros like _POSIX_C_SOURCE or _XOPEN_SOURCE that may undesirably hide other symbols. To work around this problem, callers can limit themselves to either void * or char *.

Next: , Previous: , Up: Glibc Extensions to <sys/mman.h>   [Contents][Index]

14.81.4 mlock2

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many platforms: glibc 2.26, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android API level 29.

Next: , Previous: , Up: Glibc Extensions to <sys/mman.h>   [Contents][Index]

14.81.5 mremap

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-mremap.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: macOS 14, FreeBSD 14.0, NetBSD 3.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <sys/mman.h>   [Contents][Index]

14.81.6 pkey_alloc

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on all non-glibc platforms: glibc 2.26, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <sys/mman.h>   [Contents][Index]

14.81.7 pkey_free

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on all non-glibc platforms: glibc 2.26, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <sys/mman.h>   [Contents][Index]

14.81.8 pkey_get

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Memory-Protection.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on all non-glibc platforms: glibc 2.26, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <sys/mman.h>   [Contents][Index]

14.81.9 pkey_mprotect

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on all non-glibc platforms: glibc 2.26, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <sys/mman.h>   [Contents][Index]

14.81.10 pkey_set

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Memory-Protection.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on all non-glibc platforms: glibc 2.26, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <sys/mman.h>   [Contents][Index]

14.81.11 process_madvise

Documentation:
man process_madvise

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.35, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Glibc Extensions to <sys/mman.h>   [Contents][Index]

14.81.12 process_mrelease

Documentation:
https://lwn.net/Articles/864184/

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.35, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Previous: , Up: Glibc Extensions to <sys/mman.h>   [Contents][Index]

14.81.13 remap_file_pages

Documentation:
man remap_file_pages

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.82 Glibc <sys/mount.h>

Next: , Up: Glibc <sys/mount.h>   [Contents][Index]

14.82.1 fsconfig

Documentation:
https://lore.kernel.org/all/159827191245.306468.4903071494263813779.stgit@warthog.procyon.org.uk/

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.35, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Glibc <sys/mount.h>   [Contents][Index]

14.82.2 fsmount

Documentation:
https://lore.kernel.org/all/159827190508.306468.12755090833140558156.stgit@warthog.procyon.org.uk/

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.35, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Glibc <sys/mount.h>   [Contents][Index]

14.82.3 fsopen

Documentation:
https://lore.kernel.org/all/159827190508.306468.12755090833140558156.stgit@warthog.procyon.org.uk/

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.35, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Glibc <sys/mount.h>   [Contents][Index]

14.82.4 fspick

Documentation:
https://lore.kernel.org/all/159827189767.306468.1803062787718957199.stgit@warthog.procyon.org.uk/

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.35, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Glibc <sys/mount.h>   [Contents][Index]

14.82.5 mount

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Glibc <sys/mount.h>   [Contents][Index]

14.82.6 mount_setattr

Documentation:
man mount_setattr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.35, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Glibc <sys/mount.h>   [Contents][Index]

14.82.7 move_mount

Documentation:
https://lore.kernel.org/all/159827189025.306468.4916341547843731338.stgit@warthog.procyon.org.uk/

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.35, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Glibc <sys/mount.h>   [Contents][Index]

14.82.8 open_tree

Documentation:
https://lore.kernel.org/all/159827188271.306468.16962617119460123110.stgit@warthog.procyon.org.uk/

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.35, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Glibc <sys/mount.h>   [Contents][Index]

14.82.9 umount

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, AIX 5.1, mingw, MSVC 14.

Previous: , Up: Glibc <sys/mount.h>   [Contents][Index]

14.82.10 umount2

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11.23, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.83 Glibc <sys/personality.h>

Up: Glibc <sys/personality.h>   [Contents][Index]

14.83.1 personality

Documentation:
man personality

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 4.0.2.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.84 Glibc <sys/pidfd.h>

Next: , Up: Glibc <sys/pidfd.h>   [Contents][Index]

14.84.1 pidfd_getfd

Documentation:
man pidfd_getfd

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.35, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Glibc <sys/pidfd.h>   [Contents][Index]

14.84.2 pidfd_getpid

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.38, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Glibc <sys/pidfd.h>   [Contents][Index]

14.84.3 pidfd_open

Documentation:
man pidfd_open

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.35, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Previous: , Up: Glibc <sys/pidfd.h>   [Contents][Index]

14.84.4 pidfd_send_signal

Documentation:
man pidfd_send_signal

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.35, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.5.3, mingw, MSVC 14, Android.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.85 Glibc <sys/prctl.h>

Up: Glibc <sys/prctl.h>   [Contents][Index]

14.85.1 prctl

Documentation:
man prctl

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.86 Glibc <sys/profil.h>

Up: Glibc <sys/profil.h>   [Contents][Index]

14.86.1 sprofil

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11.11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.87 Glibc <sys/ptrace.h>

Up: Glibc <sys/ptrace.h>   [Contents][Index]

14.87.1 ptrace

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-ptrace-1.html

Documentation:
man ptrace

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.88 Glibc <sys/quota.h>

Up: Glibc <sys/quota.h>   [Contents][Index]

14.88.1 quotactl

Documentation:
man quotactl

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.89 Glibc <sys/random.h>

Up: Glibc <sys/random.h>   [Contents][Index]

14.89.1 getrandom

Documentation:

Gnulib module: getrandom

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.24, macOS 14, FreeBSD 11.0, NetBSD 9.3, OpenBSD 7.9, Minix 3.3, AIX 7.1, HP-UX 11.31, Solaris 11.0, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.
  • This function has a different return type on some platforms: Solaris 11.4.

Portability problems not fixed by Gnulib:

  • The GRND_INSECURE flag is missing on some platforms: glibc 2.34, macOS 10.15, GNU/kFreeBSD, FreeBSD 12.0, OpenBSD 7.9, Minix 3.3, Haiku.
  • The GRND_RANDOM flag has different effects on different platforms. Some platforms ignore the flag, or yield data that can fail to be random in some cases.

Although this function is intended to produce random data, the data’s security properties may not be appropriate for your application. For example, identical “random” data streams might be produced by rebooted virtual machines. If this is of concern you may need to use additional techniques such as hedging.2

Related modules include getentropy, which has a simpler but more-limited API, and crypto/gc-random, which is likely a better match for code already using the other crypto APIs.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.90 Glibc <sys/reboot.h>

Up: Glibc <sys/reboot.h>   [Contents][Index]

14.90.1 reboot

Documentation:
man reboot

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.91 Glibc Extensions to <sys/resource.h>

Up: Glibc Extensions to <sys/resource.h>   [Contents][Index]

14.91.1 prlimit

Documentation:
man prlimit

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.12, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 6.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.92 Glibc Extensions to <sys/sem.h>

Up: Glibc Extensions to <sys/sem.h>   [Contents][Index]

14.92.1 semtimedop

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11.11, Cygwin 2.9, mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.93 Glibc <sys/sendfile.h>

Up: Glibc <sys/sendfile.h>   [Contents][Index]

14.93.1 sendfile

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-sendfile.html

Documentation:
man sendfile

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Solaris 11 2010-11, Cygwin 2.9, mingw, MSVC 14, Android 4.4.
  • On platforms where off_t is a 32-bit type, this function may not work correctly on files larger than 2 GB. The fix is to use the AC_SYS_LARGEFILE macro.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.94 Glibc <sys/signalfd.h>

Up: Glibc <sys/signalfd.h>   [Contents][Index]

14.94.1 signalfd

Documentation:
man signalfd

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux, Cygwin, and illumos and is therefore missing on many non-glibc platforms: glibc 2.6, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.11.x, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.95 Glibc <sys/single_threaded.h>

Up: Glibc <sys/single_threaded.h>   [Contents][Index]

14.95.1 __libc_single_threaded

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Single_002dThreaded.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This variable is missing on all non-glibc platforms: glibc 2.31, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.96 Glibc Extensions to <sys/socket.h>

Next: , Up: Glibc Extensions to <sys/socket.h>   [Contents][Index]

14.96.1 isfdtype

Documentation:
man isfdtype

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <sys/socket.h>   [Contents][Index]

14.96.2 recvmmsg

Documentation:
man recvmmsg

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.11, macOS 14, FreeBSD 6.4, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 2.9, mingw, MSVC 14, Android 4.4.

Previous: , Up: Glibc Extensions to <sys/socket.h>   [Contents][Index]

14.96.3 sendmmsg

Documentation:
man sendmmsg

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.13, macOS 14, FreeBSD 6.4, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.3, Cygwin 2.9, mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.97 Glibc Extensions to <sys/stat.h>

Next: , Up: Glibc Extensions to <sys/stat.h>   [Contents][Index]

14.97.1 getumask

Documentation:

Gnulib module: getumask

Portability problems fixed by Gnulib:

  • This function exists only on Hurd and is therefore missing on all non-glibc platforms: glibc/Linux, glibc/kFreeBSD, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3, AIX 7.2, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <sys/stat.h>   [Contents][Index]

14.97.2 lchmod

Gnulib module: lchmod

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android API level 35.
  • This function is not declared on some platforms: HP-UX 11.31.
  • This function always fails with errno set to ENOSYS, even when the file is not a symbolic link: GNU/Linux with glibc 2.31.
  • This function does not fail when the file name argument ends in a slash and (without the slash) names a non-directory, on some platforms: AIX 7.2.

Portability problems not fixed by Gnulib:

  • Some platforms do not allow changing the access bits on symbolic links.
  • This function can fail with errno set to EMFILE or ENFILE, and it fails with errno set to EOPNOTSUPP if the /proc file system is not mounted: GNU/Linux with glibc 2.34.

Previous: , Up: Glibc Extensions to <sys/stat.h>   [Contents][Index]

14.97.3 statx

Documentation:
man statx

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.27, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android API level 29.
  • When AT_EMPTY_PATH is used, this function does not allow the file name to be a null pointer: glibc 2.40, Linux kernel 6.10.
  • There is an incompatible function of the same name on some platforms: AIX 5.2 or newer.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.98 Glibc <sys/statfs.h>

Next: , Up: Glibc <sys/statfs.h>   [Contents][Index]

14.98.1 fstatfs

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fstatfs-2.html

Documentation:
man fstatfs

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, mingw, MSVC 14.
  • On platforms where f_blocks in ‘struct statfs’ is a 32-bit value, this function may not work correctly on files systems larger than 4 TiB. The fix is to use the AC_SYS_LARGEFILE macro. This affects Mac OS X.

Previous: , Up: Glibc <sys/statfs.h>   [Contents][Index]

14.98.2 statfs

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-statfs-2.html

Documentation:
man statfs

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, mingw, MSVC 14.
  • On platforms where f_blocks in ‘struct statfs’ is a 32-bit value, this function may not work correctly on files systems larger than 4 TiB. The fix is to use the AC_SYS_LARGEFILE macro. This affects Mac OS X.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.99 Glibc <sys/swap.h>

Next: , Up: Glibc <sys/swap.h>   [Contents][Index]

14.99.1 swapoff

Documentation:
man swapoff

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 4.3.

Previous: , Up: Glibc <sys/swap.h>   [Contents][Index]

14.99.2 swapon

Documentation:
man swapon

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 4.3.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.100 Glibc <sys/sysctl.h>

Up: Glibc <sys/sysctl.h>   [Contents][Index]

14.100.1 sysctl

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.34, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.101 Glibc <sys/sysinfo.h>

Next: , Up: Glibc <sys/sysinfo.h>   [Contents][Index]

14.101.1 get_avphys_pages

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.1, mingw, MSVC 14, Android 5.1.

Next: , Previous: , Up: Glibc <sys/sysinfo.h>   [Contents][Index]

14.101.2 get_nprocs

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.7.1, mingw, MSVC 14, Android 5.1.

Gnulib provides the module nproc that performs a similar function but is portable to more systems.

Next: , Previous: , Up: Glibc <sys/sysinfo.h>   [Contents][Index]

14.101.3 get_nprocs_conf

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 10, Cygwin 1.7.1, mingw, MSVC 14, Android 5.1.

Next: , Previous: , Up: Glibc <sys/sysinfo.h>   [Contents][Index]

14.101.4 get_phys_pages

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.1, mingw, MSVC 14, Android 5.1.

Previous: , Up: Glibc <sys/sysinfo.h>   [Contents][Index]

14.101.5 sysinfo

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-sysinfo-1.html

Documentation:
man sysinfo

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Cygwin 1.7.9, mingw, MSVC 14.
  • This function is not declared and thus not part of the Android API for Android API levels < 9.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.102 Glibc <sys/syslog.h>

Up: Glibc <sys/syslog.h>   [Contents][Index]

14.102.1 vsyslog

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-vsyslog-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.103 Glibc <sys/sysmacros.h>

Next: , Up: Glibc <sys/sysmacros.h>   [Contents][Index]

14.103.1 gnu_dev_major

Documentation:
man gnu_dev_major

Gnulib module: —

Portability problems fixed by Gnulib:

  • The AC_HEADER_MAJOR macro in Autoconf 2.69 and earlier fails to set MAJOR_IN_SYSMACROS when it detects namespace pollution in sys/types.h; which in turn provokes deprecation warnings in glibc 2.25.

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <sys/sysmacros.h>   [Contents][Index]

14.103.2 gnu_dev_makedev

Documentation:
man gnu_dev_makedev

Gnulib module: —

Portability problems fixed by Gnulib:

  • The AC_HEADER_MAJOR macro in Autoconf 2.69 and earlier fails to set MAJOR_IN_SYSMACROS when it detects namespace pollution in sys/types.h; which in turn provokes deprecation warnings in glibc 2.25.

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <sys/sysmacros.h>   [Contents][Index]

14.103.3 gnu_dev_minor

Documentation:
man gnu_dev_minor

Gnulib module: —

Portability problems fixed by Gnulib:

  • The AC_HEADER_MAJOR macro in Autoconf 2.69 and earlier fails to set MAJOR_IN_SYSMACROS when it detects namespace pollution in sys/types.h; which in turn provokes deprecation warnings in glibc 2.25.

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.104 Glibc Extensions to <sys/time.h>

Next: , Up: Glibc Extensions to <sys/time.h>   [Contents][Index]

14.104.1 adjtime

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-adjtime-2.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <sys/time.h>   [Contents][Index]

14.104.2 futimes

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-futimes.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 7.1.
  • This function cannot set full timestamp resolution. Use futimens(fd,times) instead.

Next: , Previous: , Up: Glibc Extensions to <sys/time.h>   [Contents][Index]

14.104.3 futimesat

Documentation:
man futimesat

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.3.6, macOS 14, FreeBSD 6.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.5.x, mingw, MSVC 14, Android 7.1.
  • On some platforms, this function mis-handles a trailing slash: Solaris 9.
  • This function cannot set full timestamp resolution. Use 
    file ? utimensat(fd, file, times, 0)
     : futimens(fd, times)

    or the gnulib module fdutimensat, instead.

Next: , Previous: , Up: Glibc Extensions to <sys/time.h>   [Contents][Index]

14.104.4 lutimes

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 7.1.
  • This function cannot set full timestamp resolution. Use utimensat(AT_FDCWD,file,times,AT_SYMLINK_NOFOLLOW), or the gnulib module utimens, instead.
  • The mere act of using lstat modifies the access time of symlinks on some platforms, so lutimes can only effectively change modification time: Cygwin.

Previous: , Up: Glibc Extensions to <sys/time.h>   [Contents][Index]

14.104.5 settimeofday

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.105 Glibc <sys/timerfd.h>

Next: , Up: Glibc <sys/timerfd.h>   [Contents][Index]

14.105.1 timerfd_create

Documentation:
man timerfd_create

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux, FreeBSD, NetBSD, Cygwin, and illumos and is therefore missing on many non-glibc platforms: glibc 2.7, macOS 14, FreeBSD 13.2, NetBSD 9.3, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.11.x, mingw, MSVC 14, Android 4.3.

Next: , Previous: , Up: Glibc <sys/timerfd.h>   [Contents][Index]

14.105.2 timerfd_gettime

Documentation:
man timerfd_gettime

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux, FreeBSD, NetBSD, Cygwin, and illumos and is therefore missing on many non-glibc platforms: glibc 2.7, macOS 14, FreeBSD 13.2, NetBSD 9.3, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.11.x, mingw, MSVC 14, Android 4.3.

Previous: , Up: Glibc <sys/timerfd.h>   [Contents][Index]

14.105.3 timerfd_settime

Documentation:
man timerfd_settime

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux, FreeBSD, NetBSD, Cygwin, and illumos and is therefore missing on many non-glibc platforms: glibc 2.7, macOS 14, FreeBSD 13.2, NetBSD 9.3, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.11.x, mingw, MSVC 14, Android 4.3.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.106 Glibc <sys/timex.h>

Next: , Up: Glibc <sys/timex.h>   [Contents][Index]

14.106.1 adjtimex

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 6.0.

Next: , Previous: , Up: Glibc <sys/timex.h>   [Contents][Index]

14.106.2 ntp_adjtime

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.5, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <sys/timex.h>   [Contents][Index]

14.106.3 ntp_gettime

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Mac OS X 10.5, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <sys/timex.h>   [Contents][Index]

14.106.4 ntp_gettimex

Documentation:
man ntp_gettimex

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.11, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.107 Glibc Extensions to <sys/uio.h>

Next: , Up: Glibc Extensions to <sys/uio.h>   [Contents][Index]

14.107.1 preadv

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.9, macOS 10.15, FreeBSD 5.2.1, Minix 3.1.8, AIX 5.2, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 6.0.
  • On platforms where off_t is a 32-bit type, this function may not work correctly on files larger than 2 GB. The fix is to use the AC_SYS_LARGEFILE macro.

Next: , Previous: , Up: Glibc Extensions to <sys/uio.h>   [Contents][Index]

14.107.2 preadv2

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many platforms: glibc 2.25, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android API level 32.

Next: , Previous: , Up: Glibc Extensions to <sys/uio.h>   [Contents][Index]

14.107.3 process_vm_readv

Documentation:
man process_vm_readv

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.14, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 5.1.

Next: , Previous: , Up: Glibc Extensions to <sys/uio.h>   [Contents][Index]

14.107.4 process_vm_writev

Documentation:
man process_vm_writev

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.14, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 5.1.

Next: , Previous: , Up: Glibc Extensions to <sys/uio.h>   [Contents][Index]

14.107.5 pwritev

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.9, macOS 10.15, FreeBSD 5.2.1, Minix 3.1.8, AIX 5.2, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 6.0.
  • On platforms where off_t is a 32-bit type, this function may not work correctly on files larger than 2 GB. The fix is to use the AC_SYS_LARGEFILE macro.

Previous: , Up: Glibc Extensions to <sys/uio.h>   [Contents][Index]

14.107.6 pwritev2

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many platforms: glibc 2.25, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android API level 32.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.108 Glibc <sys/ustat.h>

Up: Glibc <sys/ustat.h>   [Contents][Index]

14.108.1 ustat

Documentation:
man ustat

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.109 Glibc <sys/vlimit.h>

Up: Glibc <sys/vlimit.h>   [Contents][Index]

14.109.1 vlimit

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.110 Glibc Extensions to <sys/wait.h>

Next: , Up: Glibc Extensions to <sys/wait.h>   [Contents][Index]

14.110.1 wait3

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 9.0.
  • This function is not declared on some platforms: Android 13.

Previous: , Up: Glibc Extensions to <sys/wait.h>   [Contents][Index]

14.110.2 wait4

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-wait4-2.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11.11, mingw, MSVC 14, Android 4.2.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.111 Glibc <sys/xattr.h>

Next: , Up: Glibc <sys/xattr.h>   [Contents][Index]

14.111.1 fgetxattr

Documentation:
man fgetxattr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: FreeBSD 14.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android 4.0.4.
  • This function has extra offset and options parameters on some platforms: macOS 14.

Next: , Previous: , Up: Glibc <sys/xattr.h>   [Contents][Index]

14.111.2 flistxattr

Documentation:
man flistxattr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: FreeBSD 14.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android 4.0.4.
  • This function has an extra options parameter on some platforms: macOS 14.
  • This function fails with EACCES on unreadable files accessed via NFS: Linux kernel 6.12.
  • This function does not report synthetic security.* extended attributes on tmpfs and kernfs-based file systems: Linux kernel 6.14.
  • This function can fail with ERANGE even if the buffer is large enough: Linux kernel 6.15.

Next: , Previous: , Up: Glibc <sys/xattr.h>   [Contents][Index]

14.111.3 fremovexattr

Documentation:
man fremovexattr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: FreeBSD 14.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android 4.0.4.
  • This function has an extra options parameter on some platforms: macOS 14.

Next: , Previous: , Up: Glibc <sys/xattr.h>   [Contents][Index]

14.111.4 fsetxattr

Documentation:
man fsetxattr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: FreeBSD 14.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android 4.0.4.
  • This function has extra offset and options parameters and no flags parameter on some platforms: macOS 14.

Next: , Previous: , Up: Glibc <sys/xattr.h>   [Contents][Index]

14.111.5 getxattr

Documentation:
man getxattr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: FreeBSD 14.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android 4.0.4.
  • This function has extra offset and options parameters on some platforms: macOS 14.

Next: , Previous: , Up: Glibc <sys/xattr.h>   [Contents][Index]

14.111.6 lgetxattr

Documentation:
man lgetxattr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android 4.0.4.

Next: , Previous: , Up: Glibc <sys/xattr.h>   [Contents][Index]

14.111.7 listxattr

Documentation:
man listxattr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: FreeBSD 14.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android 4.0.4.
  • This function has an extra options parameter on some platforms: macOS 14.
  • This function fails with EACCES on unreadable files accessed via NFS: Linux kernel 6.12.
  • This function does not report synthetic security.* extended attributes on tmpfs and kernfs-based file systems: Linux kernel 6.14.
  • This function can fail with ERANGE even if the buffer is large enough: Linux kernel 6.15.

Next: , Previous: , Up: Glibc <sys/xattr.h>   [Contents][Index]

14.111.8 llistxattr

Documentation:
man llistxattr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android 4.0.4.
  • This function fails with EACCES on unreadable files accessed via NFS: Linux kernel 6.12.
  • This function does not report synthetic security.* extended attributes on tmpfs and kernfs-based file systems: Linux kernel 6.14.
  • This function can fail with ERANGE even if the buffer is large enough: Linux kernel 6.15.

Next: , Previous: , Up: Glibc <sys/xattr.h>   [Contents][Index]

14.111.9 lremovexattr

Documentation:
man lremovexattr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android 4.0.4.

Next: , Previous: , Up: Glibc <sys/xattr.h>   [Contents][Index]

14.111.10 lsetxattr

Documentation:
man lsetxattr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android 4.0.4.

Next: , Previous: , Up: Glibc <sys/xattr.h>   [Contents][Index]

14.111.11 removexattr

Documentation:
man removexattr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: FreeBSD 14.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android 4.0.4.
  • This function has an extra options parameter on some platforms: macOS 14.

Previous: , Up: Glibc <sys/xattr.h>   [Contents][Index]

14.111.12 setxattr

Documentation:
man setxattr

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: FreeBSD 14.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android 4.0.4.
  • This function has extra offset and options parameters and no flags parameter on some platforms: macOS 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.112 Glibc Extensions to <termios.h>

Next: , Up: Glibc Extensions to <termios.h>   [Contents][Index]

14.112.1 cfmakeraw

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-cfmakeraw-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 1.5.x, mingw, MSVC 14, Android 4.4.

Previous: , Up: Glibc Extensions to <termios.h>   [Contents][Index]

14.112.2 cfsetspeed

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-cfsetspeed-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.113 Glibc Extensions to <time.h>

Next: , Up: Glibc Extensions to <time.h>   [Contents][Index]

14.113.1 clock_adjtime

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on many non-glibc platforms: glibc 2.13, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 6.0.

Next: , Previous: , Up: Glibc Extensions to <time.h>   [Contents][Index]

14.113.2 dysize

Documentation:
man dysize

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <time.h>   [Contents][Index]

14.113.3 getdate_r

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <time.h>   [Contents][Index]

14.113.4 stime

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-stime-2.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <time.h>   [Contents][Index]

14.113.5 strptime_l

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.

Previous: , Up: Glibc Extensions to <time.h>   [Contents][Index]

14.113.6 timelocal

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, HP-UX 11, Solaris 11.3, mingw, MSVC 14, Android 3.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.114 Glibc <ttyent.h>

Next: , Up: Glibc <ttyent.h>   [Contents][Index]

14.114.1 endttyent

Documentation:
man endttyent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <ttyent.h>   [Contents][Index]

14.114.2 getttyent

Documentation:
man getttyent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <ttyent.h>   [Contents][Index]

14.114.3 getttynam

Documentation:
man getttynam

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <ttyent.h>   [Contents][Index]

14.114.4 setttyent

Documentation:
man setttyent

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.115 Glibc Extensions to <unistd.h>

Next: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.1 acct

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-acct-3.html

Documentation:
man acct

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.2 brk

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 12.2/arm64, AIX 5.1, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.3 chroot

Documentation:
man chroot

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: AIX 5.1, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.4 closefrom

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Opening-and-Closing-Files.html

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.33, macOS 14, FreeBSD 7.2, Minix 3.3.0, AIX 7.1, HP-UX 11.31, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Note (quoted from man close): “The [POSIX] standard developers rejected a proposal to add closefrom() to the [POSIX] standard. Because the standard permits implementations to use inherited file descriptors as a means of providing a conforming environment for the child process, it is not possible to standardize an interface that closes arbitrary file descriptors above a certain value while still guaranteeing a conforming environment.”

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.5 close_range

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: glibc 2.33, macOS 14, FreeBSD 12.4, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.3.1, HP-UX 11.31, Solaris 11.4, Cygwin 3.4.x, mingw, MSVC 14, Android API level 33.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.6 copy_file_range

Documentation:

Gnulib module: copy-file-range

Portability problems fixed by Gnulib:

  • This function exists only on Linux and FreeBSD and is therefore missing on many platforms: glibc 2.26, macOS 14, FreeBSD 12.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android API level 33. But the replacement function is only a stub: It always fails with error ENOSYS.
  • This function has many problems on Linux kernel versions before 5.3. See “Fixes for major copy_file_range() issues”. On these kernel versions, the replacement function always fails with error ENOSYS.
  • This function returns an incorrect value when the number of bytes copied exceeds INT_MAX on systems using glibc version 2.41 or 2.42. See glibc bug 33245.
  • This function is provided on GNU/Hurd but it is only a stub: It always fails with error ENOSYS.

Portability problems not fixed by Gnulib:

  • If built with include files for Linux kernel 5.3 or later, the Gnulib substitute may misbehave when run on Linux kernel 5.2 or earlier. A similar problem exists if built with include files for glibc 2.43 or later, and run on glibc 2.41 or 2.42.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.7 daemon

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-daemon-3.html

Documentation:
man daemon

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.8 eaccess

Documentation:
man eaccess

This function is an alias of euidaccess. See euidaccess.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.9 endusershell

Documentation:
man endusershell

Gnulib module: getusershell

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 9.0.
  • This function is missing a declaration on some platforms: Solaris 9.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.10 euidaccess

Documentation:
man euidaccess

Gnulib module: euidaccess

Portability problems fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Other problems of this function:

  • There is an inherent race between calling this function and performing some action based on the results; you should think twice before trusting this function, especially in a set-uid or set-gid program.
  • This function does not have an option for not following symbolic links (like stat versus lstat). If you need this option, use the Gnulib module faccessat with the AT_EACCESS flag.
  • On Solaris, for the root user, any file is X_OK even if the file does not have the x permission bit set.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.11 execveat

Documentation: man execveat.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: glibc 2.33/Linux, glibc 2.34/Hurd, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.3.0, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.12 execvpe

Documentation:
man execvpe

Gnulib module: execvpe

Portability problems fixed by Gnulib:

  • This function is missing on many non-glibc platforms: glibc 2.10, macOS 14, FreeBSD 14.0, NetBSD 7.1, OpenBSD 3.8, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Cygwin 1.5.x, mingw, Android 4.4.
  • This function is not declared on some platforms: AIX 7.1.
  • On Windows platforms (excluding Cygwin), this function does not pass command-line arguments correctly if they contain space, tab, backslash, or double-quote characters.
  • On Windows platforms (excluding Cygwin), this function spawns an asynchronous child process and then exits the current process immediately. As a consequence, the parent of the current process 1. may incorrectly proceed as if its child had exited, and 2. will never see the child’s exit status.
  • On Windows platforms (excluding Cygwin), the return type of this function is intptr_t, not int.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.13 get_current_dir_name

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 1.7.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.14 getdomainname

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getdomainname.html

Documentation:

Gnulib module: getdomainname

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Solaris 11.3, mingw, MSVC 14, Android 7.1.
  • This function is declared in netdb.h, not in unistd.h, on some platforms: AIX 7.1.
  • The second argument is of type int, not size_t, on some platforms: macOS 14, FreeBSD 14.0, AIX 7.1.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.15 getdtablesize

SUSv2 specification: https://pubs.opengroup.org/onlinepubs/7908799/xsh/getdtablesize.html

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getdtablesize.html

Documentation:
man getdtablesize

Gnulib module: getdtablesize

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Android LP64, mingw, MSVC 14, Android 9.0.
  • This function is not declared on some platforms: Android 13 (LP32?).
  • This function does not represent the true RLIMIT_NOFILE soft limit on some platforms: Android 13 (LP32?), Cygwin 1.7.25.

Portability problems not fixed by Gnulib:

  • On OpenVMS, this function returns the maximum number of open file descriptors in a process. The possible values of file descriptors are not constrained by this function.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.16 getpagesize

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getpagesize.html

Documentation:

Gnulib module: getpagesize

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: MSVC 14, Android 4.4.
  • This function is not declared on some platforms: HP-UX 11 with compiler option -D_XOPEN_SOURCE=600.
  • This function is broken on some platforms: mingw.

Portability problems not fixed by Gnulib:

  • The function has never been in POSIX and was removed from the Single UNIX Specification in SUSv3 (2001). Although portable programs are supposed to use sysconf (_SC_PAGESIZE) instead, in practice getpagesize can be a little faster.
  • On typical platforms this function’s API limits page sizes to at most 1 GiB, even though sysconf (_SC_PAGESIZE) does not have this limitation. However, this has not been a practical problem yet, and so many programs use getpagesize that it’s unlikely that new platforms would introduce larger page sizes any time soon.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.17 getpass

Documentation:

Gnulib module: getpass or getpass-gnu

Portability problems fixed by either Gnulib module getpass or getpass-gnu:

  • This function is missing on some platforms: mingw, MSVC 14, Android 9.0.
  • This function cannot be called from plain inline or extern inline functions on some platforms: Android 13.

Portability problems fixed by Gnulib module getpass-gnu:

  • The returned password is truncated to PASS_MAX characters on some platforms: uClibc (256), musl (128), macOS 14 (128), FreeBSD 14.0 (128), NetBSD 3.0 (128), OpenBSD 4.0 (128), AIX 5.1 (32), HP-UX 11 (8), Solaris 11 2010-11 (8, even less than PASS_MAX), Cygwin (128). The gnulib implementation returns the password untruncated.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.18 gettid

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function exists only on Linux and is therefore missing on most non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.19 getusershell

Documentation:
man getusershell

Gnulib module: getusershell

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 9.0.
  • This function is missing a declaration on some platforms: Solaris 9.
  • This function mistakenly returns comments and empty lines on some platforms: musl libc 1.2.4

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.20 group_member

Documentation:
man group_member

Gnulib module: group-member

Portability problems fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.21 profil

Documentation:
man profil

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.22 revoke

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.23 sbrk

Documentation:
man sbrk

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 12.2/arm64, AIX 5.1, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.24 setlogin

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.25 setdomainname

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Cygwin 2.9, mingw, MSVC 14, Android 7.1.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.26 sethostid

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.27 sethostname

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-sethostname-2.html

Documentation:

Gnulib module: sethostname

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, Cygwin 1.7.x, mingw, MSVC 14, Android 5.1. Note that the Gnulib replacement may fail with ENOSYS on some platforms.
  • This function is not declared on some platforms: AIX 7.1, Solaris 10.

Portability problems not fixed by Gnulib:

  • The first parameter is char * instead of const char * on some platforms: Solaris 11 2010-11.
  • The second parameter is int instead of size_t on some platforms: macOS 14, FreeBSD 14.0, MidnightBSD 3.0, Solaris 11 2010-11, Solaris 11 OpenIndiana, Solaris 11 OmniOS.
  • This function does not reject a too long host name on some platforms: Cygwin 3.5.3, Haiku.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.28 setusershell

Documentation:
man setusershell

Gnulib module: getusershell

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14, Android 9.0.
  • This function is missing a declaration on some platforms: Solaris 9.

Portability problems not fixed by Gnulib:

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.29 syncfs

Documentation:
man syncfs

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: glibc 2.13, macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 8.1.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.30 syscall

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, Cygwin 2.9, mingw, MSVC 14.

Next: , Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.31 ttyslot

Documentation:
man ttyslot

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc Extensions to <unistd.h>   [Contents][Index]

14.115.32 vhangup

Documentation:
man vhangup

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.116 Glibc <utmp.h>

Next: , Up: Glibc <utmp.h>   [Contents][Index]

14.116.1 endutent

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-endutent-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14.
  • This function is not declared on some platforms: Android before ca. 2015.

Next: , Previous: , Up: Glibc <utmp.h>   [Contents][Index]

14.116.2 getutent

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getutent-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <utmp.h>   [Contents][Index]

14.116.3 getutent_r

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getutent-r-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <utmp.h>   [Contents][Index]

14.116.4 getutid

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <utmp.h>   [Contents][Index]

14.116.5 getutid_r

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <utmp.h>   [Contents][Index]

14.116.6 getutline

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <utmp.h>   [Contents][Index]

14.116.7 getutline_r

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <utmp.h>   [Contents][Index]

14.116.8 pututline

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <utmp.h>   [Contents][Index]

14.116.9 setutent

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-setutent-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <utmp.h>   [Contents][Index]

14.116.10 updwtmp

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, HP-UX 11, mingw, MSVC 14, Android 9.0.

Next: , Previous: , Up: Glibc <utmp.h>   [Contents][Index]

14.116.11 utmpname

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-utmpname-3.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, mingw, MSVC 14.

Next: , Previous: , Up: Glibc <utmp.h>   [Contents][Index]

14.116.12 login

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: FreeBSD 14.0, NetBSD 5.0, OpenBSD 3.8, Minix 3.1.8, AIX 7.1, HP-UX 11.31, Solaris 11.4, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc <utmp.h>   [Contents][Index]

14.116.13 login_tty

Documentation:

Gnulib module: login_tty

Portability problems fixed by Gnulib:

  • This function is missing on some platforms: Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.3, Android 5.1.
  • This function is declared in <utmp.h> on glibc, Cygwin, Android, in <util.h> on macOS 14, NetBSD 5.0, OpenBSD 3.8, in <libutil.h> on FreeBSD 14.0, Haiku, and in <termios.h> on Solaris 11.4.
  • This function requires linking with -lutil on some platforms: glibc 2.3.6, FreeBSD 14.0, NetBSD 5.0, OpenBSD 3.8. It is available without link options on other platforms: macOS 14, Cygwin.

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: mingw, MSVC 14.

Next: , Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.117 Glibc Extensions to <utmpx.h>

Next: , Up: Glibc Extensions to <utmpx.h>   [Contents][Index]

14.117.1 getutmp

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • On some platforms, this function does not support timestamps past the year 2038: glibc 2.38 on 32-bit platforms like x86 and ARM where time_t was historically 32 bits.
  • On some platforms, this function misbehaves if the year2038 or year2038-recommended modules are used and the program is configured without the --disable-year2038 option. The readutmp module works around this problem: glibc 2.38 on 32-bit platforms like x86 and ARM where time_t was historically 32 bits. See Avoiding the year 2038 problem.

Next: , Previous: , Up: Glibc Extensions to <utmpx.h>   [Contents][Index]

14.117.2 getutmpx

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • On some platforms, this function does not support timestamps past the year 2038: glibc 2.38 on 32-bit platforms like x86 and ARM where time_t was historically 32 bits.
  • On some platforms, this function misbehaves if the year2038 or year2038-recommended modules are used and the program is configured without the --disable-year2038 option. The readutmp module works around this problem: glibc 2.38 on 32-bit platforms like x86 and ARM where time_t was historically 32 bits. See Avoiding the year 2038 problem.

Next: , Previous: , Up: Glibc Extensions to <utmpx.h>   [Contents][Index]

14.117.3 updwtmpx

Documentation:
man updwtmpx

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Cygwin 1.5.x, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc Extensions to <utmpx.h>   [Contents][Index]

14.117.4 utmpxname

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: FreeBSD 14.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, mingw, MSVC 14, Android 9.0.

Previous: , Up: Glibc Function Substitutes   [Contents][Index]

14.118 Glibc Extensions to <wchar.h>

Next: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.1 fgetwc_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fgetwc-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.2 fgetws_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fgetws-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.3 fputwc_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fputwc-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.4 fputws_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-fputws-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.5 getwc_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getwc-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.6 getwchar_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-getwchar-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on all non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.7 putwc_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-putwc-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on some platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.8 putwchar_unlocked

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-putwchar-unlocked-1.html

Documentation:

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 9.0.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.9 wcschrnul

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Search-Functions.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.10 wcsftime_l

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.11 wcstod_l

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 7.1, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.12 wcstof_l

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 7.1, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.13 wcstol_l

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.14 wcstold_l

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 7.1, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.15 wcstoll_l

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.16 wcstoq

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-wcstoq.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Parsing-of-Integers.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.17 wcstoul_l

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 8.1.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.18 wcstoull_l

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many platforms: FreeBSD 6.0, NetBSD 5.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 1.7.x, mingw, MSVC 14, Android 4.4.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.19 wcstouq

LSB specification:
https://refspecs.linuxbase.org/LSB_5.0.0/LSB-Core-generic/LSB-Core-generic/baselib-wcstouq.html

Documentation:
https://www.gnu.org/software/libc/manual/html_node/Parsing-of-Integers.html.

Gnulib module: —

Portability problems fixed by Gnulib:

Portability problems not fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 14.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9, mingw, MSVC 14, Android 9.0.
  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Previous: , Up: Glibc Extensions to <wchar.h>   [Contents][Index]

14.118.20 wmempcpy

Documentation:

Gnulib module: wmempcpy

Portability problems fixed by Gnulib:

  • This function is missing on many non-glibc platforms: macOS 14, FreeBSD 13.0, NetBSD 10.0, OpenBSD 7.9, Minix 3.1.8, AIX 5.1, HP-UX 11, Solaris 11.4, Cygwin 2.9.x, mingw, MSVC 14, Android 5.1.

Portability problems not fixed by Gnulib:

  • On Windows and 32-bit AIX platforms, wchar_t is a 16-bit type and therefore cannot accommodate all Unicode characters.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

15 Native Windows Support

There are three ways to create binaries that run on Microsoft Windows:

This chapter deals with the MinGW and MSVC platforms, commonly called “native Windows” platforms. Cygwin, on the other hand, is close enough to POSIX that it can be treated like any other Unix-like platform.

Next: , Up: Native Windows Support   [Contents][Index]

15.1 Libtool and Windows

If you want it to be possible to compile your program for a native Windows platform and you use Libtool, you need to use the win32-dll option of LT_INIT. In other words, put: 

LT_INIT([win32-dll])

in your configure.ac. This sets the correct names for the OBJDUMP, DLLTOOL, and AS tools for the build.

If you are building a library, you will also need to pass -no-undefined to make sure Libtool produces a DLL for your library. From a Makefile.am: 

libgsasl_la_LDFLAGS += -no-undefined

Next: , Previous: , Up: Native Windows Support   [Contents][Index]

15.2 Large File Support

This module provides support for files 2 GiB and larger, or with device or inode numbers exceeding 32 bits. To this effect, it attempts to ensure that types like off_t and ino_t are 64-bit, at least on the following platforms: glibc, Mac OS X, FreeBSD, NetBSD, OpenBSD, AIX, HP-UX, Solaris, Cygwin, mingw, MSVC.

If the types cannot be made 64-bit, configure issues a warning and proceeds.

This module gives configure an option ‘--disable-largefile’ that suppresses support for large files. This may be useful if the package links to other libraries whose user-facing ABIs still require off_t or most other file-related types to be 32-bit on your platform.

This module also adds to configure an option --enable-year2038, needed on some platforms to access files with timestamps past the year 2038. See Avoiding the year 2038 problem.

Next: , Previous: , Up: Native Windows Support   [Contents][Index]

15.3 Inode numbers on Windows

The module ‘windows-stat-inodes’ ensures that, on native Windows platforms, struct stat contains st_dev, st_ino fields that are able to distinguish different inodes.

Note: Such values can only be provided for most files on the file system. For a few files (such as inaccessible files), st_dev and st_ino are set to 0. Therefore, you should test whether st_dev != 0 && st_ino != 0, before going to make inferences based on the file identity based on st_dev and st_ino.

Next: , Previous: , Up: Native Windows Support   [Contents][Index]

15.4 Precise file timestamps on Windows

The module ‘windows-stat-timespec’ ensures that, on native Windows platforms, struct stat contains st_atim, st_mtim, st_ctim fields of type struct timespec, providing 100 ns resolution for the timestamps of files.

Note: On some types of file systems, the timestamp resolution is limited by the file system. For example, on FAT file systems, st_mtim only has a resolution of 2 seconds. For more details, see https://docs.microsoft.com/en-us/windows/desktop/SysInfo/file-times.

Next: , Previous: , Up: Native Windows Support   [Contents][Index]

15.5 Avoiding the year 2038 problem

The year 2038 problem denotes unpredictable behaviour that will likely occur in the year 2038, for programs that use a 32-bit signed integer ‘time_t’ type that cannot represent timestamps on or after 2038-01-19 03:14:08 UTC. See Year 2038 problem for details.

The Gnulib module ‘year2038’ fixes this problem on some platforms, by making time_t wide enough to represent timestamps after 2038. This has no effect on most current platforms, which have timestamps that are already wide enough. However, ‘year2038’ by default arranges for builds on legacy 32-bit Linux kernels running glibc 2.34 and later to compile with ‘_TIME_BITS=64’ to get wider timestamps. On older platforms that do not support timestamps after the year 2038, ‘year2038’ causes configure to issue a warning but still proceed. On platforms that appear to support post-2038 timestamps but where something prevents this from working, configure fails.

The default behavior of ‘year2038’ can be overridden by using the configure option --disable-year2038, which suppresses support for post-2038 timestamps. This may be useful if the package links to other libraries whose user-facing ABIs still require time_t to be 32-bit on your platform.

The Gnulib module ‘year2038-recommended’ is like ‘year2038’, except it by default rejects platforms where time_t cannot represent timestamps after 2038. If this module is used and a 32-platform cannot support 64-bit time_t, one can still fix the year-2038 problem by using a 64-bit instead of a 32-bit build, as noted in the architecture list below. If all else fails one can configure with --disable-year2038; however, the resulting programs will mishandle timestamps after 2038.

The Gnulib module ‘year2038-recommended’ is designed for packages intended for use on 32-bit platforms after the year 2038. If your package is commonly built on 32-bit platforms that will not be used after the year 2038, you can use the ‘year2038’ module instead, to save builders the trouble of configuring with --disable-year2038.

If the Gnulib module ‘largefile’ is used but neither ‘year2038’ nor ‘year2038-recommended’ is used, configure will have an option --enable-year2038 that causes configure to behave as if ‘year2038’ was used. This is for packages that have long used ‘largefile’ but have not gotten around to upgrading their Gnulib module list to include ‘year2038’ or ‘year2038-recommended’. See Large File Support.

With the ‘year2038-recommended’ module, configure by default should work on the following 32-bit platforms (or 32-bit ABIs in bi-arch systems):

  • Linux kernel 5.1 (2019) and later with glibc 2.34 (2021) and later on x86, arm, mips (o32 or n32 ABI), powerpc32, sparc32, s390, hppa, m68k, sh, csky, microblaze, nios2,
  • Linux kernel 5.1 (2019) and later with musl libc 1.2 (2020) and later on x86,
  • Linux on arc, loong32, or1k, riscv32 and x86_64-x32,
  • NetBSD 6.0 (2012) and later on x86 and sparc,
  • OpenBSD 5.5 (2014) and later on x86,
  • FreeBSD/arm,
  • Minix 3.3 (2014).

Whereas with ‘year2038-recommended’, configure should by default fail on earlier versions of the abovementioned platforms if a version is listed, and it should also by default fail on all versions of the following older 32-bit platforms or ABIs:

  • Android on ARMv7 or x86,
  • Mac OS X 10.6 (2009) and earlier on x86 and powerpc,
  • GNU/Hurd/x86,
  • GNU/kFreeBSD/x86,
  • FreeBSD/x86 (this port demoted to Tier 2 in FreeBSD 13 [2021] and planned to never have 64-bit time_t),
  • MidnightBSD/x86,
  • AIX/powerpc (to fix, configure with ‘CC='gcc -maix64' AR='ar -X64'’),
  • Solaris 11.4 (2018) and earlier on x86 and sparc (to fix, configure with ‘CC='gcc -m64'’),
  • Cygwin 3.3.6 (2022) and earlier on x86,
  • Haiku/x86.

If you use the ‘year2038’ or ‘year2038-recommended’ modules, and configure to support timestamps after the year 2038, your code should not include ‘<utmp.h>’ or ‘<utmpx.h>’ directly, because these include files do not work with 64-bit timestamps if the platform’s time_t was traditionally 32 bits. Your code can instead use the ‘readutmp’ module, which works around this problem.

Next: , Previous: , Up: Native Windows Support   [Contents][Index]

15.6 Windows sockets

One of the portability problems for native Windows are sockets and networking functions.

15.6.1 Getaddrinfo and WINVER

This was written for the getaddrinfo module, but may be applicable to other functions too.

The getaddrinfo function exists in ws2tcpip.h and -lws2_32 on Windows XP. The function declaration is present if WINVER >= 0x0501. Windows 2000 does not have getaddrinfo in its WS2_32.DLL.

Thus, if you want to assume Windows XP or later, you can add AC_DEFINE([WINVER], [0x0501]) to avoid compiling the (partial) getaddrinfo implementation.

If you want to support Windows 2000, don’t do anything. The replacement function will open WS2_32.DLL during run-time to see if there is a getaddrinfo function available, and use it when available.

Next: , Previous: , Up: Native Windows Support   [Contents][Index]

15.7 Native Windows Support without MSVC Support

If your package does not desire to have MSVC support, that is, if MinGW shall be the only native Windows platform that you wish to get support for from Gnulib, and you wish to minimize the number of files imported from Gnulib accordingly, you can do so by passing the options ‘--avoid=msvc-inval --avoid=msvc-nothrow’ to gnulib-tool.

Previous: , Up: Native Windows Support   [Contents][Index]

15.8 Visual Studio Compatibility

The lib-msvc-compat module detects whether the linker supports --output-def when building a library. That parameter is used to generate a DEF file for a shared library (DLL). DEF files are useful for developers that use Visual Studio to develop programs that links to your library. See the GNU LD manual for more information.

There are other ways to create a DEF file, but we believe they are all sub-optimal to using --output-def during the build process. The variants we have considered include:

  • Use DUMPBIN /EXPORTS. This is explained in https://docs.microsoft.com/en-us/cpp/build/reference/dash-exports. The tool does not generate DEF files directly, so its output needs to be post processed manually: 
    $ { echo EXPORTS; \
    dumpbin /EXPORTS libfoo-0.dll | tail -n+20 | awk '{ print $4 }'; \
  } > libfoo-0.def
$ lib /def:libfoo-0.def
  • Use IMPDEF. There is a tool called IMPDEF that can generate DEF files. However, it is not part of a standard Visual Studio installation. Further, it is documented as being an unreliable process.
  • Use DLLTOOL. The dlltool is part of the MinGW suite, and thus not part of a standard Visual Studio installation. The documentation for the IMPDEF tool claims that DLLTOOL is the wrong tool for this job. Finally, DLLTOOL does not generate DEF files directly, so it requires post-processing of the output.

If you are using libtool to build your shared library, here is how to use this module. Import lib-msvc-compat to your project, and then add the following lines to the Makefile.am that builds the library: 

if HAVE_LD_OUTPUT_DEF
libfoo_la_LDFLAGS += -Wl,--output-def,libfoo-$(DLL_VERSION).def
libfoo-$(DLL_VERSION).def: libfoo.la
defexecdir = $(libdir)
defexec_DATA = libfoo-$(DLL_VERSION).def
DISTCLEANFILES += $(defexec_DATA)
endif

The DLL_VERSION variable needs to be defined. It should be the shared library version number used in the DLL filename. For Windows targets you compute this value from the values you pass to Libtool’s -version-info. Assuming you have variables LT_CURRENT and LT_AGE defined for the CURRENT and AGE libtool version integers, you compute DLL_VERSION as follows: 

DLL_VERSION=`expr ${LT_CURRENT} - ${LT_AGE}`
AC_SUBST(DLL_VERSION)

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

16 Multithreading

Multithreading is a programming paradigm. In a multithreaded process, multiple threads execute concurrently (or quasi concurrently) at different places in the program, and a multithreaded program is one that contains primitives that can create threads. In contrast, a single-threaded process has just one thread, and a single-threaded program contains no multithreading primitives and so executes entirely in its process’s main thread.

There are three motivations for using multithreading in a program:

A multithreading API offers

Note: Programs that achieve multithreading through OpenMP (cf. the gnulib module ‘openmp’) don’t create and manage their threads themselves. Nevertheless, they need to use mutexes/locks in many cases.

Next: , Up: Multithreading   [Contents][Index]

16.1 The three multithreading APIs

Three multithreading APIs are available to Gnulib users:

  • POSIX multithreading,
  • ISO C multithreading,
  • Gnulib multithreading.

They are supported on all platforms that have multithreading in one form or the other. Currently, these are all platforms supported by Gnulib, except for Minix.

The main differences are:

  • The exit code of a thread is a pointer in the POSIX and Gnulib APIs, but only an int in the ISO C API.
  • The POSIX API has additional facilities for detaching threads, setting the priority of a thread, assigning a thread to a certain set of processors, and much more.
  • In the POSIX and ISO C APIs, most functions have a return code, and you are supposed to check the return code; even locking and unlocking a lock can fail. In the Gnulib API, many functions don’t have a return code; if they cannot complete, the program aborts. This sounds harsh, but such aborts have not been reported in 12 years.
  • In the ISO C API, the initialization of a statically allocated lock is clumsy: You have to initialize it through a once-only function.

Next: , Previous: , Up: Multithreading   [Contents][Index]

16.2 Choosing the right multithreading API

Here are guidelines for determining which multithreading API is best for your code.

In programs that use advanced POSIX APIs, such as detached threads (pthread_detach), signal blocking (pthread_sigmask), priorities (pthread_setschedparam), processor affinity (pthread_setaffinity_np), it is best to use the POSIX API. This is because you cannot convert an ISO C thrd_t or a Gnulib gl_thread_t to a POSIX pthread_t.

In code that is shared with glibc, it is best to use the POSIX API as well.

In libraries, it is best to use the Gnulib API. This is because it gives the person who builds the library an option ‘--enable-threads={isoc,posix,windows}’, that determines on which native multithreading API of the platform to rely. In other words, with this choice, you can minimize the amount of glue code that your library needs to contain.

In the other cases, the POSIX API and the Gnulib API are equally well suited.

The ISO C API is never the best choice, as of this writing (2020).

Next: , Previous: , Up: Multithreading   [Contents][Index]

16.3 The POSIX multithreading API

The POSIX multithreading API is documented in POSIX https://pubs.opengroup.org/onlinepubs/9799919799/.

To make use of POSIX multithreading, even on platforms that don’t support it natively (most prominently, native Windows), use the following Gnulib modules:

PurposeModule
For thread creation and management: pthread-thread
For simple and recursive locks: pthread-mutex
For read-write locks: pthread-rwlock
For once-only execution: pthread-once
For “condition variables” (wait queues): pthread-cond
For thread-local storage: pthread-tss
For relinquishing control: sched_yield
For spin locks: pthread-spin

There is also a convenience module named pthread which depends on all of these (except sched_yield); so you don’t need to enumerate these modules one by one.

Next: , Previous: , Up: Multithreading   [Contents][Index]

16.4 The ISO C multithreading API

The ISO C multithreading API is documented in ISO C 11 https://www.open-std.org/jtc1/sc22/wg14/www/docs/n1570.pdf.

To make use of ISO C multithreading, even on platforms that don’t support it or have severe bugs, use the following Gnulib modules:

PurposeModule
For thread creation and management: thrd
For simple locks, recursive locks, and read-write locks: mtx
For once-only execution: mtx
For “condition variables” (wait queues): cnd
For thread-local storage: tss

There is also a convenience module named threads which depends on all of these; so you don’t need to enumerate these modules one by one.

Next: , Previous: , Up: Multithreading   [Contents][Index]

16.5 The Gnulib multithreading API

The Gnulib multithreading API is documented in the respective include files:

  • <glthread/thread.h>
  • <glthread/lock.h>
  • <glthread/once.h>
  • <glthread/cond.h>
  • <glthread/tls.h>
  • <glthread/yield.h>
  • <glthread/spin.h>

To make use of Gnulib multithreading, use the following Gnulib modules:

PurposeModule
For thread creation and management: thread
For simple locks, recursive locks, and read-write locks: lock
For once-only execution: once
For “condition variables” (wait queues): cond
For thread-local storage: tls
For relinquishing control: yield
For spin locks: spin

The Gnulib multithreading supports a configure option ‘--enable-threads={isoc,posix,windows}’, that chooses the underlying thread implementation. Currently (2020):

  • --enable-threads=posix is supported and is the best choice on all platforms except for native Windows. It may also work, to a limited extent, on mingw with the winpthreads library, but is not recommended there.
  • --enable-threads=windows is supported and is the best choice on native Windows platforms (mingw and MSVC). Except that on mingw, in C++ mode, use of the standard C++ library (<iostream> etc.) is incompatible with this choice.
  • --enable-threads=isoc is supported on all platforms that have the ISO C multithreading API. However, --enable-threads=posix is always a better choice.

Previous: , Up: Multithreading   [Contents][Index]

16.6 Optimizations of multithreaded code

Despite all the optimizations of multithreading primitives that have been implemented over the years – from atomic operations in hardware, over futexes and restartable sequences in the Linux kernel, to lock elision [1] [2]) – single-threaded programs can still profit performance-wise from the assertion that they are single-threaded.

Gnulib defines four facilities that help optimizing for the single-threaded case.

  • The Gnulib multithreading API, when used on glibc ≤ 2.32 and *BSD systems, uses weak symbols to detect whether the program is linked with libpthread. If not, the program has no way to create additional threads and must therefore be single-threaded. This optimization applies to all the Gnulib multithreading API (locks, thread-local storage, and more).
  • The thread-optim module, on ELF systems (glibc, musl libc, FreeBSD, NetBSD, OpenBSD, Solaris, Android), allows your code to skip locking between threads (regardless which of the three multithreading APIs you use). You need extra code for this: include the "thread-optim.h" header file, and use the macro gl_multithreaded like this: 
    bool mt = gl_multithreaded ();
if (mt) gl_lock_lock (some_lock);
...
if (mt) gl_lock_unlock (some_lock);
  • You may use the unlocked-io module if you want the FILE stream functions getc, putc, etc. to use unlocked I/O if available, throughout the package. Unlocked I/O can improve performance, sometimes dramatically. But unlocked I/O is safe only in processes in which two threads never simultaneously access the same FILE stream.

    You need extra code for this optimization to be effective: include the "unlocked-io.h" header file. Some Gnulib modules that do operations on FILE streams have these preparations already included.

  • You may define the C macro GNULIB_REGEX_SINGLE_THREAD, if all the programs in your package invoke the functions of the regex module only from a single thread.
  • You may define the C macro GNULIB_MBRTOWC_SINGLE_THREAD, if all the programs in your package invoke the functions mbrtowc, mbrtoc32, and the functions of the regex module only from a single thread. (The regex module uses mbrtowc under the hood.)
  • You may define the C macro GNULIB_WCHAR_SINGLE_LOCALE, if all the programs in your package set the locale early and
    • don’t change the locale after it has been initialized, and
    • don’t call locale sensitive functions (mbrtowc, wcwidth, etc.) before the locale has been initialized.

    This macro optimizes the functions mbrtowc, mbrtoc32, and wcwidth. You can get this macro defined by including the Gnulib module wchar-single.

  • You may define the C macro GNULIB_SIGPROCMASK_SINGLE_THREAD, if all the package’s programs call the following functions only from a single thread: pthread_sigmask, sigaction, signal, sigpending. Regardless of whether this macro is defined, only single-threaded processes should call the sigprocmask function itself (see sigprocmask). The macro is named after sigprocmask because it affects Gnulib’s implementation of sigprocmask on native Windows, the only platform where the macro has any effect, and the other functions’ Gnulib implementations use Gnulib sigprocmask on native Windows.
  • You may define the C macro GNULIB_EXCLUDE_SINGLE_THREAD, if all the programs in your package invoke the functions of the exclude module only from a single thread.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

17 Strings and Characters

This chapter describes the APIs for strings and characters, provided by Gnulib.

Next: , Up: Strings and Characters   [Contents][Index]

17.1 Strings

Several possible representations exist for the representation of strings in memory of a running C program.

Next: , Up: Strings   [Contents][Index]

17.1.1 The C string representation

The classical representation of a string in C is a sequence of characters, where each character takes up one or more bytes, followed by a terminating NUL byte. This representation is used for strings that are passed by the operating system (in the argv argument of main, for example) and for strings that are passed to the operating system (in system calls such as open). The C type to hold such strings is ‘char *’ or, in places where the string shall not be modified, ‘const char *’. There are many C library functions, standardized by ISO C and POSIX, that assume this representation of strings.

A character encoding, or encoding for short, describes how the elements of a character set are represented as a sequence of bytes. For example, in the ASCII encoding, the UNDERSCORE character is represented by a single byte, with value 0x5F. As another example, the COPYRIGHT SIGN character is represented:

  • in the ISO-8859-1 encoding, by the single byte 0xA9,
  • in the UTF-8 encoding, by the two bytes 0xC2 0xA9,
  • in the GB18030 encoding, by the four bytes 0x81 0x30 0x84 0x38.

Note: The ‘char’ type may be signed or unsigned, depending on the platform. When we talk about the "byte 0xA9" we actually mean the char object whose value is (char) 0xA9; we omit the cast to char in this documentation, for brevity.

In POSIX, the character encoding is determined by the locale. The locale is some environmental attribute that the user can choose.

Depending on the encoding, in general, every character is represented by one or more bytes (up to 4 bytes in practice – but use MB_LEN_MAX instead of the number 4 in the code). When every character is represented by only 1 byte, we speak of an “unibyte locale”, otherwise of a “multibyte locale”.

It is important to realize that the majority of Unix installations nowadays use UTF-8 as locale encoding; therefore, the majority of users are using multibyte locales.

Three important facts to remember are:

A ‘char’ is a byte, not a character.

As a consequence:

  • The <ctype.h> API, that was designed only with unibyte encodings in mind, is useless nowadays for general text processing; it does not work in multibyte locales.
  • The strlen function does not return the number of characters in a string. Nor does it return the number of screen columns occupied by a string after it is output. It merely returns the number of bytes occupied by a string.
  • Truncating a string, for example, with strncpy, can have the effect of truncating it in the middle of a multibyte character. Such a string will, when output, have a garbled character at its end, often represented by a hollow box.

Multibyte does not imply UTF-8 encoding.

While UTF-8 is the most common multibyte encoding, GB18030 is also a supported locale encoding on GNU systems (mostly because it is a Chinese government standard, last revised in 2022).

Searching for a character in a string is not the same as searching for a byte in the string.

Take the above example of COPYRIGHT SIGN in the GB18030 encoding: A byte search will find the bytes '0' and '8' in this string. But a search for the character "0" or "8" in the string "©" must, of course, report “not found”.

As a consequence:

  • strchr and strrchr do not work with multibyte strings if the locale encoding is GB18030 and the character to be searched is a digit.
  • strstr does not work with multibyte strings if the locale encoding is different from UTF-8.
  • strcspn, strpbrk, strspn cannot work correctly in multibyte locales: they assume the second argument is a list of single-byte characters. Even in this simple case, they do not work with multibyte strings if the locale encoding is GB18030 and one of the characters to be searched is a digit.
  • strsep and strtok_r do not work with multibyte strings unless all of the delimiter characters are ASCII characters < 0x30.
  • The strcasecmp, strncasecmp, and strcasestr functions do not work with multibyte strings.

Workarounds can be found in Gnulib, in the form of mbs* API functions:

  • Gnulib has functions mbslen and mbswidth that can be used instead of strlen when the number of characters or the number of screen columns of a string is requested.
  • Gnulib has functions mbschr and mbsrrchr that are like strchr and strrchr, but work in multibyte locales.
  • Gnulib has a function mbsstr that is like strstr, but works in multibyte locales.
  • Gnulib has functions mbscspn, mbspbrk, mbsspn that are like strcspn, strpbrk, strspn, but work in multibyte locales.
  • Gnulib has functions mbssep and mbstok_r that are like strsep and strtok_r but work in multibyte locales.
  • Gnulib has functions mbscasecmp, mbsncasecmp, mbspcasecmp, and mbscasestr that are like strcasecmp, strncasecmp, and strcasestr, but work in multibyte locales. Still, the function ulc_casecmp is preferable to these functions.

A C string can contain encoding errors.

Not every NUL-terminated byte sequence represents a valid multibyte string. Byte sequences can contain encoding errors, that is, bytes or byte sequences that are invalid and do not represent characters.

String functions like mbscasecmp and strcoll whose behavior depends on encoding have unspecified behavior on strings containing encoding errors, unless the behavior is specifically documented. If an application needs a particular behavior on these strings it can iterate through them itself, as described in the next subsection.

Next: , Previous: , Up: Strings   [Contents][Index]

17.1.2 Iterating through strings

For complex string processing, string functions may not be enough, and you need to iterate through a string while processing each (possibly multibyte) character or encoding error in turn. Gnulib has several modules for iterating forward through a string in this way. Backward iteration, that is, from the string’s end to start, is not provided, as it is too hairy in general.

  • The mbiter module iterates through a string whose length is already known. The string can contain NULs and encoding errors.
  • The mbiterf module is like mbiter except it is more complex and typically faster.
  • The mbuiter module iterates through a C string whose length is not a-priori known. The string can contain encoding errors and is terminated by the first NUL.
  • The mbuiterf module is like mbuiter except it is more complex and typically faster.
  • The mcel module is simpler than mbiter and mbuiter and can be faster than even mbiterf and mbuiterf. It can iterate through either strings whose length is known, or C strings, or strings terminated by other ASCII characters < 0x30.
  • The mcel-prefer module is like mcel except that it causes some other modules to be based on mcel instead of on the mbiter family.

The choice of modules depends on the application’s needs. The mbiter module family is more suitable for applications that treat some sequences of two or more bytes as a single encoding error, and for applications that need to support obsolescent encodings on non-GNU platforms, such as CP864, EBCDIC, Johab, and Shift JIS. In this module family, mbuiter and mbuiterf are more suitable than mbiter and mbiterf when arguments are C strings, lengths are not already known, and it is highly likely that only the first few multibyte characters need to be inspected.

The mcel module is simpler and can be faster than the mbiter family, and is more suitable for applications that do not need the mbiter family’s special features.

The mcel-prefer module is like mcel except that it also causes some other modules, such as mbscasecmp, to use mcel rather than the mbiter family. This can be simpler and faster. However, it does not support the obsolescent encodings, and it may behave differently on data containing encoding errors where behavior is unspecified or undefined, because in mcel each encoding error is a single byte whereas in the mbiter family a single encoding error can contain two or more bytes.

If a package uses mcel-prefer, it may also want to give gnulib-tool one or more of the options --avoid=mbiter, --avoid=mbiterf, --avoid=mbuiter and --avoid=mbuiterf, to avoid packaging modules that are not needed.

Next: , Previous: , Up: Strings   [Contents][Index]

17.1.3 Strings with NUL characters

The GNU Coding Standards, section https://www.gnu.org/prep/standards/html_node/Semantics.html, specifies:

Utilities reading files should not drop NUL characters, or any other nonprinting characters.

When it is a requirement to store NUL characters in strings, a variant of the C strings is needed. Gnulib offers a “string descriptor” type for this purpose. See Handling strings with NUL characters.

All remarks regarding encodings and multibyte characters in the previous section apply to string descriptors as well.

Next: , Previous: , Up: Strings   [Contents][Index]

17.1.4 Character and String Functions in C Locale

The functions in this section are similar to the generic string functions from the standard C library, except that

  • They behave as if the locale was set to the "C" locale, even when the locale is different, and/or
  • They are specially optimized for the case where all characters are plain ASCII characters.

The functions are provided by the following modules.

Next: , Up: Character and String Functions in C Locale   [Contents][Index]

17.1.4.1 c-ctype

The c-ctype module contains functions operating on single-byte characters, like the functions in <ctype.h>, that operate as if the locale encoding was ASCII. (The "C" locale on many systems has the locale encoding "ASCII".)

The functions are: 

extern bool c_isascii (int c);

extern bool c_isalnum (int c);
extern bool c_isalpha (int c);
extern bool c_isblank (int c);
extern bool c_iscntrl (int c);
extern bool c_isdigit (int c);
extern bool c_islower (int c);
extern bool c_isgraph (int c);
extern bool c_isprint (int c);
extern bool c_ispunct (int c);
extern bool c_isspace (int c);
extern bool c_isupper (int c);
extern bool c_isxdigit (int c);

extern int c_tolower (int c);
extern int c_toupper (int c);

These functions assign properties only to ASCII characters.

The c argument can be a char or unsigned char value, whereas the corresponding functions in <ctype.h> take an argument that is actually an unsigned char value.

The c_is* functions return ‘bool’, where the corresponding functions in <ctype.h> return ‘int’ for historical reasons.

Note: The <ctype.h> functions support only unibyte locales.

Next: , Previous: , Up: Character and String Functions in C Locale   [Contents][Index]

17.1.4.2 c-strcaseeq

The c-strcaseeq module contains an optimized case-insensitive string comparison function operating on single-byte character strings, that operate as if the locale encoding was ASCII. (The "C" locale on many systems has the locale encoding "ASCII".)

The functions is actually implemented as a macro: 

extern int STRCASEEQ (const char *s1, const char *s2,
                      int s20, int s21, int s22, int s23, int s24, int s25,
                      int s26, int s27, int s28);

s2 should be a short literal ASCII string, and s20, s21, ... the individual characters of s2.

For case conversion here, only ASCII characters are considered to be upper case or lower case.

Next: , Previous: , Up: Character and String Functions in C Locale   [Contents][Index]

17.1.4.3 c-strcasecmp

The c-strcasecmp module contains a case-insensitive string comparison function operating on single-byte character strings, like the functions in <strings.h>, that operate as if the locale encoding was ASCII. (The "C" locale on many systems has the locale encoding "ASCII".)

The function is: 

extern int c_strcasecmp (const char *s1, const char *s2);

For case conversion here, only ASCII characters are considered to be upper case or lower case.

Note: The function strcasecmp from <strings.h> supports only unibyte locales; for multibyte locales, you need the function mbscasecmp.

Next: , Previous: , Up: Character and String Functions in C Locale   [Contents][Index]

17.1.4.4 c-strncasecmp

The c-strncasecmp module contains a case-insensitive string comparison function operating on single-byte character strings, like the functions in <strings.h>, that operate as if the locale encoding was ASCII. (The "C" locale on many systems has the locale encoding "ASCII".)

The function is: 

extern int c_strncasecmp (const char *s1, const char *s2, size_t n);

For case conversion here, only ASCII characters are considered to be upper case or lower case.

Note: The function strncasecmp from <strings.h> supports only unibyte locales; for multibyte locales, you need the function mbsncasecmp or mbspcasecmp.

Next: , Previous: , Up: Character and String Functions in C Locale   [Contents][Index]

17.1.4.5 c-strcasestr

The c-strcasestr module contains a case-insensitive string search function operating on single-byte character strings, that operate as if the locale encoding was ASCII. (The "C" locale on many systems has the locale encoding "ASCII".)

The function is: 

extern char *c_strcasestr (const char *haystack, const char *needle);

For case conversion here, only ASCII characters are considered to be upper case or lower case.

Note: The function strcasestr from <string.h> supports only unibyte locales; for multibyte locales, you need the function mbscasestr.

Next: , Previous: , Up: Character and String Functions in C Locale   [Contents][Index]

17.1.4.6 c-strstr

The c-strstr module contains a substring search function operating on single-byte character strings, that operate as if the locale encoding was ASCII. (The "C" locale on many systems has the locale encoding "ASCII".)

The function is: 

extern char *c_strstr (const char *haystack, const char *needle);

Note: The function strstr from <string.h> supports only unibyte locales; for multibyte locales, you need the function mbsstr.

Next: , Previous: , Up: Character and String Functions in C Locale   [Contents][Index]

17.1.4.7 c-strtod

The c-strtod module contains a string to number (‘double’) conversion function operating on single-byte character strings, that operates as if the locale encoding was ASCII. (The "C" locale on many systems has the locale encoding "ASCII".)

The function is: 

extern double c_strtod (const char *string, char **endp);

In particular, only a period ‘.’ is accepted as decimal point, even when the current locale’s notion of decimal point is a comma ‘,’, and no characters outside the basic character set are accepted.

On platforms without strtod_l, this function is not safe for use in multi-threaded processes since it calls setlocale.

Previous: , Up: Character and String Functions in C Locale   [Contents][Index]

17.1.4.8 c-strtold

The c-strtold module contains a string to number (‘long double’) conversion function operating on single-byte character strings, that operates as if the locale encoding was ASCII. (The "C" locale on many systems has the locale encoding "ASCII".)

The function is: 

extern long double c_strtold (const char *string, char **endp);

In particular, only a period ‘.’ is accepted as decimal point, even when the current locale’s notion of decimal point is a comma ‘,’.

Previous: , Up: Strings   [Contents][Index]

17.1.5 Comparison of string APIs

This table summarizes the API functions available for strings, in POSIX and in Gnulib.

unibyte strings onlyassume C localemultibyte stringsmultibyte strings with NULswide character strings32-bit wide character strings
strlenstrlenmbslensd_lengthwcslenu32_strlen
strnlenstrnlenmbsnlen–wcsnlenu32_strnlen, u32_mbsnlen
strcmpstrcmpstrcmpsd_cmpwcscmpu32_strcmp
strncmpstrncmpstrncmp–wcsncmpu32_strncmp
strcasecmpstrcasecmpmbscasecmp–wcscasecmpu32_casecmp
strncasecmpstrncasecmpmbsncasecmp, mbspcasecmp–wcsncasecmpu32_casecmp
strcollstrcmpstrcoll–wcscollu32_strcoll
strxfrm–strxfrm–wcsxfrm–
strchrstrchrmbschrsd_indexwcschru32_strchr
strrchrstrrchrmbsrchrsd_last_indexwcsrchru32_strrchr
strstrstrstrmbsstrsd_containswcsstru32_strstr
strcasestrstrcasestrmbscasestr–––
str_startswithstr_startswithmbs_startswithsd_startswith–u32_startswith
str_endswithstr_endswithmbs_endswithsd_endswith–u32_endswith
strspnstrspnmbsspn–wcsspnu32_strspn
strcspnstrcspnmbscspn–wcscspnu32_strcspn
strpbrkstrpbrkmbspbrk–wcspbrku32_strpbrk
strtok_rstrtok_rmbstok_r–wcstoku32_strtok
strsepstrsepmbssep–––
strcpystrcpystrcpysd_copywcscpyu32_strcpy
stpcpystpcpystpcpy–wcpcpyu32_stpcpy
strncpystrncpystrncpy–wcsncpyu32_strncpy
stpncpystpncpystpncpy–wcpncpyu32_stpncpy
strcatstrcatstrcatsd_concatwcscatu32_strcat
strncatstrncatstrncat–wcsncatu32_strncat
freefreefreesd_freefreefree
strdupstrdupstrdupsd_copywcsdupu32_strdup
strndupstrndupstrndup–––
mbswidthmbswidthmbswidth–wcswidthc32swidth, u32_strwidth
strtolstrtolstrtol–––
strtoulstrtoulstrtoul–––
strtollstrtollstrtoll–––
strtoullstrtoullstrtoull–––
strtoimaxstrtoimaxstrtoimax–wcstoimax–
strtoumaxstrtoumaxstrtoumax–wcstoumax–
strtof–strtof–––
strtodc_strtodstrtod–––
strtoldc_strtoldstrtold–––
strfromf–strfromf–––
strfromd–strfromd–––
strfroml–strfroml–––
––––mbstowcsmbstoc32s
––––mbsrtowcsmbsrtoc32s
––––mbsnrtowcsmbsnrtoc32s
––––wcstombsc32stombs
––––wcsrtombsc32srtombs
––––wcsnrtombsc32snrtombs

Previous: , Up: Strings and Characters   [Contents][Index]

17.2 Characters

A character is the elementary unit that strings are made of.

What is a character? “A character is an element of a character set” is sort of a circular definition, but it highlights the fact that it is not merely a number. Although many characters are visually represented by a single glyph, there are characters that, for example, have a different glyph when used at the end of a word than when used inside a word. A character is also not the minimal rendered text processing unit; that is a grapheme cluster and in general consists of one or more characters. If you want to know more about the concept of character and various concepts associated with characters, refer to the Unicode standard.

For the representation in memory of a character, various types have been in use, and some of them were failures: char and wchar_t were invented for this purpose, but are not the right types. char32_t is the right type (successor of wchar_t); and mbchar_t (defined by Gnulib) is an alternative for specific kinds of processing.

Next: , Up: Characters   [Contents][Index]

17.2.1 The char type

The char type is in the C language since the beginning in the 1970ies, but – due to its limitation of 256 possible values – is no longer the adequate type for storing a character.

Technically, it is still adequate in unibyte locales. But since most locales nowadays are multibyte locales, it makes no sense to write a program that runs only in unibyte locales.

ISO C and POSIX standardized an API for characters of type char, in <ctype.h>. This API is nowadays useless and obsolete, when it comes to general text processing.

The important lessons to remember are:

A ‘char’ is just the elementary storage unit for a string, not a character.

Never use <ctype.h>!

Next: , Previous: , Up: Characters   [Contents][Index]

17.2.2 The wchar_t type

The ISO C and POSIX standard creators made an attempt to overcome the dead end regarding the char type. They introduced

  • a type ‘wchar_t’, designed to encapsulate a character,
  • a “wide string” type ‘wchar_t *’, with some API functions declared in <wchar.h>, and
  • functions declared in <wctype.h> that were meant to supplant the ones in <ctype.h>.

Unfortunately, this API and its implementation has numerous problems:

  • On Windows platforms and on AIX in 32-bit mode, wchar_t is a 16-bit type. This means that it can never accommodate an entire Unicode character. Either the wchar_t * strings are limited to characters in UCS-2 (the “Basic Multilingual Plane” of Unicode), or – if wchar_t * strings are encoded in UTF-16 – a wchar_t represents only half of a character in the worst case, making the <wctype.h> functions pointless.
  • On Solaris and FreeBSD, the wchar_t encoding is locale dependent and undocumented. This means, if you want to know any property of a wchar_t character, other than the properties defined by <wctype.h> – such as whether it’s a dash, currency symbol, paragraph separator, or similar –, you have to convert it to char * encoding first, by use of the function wctomb.
  • When you read a stream of wide characters, through the functions fgetwc and fgetws, and when the input stream/file is not in the expected encoding, you have no way to determine the invalid byte sequence and do some corrective action. If you use these functions, your program becomes “garbage in - more garbage out” or “garbage in - abort”.

As a consequence, it is better to use multibyte strings. Such multibyte strings can bypass limitations of the wchar_t type, if you use functions defined in Gnulib and GNU libunistring for text processing. They can also faithfully transport malformed characters that were present in the input, without requiring the program to produce garbage or abort.

Next: , Previous: , Up: Characters   [Contents][Index]

17.2.3 The char32_t type

The ISO C and POSIX standard creators then introduced the char32_t type. In ISO C 11, it was conceptually a “32-bit wide character” type. In ISO C 23, its semantics has been further specified: A char32_t value is a Unicode code point.

Thus, the char32_t type is not affected the problems that plague the wchar_t type.

The char32_t type and its API are defined in the <uchar.h> header file.

ISO C and POSIX specify only the basic functions for the char32_t type, namely conversion of a single character (mbrtoc32 and c32rtomb). For convenience, Gnulib adds API for classification and case conversion of characters.

GNU libunistring can also be used on char32_t values. Since char32_t is the same as uint32_t, all u32_* functions of GNU libunistring are applicable to arrays of char32_t values.

On glibc systems, use of the 32-bit wide strings (char32_t[]) is exactly as efficient as the use of the older wide strings (wchar_t[]). This is possible because on glibc, wchar_t values already always were 32-bit and Unicode code points. mbrtoc32 is just an alias of mbrtowc. The Gnulib *c32* functions are optimized so that on glibc systems they immediately redirect to the corresponding *wc* functions.

Gnulib implements the ISO C 23 semantics of char32_t when you import the ‘uchar-h-c23’ module. Without this module, it implements only the ISO C 11 semantics; the effect is that on some platforms (macOS, FreeBSD, NetBSD, Solaris) a char32_t value is the same as a wchar_t value, not a Unicode code point. Thus, when you want to pass char32_t values to GNU libunistring or to some Unicode centric Gnulib functions, you need the ‘uchar-h-c23’ module in order to do so without portability problems.

Next: , Previous: , Up: Characters   [Contents][Index]

17.2.4 The mbchar_t type

Gnulib defines an alternate way to encode a multibyte character: mbchar_t. Its main feature is the ability to process a string or stream with some malformed characters without reporting an error.

The type mbchar_t, defined in "mbchar.h", holds a character in both the multibyte and the 32-bit wide character representation. In case of a malformed character only the multibyte representation is used.

Up: The mbchar_t type   [Contents][Index]

17.2.4.1 Reading multibyte strings

If you want to process (possibly multibyte) characters while reading them from a FILE * stream, without reading them into a string first, the mbfile module is made for this purpose.

Previous: , Up: Characters   [Contents][Index]

17.2.5 Comparison of character APIs

This table summarizes the API functions available for characters, in POSIX and in Gnulib.

unibyte characterassume C localewide character32-bit wide charactermbchar_t character
== '\0'== '\0'== L'\0'== 0mb_isnul
========mb_equal
isalnumc_isalnumiswalnumc32isalnummb_isalnum
isalphac_isalphaiswalphac32isalphamb_isalpha
isblankc_isblankiswblankc32isblankmb_isblank
iscntrlc_iscntrliswcntrlc32iscntrlmb_iscntrl
isdigitc_isdigitiswdigitc32isdigitmb_isdigit
isgraphc_isgraphiswgraphc32isgraphmb_isgraph
islowerc_isloweriswlowerc32islowermb_islower
isprintc_isprintiswprintc32isprintmb_isprint
ispunctc_ispunctiswpunctc32ispunctmb_ispunct
isspacec_isspaceiswspacec32isspacemb_isspace
isupperc_isupperiswupperc32isuppermb_isupper
isxdigitc_isxdigitiswxdigitc32isxdigitmb_isxdigit
––wctypec32_get_type_test–
––iswctypec32_apply_type_test–
tolowerc_tolowertowlowerc32tolower–
toupperc_touppertowupperc32toupper–
––wctransc32_get_mapping–
––towctransc32_apply_mapping–
––wcwidthc32widthmb_width

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

18 Particular Modules

Next: , Up: Particular Modules   [Contents][Index]

18.1 alloca

The alloca module provides for a function alloca which allocates memory on the stack, where the system allows it. A memory block allocated with alloca exists only until the function that calls alloca returns or exits abruptly.

There are a few systems where this is not possible: HP-UX systems, and some other platforms when the C++ compiler is used. On these platforms the alloca module provides a malloc based emulation. This emulation will not free a memory block immediately when the calling function returns, but rather will wait until the next alloca call from a function with the same or a shorter stack length. Thus, in some cases, a few memory blocks will be kept although they are not needed any more.

The user can #include <alloca.h> and use alloca on all platforms. Note that the #include <alloca.h> must be the first one after the autoconf-generated config.h, for AIX 3 compatibility. Thanks to IBM for this nice restriction!

Note that GCC 3.1 and 3.2 can inline functions that call alloca. When this happens, the memory blocks allocated with alloca will not be freed until the end of the calling function. If this calling function runs a loop calling the function that uses alloca, the program easily gets a stack overflow and crashes. To protect against this compiler behaviour, you can mark the function that uses alloca with the following attribute: 

#ifdef __GNUC__
__attribute__ ((__noinline__))
#endif

An alternative to this module is the ‘alloca-opt’ module.

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.2 alloca-opt

The alloca-opt module provides for a function alloca which allocates memory on the stack, where the system allows it. A memory block allocated with alloca exists only until the function that calls alloca returns or exits abruptly.

There are a few systems where this is not possible: HP-UX systems, and some other platforms when the C++ compiler is used. On these platforms the alloca-opt module provides no replacement, just a preprocessor macro HAVE_ALLOCA.

The user can #include <alloca.h> on all platforms, and use alloca on those platforms where the preprocessor macro HAVE_ALLOCA evaluates to true. If HAVE_ALLOCA is false, the code should use a heap-based memory allocation based on malloc or (in C++) new. Note that the #include <alloca.h> must be the first one after the autoconf-generated config.h, for AIX 3 compatibility. Thanks to IBM for this nice restriction!

Note that GCC 3.1 and 3.2 can inline functions that call alloca. When this happens, the memory blocks allocated with alloca will not be freed until the end of the calling function. If this calling function runs a loop calling the function that uses alloca, the program easily gets a stack overflow and crashes. To protect against this compiler behaviour, you can mark the function that uses alloca with the following attribute: 

#ifdef __GNUC__
__attribute__ ((__noinline__))
#endif

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.3 Safe Allocation Macros

The standard C library malloc/realloc/calloc/free APIs are prone to a number of common coding errors. The safe-alloc module provides macros that make it easier to avoid many of them. It still uses the standard C allocation functions behind the scenes.

This module is obsolete, as it does not seem to have caught on in practice and some of its features could not be ported to unusual platforms.

Some of the memory allocation mistakes that are commonly made are

  • passing the incorrect number of bytes to malloc, especially when allocating an array,
  • unchecked integer overflow when calculating array sizes,
  • fail to check the return value of malloc and realloc for errors,
  • forget to fully initialize memory just allocated with malloc,
  • duplicate calls to free by forgetting to set the pointer variable to NULL,
  • leaking memory in calls to realloc when that call fails.

The safe-alloc module addresses these problems in the following way:

  • It defines macros that wrap around the standard C allocation functions. That makes it possible to use the compiler’s knowledge of the size of objects for allocation; it also allows setting pointers passed in as arguments when appropriate.
  • It uses return values only for a success/failure error condition flag, and annotates them with GCC’s __warn_unused_result__ attribute.
  • When allocating a fresh array, it uses calloc instead of malloc so that the array’s contents are zeroed. However, memory added to an already-existing array is uninitialized.
Macro: int ALLOC (ptr)

Allocate sizeof *ptr bytes of memory and store the address of allocated memory in ptr. Fill the newly allocated memory with zeros.

Returns −1 on failure, 0 on success.

Macro: int ALLOC_N (ptr, count)

Allocate an array of count elements, each sizeof *ptr bytes long, and store the address of allocated memory in ptr. Fill the newly allocated memory with zeros.

Returns −1 on failure, 0 on success.

Macro: int ALLOC_N_UNINITIALIZED (ptr, count)

Allocate an array of count elements, each sizeof *ptr bytes long, and store the address of allocated memory in ptr. The allocated memory is not initialized.

Returns −1 on failure, 0 on success.

Macro: void FREE (ptr)

Free the memory stored in ptr and set ptr to NULL.

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.4 Attributes

The module ‘attribute’ provides a header file attribute.h that defines macros related to C and C++ attributes and the GCC __attribute__ keyword.

Here is an example of its use: 

#include <attribute.h>

NODISCARD
extern char *crypt (char const *, char const *)
  ATTRIBUTE_NOTHROW ATTRIBUTE_LEAF ATTRIBUTE_NONNULL ((1, 2));

NODISCARD expands to [[nodiscard]] if the compiler supports this C23 syntax, otherwise to __attribute__ ((__warn_unused_result__)) if the compiler is a recent-enough GCC or GCC-like compiler, otherwise to nothing. ATTRIBUTE_NOTHROW expands to __attribute__ ((__nothrow__)) if the compiler is a recent-enough GCC or GCC-like compiler, and to nothing otherwise. Similarly for ATTRIBUTE_LEAF. ATTRIBUTE_NONNULL ((1, 2)) expands to __attribute__ ((__nonnull__ (1, 2))) if the compiler is recent-enough GCC, and to nothing otherwise.

Most of these attribute names begin with ATTRIBUTE_. A few do not, because they are part of C23 and their names are not likely to clash with other macro names. These macros are DEPRECATED, FALLTHROUGH, MAYBE_UNUSED, and NODISCARD, which can be defined to [[deprecated]] etc. on C23 platforms. Also, these exceptional macros should be placed at the start of function declarations, whereas the ATTRIBUTE_* macros can be placed at the end.

The module also defines the macro UNNAMED, designed for function parameters that are never used, whereas the MAYBE_UNUSED attribute is better suited for parameters that might or might not be unused depending on preprocessor macro settings. For example: 

int
f (int a, MAYBE_UNUSED int b, int UNNAMED (c))
{
  int r = a;
#ifdef B_FEATURE
  r |= b;
#endif
  return r;
}

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.5 Compile-time Assertions

The module ‘verify’ provides a header file verify.h that defines macros related to compile-time verification.

Two of these macros are verify (V) and verify_expr (V, EXPR). Both accept an integer constant expression argument V and verify that it is nonzero. If not, a compile-time error results.

These two macros implement compile-time tests, as opposed to the standard assert macro which supports only runtime tests. Since the tests occur at compile-time, they are more reliable, and they require no runtime overhead.

verify (V); is a declaration; it can occur outside of functions. In contrast, verify_expr (V, EXPR) is an expression that returns the value of EXPR; it can be used in macros that expand to expressions. If EXPR is an integer constant expression, then verify_expr (V, EXPR) is also an integer constant expression. Although EXPR and verify_expr (V, EXPR) are guaranteed to have the same side effects and value and type (after integer promotion), they need not have the same type if EXPR’s type is an integer that is narrower than int or unsigned int.

V should be an integer constant expression in the sense of the C standard. Its leaf operands should be integer, enumeration, or character constants; or sizeof expressions that return constants; or floating constants that are the immediate operands of casts. Outside a sizeof subexpression, V should not contain any assignments, function calls, comma operators, casts to non-integer types, or subexpressions whose values are outside the representable ranges for their types. If V is not an integer constant expression, then a compiler might reject a usage like ‘verify (V);’ even when V is nonzero.

Although the standard assert macro is a runtime test, C23 and C++17 specify a builtin static_assert (V), which differs from verify in two major ways. First, it can also be used within a struct or union specifier, in place of an ordinary member declaration. Second, it allows the programmer to specify, as an optional second argument, a compile-time diagnostic as a string literal. If your program is not intended to be portable to compilers that lack C23 or C++17 static_assert, the only advantage of verify is that its name is a bit shorter.

The verify.h header defines one more macro, assume (E), which expands to an expression of type void that causes the compiler to assume that E yields a nonzero value. E should be a scalar expression, and should not have side effects; it may or may not be evaluated. The behavior is undefined if E would yield zero. The main use of assume is optimization, as the compiler may be able to generate better code if it assumes E. For best results, E should be simple enough that a compiler can determine that it has no side effects: if E calls an external function or accesses volatile storage the compiler may not be able to optimize E away and assume (E) may therefore slow down the program.

Here are some example uses of these macros. 

#include <verify.h>

#include <limits.h>
#include <time.h>



/* Verify that time_t is an integer type.  */
verify ((time_t) 1.5 == 1);



/* Verify that time_t is no smaller than int.  */
verify (sizeof (int) <= sizeof (time_t));



/* Verify that time_t is signed.  */
verify ((time_t) -1 < 0);



/* Verify that time_t uses two's complement representation.  */
verify (~ (time_t) -1 == 0);



/* Return the maximum value of the integer type T,
   verifying that T is an unsigned integer type.
   The cast to (T) is outside the call to verify_expr
   so that the result is of type T
   even when T is narrower than unsigned int.  */
#define MAX_UNSIGNED_VAL(t) \
   ((t) verify_expr (0 < (t) -1, -1))



/* Return T divided by CHAR_MAX + 1, where behavior is
   undefined if T < 0.  In the common case where CHAR_MAX
   is 127 the compiler can therefore implement the division
   by shifting T right 7 bits, an optimization that would
   not be valid if T were negative.  */
time_t
time_index (time_t t)
{
  assume (0 <= t);
  return t / (CHAR_MAX + 1);
}

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.6 Non-returning Functions

A "non-returning" function is a function which cannot return normally. Instead of returning, it can loop forever, or it can transfer control via abort, execvp, exit, longjmp, throw (in C++), or similar mechanisms. Non-returning functions are declared with a void return type.

It helps the compiler’s ability to emit sensible warnings, following data-flow analysis, to declare which functions are non-returning. It can also help generate more-efficient code, as there is no need to save a return address when calling a non-returning function.

Gnulib has multiple ways to support such a declaration:

  • The _Noreturn keyword. No modules are needed, as Gnulib arranges for <config.h> to define _Noreturn to an appropriate replacement on platforms lacking it. Unfortunately, although this approach works for all current C versions, the _Noreturn keyword is obsolescent in C23.
  • The ‘noreturn’ module. It provides a way to put this declaration at function declarations, at function definitions, and in function pointer types. The identifiers to use are:
    • _GL_NORETURN_FUNC for use in function declarations and function definitions.
    • _GL_NORETURN_FUNCPTR for use on function pointers.

    The include file is <noreturn.h>.

Which of the approaches to use? If the non-returning functions you have to declare are unlikely to be accessed through function pointers, you should use _Noreturn; otherwise the module noreturn provides for better data-flow analysis and thus for better warnings.

There is also an obsolete stdnoreturn-h module, but its use is no longer recommended.

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.7 Integer Properties

The intprops module consists of an include file <intprops.h> that defines several macros useful for testing properties of integer types.

Integer overflow is a common source of problems in programs written in C and other languages. In some cases, such as signed integer arithmetic in C programs, the resulting behavior is undefined, and practical platforms do not always behave as if integers wrap around reliably. In other cases, such as unsigned integer arithmetic in C, the resulting behavior is well-defined, but programs may still misbehave badly after overflow occurs.

Many techniques have been proposed to attack these problems. These include precondition testing, wraparound behavior where signed integer arithmetic is guaranteed to be modular, saturation semantics where overflow reliably yields an extreme value, undefined behavior sanitizers where overflow is guaranteed to trap, and various static analysis techniques.

Gnulib supports wraparound arithmetic and precondition testing, as these are relatively easy to support portably and efficiently. There are two families of precondition tests: the first, for integer types, is easier to use, while the second, for integer ranges, has a simple and straightforward portable implementation.

Like other Gnulib modules, the implementation of the intprops module assumes that integers use a two’s complement representation, but it does not assume that signed integer arithmetic wraps around. See Other portability assumptions made by Gnulib.

Next: , Up: Integer Properties   [Contents][Index]

18.7.1 Arithmetic Type Properties

TYPE_IS_INTEGER (t) is an arithmetic constant expression that yields 1 if the arithmetic type t is an integer type, 0 otherwise. bool counts as an integer type.

TYPE_SIGNED (t) is an arithmetic constant expression that yields 1 if the real type t is a signed integer type or a floating type, 0 otherwise. If t is an integer type, TYPE_SIGNED (t) is an integer constant expression.

EXPR_SIGNED (e) yields 1 if the real expression e has a signed integer type or a floating type, 0 otherwise. If e is an integer constant expression or an arithmetic constant expression, EXPR_SIGNED (e) is likewise. The expression e is not evaluated, and EXPR_SIGNED (e) is typically optimized to a constant.

Example usage: 

#include <intprops.h>
#include <sys/types.h>

enum
{
  clock_t_is_integer = TYPE_IS_INTEGER (clock_t),
  uid_t_is_signed = TYPE_SIGNED (uid_t)
};

int
CLOCKS_PER_SEC_is_signed (void)
{
  return EXPR_SIGNED (CLOCKS_PER_SEC);
}

Next: , Previous: , Up: Integer Properties   [Contents][Index]

18.7.2 Arithmetic Type Conversion

Here are some ways in C to convert an arithmetic expression e to a possibly different arithmetic type t.

  • An explicit conversion like ((t) e) is powerful and can therefore be dangerous, because the conversion can succeed even if neither e nor t happens to have an arithmetic type. For example, if e is a pointer, ((long int) e) will do a conversion even if that was not the intent.
  • An implicit conversion like t v = e; is less powerful, as it does not convert from pointers. However, it can lose information and sign, as in for example int v = -0.9; which sets v to zero.
  • A no-op arithmetic expression like +e is even less powerful, as it preserves value (including sign) because it does only integer promotions. That is, it converts to int if that can represent all values of e’s underlying type, otherwise to unsigned int if that can represent all values, and otherwise it does no conversion.

INT_PROMOTE (e) is an expression with the same value as the arithmetic expression e but with e’s type after any integer promotion. It behaves like +e.

In the following example, using INT_PROMOTE pacifies GCC’s -Wswitch-enum option, and may help human readers see what is going on even if they are not expert in C’s integer promotion rules and might be confused by the simpler switch (+v). 

enum { A = 1, B, C, D, E } v = ...;
switch (INT_PROMOTE (v))
  {
    case A: case C:
      return true;
    default:
      /* Handle all other cases,
         even cases like v == 0.  */
      return false;
  }

Next: , Previous: , Up: Integer Properties   [Contents][Index]

18.7.3 Integer Bounds

INT_BUFSIZE_BOUND (t) is an integer constant expression that is a bound on the size of the string representing an integer type or expression t in decimal notation, including the terminating null character and any leading - character. For example, if INT_BUFSIZE_BOUND (int) is 12, any value of type int can be represented in 12 bytes or less, including the terminating null. The bound is not necessarily tight.

Example usage: 

#include <intprops.h>
#include <stdio.h>
int
int_strlen (int i)
{
  char buf[INT_BUFSIZE_BOUND (int)];
  return sprintf (buf, "%d", i);
}

INT_STRLEN_BOUND (t) is an integer constant expression that is a bound on the length of the string representing an integer type or expression t in decimal notation, including any leading - character. This is one less than INT_BUFSIZE_BOUND (t).

TYPE_MINIMUM (t) and TYPE_MAXIMUM (t) are integer constant expressions equal to the minimum and maximum values of the integer type t. These expressions are of the type t.

Example usage: 

#include <sys/types.h>
#include <intprops.h>
bool
in_off_t_range (long long int a)
{
  return TYPE_MINIMUM (off_t) <= a && a <= TYPE_MAXIMUM (off_t);
}

Next: , Previous: , Up: Integer Properties   [Contents][Index]

18.7.4 Checking Integer Overflow

Signed integer arithmetic has undefined behavior on overflow in C. Although almost all modern computers use two’s complement signed arithmetic that is well-defined to wrap around, C compilers routinely optimize assuming that signed integer overflow cannot occur, which means that a C program cannot easily get at the underlying machine arithmetic. For example: 

if ((a + b < b) == (a < 0))
  a += b;
else
  printf ("overflow\n");

might not work as expected if a and b are signed, because a compiler can assume that signed overflow cannot occur and treat the entire if expression as if it were true. And even if a is unsigned, the expression might not work as expected if b is negative or is wider than a.

The following macros work around this problem by yielding an overflow indication while computing the sum, difference, or product of two integers. For example, if i is of type int, INT_ADD_OK (INT_MAX - 1, 1, &i) sets i to INT_MAX and yields 1, whereas INT_ADD_OK (INT_MAX, 1, &i) yields 0.

Example usage: 

#include <intprops.h>
#include <stdio.h>

/* Compute A * B, reporting whether overflow occurred.  */
void
print_product (long int a, long int b)
{
  long int r;
  if (INT_MULTIPLY_OK (a, b, &r))
    printf ("result is %ld\n", r);
  else
    printf ("overflow\n");
}

These macros work for both signed and unsigned integers, so they can be used with integer types like time_t that may or may not be signed, depending on the platform.

These macros have the following restrictions:

  • Their first two arguments must be integer expressions.
  • Their last argument must be a non-null pointer to an integer.
  • They may evaluate their arguments zero or multiple times, so the arguments should not have side effects.
  • They are not necessarily constant expressions, even if all their arguments are constant expressions.
INT_ADD_OK (a, b, r)

Compute the sum of a and b. If it fits into *r, store it there and yield 1. Otherwise yield 0, possibly modifying *r to an unspecified value. See above for restrictions.

INT_SUBTRACT_OK (a, b, r)

Compute the difference between a and b. If it fits into *r, store it there and yield 1. Otherwise yield 0, possibly modifying *r to an unspecified value. See above for restrictions.

INT_MULTIPLY_OK (a, b, r)

Compute the product of a and b. If it fits into *r, store it there and yield 1. Otherwise yield 0, possibly modifying *r to an unspecified value. See above for restrictions.

Other macros are available if you need wrapped-around results when overflow occurs (see Wraparound Arithmetic with Integers), or if you need to check for overflow in operations other than addition, subtraction, and multiplication (see Integer Type Overflow).

Next: , Previous: , Up: Integer Properties   [Contents][Index]

18.7.5 Wraparound Arithmetic with Integers

Signed integer arithmetic has undefined behavior on overflow in C. Although almost all modern computers use two’s complement signed arithmetic that is well-defined to wrap around, C compilers routinely optimize assuming that signed integer overflow cannot occur, which means that a C program cannot easily get at the underlying machine arithmetic. For example, on a typical machine with 32-bit two’s complement int the expression INT_MAX + 1 does not necessarily yield INT_MIN, because the compiler may do calculations with a 64-bit register, or may generate code that traps on signed integer overflow.

The following macros work around this problem by storing the wraparound value, i.e., the low-order bits of the correct answer, and by yielding an overflow indication. For example, if i is of type int, INT_ADD_WRAPV (INT_MAX, 1, &i) sets i to INT_MIN and yields 1 on a two’s complement machine. See Integer Type Overflow.

Example usage: 

#include <intprops.h>
#include <stdio.h>

/* Print the low order bits of A * B,
   reporting whether overflow occurred.  */
void
print_product (long int a, long int b)
{
  long int r;
  int overflow = INT_MULTIPLY_WRAPV (a, b, &r);
  printf ("result is %ld (%s)\n", r,
          (overflow
           ? "after overflow"
           : "no overflow"));
}

These macros work for both signed and unsigned integers, so they can be used with integer types like time_t that may or may not be signed, depending on the platform.

These macros have the following restrictions:

  • Their first two arguments must be integer expressions.
  • Their last argument must be a non-null pointer to an integer.
  • They may evaluate their arguments zero or multiple times, so the arguments should not have side effects.
  • They are not necessarily constant expressions, even if all their arguments are constant expressions.
INT_ADD_WRAPV (a, b, r)

Store the low-order bits of the sum of a and b into *r. Yield 1 if overflow occurred, 0 if the low-order bits are the mathematically-correct sum. See above for restrictions.

INT_SUBTRACT_WRAPV (a, b, r)

Store the low-order bits of the difference between a and b into *r. Yield 1 if overflow occurred, 0 if the low-order bits are the mathematically-correct difference. See above for restrictions.

INT_MULTIPLY_WRAPV (a, b, r)

Store the low-order bits of the product of a and b into *r. Yield 1 if overflow occurred, 0 if the low-order bits are the mathematically-correct product. See above for restrictions.

If your code includes <intprops.h> only for these _WRAPV macros, you may prefer to use Gnulib’s stdckdint-h module instead, as it supports similar macros that were standardized in C23 and are therefore independent of Gnulib if your code can assume C23 or later. See stdckdint.h.

Other macros are available if you do not need wrapped-around results when overflow occurs (see Checking Integer Overflow), or if you need to check for overflow in operations other than addition, subtraction, and multiplication (see Integer Type Overflow).

Next: , Previous: , Up: Integer Properties   [Contents][Index]

18.7.6 Integer Type Overflow

Although unsigned integer arithmetic wraps around modulo a power of two, signed integer arithmetic has undefined behavior on overflow in C. Almost all modern computers use two’s complement signed arithmetic that is well-defined to wrap around, but C compilers routinely optimize based on the assumption that signed integer overflow cannot occur, which means that a C program cannot easily get at the underlying machine behavior. For example, the signed integer expression (a + b < b) != (a < 0) is not a reliable test for whether a + b overflows, because a compiler can assume that signed overflow cannot occur and treat the entire expression as if it were false.

These macros yield 1 if the corresponding C operators overflow, 0 otherwise. They work correctly on all known practical hosts, and do not rely on undefined behavior due to signed arithmetic overflow. They are integer constant expressions if their arguments are. They are typically easier to use than the integer range overflow macros (see Integer Range Overflow), and they support more operations and evaluation contexts than the integer overflow checking macros (see Checking Integer Overflow) or the wraparound macros (see Wraparound Arithmetic with Integers).

These macros can be tricky to use with arguments narrower than int. For example, in the common case with 16-bit short int and 32-bit int, if a and b are of type short int then INT_MULTIPLY_OVERFLOW (a, b) always yields 0, as a * b cannot overflow due to C’s rule that a and b are widened to int before multiplying. For this reason, often it is better to use the integer overflow checking macros (see Checking Integer Overflow) or the wraparound macros (see Wraparound Arithmetic with Integers) when checking for overflow in addition, subtraction, or multiplication.

Example usage: 

#include <intprops.h>
#include <limits.h>
#include <stdio.h>

/* Print A * B if in range, an overflow
   indicator otherwise.  */
void
print_product (long int a, long int b)
{
  if (INT_MULTIPLY_OVERFLOW (a, b))
    printf ("multiply would overflow");
  else
    printf ("product is %ld", a * b);
}

/* Does the product of two ints always fit
   in a long int?  */
enum {
  INT_PRODUCTS_FIT_IN_LONG
    = ! (INT_MULTIPLY_OVERFLOW
         ((long int) INT_MIN, INT_MIN))
};

These macros have the following restrictions:

  • Their arguments must be integer expressions.
  • They may evaluate their arguments zero or multiple times, so the arguments should not have side effects.

These macros are tuned for their last argument being a constant.

INT_ADD_OVERFLOW (a, b)

Yield 1 if a + b would overflow, 0 otherwise. See above for restrictions.

INT_SUBTRACT_OVERFLOW (a, b)

Yield 1 if a - b would overflow, 0 otherwise. See above for restrictions.

INT_NEGATE_OVERFLOW (a)

Yields 1 if -a would overflow, 0 otherwise. See above for restrictions.

INT_MULTIPLY_OVERFLOW (a, b)

Yield 1 if a * b would overflow, 0 otherwise. See above for restrictions.

INT_DIVIDE_OVERFLOW (a, b)

Yield 1 if a / b would overflow, 0 otherwise. See above for restrictions. Division overflow can happen on two’s complement hosts when dividing the most negative integer by −1. This macro does not check for division by zero.

INT_REMAINDER_OVERFLOW (a, b)

Yield 1 if a % b would overflow, 0 otherwise. See above for restrictions. Remainder overflow can happen on two’s complement hosts when dividing the most negative integer by −1; although the mathematical result is always 0, in practice some implementations trap, so this counts as an overflow. This macro does not check for division by zero.

INT_LEFT_SHIFT_OVERFLOW (a, b)

Yield 1 if a << b would overflow, 0 otherwise. See above for restrictions. The C standard says that behavior is undefined for shifts unless 0≤b<w where w is a’s word width, and that when a is negative then a << b has undefined behavior, but this macro does not check these other restrictions.

Previous: , Up: Integer Properties   [Contents][Index]

18.7.7 Integer Range Overflow

These macros yield 1 if the corresponding C operators might not yield numerically correct answers due to arithmetic overflow, and 0 if if the operators do not overflow. They do not rely on undefined or implementation-defined behavior. They are integer constant expressions if their arguments are. Their implementations are simple and straightforward, but they are typically harder to use than the integer type overflow macros. See Integer Type Overflow.

Although the implementation of these macros is similar to that suggested in the SEI CERT C Secure Coding Standard, in its two sections “INT30-C. Ensure that unsigned integer operations do not wrap” and “INT32-C. Ensure that operations on signed integers do not result in overflow”, Gnulib’s implementation was derived independently of CERT’s suggestions.

Example usage: 

#include <intprops.h>
#include <limits.h>
#include <stdio.h>

void
print_product (long int a, long int b)
{
  if (INT_MULTIPLY_RANGE_OVERFLOW (a, b, LONG_MIN, LONG_MAX))
    printf ("multiply would overflow");
  else
    printf ("product is %ld", a * b);
}

/* Does the product of two ints always fit
   in a long int?  */
enum {
  INT_PRODUCTS_FIT_IN_LONG
    = ! (INT_MULTIPLY_RANGE_OVERFLOW
         ((long int) INT_MIN, (long int) INT_MIN,
          LONG_MIN, LONG_MAX))
};

These macros have the following restrictions:

  • Their arguments must be integer expressions.
  • They may evaluate their arguments zero or multiple times, so the arguments should not have side effects.
  • The arithmetic arguments (including the min and max arguments) must be of the same integer type after the usual arithmetic conversions, and the type must have minimum value min and maximum max. Unsigned values should use a zero min of the proper type, for example, (unsigned int) 0.

These macros are tuned for constant min and max. For commutative operations such as a + b, they are also tuned for constant b.

INT_ADD_RANGE_OVERFLOW (a, b, min, max)

Yield 1 if a + b would overflow in [min,max] integer arithmetic, 0 otherwise. See above for restrictions.

INT_SUBTRACT_RANGE_OVERFLOW (a, b, min, max)

Yield 1 if a - b would overflow in [min,max] integer arithmetic, 0 otherwise. See above for restrictions.

INT_NEGATE_RANGE_OVERFLOW (a, min, max)

Yield 1 if -a would overflow in [min,max] integer arithmetic, 0 otherwise. See above for restrictions.

INT_MULTIPLY_RANGE_OVERFLOW (a, b, min, max)

Yield 1 if a * b would overflow in [min,max] integer arithmetic, 0 otherwise. See above for restrictions.

INT_DIVIDE_RANGE_OVERFLOW (a, b, min, max)

Yield 1 if a / b would overflow in [min,max] integer arithmetic, 0 otherwise. See above for restrictions. Division overflow can happen on two’s complement hosts when dividing the most negative integer by −1. This macro does not check for division by zero.

INT_REMAINDER_RANGE_OVERFLOW (a, b, min, max)

Yield 1 if a % b would overflow in [min,max] integer arithmetic, 0 otherwise. See above for restrictions. Remainder overflow can happen on two’s complement hosts when dividing the most negative integer by −1; although the mathematical result is always 0, in practice some implementations trap, so this counts as an overflow. This macro does not check for division by zero.

INT_LEFT_SHIFT_RANGE_OVERFLOW (a, b, min, max)

Yield 1 if a << b would overflow in [min,max] integer arithmetic, 0 otherwise. See above for restrictions. Here, min and max are for a only, and b need not be of the same type as the other arguments. The C standard says that behavior is undefined for shifts unless 0≤b<w where w is a’s word width, and that when a is negative then a << b has undefined behavior, but this macro does not check these other restrictions.

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.8 Static inline functions

In order to mark functions as static inline in .c files, the only prerequisite you need is an AC_REQUIRE([AC_C_INLINE]). No Gnulib module is needed.

When marking functions as static inline in .h files, on the other hand, it is useful to avoid the following problem: When gcc or clang is not optimizing, it generates the same object code for every static inline function that is actually used in the current compilation unit, thus bloating the size of the resulting binary. (Code of static inline functions that are unused in the current compilation unit gets dropped; that is not an issue.) To avoid this problem, use the Gnulib module ‘inline’ and make the static inline function definition conditional on the value of the C macro HAVE_INLINE.

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.9 Extern inline functions

The extern-inline module supports the use of C99-style extern inline functions so that the code still runs on compilers that do not support this feature correctly.

C code ordinarily should not use inline. Typically it is better to let the compiler figure out whether to inline, as compilers are pretty good about optimization nowadays. In this sense, inline is like register, another keyword that is typically no longer needed.

Functions defined (not merely declared) in headers are an exception, as avoiding inline would commonly cause problems for these functions. Suppose aaa.h defines the function aaa_fun, and aaa.c, bbb.c and ccc.c all include aaa.h. If code is intended to portable to non-C99 compilers, aaa_fun cannot be declared with the C99 inline keyword. This problem cannot be worked around by making aaa_fun an ordinary function, as it would be defined three times with external linkage and the definitions would clash. Although aaa_fun could be a static function, with separate compilation if aaa_fun is not inlined its code will appear in the executable three times.

To avoid this code bloat, aaa.h can do this: 

/* aaa.h */
/* #include any other headers here */
#ifndef _GL_INLINE_HEADER_BEGIN
 #error "Please include config.h first."
#endif
_GL_INLINE_HEADER_BEGIN
#ifndef AAA_INLINE
# define AAA_INLINE _GL_INLINE
#endif
...
AAA_INLINE int
aaa_fun (int i)
{
  return i + 1;
}
...
_GL_INLINE_HEADER_END

and aaa.c can do this: 

/* aaa.c */
#define AAA_INLINE _GL_EXTERN_INLINE
#include <config.h>
#include <aaa.h>

whereas bbb.c and ccc.c can include aaa.h in the usual way. C99 compilers expand AAA_INLINE to C99-style inline usage, where aaa_fun is declared extern inline in aaa.c and plain inline in other modules. Non-C99 compilers that are compatible with GCC use GCC-specific syntax to accomplish the same ends. Other non-C99 compilers use static inline so they suffer from code bloat, but they are not mainline platforms and will die out eventually.

In this coding idiom, the compilation unit should define AAA_INLINE before including the aaa.h header that conditionally defines it. In the unusual and not-recommended case where config.h itself includes aaa.h, the compilation unit should define AAA_INLINE before including config.h, not merely before including aaa.h. Also, you need one AAA_INLINE-like macro per compilation unit, not one per header file. In other words, if the header file aaa.h defines functions defined in aaa-foo.c and aaa-bar.c, you need different macros AAA_FOO_INLINE and AAA_BAR_INLINE. Use AAA_FOO_INLINE for the functions defined in aaa-foo.c, and use AAA_BAR_INLINE for the functions defined in aaa-bar.c.

Functions defined in this way should not refer to identifiers with static linkage, as C99 through C23 prohibit this. Although a future C standard will likely relax this restriction, it is still an issue on many practical platforms.

_GL_INLINE is a portable alternative to C99 plain inline.

_GL_EXTERN_INLINE is a portable alternative to C99 extern inline.

Invoke _GL_INLINE_HEADER_BEGIN before all uses of _GL_INLINE in an include file. This suppresses some bogus warnings in GCC versions before 5.1. If an include file includes other files, it is better to invoke this macro after including the other files.

Invoke _GL_INLINE_HEADER_END after all uses of _GL_INLINE in an include file.

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.10 Handling closed standard file descriptors

Usually, when a program gets invoked, its file descriptors 0 (for standard input), 1 (for standard output), and 2 (for standard error) are open. But there are situations when some of these file descriptors are closed. These situations can arise when

  • The invoking process invokes close() on the file descriptor before exec, or
  • The invoking process invokes posix_spawn_file_actions_addclose() for the file descriptor before posix_spawn or posix_spawnp, or
  • The invoking process is a Bourne shell, and the shell script uses the POSIX syntax for closing the file descriptor: <&- for closing standard input, >&- for closing standard output, or 2>&- for closing standard error.

When a closed file descriptor is accessed through a system call, such as fcntl(), fstat(), read(), or write(), the system calls fails with error EBADF ("Bad file descriptor").

When a new file descriptor is allocated, the operating system chooses the smallest non-negative integer that does not yet correspond to an open file descriptor. So, when a given fd (0, 1, or 2) is closed, opening a new file descriptor may assign the new file descriptor to this fd. This can have unintended effects, because now standard input/output/error of your process is referring to a file that was not meant to be used in that role.

This situation is a security risk because the behaviour of the program in this situation was surely never tested, therefore anything can happen then – from overwriting precious files of the user to endless loops.

To deal with this situation, you first need to determine whether your program is affected by the problem.

  • Does your program invoke functions that allocate new file descriptors? These are the system calls
    • open(), openat(), creat()
    • dup()
    • fopen(), freopen()
    • pipe(), pipe2(), popen()
    • opendir()
    • tmpfile(), mkstemp(), mkstemps(), mkostemp(), mkostemps()

    Note that you also have to consider the libraries that your program uses.

  • If your program may open two or more file descriptors or FILE streams for reading at the same time, and some of them may reference standard input, your program is affected.
  • If your program may open two or more file descriptors or FILE streams for writing at the same time, and some of them may reference standard output or standard error, your program is affected.
  • If your program does not open new file descriptors or FILE streams, it is not affected.
  • If your program opens only one new file descriptor or FILE stream at a time, it is not affected. This is often the case for programs that are structured in simple phases: first a phase where input is read from a file into memory, then a phase of processing in memory, finally a phase where the result is written to a file.
  • If your program opens only two new file descriptors or FILE streams at a time, out of which one is for reading and the one is for writing, it is not affected. This is because if the first file descriptor is allocated and the second file descriptor is picked as 0, 1, or 2, and both happen to be the same, writing to the one opened in O_RDONLY mode will produce an error EBADF, as desired.

If your program is affected, what is the mitigation?

Some operating systems install open file descriptors in place of the closed ones, either in the exec system call or during program startup. When such a file descriptor is accessed through a system call, it behaves like an open file descriptor opened for the “wrong” direction: the system calls fcntl() and fstat() succeed, whereas read() from fd 0 and write() to fd 1 or 2 fail with error EBADF ("Bad file descriptor"). The important point here is that when your program allocates a new file descriptor, it will have a value greater than 2.

This mitigation is enabled on HP-UX, for all programs, and on glibc, FreeBSD, NetBSD, OpenBSD, but only for setuid or setgid programs. Since it is operating system dependent, it is not a complete mitigation.

For a complete mitigation, Gnulib provides two alternative sets of modules:

  • The xstdopen module.
  • The *-safer modules: fcntl-safer, openat-safer, unistd-safer, fopen-safer, freopen-safer, pipe2-safer, popen-safer, dirent-safer, tmpfile-safer, stdlib-safer.

The approach with the xstdopen module is simple, but it adds three system calls to program startup. Whereas the approach with the *-safer modules is more complicated and error-prone, and does not fix the problem if system library functions call one of the affected functions, but adds no overhead (no additional system calls) in the normal case.

To use the approach with the xstdopen module:

  1. Import the module xstdopen from Gnulib.
  2. In the compilation unit that contains the main function, include "xstdopen.h".
  3. In the main function, near the beginning, namely right after the i18n related initializations (setlocale, bindtextdomain, textdomain invocations, if any) and the closeout initialization (if any), insert the invocation: 
    /* Ensure that stdin, stdout, stderr are open.  */
xstdopen ();

To use the approach with the *-safer modules:

  1. Import the relevant modules from Gnulib.
  2. In the compilation units that contain these function calls, include the replacement header file.

Do so according to this table:

FunctionModuleHeader file
open()fcntl-safer"fcntl--.h"
openat()openat-safer"fcntl--.h"
creat()fcntl-safer"fcntl--.h"
dup()unistd-safer"unistd--.h"
fopen()fopen-safer"stdio--.h"
freopen()freopen-safer"stdio--.h"
pipe()unistd-safer"unistd--.h"
pipe2()pipe2-safer"unistd--.h"
popen()popen-safer"stdio--.h"
opendir()dirent-safer"dirent--.h"
tmpfile()tmpfile-safer"stdio--.h"
mkstemp()stdlib-safer"stdlib--.h"
mkstemps()stdlib-safer"stdlib--.h"
mkostemp()stdlib-safer"stdlib--.h"
mkostemps()stdlib-safer"stdlib--.h"

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.11 Handling strings with NUL characters

Strings in C are usually represented by a character sequence with a terminating NUL character. A ‘char *’, pointer to the first byte of this character sequence, is what gets passed around as function argument or return value.

The major restriction of this string representation is that it cannot handle strings that contain NUL characters: such strings will appear shorter than they were meant to be. In most application areas, this is not a problem, and the char * type is well usable.

A second problem of this string representation is that taking a substring is not cheap: it either requires a memory allocation or a destructive modification of the string. The former has a runtime cost; the latter complicates the logic of the program. This matters for application areas that analyze text, such as parsers.

In areas where strings with embedded NUL characters need to be handled or where taking substrings is a recurrent operation, the common approach is to use a char *ptr pointer variable together with a size_t nbytes variable (or an idx_t nbytes variable, if you want to avoid problems due to integer overflow). This works fine in code that constructs or manipulates strings with embedded NUL characters. But when it comes to storing them, for example in an array or as key or value of a hash table, one needs a type that combines these two fields.

The Gnulib modules string-desc, xstring-desc, and string-desc-quotearg provide such a type. We call it a “string descriptor” and name it string_desc_t.

The type string_desc_t is a struct that contains a pointer to the first byte and the number of bytes of the memory region that make up the string. An additional terminating NUL byte, that may be present in memory, is not included in this byte count. This type implements the same concept as std::string_view in C++, or the String type in Java.

string_desc_t is a string descriptor to a string that cannot be written to. There is also a type rw_string_desc_t, that is a descriptor for a writable string. rw_string_desc_t compares to string_desc_t, like the pointer type ‘char *’ compares to the pointer type ‘const char *’.

A string_desc_t or rw_string_desc_t can be passed to a function as an argument, or can be the return value of a function. This is type-safe: If, by mistake, a programmer passes a string_desc_t to a function that expects a char * argument, or vice versa, or assigns a string_desc_t value to a variable of type char *, or vice versa, the compiler will report an error.

Unfortunately, string_desc_t and rw_string_desc_t being different types, there is no implicit conversion from rw_string_desc_t to string_desc_t. In places where such a conversion is desired, the (inline) function sd_readonly needs to be called.

Functions related to string descriptors are provided:

  • Side-effect-free operations in "string-desc.h",
  • Memory-allocating operations in "string-desc.h",
  • Memory-allocating operations with out-of-memory checking in "xstring-desc.h",
  • Operations with side effects in "string-desc.h".

For outputting a string descriptor, the *printf family of functions cannot be used directly. A format string directive such as "%.*s" would not work:

  • it would stop the output at the first encountered NUL character,
  • it would require to cast the number of bytes to int, and thus would not work for strings longer than INT_MAX bytes.

Therefore Gnulib offers

  • a function sd_fwrite that outputs a string descriptor to a FILE stream,
  • a function sd_write that outputs a string descriptor to a file descriptor,
  • and for those applications where the NUL characters should become visible as ‘\0’, a family of quotearg based functions, that allow to specify the escaping rules in detail.

The functionality is thus split across three modules as follows:

  • The module string-desc, under LGPL, defines the type and elementary functions.
  • The module xstring-desc, under GPL, defines the memory-allocating functions with out-of-memory checking.
  • The module string-desc-quotearg, under GPL, defines the quotearg based functions.

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.12 Container data types

Gnulib provides several generic container data types. They can be used to organize collections of application-defined objects.

Next: , Up: Container data types   [Contents][Index]

18.12.1 Ordinary container data types

Data typeDetailsModuleMain include fileInclude file for operations with out-of-memory checking
Sequential listCan contain any number of objects in any given order. Duplicates are allowed, but can optionally be forbidden.list"gl_list.h""gl_xlist.h"
SetCan contain any number of objects; the order does not matter. Duplicates (in the sense of the comparator) are forbidden.set"gl_set.h""gl_xset.h"
Ordered setCan contain any number of objects in the order of a given comparator function. Duplicates (in the sense of the comparator) are forbidden.oset"gl_oset.h""gl_xoset.h"
MapCan contain any number of (key, value) pairs, where keys and values are objects; there are no (key, value1) and (key, value2) pairs with the same key (in the sense of a given comparator function).map"gl_map.h""gl_xmap.h"
Ordered mapCan contain any number of (key, value) pairs, where keys and values are objects; the (key, value) pairs are ordered by the key, in the order of a given comparator function; there are no (key, value1) and (key, value2) pairs with the same key (in the sense of the comparator function).omap"gl_omap.h""gl_xomap.h"

Operations without out-of-memory checking (suitable for use in libraries) are declared in the “main include file”. Whereas operations with out-of-memory checking (suitable only in programs) are declared in the “include file for operations with out-of-memory checking”.

For each of the data types, several implementations are available, with different performance profiles with respect to the available operations. This enables you to start with the simplest implementation (ARRAY) initially, and switch to a more suitable implementation after profiling your application. The implementation of each container instance is specified in a single place only: in the invocation of the function gl_*_create_empty that creates the instance.

18.12.1.1 Sequential lists

The implementations and the guaranteed average performance for the operations for the “sequential list” data type are:

OperationARRAYCARRAYLINKEDTREELINKEDHASH with duplicatesLINKEDHASH without duplicatesTREEHASH with duplicatesTREEHASH without duplicates
gl_list_sizeO(1)O(1)O(1)O(1)O(1)O(1)O(1)O(1)
gl_list_node_valueO(1)O(1)O(1)O(1)O(1)O(1)O(1)O(1)
gl_list_node_set_valueO(1)O(1)O(1)O(1)O(1)O(1)O((log n)2)O(1)
gl_list_next_nodeO(1)O(1)O(1)O(log n)O(1)O(1)O(log n)O(log n)
gl_list_previous_nodeO(1)O(1)O(1)O(log n)O(1)O(1)O(log n)O(log n)
gl_list_first_nodeO(1)O(1)O(1)O(log n)O(1)O(1)O(log n)O(log n)
gl_list_last_nodeO(1)O(1)O(1)O(log n)O(1)O(1)O(log n)O(log n)
gl_list_get_atO(1)O(1)O(n)O(log n)O(n)O(n)O(log n)O(log n)
gl_list_get_firstO(1)O(1)O(1)O(log n)O(1)O(1)O(log n)O(log n)
gl_list_get_lastO(1)O(1)O(1)O(log n)O(1)O(1)O(log n)O(log n)
gl_list_set_atO(1)O(1)O(n)O(log n)O(n)O(n)O((log n)2)O(log n)
gl_list_set_firstO(1)O(1)O(1)O(log n)O(n)O(1)O((log n)2)O(log n)
gl_list_set_lastO(1)O(1)O(1)O(log n)O(n)O(1)O((log n)2)O(log n)
gl_list_searchO(n)O(n)O(n)O(n)O(n)O(1)O(log n)O(1)
gl_list_search_fromO(n)O(n)O(n)O(n)O(n)O(1)O((log n)2)O(log n)
gl_list_search_from_toO(n)O(n)O(n)O(n)O(n)O(1)O((log n)2)O(log n)
gl_list_indexofO(n)O(n)O(n)O(n)O(n)O(n)O(log n)O(log n)
gl_list_indexof_fromO(n)O(n)O(n)O(n)O(n)O(n)O((log n)2)O(log n)
gl_list_indexof_from_toO(n)O(n)O(n)O(n)O(n)O(n)O((log n)2)O(log n)
gl_list_add_firstO(n)O(1)O(1)O(log n)O(1)O(1)O((log n)2)O(log n)
gl_list_add_lastO(1)O(1)O(1)O(log n)O(1)O(1)O((log n)2)O(log n)
gl_list_add_beforeO(n)O(n)O(1)O(log n)O(1)O(1)O((log n)2)O(log n)
gl_list_add_afterO(n)O(n)O(1)O(log n)O(1)O(1)O((log n)2)O(log n)
gl_list_add_atO(n)O(n)O(n)O(log n)O(n)O(n)O((log n)2)O(log n)
gl_list_remove_nodeO(n)O(n)O(1)O(log n)O(n)O(1)O((log n)2)O(log n)
gl_list_remove_atO(n)O(n)O(n)O(log n)O(n)O(n)O((log n)2)O(log n)
gl_list_remove_firstO(n)O(1)O(1)O(log n)O(n)O(1)O((log n)2)O(log n)
gl_list_remove_lastO(1)O(1)O(1)O(log n)O(n)O(1)O((log n)2)O(log n)
gl_list_removeO(n)O(n)O(n)O(n)O(n)O(1)O((log n)2)O(log n)
gl_list_iteratorO(1)O(1)O(1)O(log n)O(1)O(1)O(log n)O(log n)
gl_list_iterator_from_toO(1)O(1)O(n)O(log n)O(n)O(n)O(log n)O(log n)
gl_list_iterator_nextO(1)O(1)O(1)O(log n)O(1)O(1)O(log n)O(log n)
gl_sortedlist_searchO(log n)O(log n)O(n)O(log n)O(n)O(n)O(log n)O(log n)
gl_sortedlist_search_fromO(log n)O(log n)O(n)O(log n)O(n)O(n)O(log n)O(log n)
gl_sortedlist_indexofO(log n)O(log n)O(n)O(log n)O(n)O(n)O(log n)O(log n)
gl_sortedlist_indexof_fromO(log n)O(log n)O(n)O(log n)O(n)O(n)O(log n)O(log n)
gl_sortedlist_addO(n)O(n)O(n)O(log n)O(n)O(n)O((log n)2)O(log n)
gl_sortedlist_removeO(n)O(n)O(n)O(log n)O(n)O(n)O((log n)2)O(log n)

The Gnulib modules for sequential lists are:

ImplementationModules
Abstractlist, xlist
ARRAYarray-list
CARRAYcarray-list
LINKEDlinked-list
TREEavltree-list, rbtree-list
LINKEDHASHlinkedhash-list
TREEHASHavltreehash-list, rbtreehash-list
Portion of a listsublist, xsublist

18.12.1.2 Sets

The implementations and the guaranteed average performance for the operations for the “set” data type are:

OperationARRAYLINKEDHASH, HASH
gl_set_sizeO(1)O(1)
gl_set_addO(n)O(1)
gl_set_removeO(n)O(1)
gl_set_searchO(n)O(1)
gl_set_iteratorO(1)O(1)
gl_set_iterator_nextO(1)O(1)

The Gnulib modules for sets are:

ImplementationModules
Abstractset, xset
ARRAYarray-set
LINKEDHASHlinkedhash-set
HASHhash-set

18.12.1.3 Ordered sets

The implementations and the guaranteed average performance for the operations for the “ordered set” data type are:

OperationARRAYTREE
gl_oset_sizeO(1)O(1)
gl_oset_addO(n)O(log n)
gl_oset_removeO(n)O(log n)
gl_oset_searchO(log n)O(log n)
gl_oset_search_atleastO(log n)O(log n)
gl_oset_iteratorO(1)O(log n)
gl_oset_iterator_nextO(1)O(log n)

The Gnulib modules for ordered sets are:

ImplementationModules
Abstractoset, xoset
ARRAYarray-oset
TREEavltree-oset, rbtree-oset

18.12.1.4 Maps

The implementations and the guaranteed average performance for the operations for the “map” data type are:

OperationARRAYLINKEDHASH, HASH
gl_map_sizeO(1)O(1)
gl_map_getO(n)O(1)
gl_map_putO(n)O(1)
gl_map_removeO(n)O(1)
gl_map_searchO(n)O(1)
gl_map_iteratorO(1)O(1)
gl_map_iterator_nextO(1)O(1)

The Gnulib modules for maps are:

ImplementationModules
Abstractmap, xmap
ARRAYarray-map
LINKEDHASHlinkedhash-map
HASHhash-map

18.12.1.5 Ordered maps

The implementations and the guaranteed average performance for the operations for the “ordered map” data type are:

OperationARRAYTREE
gl_omap_sizeO(1)O(1)
gl_omap_getO(log n)O(log n)
gl_omap_putO(n)O(log n)
gl_omap_removeO(n)O(log n)
gl_omap_searchO(log n)O(log n)
gl_omap_search_atleastO(log n)O(log n)
gl_omap_iteratorO(1)O(log n)
gl_omap_iterator_nextO(1)O(log n)

The Gnulib modules for ordered maps are:

ImplementationModules
Abstractomap, xomap
ARRAYarray-omap
TREEavltree-omap, rbtree-omap

18.12.1.6 C++ classes for container data types

For C++, Gnulib provides a C++ template class for each of these container data types.

Data typeC++ classModuleInclude file
Sequential listgl_Listlist-c++"gl_list.hh"
Setgl_Setset-c++"gl_set.hh"
Ordered setgl_OSetoset-c++"gl_oset.hh"
Mapgl_Mapmap-c++"gl_map.hh"
Ordered mapgl_OMapomap-c++"gl_omap.hh"

Previous: , Up: Container data types   [Contents][Index]

18.12.2 Specialized container data types

The hamt module implements the hash array mapped trie (HAMT) data structure. This is a data structure that contains (key, value) pairs. Lookup of a (key, value) pair given the key is on average an O(1) operation, assuming a good hash function for the keys is employed.

The HAMT data structure is useful when you want modifications (additions of pairs, removal, value changes) to be visible only to some part of your program, whereas other parts of the program continue to use the unmodified HAMT. The HAMT makes this possible in a space-efficient manner: the modified and the unmodified HAMT share most of their allocated memory. It is also time-efficient: Every such modification is O(1) on average, again assuming a good hash function for the keys.

A HAMT can be used whenever an ordinary hash table would be used. It does however, provide non-destructive updating operations without the need to copy the whole container. On the other hand, a hash table is simpler so that its performance may be better when non-destructive update operations are not needed.

For example, a HAMT can be used to model the dynamic environment in a LISP interpreter. Updating a value in the dynamic environment of one continuation frame would not modify values in earlier frames.

To use the module, include hamt.h in your code. The public interface is documented in that header file. You have to provide a hash function and an equivalence relation, which defines key equality. The module includes a test file test-hamt.c, which demonstrates how the API can be used.

In the current implementation, each inner node of the HAMT can store up to 32 = 2^5 entries and subtries. Whenever a collision between the initial bits of the hash values of two entries would happen, the next 5 bits of the hash values are examined and the two entries pushed down one level in the trie.

HAMTs have the same average access times as hash tables but grow and shrink dynamically, so they use memory more economically and do not have to be periodically resized.

They were described and analyzed in Phil Bagwell (2000). Ideal Hash Trees (Report). Infoscience Department, École Polytechnique Fédérale de Lausanne.

The persistence aspect of the HAMT data structure, which means that each updating operation (like inserting, replacing, or removing an entry) returns a new HAMT while leaving the original one intact, is achieved through structure sharing, which is even safe in the presence of multiple threads when the used C compiler supports atomics.

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.13 Modernized printf

The *zprintf family of functions is a modernized form of the *printf family of functions.

The problem

The *printf functions have a return type ‘int’ and therefore can only produce results that are up to (2 GiB - 1 byte) long.

The problem with this is not so much that it is an arbitrary limitation (that persists even in processes that have, say, 50 GiB of RAM available). The bigger problem is that in reliable programs, it requires handling of an error code EOVERFLOW that indicates a result whose size would be 2 GiB or larger.

How does a reliable program do error handling of *printf function calls? For output to strings and file descriptors (such as sprintf and dprintf), there is no other way than to check each such call.

For output to FILE streams (such as fprintf), beginners are tempted to ignore the return value of each call and instead check ferror (stream) at the end. The problem with this approach is that at the moment the error is detected, incorrect output has already been sent onto the stream. So, in this case as well, the reliable approach is to check each such call.

The simple format strings that most programs use in 99% of the places, namely with no wide string or wide character arguments, nor with widths passed as int argument, can only fail with two possible error codes:

  • ENOMEM, when the result would be too large to allocate in the process’ memory.
  • EOVERFLOW, when the result is 2 GiB or larger but still allocatable.

Many GNU programs use “checking” wrappers (functions xvasprintf, etc.) that check for ENOMEM and call xalloc_die, thus aborting the program in that case. The problem is that EOVERFLOW is not handled, even with such wrappers.

Should EOVERFLOW be handled like ENOMEM, by aborting the program? No, as mentioned above, that would be an arbitrary limitation, which the GNU Coding Standards urge us to avoid.

The solution

The *zprintf functions are like the *printf functions, except that the return type is

  • ptrdiff_t instead of int, for output to strings,
  • off64_t (which is always equivalent to int64_t) instead of int, for output to file streams and file descriptors.

Thus, for these functions, EOVERFLOW cannot occur (except for format strings which take widths as argument, which we have excluded above), and the “checking” wrappers (functions xvasprintf, etc.) are thus sufficient for ensuring an error-free result.

Note: In 64-bit processes, ptrdiff_t is 64 bits wide, i.e. equivalent to int64_t. In 32-bit processes, ptrdiff_t is only 32 bits wide, but since in these environments, memory regions of 2 GiB or larger cannot be allocated anyway (malloc would fail with ENOMEM), this type is sufficient.

The following Gnulib functions and modules exist:

Original functionModernized functionModules
sprintfszprintfszprintf, szprintf-posix, szprintf-gnu
vsprintfvszprintfvszprintf, vszprintf-posix, vszprintf-gnu
snprintfsnzprintfsnzprintf, snzprintf-posix, snzprintf-gnu
vsnprintfvsnzprintfvsnzprintf, vsnzprintf-posix, vsnzprintf-gnu
asprintfaszprintfvaszprintf, vaszprintf-posix, vaszprintf-gnu
vasprintfvaszprintfvaszprintf, vaszprintf-posix, vaszprintf-gnu
c_snprintfc_snzprintfc-snzprintf, c-snzprintf-gnu
c_vsnprintfc_vsnzprintfc-vsnzprintf, c-vsnzprintf-gnu
c_asprintfc_aszprintfc-vaszprintf, c-vaszprintf-gnu
c_vasprintfc_vaszprintfc-vaszprintf, c-vaszprintf-gnu
fprintffzprintffzprintf, fzprintf-posix, fzprintf-gnu
vfprintfvfzprintfvfzprintf, vfzprintf-posix, vfzprintf-gnu
printfzprintfzprintf, zprintf-posix, zprintf-gnu
vprintfvzprintfvzprintf, vzprintf-posix, vzprintf-gnu
dprintfdzprintfdzprintf, dzprintf-posix, dzprintf-gnu
vdprintfvdzprintfvdzprintf, vdzprintf-posix, vdzprintf-gnu
obstack_printfobstack_zprintfobstack-zprintf, obstack-zprintf-posix, obstack-zprintf-gnu
obstack_vprintfobstack_vzprintfobstack-zprintf, obstack-zprintf-posix, obstack-zprintf-gnu

The following functions use the *zprintf functions under the hood and thus don’t need a *zprintf variant:

FunctionModules
xasprintfxvasprintf, xvasprintf-posix, xvasprintf-gnu
xvasprintfxvasprintf, xvasprintf-posix, xvasprintf-gnu
c_xasprintfc-xvasprintf
c_xvasprintfc-xvasprintf
xprintfxprintf, xprintf-posix, xprintf-gnu
xvprintfxprintf, xprintf-posix, xprintf-gnu
xfprintfxprintf, xprintf-posix, xprintf-gnu
xvfprintfxprintf, xprintf-posix, xprintf-gnu

Note: Even with the *zprintf functions, you need to be prepared to handle specific error codes when you use non-simple format strings:

  • EILSEQ when the format string takes wide strings or wide characters as arguments,
  • EOVERFLOW when the format string takes a width as argument and you cannot ensure that its value is in the range 0...INT_MAX.

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.14 Advanced functions on FILE streams

Gnulib provides a few functions that operate on FILE * streams and that go beyond what ISO C and POSIX specify.

Each such function is provided in a Gnulib module of the same name.

When Gnulib implemented them in 2007, some people considered them “unportable”, because they required digging in undocumented internals of the FILE structure. But Gnulib made them portable, by providing implementations for all platforms, from glibc to native Windows, and from Minix to QNX. Nowadays, new platforms already implement them in their libc; this has been seen for the Android libc and musl libc.

The stream argument of these functions must not be wide-character oriented. But this is not an actual restriction, since no programs use wide-character orientation on FILE streams anyway: no one uses the fwide function.

Next: , Up: Advanced functions on FILE streams   [Contents][Index]

18.14.1 Determining the state of a FILE stream

Gnulib modules: freadable, fwritable, freading, fwriting

The freadable function returns true if the given stream supports reading, false if it supports only writing, i.e. if it was opened write-only or append-only.

The fwritable function returns true if the given stream supports writing, false if it supports only reading.

The freading function returns true if the given stream is opened read-only, or if the last operation on the stream was a read operation.

The fwriting function returns true if the given stream is opened write-only or append-only, or if the last operation on the stream was a write operation.

freading and fwriting will never both be true on the same stream at the same time. If the stream supports both reads and writes, then

  • both freading and fwriting might be false when the stream is first opened, after read encounters EOF, or after fflush,
  • freading might be false or true and fwriting might be false after repositioning (such as fseek, fsetpos, or rewind),

depending on the underlying implementation.

Next: , Previous: , Up: Advanced functions on FILE streams   [Contents][Index]

18.14.2 Setting an error in a FILE stream

A FILE * stream has an error indicator, that can be tested through the ferror function and cleared through the clearerr function. The error indicator is set when an I/O operation on the stream fails. But ISO C and POSIX don’t provide a way to set the error indicator!

The fseterr function sets the error indicator in the given stream.

Next: , Previous: , Up: Advanced functions on FILE streams   [Contents][Index]

18.14.3 Dropping the contents of the buffers of a FILE stream

The fpurge function drops the contents of the input and output buffers of the given FILE * stream:

  • It discards the contents of the output buffer, if the stream is currently writing. That is the opposite of what the fflush function does.
  • It discards the contents of the input buffer, if the stream is currently reading. That is the same as what the fflush function does.

Next: , Previous: , Up: Advanced functions on FILE streams   [Contents][Index]

18.14.4 Accessing the write buffer of a FILE stream

The following two functions provide information about the output buffer of a FILE * stream.

The fpending function returns the number of pending (a.k.a. buffered, unflushed) bytes in the given stream.

The fbufmode function returns the buffering mode of the given stream:

Resultmeans
_IONBFunbuffered
_IOLBFline buffered
_IOFBFfully buffered

Note that on some platforms, it is impossible to distinguish _IOFBF and _IOLBF.

Previous: , Up: Advanced functions on FILE streams   [Contents][Index]

18.14.5 Accessing the read buffer of a FILE stream

The following functions allow code to scan the contents of the input buffer of a FILE * stream, without first copying it into a separate memory area via fread.

The function freadahead returns the number of bytes waiting in the input buffer of the given stream. This includes both the bytes that have been read from the underlying input source and the bytes that have been pushed back through ungetc.

A function call freadptr (stream, &size) returns a pointer to the input buffer of the given stream, or NULL. If the returned pointer is non-NULL, size is set to the (positive) size of the input buffer. If the returned pointer is NULL, you should use getc (stream), fgetc (stream), or fread (..., stream) to access the input from stream.

A function call freadseek (stream, offset) is the same as fseek (stream, offset, SEEK_CUR), except that the latter does not work on non-seekable input streams (such as pipes).

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.15 libunistring

GNU libunistring provides functions for manipulating Unicode strings and for manipulating C strings according to the Unicode standard.

It consists of the following parts:

<unistr.h>elementary string functions
<uniconv.h>conversion from/to legacy encodings
<unistdio.h>formatted output to strings
<uniname.h>character names
<unictype.h>character classification and properties
<uniwidth.h>string width when using nonproportional fonts
<unigbrk.h>grapheme cluster breaks
<uniwbrk.h>word breaks
<unilbrk.h>line breaking algorithm
<uninorm.h>normalization (composition and decomposition)
<unicase.h>case folding

Nearly all of the source code of GNU libunistring resides in Gnulib.

Next: , Up: libunistring   [Contents][Index]

18.15.1 How to use libunistring

There are three ways to use GNU libunistring:

  • You can declare GNU libunistring as a prerequisite of your package and then, at build time, link with the installed libunistring. To achieve this, use the Gnulib module libunistring.
  • You can include the source code of specific libunistring modules in your package, through the usual Gnulib mechanism. Then, there is no prerequisite.
  • A combination of both: You can declare GNU libunistring as an optional prerequisite of your package and include the source code of specific libunistring modules in your package. At configure time, when the user has specified the configure option --with-included-libunistring, the included modules will be used and the package will not link against an installed libunistring. Otherwise, the package will link against an installed libunistring if found, and only those modules will be built that are not contained or that are too old in the found libunistring. To achieve this, request from Gnulib the specific modules and the Gnulib module libunistring-optional.

Previous: , Up: libunistring   [Contents][Index]

18.15.2 The libunistring modules

Every function or variable that is part of the GNU libunistring API is available through a specific Gnulib module. For the documentation, refer to the GNU libunistring documentation.

Next: , Up: The libunistring modules   [Contents][Index]

18.15.2.1 Declarations in <unitypes.h>

The <unitypes.h> header file is provided by the module unitypes-h.

Next: , Previous: , Up: The libunistring modules   [Contents][Index]

18.15.2.2 Declarations in <unistr.h>

FunctionModule
u8_checkunistr/u8-check
u16_checkunistr/u16-check
u32_checkunistr/u32-check
u8_to_u16unistr/u8-to-u16
u8_to_u32unistr/u8-to-u32
u16_to_u8unistr/u16-to-u8
u16_to_u32unistr/u16-to-u32
u32_to_u8unistr/u32-to-u8
u32_to_u16unistr/u32-to-u16
u8_mblenunistr/u8-mblen
u16_mblenunistr/u16-mblen
u32_mblenunistr/u32-mblen
u8_mbtoucunistr/u8-mbtouc
u16_mbtoucunistr/u16-mbtouc
u32_mbtoucunistr/u32-mbtouc
u8_mbtouc_unsafeunistr/u8-mbtouc-unsafe
u16_mbtouc_unsafeunistr/u16-mbtouc-unsafe
u32_mbtouc_unsafeunistr/u32-mbtouc-unsafe
u8_mbtoucrunistr/u8-mbtoucr
u16_mbtoucrunistr/u16-mbtoucr
u32_mbtoucrunistr/u32-mbtoucr
u8_uctombunistr/u8-uctomb
u16_uctombunistr/u16-uctomb
u32_uctombunistr/u32-uctomb
u8_cpyunistr/u8-cpy
u16_cpyunistr/u16-cpy
u32_cpyunistr/u32-cpy
u8_pcpyunistr/u8-pcpy
u16_pcpyunistr/u16-pcpy
u32_pcpyunistr/u32-pcpy
u8_moveunistr/u8-move
u16_moveunistr/u16-move
u32_moveunistr/u32-move
u8_setunistr/u8-set
u16_setunistr/u16-set
u32_setunistr/u32-set
u8_cmpunistr/u8-cmp
u16_cmpunistr/u16-cmp
u32_cmpunistr/u32-cmp
u8_cmp2unistr/u8-cmp2
u16_cmp2unistr/u16-cmp2
u32_cmp2unistr/u32-cmp2
u8_chrunistr/u8-chr
u16_chrunistr/u16-chr
u32_chrunistr/u32-chr
u8_mbsnlenunistr/u8-mbsnlen
u16_mbsnlenunistr/u16-mbsnlen
u32_mbsnlenunistr/u32-mbsnlen
u8_cpy_allocunistr/u8-cpy-alloc
u16_cpy_allocunistr/u16-cpy-alloc
u32_cpy_allocunistr/u32-cpy-alloc
u8_strmblenunistr/u8-strmblen
u16_strmblenunistr/u16-strmblen
u32_strmblenunistr/u32-strmblen
u8_strmbtoucunistr/u8-strmbtouc
u16_strmbtoucunistr/u16-strmbtouc
u32_strmbtoucunistr/u32-strmbtouc
u8_nextunistr/u8-next
u16_nextunistr/u16-next
u32_nextunistr/u32-next
u8_prevunistr/u8-prev
u16_prevunistr/u16-prev
u32_prevunistr/u32-prev
u8_strlenunistr/u8-strlen
u16_strlenunistr/u16-strlen
u32_strlenunistr/u32-strlen
u8_strnlenunistr/u8-strnlen
u16_strnlenunistr/u16-strnlen
u32_strnlenunistr/u32-strnlen
u8_strcpyunistr/u8-strcpy
u16_strcpyunistr/u16-strcpy
u32_strcpyunistr/u32-strcpy
u8_stpcpyunistr/u8-stpcpy
u16_stpcpyunistr/u16-stpcpy
u32_stpcpyunistr/u32-stpcpy
u8_strncpyunistr/u8-strncpy
u16_strncpyunistr/u16-strncpy
u32_strncpyunistr/u32-strncpy
u8_stpncpyunistr/u8-stpncpy
u16_stpncpyunistr/u16-stpncpy
u32_stpncpyunistr/u32-stpncpy
u8_strcatunistr/u8-strcat
u16_strcatunistr/u16-strcat
u32_strcatunistr/u32-strcat
u8_strncatunistr/u8-strncat
u16_strncatunistr/u16-strncat
u32_strncatunistr/u32-strncat
u8_strcmpunistr/u8-strcmp
u16_strcmpunistr/u16-strcmp
u32_strcmpunistr/u32-strcmp
u8_strcollunistr/u8-strcoll
u16_strcollunistr/u16-strcoll
u32_strcollunistr/u32-strcoll
u8_strncmpunistr/u8-strncmp
u16_strncmpunistr/u16-strncmp
u32_strncmpunistr/u32-strncmp
u8_strdupunistr/u8-strdup
u16_strdupunistr/u16-strdup
u32_strdupunistr/u32-strdup
u8_strchrunistr/u8-strchr
u16_strchrunistr/u16-strchr
u32_strchrunistr/u32-strchr
u8_strrchrunistr/u8-strrchr
u16_strrchrunistr/u16-strrchr
u32_strrchrunistr/u32-strrchr
u8_strcspnunistr/u8-strcspn
u16_strcspnunistr/u16-strcspn
u32_strcspnunistr/u32-strcspn
u8_strspnunistr/u8-strspn
u16_strspnunistr/u16-strspn
u32_strspnunistr/u32-strspn
u8_strpbrkunistr/u8-strpbrk
u16_strpbrkunistr/u16-strpbrk
u32_strpbrkunistr/u32-strpbrk
u8_strstrunistr/u8-strstr
u16_strstrunistr/u16-strstr
u32_strstrunistr/u32-strstr
u8_startswithunistr/u8-startswith
u16_startswithunistr/u16-startswith
u32_startswithunistr/u32-startswith
u8_endswithunistr/u8-endswith
u16_endswithunistr/u16-endswith
u32_endswithunistr/u32-endswith
u8_strtokunistr/u8-strtok
u16_strtokunistr/u16-strtok
u32_strtokunistr/u32-strtok

Next: , Previous: , Up: The libunistring modules   [Contents][Index]

18.15.2.3 Declarations in <uniconv.h>

FunctionModule
locale_charsetlocalcharset
u8_conv_from_encodinguniconv/u8-conv-from-enc
u16_conv_from_encodinguniconv/u16-conv-from-enc
u32_conv_from_encodinguniconv/u32-conv-from-enc
u8_conv_to_encodinguniconv/u8-conv-to-enc
u16_conv_to_encodinguniconv/u16-conv-to-enc
u32_conv_to_encodinguniconv/u32-conv-to-enc
u8_strconv_from_encodinguniconv/u8-strconv-from-enc
u16_strconv_from_encodinguniconv/u16-strconv-from-enc
u32_strconv_from_encodinguniconv/u32-strconv-from-enc
u8_strconv_to_encodinguniconv/u8-strconv-to-enc
u16_strconv_to_encodinguniconv/u16-strconv-to-enc
u32_strconv_to_encodinguniconv/u32-strconv-to-enc
u8_strconv_from_localeuniconv/u8-strconv-from-locale
u16_strconv_from_localeuniconv/u16-strconv-from-locale
u32_strconv_from_localeuniconv/u32-strconv-from-locale
u8_strconv_to_localeuniconv/u8-strconv-to-locale
u16_strconv_to_localeuniconv/u16-strconv-to-locale
u32_strconv_to_localeuniconv/u32-strconv-to-locale

Next: , Previous: , Up: The libunistring modules   [Contents][Index]

18.15.2.4 Declarations in <unistdio.h>

FunctionModule
ulc_sprintfunistdio/ulc-sprintf
ulc_snprintfunistdio/ulc-snprintf
ulc_asprintfunistdio/ulc-asprintf
ulc_asnprintfunistdio/ulc-asnprintf
ulc_vsprintfunistdio/ulc-vsprintf
ulc_vsnprintfunistdio/ulc-vsnprintf
ulc_vasprintfunistdio/ulc-vasprintf
ulc_vasnprintfunistdio/ulc-vasnprintf
u8_sprintfunistdio/u8-sprintf
u8_snprintfunistdio/u8-snprintf
u8_asprintfunistdio/u8-asprintf
u8_asnprintfunistdio/u8-asnprintf
u8_vsprintfunistdio/u8-vsprintf
u8_vsnprintfunistdio/u8-vsnprintf
u8_vasprintfunistdio/u8-vasprintf
u8_vasnprintfunistdio/u8-vasnprintf
u8_u8_sprintfunistdio/u8-u8-sprintf
u8_u8_snprintfunistdio/u8-u8-snprintf
u8_u8_asprintfunistdio/u8-u8-asprintf
u8_u8_asnprintfunistdio/u8-u8-asnprintf
u8_u8_vsprintfunistdio/u8-u8-vsprintf
u8_u8_vsnprintfunistdio/u8-u8-vsnprintf
u8_u8_vasprintfunistdio/u8-u8-vasprintf
u8_u8_vasnprintfunistdio/u8-u8-vasnprintf
u16_sprintfunistdio/u16-sprintf
u16_snprintfunistdio/u16-snprintf
u16_asprintfunistdio/u16-asprintf
u16_asnprintfunistdio/u16-asnprintf
u16_vsprintfunistdio/u16-vsprintf
u16_vsnprintfunistdio/u16-vsnprintf
u16_vasprintfunistdio/u16-vasprintf
u16_vasnprintfunistdio/u16-vasnprintf
u16_u16_sprintfunistdio/u16-u16-sprintf
u16_u16_snprintfunistdio/u16-u16-snprintf
u16_u16_asprintfunistdio/u16-u16-asprintf
u16_u16_asnprintfunistdio/u16-u16-asnprintf
u16_u16_vsprintfunistdio/u16-u16-vsprintf
u16_u16_vsnprintfunistdio/u16-u16-vsnprintf
u16_u16_vasprintfunistdio/u16-u16-vasprintf
u16_u16_vasnprintfunistdio/u16-u16-vasnprintf
u32_sprintfunistdio/u32-sprintf
u32_snprintfunistdio/u32-snprintf
u32_asprintfunistdio/u32-asprintf
u32_asnprintfunistdio/u32-asnprintf
u32_vsprintfunistdio/u32-vsprintf
u32_vsnprintfunistdio/u32-vsnprintf
u32_vasprintfunistdio/u32-vasprintf
u32_vasnprintfunistdio/u32-vasnprintf
u32_u32_sprintfunistdio/u32-u32-sprintf
u32_u32_snprintfunistdio/u32-u32-snprintf
u32_u32_asprintfunistdio/u32-u32-asprintf
u32_u32_asnprintfunistdio/u32-u32-asnprintf
u32_u32_vsprintfunistdio/u32-u32-vsprintf
u32_u32_vsnprintfunistdio/u32-u32-vsnprintf
u32_u32_vasprintfunistdio/u32-u32-vasprintf
u32_u32_vasnprintfunistdio/u32-u32-vasnprintf
ulc_fprintfunistdio/ulc-fprintf
ulc_vfprintfunistdio/ulc-vfprintf

Next: , Previous: , Up: The libunistring modules   [Contents][Index]

18.15.2.5 Declarations in <uniname.h>

FunctionModule
unicode_character_nameuniname/uniname
unicode_name_characteruniname/uniname

Next: , Previous: , Up: The libunistring modules   [Contents][Index]

18.15.2.6 Declarations in <unictype.h>

Function or constantModule
UC_CATEGORY_Lunictype/category-L
UC_CATEGORY_LCunictype/category-LC
UC_CATEGORY_Luunictype/category-Lu
UC_CATEGORY_Llunictype/category-Ll
UC_CATEGORY_Ltunictype/category-Lt
UC_CATEGORY_Lmunictype/category-Lm
UC_CATEGORY_Lounictype/category-Lo
UC_CATEGORY_Munictype/category-M
UC_CATEGORY_Mnunictype/category-Mn
UC_CATEGORY_Mcunictype/category-Mc
UC_CATEGORY_Meunictype/category-Me
UC_CATEGORY_Nunictype/category-N
UC_CATEGORY_Ndunictype/category-Nd
UC_CATEGORY_Nlunictype/category-Nl
UC_CATEGORY_Nounictype/category-No
UC_CATEGORY_Punictype/category-P
UC_CATEGORY_Pcunictype/category-Pc
UC_CATEGORY_Pdunictype/category-Pd
UC_CATEGORY_Psunictype/category-Ps
UC_CATEGORY_Peunictype/category-Pe
UC_CATEGORY_Piunictype/category-Pi
UC_CATEGORY_Pfunictype/category-Pf
UC_CATEGORY_Pounictype/category-Po
UC_CATEGORY_Sunictype/category-S
UC_CATEGORY_Smunictype/category-Sm
UC_CATEGORY_Scunictype/category-Sc
UC_CATEGORY_Skunictype/category-Sk
UC_CATEGORY_Sounictype/category-So
UC_CATEGORY_Zunictype/category-Z
UC_CATEGORY_Zsunictype/category-Zs
UC_CATEGORY_Zlunictype/category-Zl
UC_CATEGORY_Zpunictype/category-Zp
UC_CATEGORY_Cunictype/category-C
UC_CATEGORY_Ccunictype/category-Cc
UC_CATEGORY_Cfunictype/category-Cf
UC_CATEGORY_Csunictype/category-Cs
UC_CATEGORY_Counictype/category-Co
UC_CATEGORY_Cnunictype/category-Cn
uc_general_category_orunictype/category-or
uc_general_category_andunictype/category-and
uc_general_category_and_notunictype/category-and-not
uc_general_category_nameunictype/category-name
uc_general_category_long_nameunictype/category-longname
uc_general_category_bynameunictype/category-byname
uc_general_categoryunictype/category-of
uc_is_general_categoryunictype/category-test
uc_is_general_category_withtableunictype/category-test-withtable
uc_combining_class_nameunictype/combining-class-name
uc_combining_class_long_nameunictype/combining-class-longname
uc_combining_class_bynameunictype/combining-class-byname
uc_combining_classunictype/combining-class
uc_bidi_class_nameunictype/bidiclass-name
uc_bidi_category_nameunictype/bidiclass-name
uc_bidi_class_long_nameunictype/bidiclass-longname
uc_bidi_class_bynameunictype/bidiclass-byname
uc_bidi_category_bynameunictype/bidiclass-byname
uc_bidi_classunictype/bidiclass-of
uc_bidi_categoryunictype/bidiclass-of
uc_is_bidi_classunictype/bidiclass-test
uc_is_bidi_categoryunictype/bidiclass-test
uc_decimal_valueunictype/decimal-digit
uc_digit_valueunictype/digit
uc_numeric_valueunictype/numeric
uc_mirror_charunictype/mirror
uc_joining_type_nameunictype/joiningtype-name
uc_joining_type_long_nameunictype/joiningtype-longname
uc_joining_type_bynameunictype/joiningtype-byname
uc_joining_typeunictype/joiningtype-of
uc_joining_group_nameunictype/joininggroup-name
uc_joining_group_bynameunictype/joininggroup-byname
uc_joining_groupunictype/joininggroup-of
UC_PROPERTY_WHITE_SPACEunictype/property-white-space
UC_PROPERTY_ALPHABETICunictype/property-alphabetic
UC_PROPERTY_OTHER_ALPHABETICunictype/property-other-alphabetic
UC_PROPERTY_NOT_A_CHARACTERunictype/property-not-a-character
UC_PROPERTY_DEFAULT_IGNORABLE_CODE_POINTunictype/property-default-ignorable-code-point
UC_PROPERTY_OTHER_DEFAULT_IGNORABLE_CODE_POINTunictype/property-other-default-ignorable-code-point
UC_PROPERTY_DEPRECATEDunictype/property-deprecated
UC_PROPERTY_LOGICAL_ORDER_EXCEPTIONunictype/property-logical-order-exception
UC_PROPERTY_VARIATION_SELECTORunictype/property-variation-selector
UC_PROPERTY_PRIVATE_USEunictype/property-private-use
UC_PROPERTY_UNASSIGNED_CODE_VALUEunictype/property-unassigned-code-value
UC_PROPERTY_UPPERCASEunictype/property-uppercase
UC_PROPERTY_OTHER_UPPERCASEunictype/property-other-uppercase
UC_PROPERTY_LOWERCASEunictype/property-lowercase
UC_PROPERTY_OTHER_LOWERCASEunictype/property-other-lowercase
UC_PROPERTY_TITLECASEunictype/property-titlecase
UC_PROPERTY_CASEDunictype/property-cased
UC_PROPERTY_CASE_IGNORABLEunictype/property-case-ignorable
UC_PROPERTY_CHANGES_WHEN_LOWERCASEDunictype/property-changes-when-lowercased
UC_PROPERTY_CHANGES_WHEN_UPPERCASEDunictype/property-changes-when-uppercased
UC_PROPERTY_CHANGES_WHEN_TITLECASEDunictype/property-changes-when-titlecased
UC_PROPERTY_CHANGES_WHEN_CASEFOLDEDunictype/property-changes-when-casefolded
UC_PROPERTY_CHANGES_WHEN_CASEMAPPEDunictype/property-changes-when-casemapped
UC_PROPERTY_SOFT_DOTTEDunictype/property-soft-dotted
UC_PROPERTY_ID_STARTunictype/property-id-start
UC_PROPERTY_OTHER_ID_STARTunictype/property-other-id-start
UC_PROPERTY_ID_CONTINUEunictype/property-id-continue
UC_PROPERTY_OTHER_ID_CONTINUEunictype/property-other-id-continue
UC_PROPERTY_XID_STARTunictype/property-xid-start
UC_PROPERTY_XID_CONTINUEunictype/property-xid-continue
UC_PROPERTY_ID_COMPAT_MATH_STARTunictype/property-id-compat-math-start
UC_PROPERTY_ID_COMPAT_MATH_CONTINUEunictype/property-id-compat-math-continue
UC_PROPERTY_PATTERN_WHITE_SPACEunictype/property-pattern-white-space
UC_PROPERTY_PATTERN_SYNTAXunictype/property-pattern-syntax
UC_PROPERTY_JOIN_CONTROLunictype/property-join-control
UC_PROPERTY_GRAPHEME_BASEunictype/property-grapheme-base
UC_PROPERTY_GRAPHEME_EXTENDunictype/property-grapheme-extend
UC_PROPERTY_OTHER_GRAPHEME_EXTENDunictype/property-other-grapheme-extend
UC_PROPERTY_GRAPHEME_LINKunictype/property-grapheme-link
UC_PROPERTY_MODIFIER_COMBINING_MARKunictype/property-modifier-combining-mark
UC_PROPERTY_BIDI_CONTROLunictype/property-bidi-control
UC_PROPERTY_BIDI_LEFT_TO_RIGHTunictype/property-bidi-left-to-right
UC_PROPERTY_BIDI_HEBREW_RIGHT_TO_LEFTunictype/property-bidi-hebrew-right-to-left
UC_PROPERTY_BIDI_ARABIC_RIGHT_TO_LEFTunictype/property-bidi-arabic-right-to-left
UC_PROPERTY_BIDI_EUROPEAN_DIGITunictype/property-bidi-european-digit
UC_PROPERTY_BIDI_EUR_NUM_SEPARATORunictype/property-bidi-eur-num-separator
UC_PROPERTY_BIDI_EUR_NUM_TERMINATORunictype/property-bidi-eur-num-terminator
UC_PROPERTY_BIDI_ARABIC_DIGITunictype/property-bidi-arabic-digit
UC_PROPERTY_BIDI_COMMON_SEPARATORunictype/property-bidi-common-separator
UC_PROPERTY_BIDI_BLOCK_SEPARATORunictype/property-bidi-block-separator
UC_PROPERTY_BIDI_SEGMENT_SEPARATORunictype/property-bidi-segment-separator
UC_PROPERTY_BIDI_WHITESPACEunictype/property-bidi-whitespace
UC_PROPERTY_BIDI_NON_SPACING_MARKunictype/property-bidi-non-spacing-mark
UC_PROPERTY_BIDI_BOUNDARY_NEUTRALunictype/property-bidi-boundary-neutral
UC_PROPERTY_BIDI_PDFunictype/property-bidi-pdf
UC_PROPERTY_BIDI_EMBEDDING_OR_OVERRIDEunictype/property-bidi-embedding-or-override
UC_PROPERTY_BIDI_OTHER_NEUTRALunictype/property-bidi-other-neutral
UC_PROPERTY_HEX_DIGITunictype/property-hex-digit
UC_PROPERTY_ASCII_HEX_DIGITunictype/property-ascii-hex-digit
UC_PROPERTY_IDEOGRAPHICunictype/property-ideographic
UC_PROPERTY_UNIFIED_IDEOGRAPHunictype/property-unified-ideograph
UC_PROPERTY_RADICALunictype/property-radical
UC_PROPERTY_IDS_UNARY_OPERATORunictype/property-ids-unary-operator
UC_PROPERTY_IDS_BINARY_OPERATORunictype/property-ids-binary-operator
UC_PROPERTY_IDS_TRINARY_OPERATORunictype/property-ids-trinary-operator
UC_PROPERTY_EMOJIunictype/property-emoji
UC_PROPERTY_EMOJI_PRESENTATIONunictype/property-emoji-presentation
UC_PROPERTY_EMOJI_MODIFIERunictype/property-emoji-modifier
UC_PROPERTY_EMOJI_MODIFIER_BASEunictype/property-emoji-modifier-base
UC_PROPERTY_EMOJI_COMPONENTunictype/property-emoji-component
UC_PROPERTY_EXTENDED_PICTOGRAPHICunictype/property-extended-pictographic
UC_PROPERTY_ZERO_WIDTHunictype/property-zero-width
UC_PROPERTY_SPACEunictype/property-space
UC_PROPERTY_NON_BREAKunictype/property-non-break
UC_PROPERTY_ISO_CONTROLunictype/property-iso-control
UC_PROPERTY_FORMAT_CONTROLunictype/property-format-control
UC_PROPERTY_PREPENDED_CONCATENATION_MARKunictype/property-prepended-concatenation-mark
UC_PROPERTY_DASHunictype/property-dash
UC_PROPERTY_HYPHENunictype/property-hyphen
UC_PROPERTY_PUNCTUATIONunictype/property-punctuation
UC_PROPERTY_LINE_SEPARATORunictype/property-line-separator
UC_PROPERTY_PARAGRAPH_SEPARATORunictype/property-paragraph-separator
UC_PROPERTY_QUOTATION_MARKunictype/property-quotation-mark
UC_PROPERTY_SENTENCE_TERMINALunictype/property-sentence-terminal
UC_PROPERTY_TERMINAL_PUNCTUATIONunictype/property-terminal-punctuation
UC_PROPERTY_CURRENCY_SYMBOLunictype/property-currency-symbol
UC_PROPERTY_MATHunictype/property-math
UC_PROPERTY_OTHER_MATHunictype/property-other-math
UC_PROPERTY_PAIRED_PUNCTUATIONunictype/property-paired-punctuation
UC_PROPERTY_LEFT_OF_PAIRunictype/property-left-of-pair
UC_PROPERTY_COMBININGunictype/property-combining
UC_PROPERTY_COMPOSITEunictype/property-composite
UC_PROPERTY_DECIMAL_DIGITunictype/property-decimal-digit
UC_PROPERTY_NUMERICunictype/property-numeric
UC_PROPERTY_DIACRITICunictype/property-diacritic
UC_PROPERTY_EXTENDERunictype/property-extender
UC_PROPERTY_IGNORABLE_CONTROLunictype/property-ignorable-control
UC_PROPERTY_REGIONAL_INDICATORunictype/property-regional-indicator
uc_property_bynameunictype/property-byname
uc_property_is_validunictype/base
uc_is_propertyunictype/property-test
uc_is_property_white_spaceunictype/property-white-space
uc_is_property_alphabeticunictype/property-alphabetic
uc_is_property_other_alphabeticunictype/property-other-alphabetic
uc_is_property_not_a_characterunictype/property-not-a-character
uc_is_property_default_ignorable_code_pointunictype/property-default-ignorable-code-point
uc_is_property_other_default_ignorable_code_pointunictype/property-other-default-ignorable-code-point
uc_is_property_deprecatedunictype/property-deprecated
uc_is_property_logical_order_exceptionunictype/property-logical-order-exception
uc_is_property_variation_selectorunictype/property-variation-selector
uc_is_property_private_useunictype/property-private-use
uc_is_property_unassigned_code_valueunictype/property-unassigned-code-value
uc_is_property_uppercaseunictype/property-uppercase
uc_is_property_other_uppercaseunictype/property-other-uppercase
uc_is_property_lowercaseunictype/property-lowercase
uc_is_property_other_lowercaseunictype/property-other-lowercase
uc_is_property_titlecaseunictype/property-titlecase
uc_is_property_casedunictype/property-cased
uc_is_property_case_ignorableunictype/property-case-ignorable
uc_is_property_changes_when_lowercasedunictype/property-changes-when-lowercased
uc_is_property_changes_when_uppercasedunictype/property-changes-when-uppercased
uc_is_property_changes_when_titlecasedunictype/property-changes-when-titlecased
uc_is_property_changes_when_casefoldedunictype/property-changes-when-casefolded
uc_is_property_changes_when_casemappedunictype/property-changes-when-casemapped
uc_is_property_soft_dottedunictype/property-soft-dotted
uc_is_property_id_startunictype/property-id-start
uc_is_property_other_id_startunictype/property-other-id-start
uc_is_property_id_continueunictype/property-id-continue
uc_is_property_other_id_continueunictype/property-other-id-continue
uc_is_property_xid_startunictype/property-xid-start
uc_is_property_xid_continueunictype/property-xid-continue
uc_is_property_id_compat_math_startunictype/property-id-compat-math-start
uc_is_property_id_compat_math_continueunictype/property-id-compat-math-continue
uc_is_property_pattern_white_spaceunictype/property-pattern-white-space
uc_is_property_pattern_syntaxunictype/property-pattern-syntax
uc_is_property_join_controlunictype/property-join-control
uc_is_property_grapheme_baseunictype/property-grapheme-base
uc_is_property_grapheme_extendunictype/property-grapheme-extend
uc_is_property_other_grapheme_extendunictype/property-other-grapheme-extend
uc_is_property_grapheme_linkunictype/property-grapheme-link
uc_is_property_modifier_combining_markunictype/property-modifier-combining-mark
uc_is_property_bidi_controlunictype/property-bidi-control
uc_is_property_bidi_left_to_rightunictype/property-bidi-left-to-right
uc_is_property_bidi_hebrew_right_to_leftunictype/property-bidi-hebrew-right-to-left
uc_is_property_bidi_arabic_right_to_leftunictype/property-bidi-arabic-right-to-left
uc_is_property_bidi_european_digitunictype/property-bidi-european-digit
uc_is_property_bidi_eur_num_separatorunictype/property-bidi-eur-num-separator
uc_is_property_bidi_eur_num_terminatorunictype/property-bidi-eur-num-terminator
uc_is_property_bidi_arabic_digitunictype/property-bidi-arabic-digit
uc_is_property_bidi_common_separatorunictype/property-bidi-common-separator
uc_is_property_bidi_block_separatorunictype/property-bidi-block-separator
uc_is_property_bidi_segment_separatorunictype/property-bidi-segment-separator
uc_is_property_bidi_whitespaceunictype/property-bidi-whitespace
uc_is_property_bidi_non_spacing_markunictype/property-bidi-non-spacing-mark
uc_is_property_bidi_boundary_neutralunictype/property-bidi-boundary-neutral
uc_is_property_bidi_pdfunictype/property-bidi-pdf
uc_is_property_bidi_embedding_or_overrideunictype/property-bidi-embedding-or-override
uc_is_property_bidi_other_neutralunictype/property-bidi-other-neutral
uc_is_property_hex_digitunictype/property-hex-digit
uc_is_property_ascii_hex_digitunictype/property-ascii-hex-digit
uc_is_property_ideographicunictype/property-ideographic
uc_is_property_unified_ideographunictype/property-unified-ideograph
uc_is_property_radicalunictype/property-radical
uc_is_property_ids_unary_operatorunictype/property-ids-unary-operator
uc_is_property_ids_binary_operatorunictype/property-ids-binary-operator
uc_is_property_ids_trinary_operatorunictype/property-ids-trinary-operator
uc_is_property_emojiunictype/property-emoji
uc_is_property_emoji_presentationunictype/property-emoji-presentation
uc_is_property_emoji_modifierunictype/property-emoji-modifier
uc_is_property_emoji_modifier_baseunictype/property-emoji-modifier-base
uc_is_property_emoji_componentunictype/property-emoji-component
uc_is_property_extended_pictographicunictype/property-extended-pictographic
uc_is_property_zero_widthunictype/property-zero-width
uc_is_property_spaceunictype/property-space
uc_is_property_non_breakunictype/property-non-break
uc_is_property_iso_controlunictype/property-iso-control
uc_is_property_format_controlunictype/property-format-control
uc_is_property_prepended_concatenation_markunictype/property-prepended-concatenation-mark
uc_is_property_dashunictype/property-dash
uc_is_property_hyphenunictype/property-hyphen
uc_is_property_punctuationunictype/property-punctuation
uc_is_property_line_separatorunictype/property-line-separator
uc_is_property_paragraph_separatorunictype/property-paragraph-separator
uc_is_property_quotation_markunictype/property-quotation-mark
uc_is_property_sentence_terminalunictype/property-sentence-terminal
uc_is_property_terminal_punctuationunictype/property-terminal-punctuation
uc_is_property_currency_symbolunictype/property-currency-symbol
uc_is_property_mathunictype/property-math
uc_is_property_other_mathunictype/property-other-math
uc_is_property_paired_punctuationunictype/property-paired-punctuation
uc_is_property_left_of_pairunictype/property-left-of-pair
uc_is_property_combiningunictype/property-combining
uc_is_property_compositeunictype/property-composite
uc_is_property_decimal_digitunictype/property-decimal-digit
uc_is_property_numericunictype/property-numeric
uc_is_property_diacriticunictype/property-diacritic
uc_is_property_extenderunictype/property-extender
uc_is_property_ignorable_controlunictype/property-ignorable-control
uc_is_property_regional_indicatorunictype/property-regional-indicator
uc_indic_conjunct_break_nameunictype/incb-name
uc_indic_conjunct_break_bynameunictype/incb-byname
uc_indic_conjunct_breakunictype/incb-of
uc_scriptunictype/scripts
uc_script_bynameunictype/scripts
uc_is_scriptunictype/scripts
uc_all_scriptsunictype/scripts
uc_blockunictype/block-of
uc_is_blockunictype/block-test
uc_all_blocksunictype/block-list
uc_is_c_whitespaceunictype/syntax-c-whitespace
uc_is_java_whitespaceunictype/syntax-java-whitespace
uc_c_ident_categoryunictype/syntax-c-ident
uc_java_ident_categoryunictype/syntax-java-ident
uc_is_alnumunictype/ctype-alnum
uc_is_alphaunictype/ctype-alpha
uc_is_cntrlunictype/ctype-cntrl
uc_is_digitunictype/ctype-digit
uc_is_graphunictype/ctype-graph
uc_is_lowerunictype/ctype-lower
uc_is_printunictype/ctype-print
uc_is_punctunictype/ctype-punct
uc_is_spaceunictype/ctype-space
uc_is_upperunictype/ctype-upper
uc_is_xdigitunictype/ctype-xdigit
uc_is_blankunictype/ctype-blank

Next: , Previous: , Up: The libunistring modules   [Contents][Index]

18.15.2.7 Declarations in <uniwidth.h>

FunctionModule
uc_widthuniwidth/width
u8_widthuniwidth/u8-width
u16_widthuniwidth/u16-width
u32_widthuniwidth/u32-width
u8_strwidthuniwidth/u8-strwidth
u16_strwidthuniwidth/u16-strwidth
u32_strwidthuniwidth/u32-strwidth

Next: , Previous: , Up: The libunistring modules   [Contents][Index]

18.15.2.8 Declarations in <unigbrk.h>

FunctionModule
u8_grapheme_nextunigbrk/u8-grapheme-next
u16_grapheme_nextunigbrk/u16-grapheme-next
u32_grapheme_nextunigbrk/u32-grapheme-next
u8_grapheme_prevunigbrk/u8-grapheme-prev
u16_grapheme_prevunigbrk/u16-grapheme-prev
u32_grapheme_prevunigbrk/u32-grapheme-prev
u8_grapheme_breaksunigbrk/u8-grapheme-breaks
u16_grapheme_breaksunigbrk/u16-grapheme-breaks
u32_grapheme_breaksunigbrk/u32-grapheme-breaks
ulc_grapheme_breaksunigbrk/ulc-grapheme-breaks
uc_grapheme_breaksunigbrk/uc-grapheme-breaks
uc_graphemeclusterbreak_propertyunigbrk/uc-gbrk-prop
uc_is_grapheme_breakunigbrk/uc-is-grapheme-break

Next: , Previous: , Up: The libunistring modules   [Contents][Index]

18.15.2.9 Declarations in <uniwbrk.h>

FunctionModule
u8_wordbreaksuniwbrk/u8-wordbreaks
u16_wordbreaksuniwbrk/u16-wordbreaks
u32_wordbreaksuniwbrk/u32-wordbreaks
ulc_wordbreaksuniwbrk/ulc-wordbreaks
uc_wordbreak_propertyuniwbrk/wordbreak-property

Next: , Previous: , Up: The libunistring modules   [Contents][Index]

18.15.2.10 Declarations in <unilbrk.h>

FunctionModule
u8_possible_linebreaksunilbrk/u8-possible-linebreaks
u16_possible_linebreaksunilbrk/u16-possible-linebreaks
u32_possible_linebreaksunilbrk/u32-possible-linebreaks
ulc_possible_linebreaksunilbrk/ulc-possible-linebreaks
u8_width_linebreaksunilbrk/u8-width-linebreaks
u16_width_linebreaksunilbrk/u16-width-linebreaks
u32_width_linebreaksunilbrk/u32-width-linebreaks
ulc_width_linebreaksunilbrk/ulc-width-linebreaks

Next: , Previous: , Up: The libunistring modules   [Contents][Index]

18.15.2.11 Declarations in <uninorm.h>

Function or macroModule
uc_decompositionuninorm/decomposition
uc_canonical_decompositionuninorm/canonical-decomposition
uc_compositionuninorm/composition
UNINORM_NFDuninorm/nfd
UNINORM_NFCuninorm/nfc
UNINORM_NFKDuninorm/nfkd
UNINORM_NFKCuninorm/nfkc
uninorm_is_compat_decomposinguninorm/base
uninorm_is_composinguninorm/base
uninorm_decomposing_formuninorm/decomposing-form
u8_normalizeuninorm/u8-normalize
u16_normalizeuninorm/u16-normalize
u32_normalizeuninorm/u32-normalize
u8_normcmpuninorm/u8-normcmp
u16_normcmpuninorm/u16-normcmp
u32_normcmpuninorm/u32-normcmp
u8_normxfrmuninorm/u8-normxfrm
u16_normxfrmuninorm/u16-normxfrm
u32_normxfrmuninorm/u32-normxfrm
u8_normcolluninorm/u8-normcoll
u16_normcolluninorm/u16-normcoll
u32_normcolluninorm/u32-normcoll
uninorm_filter_createuninorm/filter
uninorm_filter_writeuninorm/filter
uninorm_filter_flushuninorm/filter
uninorm_filter_freeuninorm/filter

Previous: , Up: The libunistring modules   [Contents][Index]

18.15.2.12 Declarations in <unicase.h>

Function or constantModule
uc_toupperunicase/toupper
uc_tolowerunicase/tolower
uc_totitleunicase/totitle
uc_locale_languageunicase/locale-language
u8_toupperunicase/u8-toupper
u16_toupperunicase/u16-toupper
u32_toupperunicase/u32-toupper
u8_tolowerunicase/u8-tolower
u16_tolowerunicase/u16-tolower
u32_tolowerunicase/u32-tolower
u8_totitleunicase/u8-totitle
u16_totitleunicase/u16-totitle
u32_totitleunicase/u32-totitle
unicase_empty_prefix_contextunicase/empty-prefix-context
u8_casing_prefix_contextunicase/u8-prefix-context
u16_casing_prefix_contextunicase/u16-prefix-context
u32_casing_prefix_contextunicase/u32-prefix-context
u8_casing_prefixes_contextunicase/u8-prefix-context
u16_casing_prefixes_contextunicase/u16-prefix-context
u32_casing_prefixes_contextunicase/u32-prefix-context
unicase_empty_suffix_contextunicase/empty-suffix-context
u8_casing_suffix_contextunicase/u8-suffix-context
u16_casing_suffix_contextunicase/u16-suffix-context
u32_casing_suffix_contextunicase/u32-suffix-context
u8_casing_suffixes_contextunicase/u8-suffix-context
u16_casing_suffixes_contextunicase/u16-suffix-context
u32_casing_suffixes_contextunicase/u32-suffix-context
u8_ct_toupperunicase/u8-ct-toupper
u16_ct_toupperunicase/u16-ct-toupper
u32_ct_toupperunicase/u32-ct-toupper
u8_ct_tolowerunicase/u8-ct-tolower
u16_ct_tolowerunicase/u16-ct-tolower
u32_ct_tolowerunicase/u32-ct-tolower
u8_ct_totitleunicase/u8-ct-totitle
u16_ct_totitleunicase/u16-ct-totitle
u32_ct_totitleunicase/u32-ct-totitle
u8_casefoldunicase/u8-casefold
u16_casefoldunicase/u16-casefold
u32_casefoldunicase/u32-casefold
u8_ct_casefoldunicase/u8-ct-casefold
u16_ct_casefoldunicase/u16-ct-casefold
u32_ct_casefoldunicase/u32-ct-casefold
u8_casecmpunicase/u8-casecmp
u16_casecmpunicase/u16-casecmp
u32_casecmpunicase/u32-casecmp
ulc_casecmpunicase/ulc-casecmp
u8_casexfrmunicase/u8-casexfrm
u16_casexfrmunicase/u16-casexfrm
u32_casexfrmunicase/u32-casexfrm
ulc_casexfrmunicase/ulc-casexfrm
u8_casecollunicase/u8-casecoll
u16_casecollunicase/u16-casecoll
u32_casecollunicase/u32-casecoll
ulc_casecollunicase/ulc-casecoll
u8_is_uppercaseunicase/u8-is-uppercase
u16_is_uppercaseunicase/u16-is-uppercase
u32_is_uppercaseunicase/u32-is-uppercase
u8_is_lowercaseunicase/u8-is-lowercase
u16_is_lowercaseunicase/u16-is-lowercase
u32_is_lowercaseunicase/u32-is-lowercase
u8_is_titlecaseunicase/u8-is-titlecase
u16_is_titlecaseunicase/u16-is-titlecase
u32_is_titlecaseunicase/u32-is-titlecase
u8_is_casefoldedunicase/u8-is-casefolded
u16_is_casefoldedunicase/u16-is-casefolded
u32_is_casefoldedunicase/u32-is-casefolded
u8_is_casedunicase/u8-is-cased
u16_is_casedunicase/u16-is-cased
u32_is_casedunicase/u32-is-cased

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.16 Stack traces

Printing a stack trace was traditionally seen as a feature of the debugging environment and thus only implemented in the debuggers (gdb etc.). However, they are also useful in production code, for use in two circumstances:

  • When a problem occurs on a user’s machine, when the user is merely a user, not a programmer.
  • In unit tests that run in continuous-integration environments. In such environments, the virtual machine is discarded immediately after the tests have run. It is not possible to run a debugger in such environments.

And in fact, printing a stack trace is part of the basic runtime system in programming languages such as Java (printStackTrace method), Python (print_exception method), Go (PrintStack function), and ISO C++ 23 (std::stacktrace class).

Gnulib provides a module ‘stack-trace’ with this feature: print_stack_trace () prints a stack trace of the current thread to standard error.

For it to work best, three requirements need to be met:

When these requirements are not met, the function print_stack_trace () either prints a stack trace without source file names and line numbers, or prints nothing at all.

Gnulib also provides a module ‘abort-debug’, that overrides the abort function so that it prints the stack trace of the current thread, before actually aborting. Thus, abort () remains the idiom of choice for signaling a fatal situation that requires developer attention: it is useful both in debugging environments and production code.

Note: While the original abort function is safe to call in signal handlers, the overridden abort function is not. In signal handlers, you will need to call the original abort function, by doing #undef abort first.

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.17 Printing –version and bug-reporting information

Gnulib provides a few modules for printing --version and bug-reporting information according to the GNU Coding Standards; see https://www.gnu.org/prep/standards/html_node/_002d_002dversion.html#g_t_002d_002dversion

The ‘version-etc’ module defines functions used to emit --version and bug-reporting input in a standard way. The module expects the string version_etc_copyright to be defined to display the copyright holder along with the package release year. The version_etc function can then be used like so: 


const char version_etc_copyright[] = "Copyright %s %d copyright-holder";

int
main (void)
{
  version_etc (stdout, "my-program", "my-package", "1.0",
               "author1", "author2", (const char *) NULL);
  return 0;
}

The above example generates the following output: 

my-program (my-package) 1.0
Copyright (C) 2025 copyright-holder
License GPLv3+: GNU GPL version 3 or later <https://gnu.org/licenses/gpl.html>.
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.

Written by author1 and author2.

The ‘version-etc’ module also defines the function emit_bug_reporting_address which emits the bug-reporting location based on arguments passed to AC_INIT. For example, using the following in configure.ac: 

AC_INIT([gnulib], [0.0], [bug-gnulib@gnu.org], [gnulib],
        [https://www.gnu.org/software/gnulib/])

And the following program: 

#include <config.h>

#include "version-etc.h"

int
main (void)
{
  emit_bug_reporting_address ();
  return 0;
}

Will output: 

Report bugs to: bug-gnulib@gnu.org
gnulib home page: <https://www.gnu.org/software/gnulib/>
General help using GNU software: <https://www.gnu.org/gethelp/>

The ‘version-etc-fsf’ module defines and links to the variable version_etc_copyright containing copyright information for Free Software Foundation. This module should be used by programs which are FSF-copyrighted and use the ‘version-etc’ module.

The ‘argp-version-etc’ defines the argp_version_setup function takes the program name and authors as arguments. This function should be called before argp_parse since it modifies argp global variables; see https://www.gnu.org/software/libc/manual/html_node/Argp-Global-Variables.html.

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.18 Recognizing Option Arguments

The module ‘argmatch’ provides a simple textual user interface to a finite choice. It is for example well suited to recognize arguments of options or values of environment variables that accept a fixed set of valid choices.

These choices may be denoted by synonyms, such as ‘none’ and ‘off’ below. 

$ my_cp --backup=none foo bar
$ my_cp --backup=non foo bar
$ my_cp --backup=no foo bar
$ my_cp --backup=n foo bar
my_cp: ambiguous argument 'n' for 'backup type'
Valid arguments are:
  - 'no', 'none', 'off'
  - 'numbered', 't', 'newstyle'
  - 'existing', 'nil', 'numbered-existing'
  - 'simple', 'never', 'single'
Try 'my_cp --help' for more information.
$ my_cp --backup=num foo bar
$ my_cp --backup=true foo bar
my_cp: invalid argument 'true' for 'backup type'
Valid arguments are:
  - 'no', 'none', 'off'
  - 'numbered', 't', 'newstyle'
  - 'existing', 'nil', 'numbered-existing'
  - 'simple', 'never', 'single'
Try 'my_cp --help' for more information.

To set up argmatch, first call ‘ARGMATCH_DEFINE_GROUP (name, type)’ with the name of the argmatch group name, and the value type. For instance: 

enum backup_type
{
  no_backups,
  simple_backups,
  numbered_existing_backups,
  numbered_backups
};

ARGMATCH_DEFINE_GROUP (backup, enum backup_type);

This defines a few types and functions named argmatch_name_*. Introduce the array that defines the mapping from user-input to actual value, with a terminator: 

static const argmatch_backup_arg argmatch_backup_args[] =
{
  { "no",                no_backups },
  { "none",              no_backups },
  { "off",               no_backups },
  { "simple",            simple_backups },
  { "never",             simple_backups },
  { "single",            simple_backups },
  { "existing",          numbered_existing_backups },
  { "nil",               numbered_existing_backups },
  { "numbered-existing", numbered_existing_backups },
  { "numbered",          numbered_backups },
  { "t",                 numbered_backups },
  { "newstyle",          numbered_backups },
  { NULL, no_backups }
};

Then introduce the array that defines the values, also with a terminator. Document only once per group of synonyms: 

static const argmatch_backup_doc argmatch_backup_docs[] =
{
  { "no",       N_("never make backups (even if --backup is given)") },
  { "numbered", N_("make numbered backups") },
  { "existing", N_("numbered if numbered backups exist, simple otherwise") },
  { "simple",   N_("always make simple backups") },
  { NULL, NULL }
};

Finally, define the argmatch group: 

const argmatch_backup_group_type argmatch_backup_group =
{
  argmatch_backup_args,
  argmatch_backup_docs,
  N_("\
The backup suffix is '~', unless set with --suffix or SIMPLE_BACKUP_SUFFIX.\n\
The version control method may be selected via the --backup option or through\n\
the VERSION_CONTROL environment variable.  Here are the values:\n"),
  NULL
};

To use the argmatch group: 

ptrdiff_t i = argmatch_backup_choice ("--backup", "none");
// argmatch_backup_group.args[i].arg is "none", so its value
// is argmatch_backup_group.args[i].val.
// Return -1 on invalid argument, and -2 on ambiguity.

enum backup_type val = *argmatch_backup_value ("--backup", "none");
// Returns a pointer to the value, and exit on errors.
// So argmatch_backup_group.args[i].val == val.

const char *arg = argmatch_backup_argument (&no_backups);
// arg is "no".

// Print the documentation on stdout.
argmatch_backup_usage (stdout);
// Gives:
//
// The backup suffix is '~', unless set with --suffix or SIMPLE_BACKUP_SUFFIX.
// The version control method may be selected via the --backup option or through
// the VERSION_CONTROL environment variable.  Here are the values:
//
//   no, none, off  never make backups (even if --backup is given)
//   numbered, t, newstyle
//                  make numbered backups
//   existing, nil, numbered-existing
//                  numbered if numbered backups exist, simple otherwise
//   simple, never, single
//                  always make simple backups

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.19 Quoting

Gnulib provides ‘quote’ and ‘quotearg’ modules to help with quoting text, such as file names, in messages to the user. Here’s an example of using ‘quote’: 

#include <quote.h>
 ...
  error (0, errno, _("cannot change owner of %s"), quote (fname));

This differs from 

  error (0, errno, _("cannot change owner of '%s'"), fname);

in that quote escapes unusual characters in fname, e.g., ‘'’ and control characters like ‘\n’.

However, a caveat: quote reuses the storage that it returns. Hence if you need more than one thing quoted at the same time, you need to use quote_n.

Also, the quote module is not suited for multithreaded processes. In that case, you have to use quotearg_alloc, defined in the ‘quotearg’ module, which is decidedly less convenient.

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.20 progname and getprogname

Gnulib has two modules for retrieving the name of the currently executing program: progname and getprogname.

The progname module defines a variable program_name. It contains the name of the currently executing program, on all platforms. But it cannot be used implicitly: It requires that every main function be modified to invoke set_program_name (argv[0]) as one of its first actions.

The getprogname module defines a function getprogname(). It returns the name of the currently executing program, on most platforms. The advantage of this module is that it can be used without prior initializations. But it has limitations: In some rare situations, it cannot determine the name; then it returns "?" instead. And on some platforms, it returns a truncated program name.

The error function uses the getprogname module.

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.21 gcd: greatest common divisor

The gcd function returns the greatest common divisor of two numbers a > 0 and b > 0. It is the caller’s responsibility to ensure that the arguments are non-zero.

If you need a gcd function for an integer type larger than ‘unsigned long’, you can include the gcd.c implementation file with parametrization. The parameters are:

  • WORD_T Define this to the unsigned integer type that you need this function for.
  • GCD Define this to the name of the function to be created.

The created function has the prototype 

WORD_T GCD (WORD_T a, WORD_T b);

If you need the least common multiple of two numbers, it can be computed like this: lcm(a,b) = (a / gcd(a,b)) * b or lcm(a,b) = a * (b / gcd(a,b)). Avoid the formula lcm(a,b) = (a * b) / gcd(a,b) because—although mathematically correct—it can yield a wrong result, due to integer overflow.

In some applications it is useful to have a function taking the gcd of two signed numbers. In this case, the gcd function result is usually normalized to be non-negative (so that two gcd results can be compared in magnitude or compared against 1, etc.). Note that in this case the prototype of the function has to be 

unsigned long gcd (long a, long b);

and not 

long gcd (long a, long b);

because gcd(LONG_MIN,LONG_MIN) = -LONG_MIN = LONG_MAX + 1 does not fit into a signed ‘long’.

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.22 Profiling of program phases

The module ‘timevar’ provides a simple self-profiling facility, based on timers. 

Execution times (seconds)
read                  :   0.09 (19%) usr   0.08 (80%) sys   0.09 (18%) wall
read: scan            :   0.04 ( 9%) usr   0.08 (80%) sys   0.12 (26%) wall
read: parse           :   0.05 (10%) usr   0.00 ( 0%) sys   0.05 (10%) wall
work                  :   0.33 (70%) usr   0.00 ( 0%) sys   0.35 (71%) wall
work: phase 1         :   0.30 (64%) usr   0.00 ( 0%) sys   0.30 (64%) wall
work: phase 2         :   0.13 (28%) usr   0.00 ( 0%) sys   0.14 (29%) wall
output                :   0.04 ( 9%) usr   0.02 (20%) sys   0.04 ( 8%) wall
total time            :   0.47             0.10             0.49

To set up timevar, copy the stub file gnulib/lib/timevar.def next to where timevar.h and timevar.c were imported in your project, and define your timers there. For instance: 

/* The total execution time.  Mandatory.  */
DEFTIMEVAR (tv_total,      "total time")

/* Examples.  */
DEFTIMEVAR (tv_read,       "read")
DEFTIMEVAR (tv_work,       "work")
DEFTIMEVAR (tv_work_1,     "work: phase 1")
DEFTIMEVAR (tv_work_2,     "work: phase 2")
DEFTIMEVAR (tv_output,     "output")

Do not remove tv_total, it is mandatory. You may change its associated string.


Use timevar_push/timevar_pop to start/stop timers, as in the following example. 

#include <config.h>
#include "timevar.h"

#include <stdio.h>
#include "read.h"
#include "work.h"
#include "output.h"

int
main (void)
{
  timevar_enabled = true;
  timevar_init ();
  timevar_start (tv_total);

  timevar_push (tv_read);
  reader ();
  timevar_pop (tv_read);

  timevar_push (tv_work);
  work ();
  timevar_pop (tv_work);

  timevar_push (tv_output);
  output ();
  timevar_pop (tv_output);

  timevar_stop (tv_total);
  timevar_print (stderr);
}

with, for instance, in work.c 

#include <config.h>
#include "work.h"

void
work (void)
{
  timevar_push (tv_work_phase1);
  work1 ();
  timevar_pop (tv_work_phase1);

  timevar_push (tv_work_phase2);
  work2 ();
  timevar_pop (tv_work_phase2);
}

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.23 Library version handling

The module ‘check-version’ can be useful when your gnulib application is a system library. You will typically wrap the call to the check_version function through a library API, your library header file may contain: 

#define STRINGPREP_VERSION "0.5.18"
...
  extern const char *stringprep_check_version (const char *req_version);

To avoid ELF symbol collisions with other libraries that use the ‘check-version’ module, add to config.h through a AC_DEFINE something like: 

AC_DEFINE(check_version, stringprep_check_version,
          [Rename check_version.])

The stringprep_check_version function will thus be implemented by the check_version module.

There are two uses of the interface. The first is a way to provide for applications to find out the version number of the library it uses. The application may contain diagnostic code such as: 

  printf ("Stringprep version: header %s library %s",
          STRINGPREP_VERSION,
          stringprep_check_version (NULL));

Separating the library and header file version can be useful when searching for version mismatch related problems.

The second uses is as a rudimentary test of proper library version, by making sure the application get a library version that is the same, or newer, than the header file used when building the application. This doesn’t catch all problems, libraries may change backwards incompatibly in later versions, but enable applications to require a certain minimum version before it may proceed.

Typical uses look like: 

       /* Check version of libgcrypt. */
       if (!gcry_check_version (GCRYPT_VERSION))
         die ("version mismatch\n");

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.24 Supporting Relocation

It has been a pain for many users of GNU packages for a long time that packages are not relocatable. It means a user cannot copy a program, installed by another user on the same machine, to his home directory, and have it work correctly (including i18n). So many users need to go through configure; make; make install with all its dependencies, options, and hurdles.

Red Hat, Debian, and other binary distributions solve the “ease of installation” problem, but they hardwire path names, usually to /usr or /usr/local. This means that users need root privileges to install a binary package, and prevents installing two different versions of the same binary package.

A relocatable program can be moved or copied to a different location on the file system. It is possible to make symlinks to the installed and moved programs, and invoke them through the symlink. It is possible to do the same thing with a hard link only if the hard link file is in the same directory as the real program.

The relocatable-prog module aims to ease the process of making a GNU program relocatable. It helps overcome two obstacles. First, it aids with relocating the hard-coded references to absolute file names that GNU programs often contain. These references must be fixed up at runtime if a program is to be successfully relocated. The relocatable-prog module provides a function relocate that does this job.

Second, the loader must be able to find shared libraries linked to relocatable executables or referenced by other shared libraries linked to relocatable executables. The relocatable-prog module helps out here in a platform-specific way:

  • On most operating systems, it adds a linker option (-rpath) that causes the dynamic linker to search for libraries in a directory relative to the location of the invoked executable. This works on GNU/Linux and modern versions of GNU/Hurd, GNU/kFreeBSD, macOS, FreeBSD, NetBSD, OpenBSD, Solaris, Haiku.
  • On other Unix systems, it installs a trampoline executable. The trampoline sets the environment variable that controls shared library searching (usually LD_LIBRARY_PATH) and then invokes the real executable. This applies to operating systems such as AIX, HP-UX, or Minix.
  • On Windows, the executable’s own directory is searched for libraries, so installing shared libraries into the executable’s directory is sufficient.

You can make your program relocatable by following these steps:

  1. Import the relocatable-prog module. For libraries, use the relocatable-lib or relocatable-lib-lgpl module, if the libraries are independent. For installing multiple libraries, at least one of which depends on another one, use the relocatable-prog module. If you need more than one module, or you need to use them with different settings, you will need multiple copies of gnulib (see Using Gnulib for both a library and a program).
  2. In every program, add to main as the first statement (even before setting the locale or doing anything related to libintl): 
    set_program_name (argv[0]);

    The prototype for this function is in progname.h.

  3. If you want your code to be portable to platforms that do not support automatic initialization, call set_relocation_prefix.
  4. Everywhere where you use a constant pathname from installation-time, wrap it in relocate so it gets translated to the run-time situation. Example: 
    bindtextdomain (PACKAGE, LOCALEDIR);

    becomes: 

    bindtextdomain (PACKAGE, relocate (LOCALEDIR));

    The prototype for this function is in relocatable.h.

    There is also a variant of this function, named relocate2, that makes it easy to reclaim the memory allocated by the call.

  5. The set_program_name function can also configure some additional libraries to relocate files that they access, by defining corresponding C preprocessor symbols to 1. The libraries for which this is supported and the corresponding preprocessor symbols are:
    libcharset

    DEPENDS_ON_LIBCHARSET

    libiconv

    DEPENDS_ON_LIBICONV

    libintl

    DEPENDS_ON_LIBINTL

    Defining the symbol for a library makes every program in the package depend on that library, whether the program really uses the library or not, so this feature should be used with some caution.

  6. If your package installs shell scripts, also import the relocatable-script module. Then, near the beginning of each shell script that your package installs, add the following: 
    @relocatable_sh@

prefix="@prefix@"
exec_prefix="@exec_prefix@"   # usually needs $prefix.
datarootdir="@datarootdir@"   # usually needs $prefix.

if test "@RELOCATABLE@" = yes; then
  bindir="@bindir@"
  orig_installdir="$bindir" # see Makefile.am's *_SCRIPTS variables
  func_find_curr_installdir # determine curr_installdir
  func_find_prefixes
  relocate () {
    echo "$1/" \
    | sed -e "s%^${orig_installprefix}/%${curr_installprefix}/%" \
    | sed -e 's,/$,,'
  }
else
  relocate () {
    echo "$1"
  }
fi

# Get some relocated directory names.
sysconfdir=`relocate "@sysconfdir@"`          # usually needs $prefix.
some_datadir=`relocate "@datadir@/something"` # usually needs $datarootdir.
bindir=`relocate "@bindir@"`       # usually needs $exec_prefix, hence $prefix.

    You must adapt the definition of orig_installdir, depending on where the script gets installed. Also, at the end, instead of sysconfdir and some_datadir, transform those variables that you need.

  7. If your package installs Perl scripts, also import the relocatable-perl module. Then, near the beginning of each Perl script that your package installs, add the following: 
    @relocatable_pl@
if ("@RELOCATABLE@" eq "yes") {
  my $exec_prefix = "@exec_prefix@";
  my $orig_installdir = "@bindir@"; # see Makefile.am's *_SCRIPTS variables
  my ($orig_installprefix, $curr_installprefix) =
    find_prefixes($orig_installdir, find_curr_installdir());

  # the subroutine is defined whether or not the enclosing block is executed
  sub relocate {
    my ($dir) = @_;
    if ("@RELOCATABLE@" eq "yes") {
      $dir =~ s%^$orig_installprefix/%$curr_installprefix/%;
      $dir =~ s,/$,,;
    }
    return $dir;
  }
}

# Get some relocated directory names.
# (The gnulib module 'configmake' can help with this.)
$sysconfdir = relocate("@sysconfdir@");
$some_datadir = relocate(@datadir@/something");

    You must adapt the definition of $orig_installdir, depending on where the script gets installed. Also, at the end, instead of sysconfdir and some_datadir, transform those variables that you need.

  8. In your Makefile.am, for every program foo that gets installed in, say, $(bindir), you add: 
    foo_CPPFLAGS = -DINSTALLDIR=$(bindir_c_make)
if RELOCATABLE_VIA_LD
foo_LDFLAGS = `$(RELOCATABLE_LDFLAGS) $(bindir)`
endif

    Similarly, if a program foo gets installed in $(pkglibdir), you add: 

    foo_CPPFLAGS = -DINSTALLDIR=$(pkglibdir_c_make)
if RELOCATABLE_VIA_LD
foo_LDFLAGS = `$(RELOCATABLE_LDFLAGS) $(pkglibdir)`
endif

    The Makefile variables bindir_c_make or pkglibdir_c_make get defined by the Autoconf macros gl_BUILD_TO_HOST_BINDIR or gl_BUILD_TO_HOST_PKGLIBDIR, respectively. These Autoconf macros are defined in the file m4/build-to-host.m4. You need to

    • Import this file m4/build-to-host.m4 into your package, for example by using of a command like ‘gnulib-tool --copy m4/build-to-host.m4’.
    • Invoke the corresponding macro(s) from your package’s configure.ac.
  9. When building gnulib to use with a relocatable library, you need to define the preprocessor symbol IN_LIBRARY. You may also want to build with ENABLE_COSTLY_RELOCATABLE, in which case you will also need to define INSTALLDIR. The following fragment can be added to an override Makefile.am used to build gnulib (see Modifying the build rules of a Gnulib import directory). 
    AM_CPPFLAGS += -DIN_LIBRARY -DENABLE_COSTLY_RELOCATABLE

if SHLIBS_IN_BINDIR
AM_CPPFLAGS += -DINSTALLDIR=$(bindir_c_make)
else
AM_CPPFLAGS += -DINSTALLDIR=$(libdir_c_make)
endif

    SHLIBS_IN_BINDIR is defined in configure.ac as follows: 

    AM_CONDITIONAL([SHLIBS_IN_BINDIR],
               [case "$host_os" in mingw* | cygwin*) true;; *) false;; esac])
  10. In your Makefile.am, for every library libfoo that gets installed in, say, $(libdir), you add: 
    if RELOCATABLE_VIA_LD
libfoo_la_LDFLAGS = `$(RELOCATABLE_LDFLAGS) $(libdir)`
endif
  11. Add a couple of variable assignments to your Makefile.am.

    If your package (or any package you rely on, e.g. gettext-runtime) will be relocated together with a set of installed shared libraries, then set RELOCATABLE_LIBRARY_PATH to a colon-separated list of those libraries’ directories, e.g. 

    RELOCATABLE_LIBRARY_PATH = $(libdir)

    If your config.h is not in $(top_builddir), then set RELOCATABLE_CONFIG_H_DIR to its directory, e.g. 

    RELOCATABLE_CONFIG_H_DIR = $(top_builddir)/src

Next: , Previous: , Up: Particular Modules   [Contents][Index]

18.25 func

The func module makes sure that you can use the predefined identifier __func__ as defined by C99 in your code.

A small example is: 

#include <config.h>
#include <stdio.h> /* for printf */

int main (void)
{
    printf ("%s: hello world\n", __func__);
}

Note that sizeof cannot be applied to __func__: On SunPRO C compiler, sizeof __func__ evaluates to 0.

Previous: , Up: Particular Modules   [Contents][Index]

18.26 stat-size

The stat-size module provides a small number of macros intended for interpreting the file size information in an instance of struct stat.

On POSIX systems, the st_blocks member of struct stat contains the number of disk blocks occupied by a file. The ST_NBLOCKS and STP_NBLOCKS macros estimate this quantity on systems which don’t actually have st_blocks. Each of these blocks contains ST_NBLOCKSIZE bytes.

The value of ST_NBLOCKSIZE is often quite small, small enough that performing I/O in chunks that size would be inefficient. The ST_BLKSIZE and STP_BLKSIZE macros give the I/O block size recommended for I/O to this file. This is not guaranteed to give optimum performance, but it should be reasonably efficient.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

19 Regular expressions

Next: , Up: Regular expressions   [Contents][Index]

19.1 Overview

A regular expression (or regexp, or pattern) is a text string that describes some (mathematical) set of strings. A regexp r matches a string s if s is in the set of strings described by r.

Using the Regex library, you can:

  • see if a string matches a specified pattern as a whole, and
  • search within a string for a substring matching a specified pattern.

Some regular expressions match only one string, i.e., the set they describe has only one member. For example, the regular expression ‘foo’ matches the string ‘foo’ and no others. Other regular expressions match more than one string, i.e., the set they describe has more than one member. For example, the regular expression ‘f*’ matches the set of strings made up of any number (including zero) of ‘f’s. As you can see, some characters in regular expressions match themselves (such as ‘f’) and some don’t (such as ‘*’); the ones that don’t match themselves instead let you specify patterns that describe many different strings.

To either match or search for a regular expression with the Regex library functions, you must first compile it with a Regex pattern compiling function. A compiled pattern is a regular expression converted to the internal format used by the library functions. Once you’ve compiled a pattern, you can use it for matching or searching any number of times.

The Regex library is used by including regex.h. Regex provides three groups of functions with which you can operate on regular expressions. One group—the GNU group—is more powerful but not completely compatible with the other two, namely the POSIX and Berkeley Unix groups; its interface was designed specifically for GNU.

We wrote this chapter with programmers in mind, not users of programs—such as Emacs—that use Regex. We describe the Regex library in its entirety, not how to write regular expressions that a particular program understands.

Next: , Previous: , Up: Regular expressions   [Contents][Index]

19.2 Regular Expression Syntax

Characters are things you can type. Operators are things in a regular expression that match one or more characters. You compose regular expressions from operators, which in turn you specify using one or more characters.

Most characters represent what we call the match-self operator, i.e., they match themselves; we call these characters ordinary. Other characters represent either all or parts of fancier operators; e.g., ‘.’ represents what we call the match-any-character operator (which, no surprise, matches (almost) any character); we call these characters special. Two different things determine what characters represent what operators:

  1. the regular expression syntax your program has told the Regex library to recognize, and
  2. the context of the character in the regular expression.

In the following sections, we describe these things in more detail.

Next: , Up: Regular Expression Syntax   [Contents][Index]

19.2.1 Syntax Bits

In any particular syntax for regular expressions, some characters are always special, others are sometimes special, and others are never special. The particular syntax that Regex recognizes for a given regular expression depends on the current syntax (as set by re_set_syntax) when the pattern buffer of that regular expression was compiled.

You get a pattern buffer by compiling a regular expression. See GNU Pattern Buffers, for more information on pattern buffers. See GNU Regular Expression Compiling, and BSD Regular Expression Compiling, for more information on compiling.

Regex considers the current syntax to be a collection of bits; we refer to these bits as syntax bits. In most cases, they affect what characters represent what operators. We describe the meanings of the operators to which we refer in Common Operators and GNU Operators.

For reference, here is the complete list of syntax bits, in alphabetical order:

RE_BACKSLASH_ESCAPE_IN_LISTS

If this bit is set, then ‘\’ inside a list (see List Operators ([ … ] and [^ … ])) quotes (makes ordinary, if it’s special) the following character; if this bit isn’t set, then ‘\’ is an ordinary character inside lists. (See The Backslash Character, for what ‘\’ does outside of lists.)

RE_BK_PLUS_QM

If this bit is set, then ‘\+’ represents the match-one-or-more operator and ‘\?’ represents the match-zero-or-more operator; if this bit isn’t set, then ‘+’ represents the match-one-or-more operator and ‘?’ represents the match-zero-or-one operator. This bit is irrelevant if RE_LIMITED_OPS is set.

RE_CHAR_CLASSES

If this bit is set, then you can use character classes in lists; if this bit isn’t set, then you can’t.

RE_CONTEXT_INDEP_ANCHORS

If this bit is set, then ‘^’ and ‘$’ are special anywhere outside a list; if this bit isn’t set, then these characters are special only in certain contexts. See The Match-beginning-of-line Operator (^), and The Match-end-of-line Operator ($).

RE_CONTEXT_INDEP_OPS

If this bit is set, then certain characters are special anywhere outside a list; if this bit isn’t set, then those characters are special only in some contexts and are ordinary elsewhere. Specifically, if this bit isn’t set then ‘*’, and (if the syntax bit RE_LIMITED_OPS isn’t set) ‘+’ and ‘?’ (or ‘\+’ and ‘\?’, depending on the syntax bit RE_BK_PLUS_QM) represent repetition operators only if they’re not first in a regular expression or just after an open-group or alternation operator. The same holds for ‘{’ (or ‘\{’, depending on the syntax bit RE_NO_BK_BRACES) if it is the beginning of a valid interval and the syntax bit RE_INTERVALS is set.

RE_CONTEXT_INVALID_DUP

If this bit is set, then an open-interval operator cannot occur at the start of a regular expression, or immediately after an alternation, open-group or close-interval operator.

RE_CONTEXT_INVALID_OPS

If this bit is set, then repetition and alternation operators can’t be in certain positions within a regular expression. Specifically, the regular expression is invalid if it has:

  • a repetition operator first in the regular expression or just after a match-beginning-of-line, open-group, or alternation operator; or
  • an alternation operator first or last in the regular expression, just before a match-end-of-line operator, or just after an alternation or open-group operator.

If this bit isn’t set, then you can put the characters representing the repetition and alternation characters anywhere in a regular expression. Whether or not they will in fact be operators in certain positions depends on other syntax bits.

RE_DEBUG

If this bit is set, and the regex library was compiled with -DDEBUG, then internal debugging is turned on; if unset, then it is turned off.

RE_DOT_NEWLINE

If this bit is set, then the match-any-character operator matches a newline; if this bit isn’t set, then it doesn’t.

RE_DOT_NOT_NULL

If this bit is set, then the match-any-character operator doesn’t match a null character; if this bit isn’t set, then it does.

RE_HAT_LISTS_NOT_NEWLINE

If this bit is set, nonmatching lists ‘[^...]’ do not match newline; if not set, they do.

RE_ICASE

If this bit is set, then ignore case when matching; otherwise, case is significant.

RE_INTERVALS

If this bit is set, then Regex recognizes interval operators; if this bit isn’t set, then it doesn’t.

RE_INVALID_INTERVAL_ORD

If this bit is set, a syntactically invalid interval is treated as a string of ordinary characters. For example, the extended regular expression ‘a{1’ is treated as ‘a\{1’.

RE_LIMITED_OPS

If this bit is set, then Regex doesn’t recognize the match-one-or-more, match-zero-or-one or alternation operators; if this bit isn’t set, then it does.

RE_NEWLINE_ALT

If this bit is set, then newline represents the alternation operator; if this bit isn’t set, then newline is ordinary.

RE_NO_BK_BRACES

If this bit is set, then ‘{’ represents the open-interval operator and ‘}’ represents the close-interval operator; if this bit isn’t set, then ‘\{’ represents the open-interval operator and ‘\}’ represents the close-interval operator. This bit is relevant only if RE_INTERVALS is set.

RE_NO_BK_PARENS

If this bit is set, then ‘(’ represents the open-group operator and ‘)’ represents the close-group operator; if this bit isn’t set, then ‘\(’ represents the open-group operator and ‘\)’ represents the close-group operator.

RE_NO_BK_REFS

If this bit is set, then Regex doesn’t recognize ‘\’digit as the back-reference operator; if this bit isn’t set, then it does.

RE_NO_BK_VBAR

If this bit is set, then ‘|’ represents the alternation operator; if this bit isn’t set, then ‘\|’ represents the alternation operator. This bit is irrelevant if RE_LIMITED_OPS is set.

RE_NO_EMPTY_RANGES

If this bit is set, then a regular expression with a range whose ending point collates lower than its starting point is invalid; if this bit isn’t set, then Regex considers such a range to be empty.

RE_NO_GNU_OPS

If this bit is set, GNU regex operators are not recognized; otherwise, they are.

RE_NO_POSIX_BACKTRACKING

If this bit is set, succeed as soon as we match the whole pattern, without further backtracking. This means that a match may not be the leftmost longest; see What Gets Matched? for what this means.

RE_NO_SUB

If this bit is set, then no_sub will be set to one during re_compile_pattern. This causes matching and searching routines not to record substring match information.

RE_UNMATCHED_RIGHT_PAREN_ORD

If this bit is set and the regular expression has no matching open-group operator, then Regex considers what would otherwise be a close-group operator (based on how RE_NO_BK_PARENS is set) to match ‘)’.

Next: , Previous: , Up: Regular Expression Syntax   [Contents][Index]

19.2.2 Predefined Syntaxes

If you’re programming with Regex, you can set a pattern buffer’s (see GNU Pattern Buffers) syntax either to an arbitrary combination of syntax bits (see Syntax Bits) or else to the configurations defined by Regex. These configurations define the syntaxes used by certain programs—GNU Emacs, POSIX Awk, traditional Awk, Grep, Egrep—in addition to syntaxes for POSIX basic and extended regular expressions.

The predefined syntaxes—taken directly from regex.h—are: 

# define RE_SYNTAX_EMACS                                                \
  (RE_CHAR_CLASSES | RE_INTERVALS)

#define RE_SYNTAX_AWK                                                   \
  (RE_BACKSLASH_ESCAPE_IN_LISTS | RE_DOT_NOT_NULL                       \
   | RE_NO_BK_PARENS            | RE_NO_BK_REFS                         \
   | RE_NO_BK_VBAR               | RE_NO_EMPTY_RANGES                   \
   | RE_UNMATCHED_RIGHT_PAREN_ORD)

#define RE_SYNTAX_POSIX_AWK                                             \
  (RE_SYNTAX_POSIX_EXTENDED | RE_BACKSLASH_ESCAPE_IN_LISTS)

#define RE_SYNTAX_GREP                                                  \
  (RE_BK_PLUS_QM              | RE_CHAR_CLASSES                         \
   | RE_HAT_LISTS_NOT_NEWLINE | RE_INTERVALS                            \
   | RE_NEWLINE_ALT)

#define RE_SYNTAX_EGREP                                                 \
  (RE_CHAR_CLASSES        | RE_CONTEXT_INDEP_ANCHORS                    \
   | RE_CONTEXT_INDEP_OPS | RE_HAT_LISTS_NOT_NEWLINE                    \
   | RE_NEWLINE_ALT       | RE_NO_BK_PARENS                             \
   | RE_NO_BK_VBAR)

#define RE_SYNTAX_POSIX_EGREP                                           \
  (RE_SYNTAX_EGREP | RE_INTERVALS | RE_NO_BK_BRACES)

/* P1003.2/D11.2, section 4.20.7.1, lines 5078ff.  */
#define RE_SYNTAX_ED RE_SYNTAX_POSIX_BASIC

#define RE_SYNTAX_SED RE_SYNTAX_POSIX_BASIC

/* Syntax bits common to both basic and extended POSIX regex syntax.  */
#define _RE_SYNTAX_POSIX_COMMON                                         \
  (RE_CHAR_CLASSES | RE_DOT_NEWLINE      | RE_DOT_NOT_NULL              \
   | RE_INTERVALS  | RE_NO_EMPTY_RANGES)

#define RE_SYNTAX_POSIX_BASIC                                           \
  (_RE_SYNTAX_POSIX_COMMON | RE_BK_PLUS_QM)

/* Differs from ..._POSIX_BASIC only in that RE_BK_PLUS_QM becomes
   RE_LIMITED_OPS, i.e., \? \+ \| are not recognized.  Actually, this
   isn't minimal, since other operators, such as \`, aren't disabled.  */
#define RE_SYNTAX_POSIX_MINIMAL_BASIC                                   \
  (_RE_SYNTAX_POSIX_COMMON | RE_LIMITED_OPS)

#define RE_SYNTAX_POSIX_EXTENDED                                        \
  (_RE_SYNTAX_POSIX_COMMON | RE_CONTEXT_INDEP_ANCHORS                   \
   | RE_CONTEXT_INDEP_OPS  | RE_NO_BK_BRACES                            \
   | RE_NO_BK_PARENS       | RE_NO_BK_VBAR                              \
   | RE_UNMATCHED_RIGHT_PAREN_ORD)

/* Differs from ..._POSIX_EXTENDED in that RE_CONTEXT_INVALID_OPS
   replaces RE_CONTEXT_INDEP_OPS and RE_NO_BK_REFS is added.  */
#define RE_SYNTAX_POSIX_MINIMAL_EXTENDED                                \
  (_RE_SYNTAX_POSIX_COMMON  | RE_CONTEXT_INDEP_ANCHORS                  \
   | RE_CONTEXT_INVALID_OPS | RE_NO_BK_BRACES                           \
   | RE_NO_BK_PARENS        | RE_NO_BK_REFS                             \
   | RE_NO_BK_VBAR          | RE_UNMATCHED_RIGHT_PAREN_ORD)

Next: , Previous: , Up: Regular Expression Syntax   [Contents][Index]

19.2.3 Collating Elements vs. Characters

POSIX generalizes the notion of a character to that of a collating element. It defines a collating element to be “a sequence of one or more bytes defined in the current collating sequence as a unit of collation.”

This generalizes the notion of a character in two ways. First, a single character can map into two or more collating elements. For example, the German “ß” collates as the collating element ‘s’ followed by another collating element ‘s’. Second, two or more characters can map into one collating element. For example, the Czech ‘ch’ collates after ‘h’ and before ‘i’.

Since POSIX’s “collating element” preserves the essential idea of a “character,” we use the latter, more familiar, term in this document.

Previous: , Up: Regular Expression Syntax   [Contents][Index]

19.2.4 The Backslash Character

The ‘\’ character has one of four different meanings, depending on the context in which you use it and what syntax bits are set (see Syntax Bits). It can: 1) stand for itself, 2) quote the next character, 3) introduce an operator, or 4) do nothing.

  1. It stands for itself inside a list (see List Operators ([ … ] and [^ … ])) if the syntax bit RE_BACKSLASH_ESCAPE_IN_LISTS is not set. For example, ‘[\]’ would match ‘\’.
  2. It quotes (makes ordinary, if it’s special) the next character when you use it either:
    • outside a list,3 or
    • inside a list and the syntax bit RE_BACKSLASH_ESCAPE_IN_LISTS is set.
  3. It introduces an operator when followed by certain ordinary characters—sometimes only when certain syntax bits are set. See the cases RE_BK_PLUS_QM, RE_NO_BK_BRACES, RE_NO_BK_VAR, RE_NO_BK_PARENS, RE_NO_BK_REF in Syntax Bits. Also:
  4. In all other cases, Regex ignores ‘\’. For example, ‘\n’ matches ‘n’.

Next: , Previous: , Up: Regular expressions   [Contents][Index]

19.3 Common Operators

You compose regular expressions from operators. In the following sections, we describe the regular expression operators specified by POSIX; GNU also uses these. Most operators have more than one representation as characters. See Regular Expression Syntax, for what characters represent what operators under what circumstances.

For most operators that can be represented in two ways, one representation is a single character and the other is that character preceded by ‘\’. For example, either ‘(’ or ‘\(’ represents the open-group operator. Which one does depends on the setting of a syntax bit, in this case RE_NO_BK_PARENS. Why is this so? Historical reasons dictate some of the varying representations, while POSIX dictates others.

Finally, almost all characters lose any special meaning inside a list (see List Operators ([ … ] and [^ … ])).

Next: , Up: Common Operators   [Contents][Index]

19.3.1 The Match-self Operator (ordinary character)

This operator matches the character itself. All ordinary characters (see Regular Expression Syntax) represent this operator. For example, ‘f’ is always an ordinary character, so the regular expression ‘f’ matches only the string ‘f’. In particular, it does not match the string ‘ff’.

Next: , Previous: , Up: Common Operators   [Contents][Index]

19.3.2 The Match-any-character Operator (.)

This operator matches any single printing or nonprinting character except it won’t match a:

newline

if the syntax bit RE_DOT_NEWLINE isn’t set.

null

if the syntax bit RE_DOT_NOT_NULL is set.

The ‘.’ (period) character represents this operator. For example, ‘a.b’ matches any three-character string beginning with ‘a’ and ending with ‘b’.

Next: , Previous: , Up: Common Operators   [Contents][Index]

19.3.3 The Concatenation Operator

This operator concatenates two regular expressions a and b. No character represents this operator; you simply put b after a. The result is a regular expression that will match a string if a matches its first part and b matches the rest. For example, ‘xy’ (two match-self operators) matches ‘xy’.

Next: , Previous: , Up: Common Operators   [Contents][Index]

19.3.4 Repetition Operators

Repetition operators repeat the preceding regular expression a specified number of times.

Next: , Up: Repetition Operators   [Contents][Index]

19.3.4.1 The Match-zero-or-more Operator (*)

This operator repeats the smallest possible preceding regular expression as many times as necessary (including zero) to match the pattern. ‘*’ represents this operator. For example, ‘o*’ matches any string made up of zero or more ‘o’s. Since this operator operates on the smallest preceding regular expression, ‘fo*’ has a repeating ‘o’, not a repeating ‘fo’. So, ‘fo*’ matches ‘f’, ‘fo’, ‘foo’, and so on.

Since the match-zero-or-more operator is a suffix operator, it may be useless as such when no regular expression precedes it. This is the case when it:

  • is first in a regular expression, or
  • follows a match-beginning-of-line, open-group, or alternation operator.

Three different things can happen in these cases:

  1. If the syntax bit RE_CONTEXT_INVALID_OPS is set, then the regular expression is invalid.
  2. If RE_CONTEXT_INVALID_OPS isn’t set, but RE_CONTEXT_INDEP_OPS is, then ‘*’ represents the match-zero-or-more operator (which then operates on the empty string).
  3. Otherwise, ‘*’ is ordinary.

The matcher processes a match-zero-or-more operator by first matching as many repetitions of the smallest preceding regular expression as it can. Then it continues to match the rest of the pattern.

If it can’t match the rest of the pattern, it backtracks (as many times as necessary), each time discarding one of the matches until it can either match the entire pattern or be certain that it cannot get a match. For example, when matching ‘ca*ar’ against ‘caaar’, the matcher first matches all three ‘a’s of the string with the ‘a*’ of the regular expression. However, it cannot then match the final ‘ar’ of the regular expression against the final ‘r’ of the string. So it backtracks, discarding the match of the last ‘a’ in the string. It can then match the remaining ‘ar’.

Next: , Previous: , Up: Repetition Operators   [Contents][Index]

19.3.4.2 The Match-one-or-more Operator (+ or \+)

If the syntax bit RE_LIMITED_OPS is set, then Regex doesn’t recognize this operator. Otherwise, if the syntax bit RE_BK_PLUS_QM isn’t set, then ‘+’ represents this operator; if it is, then ‘\+’ does.

This operator is similar to the match-zero-or-more operator except that it repeats the preceding regular expression at least once; see The Match-zero-or-more Operator (*), for what it operates on, how some syntax bits affect it, and how Regex backtracks to match it.

For example, supposing that ‘+’ represents the match-one-or-more operator; then ‘ca+r’ matches, e.g., ‘car’ and ‘caaaar’, but not ‘cr’.

Next: , Previous: , Up: Repetition Operators   [Contents][Index]

19.3.4.3 The Match-zero-or-one Operator (? or \?)

If the syntax bit RE_LIMITED_OPS is set, then Regex doesn’t recognize this operator. Otherwise, if the syntax bit RE_BK_PLUS_QM isn’t set, then ‘?’ represents this operator; if it is, then ‘\?’ does.

This operator is similar to the match-zero-or-more operator except that it repeats the preceding regular expression once or not at all; see The Match-zero-or-more Operator (*), to see what it operates on, how some syntax bits affect it, and how Regex backtracks to match it.

For example, supposing that ‘?’ represents the match-zero-or-one operator; then ‘ca?r’ matches both ‘car’ and ‘cr’, but nothing else.

Previous: , Up: Repetition Operators   [Contents][Index]

19.3.4.4 Interval Operators ({ … } or \{ … \})

If the syntax bit RE_INTERVALS is set, then Regex recognizes interval expressions. They repeat the smallest possible preceding regular expression a specified number of times.

If the syntax bit RE_NO_BK_BRACES is set, ‘{’ represents the open-interval operator and ‘}’ represents the close-interval operator ; otherwise, ‘\{’ and ‘\}’ do.

Specifically, supposing that ‘{’ and ‘}’ represent the open-interval and close-interval operators; then:

{count}

matches exactly count occurrences of the preceding regular expression.

{min,}

matches min or more occurrences of the preceding regular expression.

{min, max}

matches at least min but no more than max occurrences of the preceding regular expression.

The interval expression (but not necessarily the regular expression that contains it) is invalid if:

  • min is greater than max, or
  • any of count, min, or max are outside the range zero to RE_DUP_MAX (which symbol regex.h defines).

If the interval expression is invalid and the syntax bit RE_NO_BK_BRACES is set, then Regex considers all the characters in the would-be interval to be ordinary. If that bit isn’t set, then the regular expression is invalid.

If the interval expression is valid but there is no preceding regular expression on which to operate, then if the syntax bit RE_CONTEXT_INVALID_OPS is set, the regular expression is invalid. If that bit isn’t set, then Regex considers all the characters—other than backslashes, which it ignores—in the would-be interval to be ordinary.

Next: , Previous: , Up: Common Operators   [Contents][Index]

19.3.5 The Alternation Operator (| or \|)

If the syntax bit RE_LIMITED_OPS is set, then Regex doesn’t recognize this operator. Otherwise, if the syntax bit RE_NO_BK_VBAR is set, then ‘|’ represents this operator; otherwise, ‘\|’ does.

Alternatives match one of a choice of regular expressions: if you put the character(s) representing the alternation operator between any two regular expressions a and b, the result matches the union of the strings that a and b match. For example, supposing that ‘|’ is the alternation operator, then ‘foo|bar|quux’ would match any of ‘foo’, ‘bar’ or ‘quux’.

The alternation operator operates on the largest possible surrounding regular expressions. (Put another way, it has the lowest precedence of any regular expression operator.) Thus, the only way you can delimit its arguments is to use grouping. For example, if ‘(’ and ‘)’ are the open and close-group operators, then ‘fo(o|b)ar’ would match either ‘fooar’ or ‘fobar’. (‘foo|bar’ would match ‘foo’ or ‘bar’.)

The matcher usually tries all combinations of alternatives so as to match the longest possible string. For example, when matching ‘(fooq|foo)*(qbarquux|bar)’ against ‘fooqbarquux’, it cannot take, say, the first (“depth-first”) combination it could match, since then it would be content to match just ‘fooqbar’.

Note that since the default behavior is to return the leftmost longest match, when more than one of a series of alternatives matches the actual match will be the longest matching alternative, not necessarily the first in the list.

Next: , Previous: , Up: Common Operators   [Contents][Index]

19.3.6 List Operators ([ … ] and [^ … ])

Lists, also called bracket expressions, are a set of one or more items. An item is a character, a collating symbol, an equivalence class expression, a character class expression, or a range expression. The syntax bits affect which kinds of items you can put in a list. We explain the last four items in subsections below. Empty lists are invalid.

A matching list matches a single character represented by one of the list items. You form a matching list by enclosing one or more items within an open-matching-list operator (represented by ‘[’) and a close-list operator (represented by ‘]’).

For example, ‘[ab]’ matches either ‘a’ or ‘b’. ‘[ad]*’ matches the empty string and any string composed of just ‘a’s and ‘d’s in any order. Regex considers invalid a regular expression with a ‘[’ but no matching ‘]’.

Nonmatching lists are similar to matching lists except that they match a single character not represented by one of the list items. You use an open-nonmatching-list operator (represented by ‘[^’4) instead of an open-matching-list operator to start a nonmatching list.

For example, ‘[^ab]’ matches any character except ‘a’ or ‘b’.

If the syntax bit RE_HAT_LISTS_NOT_NEWLINE is set, then nonmatching lists do not match a newline.

Most characters lose any special meaning inside a list. The special characters inside a list follow.

‘]’

ends the list if it’s not the first list item. So, if you want to make the ‘]’ character a list item, you must put it first.

‘\’

quotes the next character if the syntax bit RE_BACKSLASH_ESCAPE_IN_LISTS is set.

‘[.’

represents the open-collating-symbol operator (see Collating Symbol Operators ([. … .])).

‘.]’

represents the close-collating-symbol operator.

‘[=’

represents the open-equivalence-class operator (see Equivalence Class Operators ([= … =])).

‘=]’

represents the close-equivalence-class operator.

‘[:’

represents the open-character-class operator (see Character Class Operators ([: … :])) if the syntax bit RE_CHAR_CLASSES is set and what follows is a valid character class expression.

‘:]’

represents the close-character-class operator if the syntax bit RE_CHAR_CLASSES is set and what precedes it is an open-character-class operator followed by a valid character class name.

‘-’

represents the range operator (see The Range Operator (-)) if it’s not first or last in a list or the ending point of a range.

All other characters are ordinary. For example, ‘[.*]’ matches ‘.’ and ‘*’.

Next: , Up: List Operators ([ … ] and [^ … ])   [Contents][Index]

19.3.6.1 Collating Symbol Operators ([. … .])

Collating symbols can be represented inside lists. You form a collating symbol by putting a collating element between an open-collating-symbol operator and a close-collating-symbol operator. ‘[.’ represents the open-collating-symbol operator and ‘.]’ represents the close-collating-symbol operator. For example, if ‘ll’ is a collating element, then ‘[[.ll.]]’ would match ‘ll’.

Next: , Previous: , Up: List Operators ([ … ] and [^ … ])   [Contents][Index]

19.3.6.2 Equivalence Class Operators ([= … =])

Regex recognizes equivalence class expressions inside lists. A equivalence class expression is a set of collating elements which all belong to the same equivalence class. You form an equivalence class expression by putting a collating element between an open-equivalence-class operator and a close-equivalence-class operator. ‘[=’ represents the open-equivalence-class operator and ‘=]’ represents the close-equivalence-class operator. For example, if ‘a’ and ‘A’ were an equivalence class, then both ‘[[=a=]]’ and ‘[[=A=]]’ would match both ‘a’ and ‘A’. If the collating element in an equivalence class expression isn’t part of an equivalence class, then the matcher considers the equivalence class expression to be a collating symbol.

Next: , Previous: , Up: List Operators ([ … ] and [^ … ])   [Contents][Index]

19.3.6.3 Character Class Operators ([: … :])

If the syntax bit RE_CHAR_CLASSES is set, then Regex recognizes character class expressions inside lists. A character class expression matches one character from a given class. You form a character class expression by putting a character class name between an open-character-class operator (represented by ‘[:’) and a close-character-class operator (represented by ‘:]’). The character class names and their meanings are:

alnum

letters and digits

alpha

letters

blank

system-dependent; for GNU, a space or tab

cntrl

control characters (in the ASCII encoding, code 0177 and codes less than 040)

digit

digits

graph

same as print except omits space

lower

lowercase letters

print

printable characters (in the ASCII encoding, space tilde—codes 040 through 0176)

punct

neither control nor alphanumeric characters

space

space, carriage return, newline, vertical tab, and form feed

upper

uppercase letters

xdigit

hexadecimal digits: 0–9, a–f, A–F

These correspond to the definitions in the C library’s <ctype.h> facility. For example, ‘[:alpha:]’ corresponds to the standard facility isalpha. Regex recognizes character class expressions only inside of lists; so ‘[[:alpha:]]’ matches any letter, but ‘[:alpha:]’ outside of a bracket expression and not followed by a repetition operator matches just itself.

Previous: , Up: List Operators ([ … ] and [^ … ])   [Contents][Index]

19.3.6.4 The Range Operator (-)

Regex recognizes range expressions inside a list. They represent those characters that fall between two elements in the current collating sequence. You form a range expression by putting a range operator between two of any of the following: characters, collating elements, collating symbols, and equivalence class expressions. The starting point of the range and the ending point of the range don’t have to be the same kind of item, e.g., the starting point could be a collating element and the ending point could be an equivalence class expression. If a range’s ending point is an equivalence class, then all the collating elements in that class will be in the range.5 ‘-’ represents the range operator. For example, ‘a-f’ within a list represents all the characters from ‘a’ through ‘f’ inclusively.

If the syntax bit RE_NO_EMPTY_RANGES is set, then if the range’s ending point collates less than its starting point, the range (and the regular expression containing it) is invalid. For example, the regular expression ‘[z-a]’ would be invalid. If this bit isn’t set, then Regex considers such a range to be empty.

Since ‘-’ represents the range operator, if you want to make a ‘-’ character itself a list item, you must do one of the following:

  • Put the ‘-’ either first or last in the list.
  • Include a range whose starting point collates strictly lower than ‘-’ and whose ending point collates equal or higher. Unless a range is the first item in a list, a ‘-’ can’t be its starting point, but can be its ending point. That is because Regex considers ‘-’ to be the range operator unless it is preceded by another ‘-’. For example, in the ASCII encoding, ‘)’, ‘*’, ‘+’, ‘,’, ‘-’, ‘.’, and ‘/’ are contiguous characters in the collating sequence. You might think that ‘[)-+--/]’ has two ranges: ‘)-+’ and ‘--/’. Rather, it has the ranges ‘)-+’ and ‘+--’, plus the character ‘/’, so it matches, e.g., ‘,’, not ‘.’.
  • Put a range whose starting point is ‘-’ first in the list.

For example, ‘[-a-z]’ matches a lowercase letter or a hyphen (in English, in ASCII).

Next: , Previous: , Up: Common Operators   [Contents][Index]

19.3.7 Grouping Operators (( … ) or \( … \))

A group, also known as a subexpression, consists of an open-group operator, any number of other operators, and a close-group operator. Regex treats this sequence as a unit, just as mathematics and programming languages treat a parenthesized expression as a unit.

Therefore, using groups, you can:

If the syntax bit RE_NO_BK_PARENS is set, then ‘(’ represents the open-group operator and ‘)’ represents the close-group operator; otherwise, ‘\(’ and ‘\)’ do.

If the syntax bit RE_UNMATCHED_RIGHT_PAREN_ORD is set and a close-group operator has no matching open-group operator, then Regex considers it to match ‘)’.

Next: , Previous: , Up: Common Operators   [Contents][Index]

19.3.8 The Back-reference Operator (\digit)

If the syntax bit RE_NO_BK_REF isn’t set, then Regex recognizes back-references. A back-reference matches a specified preceding group. The back-reference operator is represented by ‘\digit’ anywhere after the end of a regular expression’s digit-th group (see Grouping Operators (( … ) or \( … \))).

digit must be between ‘1’ and ‘9’. The matcher assigns numbers 1 through 9 to the first nine groups it encounters. By using one of ‘\1’ through ‘\9’ after the corresponding group’s close-group operator, you can match a substring identical to the one that the group does.

Back-references match according to the following (in all examples below, ‘(’ represents the open-group, ‘)’ the close-group, ‘{’ the open-interval and ‘}’ the close-interval operator):

  • If the group matches a substring, the back-reference matches an identical substring. For example, ‘(a)\1’ matches ‘aa’ and ‘(bana)na\1bo\1’ matches ‘bananabanabobana’. Likewise, ‘(.*)\1’ matches any (newline-free if the syntax bit RE_DOT_NEWLINE isn’t set) string that is composed of two identical halves; the ‘(.*)’ matches the first half and the ‘\1’ matches the second half.
  • If the group matches more than once (as it might if followed by, e.g., a repetition operator), then the back-reference matches the substring the group last matched. For example, ‘((a*)b)*\1\2’ matches ‘aabababa’; first group 1 (the outer one) matches ‘aab’ and group 2 (the inner one) matches ‘aa’. Then group 1 matches ‘ab’ and group 2 matches ‘a’. So, ‘\1’ matches ‘ab’ and ‘\2’ matches ‘a’.
  • If the group doesn’t participate in a match, i.e., it is part of an alternative not taken or a repetition operator allows zero repetitions of it, then the back-reference makes the whole match fail. For example, ‘(one()|two())-and-(three\2|four\3)’ matches ‘one-and-three’ and ‘two-and-four’, but not ‘one-and-four’ or ‘two-and-three’. For example, if the pattern matches ‘one-and-’, then its group 2 matches the empty string and its group 3 doesn’t participate in the match. So, if it then matches ‘four’, then when it tries to back-reference group 3—which it will attempt to do because ‘\3’ follows the ‘four’—the match will fail because group 3 didn’t participate in the match.

You can use a back-reference as an argument to a repetition operator. For example, ‘(a(b))\2*’ matches ‘a’ followed by two or more ‘b’s. Similarly, ‘(a(b))\2{3}’ matches ‘abbbb’.

If there is no preceding digit-th subexpression, the regular expression is invalid.

Back-references can greatly slow down matching, as they can generate exponentially many matching possibilities that can consume both time and memory to explore. Also, the POSIX specification for back-references is at times unclear. Furthermore, many regular expression implementations have back-reference bugs that can cause programs to return incorrect answers or even crash, and fixing these bugs has often been low-priority: for example, as of 2020 the GNU C library bug database contained back-reference bugs 52, 10844, 11053, 24269 and 25322, with little sign of forthcoming fixes. Luckily, back-references are rarely useful and it should be little trouble to avoid them in practical applications.

Previous: , Up: Common Operators   [Contents][Index]

19.3.9 Anchoring Operators

These operators can constrain a pattern to match only at the beginning or end of the entire string or at the beginning or end of a line.

Next: , Up: Anchoring Operators   [Contents][Index]

19.3.9.1 The Match-beginning-of-line Operator (^)

This operator can match the empty string either at the beginning of the string or after a newline character. Thus, it is said to anchor the pattern to the beginning of a line.

In the cases following, ‘^’ represents this operator. (Otherwise, ‘^’ is ordinary.)

These rules imply that some valid patterns containing ‘^’ cannot be matched; for example, ‘foo^bar’ if RE_CONTEXT_INDEP_ANCHORS is set.

If the not_bol field is set in the pattern buffer (see GNU Pattern Buffers), then ‘^’ fails to match at the beginning of the string. This lets you match against pieces of a line, as you would need to if, say, searching for repeated instances of a given pattern in a line; it would work correctly for patterns both with and without match-beginning-of-line operators.

Previous: , Up: Anchoring Operators   [Contents][Index]

19.3.9.2 The Match-end-of-line Operator ($)

This operator can match the empty string either at the end of the string or before a newline character in the string. Thus, it is said to anchor the pattern to the end of a line.

It is always represented by ‘$’. For example, ‘foo$’ usually matches, e.g., ‘foo’ and, e.g., the first three characters of ‘foo\nbar’.

Its interaction with the syntax bits and pattern buffer fields is exactly the dual of ‘^’’s; see the previous section. (That is, “‘^’” becomes “‘$’”, “beginning” becomes “end”, “next” becomes “previous”, “after” becomes “before”, and “not_bol” becomes “not_eol”.)

Next: , Previous: , Up: Regular expressions   [Contents][Index]

19.4 GNU Operators

The following are operators that GNU defines (and POSIX doesn’t) that you can use unless the syntax bit RE_NO_GNU_OPS is set.

Next: , Up: GNU Operators   [Contents][Index]

19.4.1 Word Operators

The operators in this section require Regex to recognize parts of words. Characters that are part of words, which are called word-constituent, are letters, digits, and the underscore (‘_’); more precisely, any character in the POSIX class alnum in the current locale, or underscore.

Next: , Up: Word Operators   [Contents][Index]

19.4.1.1 The Match-word-boundary Operator (\b)

This operator (represented by ‘\b’) matches the empty string at either the beginning or the end of a word. For example, ‘\brat\b’ matches the separate word ‘rat’.

Next: , Previous: , Up: Word Operators   [Contents][Index]

19.4.1.2 The Match-within-word Operator (\B)

This operator (represented by ‘\B’) matches the empty string within a word. For example, ‘c\Brat\Be’ matches ‘crate’, but ‘dirty \Brat’ doesn’t match ‘dirty rat’.

Next: , Previous: , Up: Word Operators   [Contents][Index]

19.4.1.3 The Match-beginning-of-word Operator (\<)

This operator (represented by ‘\<’) matches the empty string at the beginning of a word.

Next: , Previous: , Up: Word Operators   [Contents][Index]

19.4.1.4 The Match-end-of-word Operator (\>)

This operator (represented by ‘\>’) matches the empty string at the end of a word.

Next: , Previous: , Up: Word Operators   [Contents][Index]

19.4.1.5 The Match-word-constituent Operator (\w)

This operator (represented by ‘\w’) matches any word-constituent character.

Previous: , Up: Word Operators   [Contents][Index]

19.4.1.6 The Match-non-word-constituent Operator (\W)

This operator (represented by ‘\W’) matches any character that is not word-constituent.

Next: , Previous: , Up: GNU Operators   [Contents][Index]

19.4.2 Space Operators

Next: , Up: Space Operators   [Contents][Index]

19.4.2.1 The Match-space Operator (\s)

This operator (represented by ‘\s’) matches any space character (that is, in the POSIX class [:space:]).

Previous: , Up: Space Operators   [Contents][Index]

19.4.2.2 The Match-non-space Operator (\S)

This operator (represented by ‘\S’) matches any character that is not a space (that is, in the POSIX class [:space:]).

Previous: , Up: GNU Operators   [Contents][Index]

19.4.3 Whole-string Operators

Following are operators which work on the whole string.

Next: , Up: Whole-string Operators   [Contents][Index]

19.4.3.1 The Match-beginning-of-string Operator (\`)

This operator (represented by ‘\`’) matches the empty string at the beginning of the string.

Previous: , Up: Whole-string Operators   [Contents][Index]

19.4.3.2 The Match-end-of-string Operator (\')

This operator (represented by ‘\'’) matches the empty string at the end of the string.

Next: , Previous: , Up: Regular expressions   [Contents][Index]

19.5 What Gets Matched?

Regex usually matches strings according to the “leftmost longest” rule; that is, it chooses the longest of the leftmost matches. This does not mean that for a regular expression containing subexpressions that it simply chooses the longest match for each subexpression, left to right; the overall match must also be the longest possible one.

For example, ‘(ac*)(c*d[ac]*)\1’ matches ‘acdacaaa’, not ‘acdac’, as it would if it were to choose the longest match for the first subexpression.

Next: , Previous: , Up: Regular expressions   [Contents][Index]

19.6 Programming with Regex

Here we describe how you use the Regex data structures and functions in C programs. Regex has three interfaces: one designed for GNU, one compatible with POSIX (as specified by POSIX, draft 1003.2/D11.2), and one compatible with Berkeley Unix. The POSIX interface is not documented here; see the documentation of GNU libc, or the POSIX man pages. The Berkeley Unix interface is documented here for convenience, since its documentation is not otherwise readily available on GNU systems.

Next: , Up: Programming with Regex   [Contents][Index]

19.6.1 GNU Regex Functions

If you’re writing code that doesn’t need to be compatible with either POSIX or Berkeley Unix, you can use these functions. They provide more options than the other interfaces.

Next: , Up: GNU Regex Functions   [Contents][Index]

19.6.1.1 GNU Pattern Buffers

To compile, match, or search for a given regular expression, you must supply a pattern buffer. A pattern buffer holds one compiled regular expression.6

You can have several different pattern buffers simultaneously, each holding a compiled pattern for a different regular expression.

regex.h defines the pattern buffer struct with the following public fields: 

  unsigned char *buffer;
  unsigned long allocated;
  char *fastmap;
  char *translate;
  size_t re_nsub;
  unsigned no_sub : 1;
  unsigned not_bol : 1;
  unsigned not_eol : 1;

Next: , Previous: , Up: GNU Regex Functions   [Contents][Index]

19.6.1.2 GNU Regular Expression Compiling

In GNU, you can both match and search for a given regular expression. To do either, you must first compile it in a pattern buffer (see GNU Pattern Buffers).

Regular expressions match according to the syntax with which they were compiled; with GNU, you indicate what syntax you want by setting the variable re_syntax_options (declared in regex.h) before calling the compiling function, re_compile_pattern (see below). See Syntax Bits, and Predefined Syntaxes.

You can change the value of re_syntax_options at any time. Usually, however, you set its value once and then never change it.

re_compile_pattern takes a pattern buffer as an argument. You must initialize the following fields:

translate initialization
translate

Initialize this to point to a translate table if you want one, or to zero if you don’t. We explain translate tables in GNU Translate Tables.

fastmap

Initialize this to nonzero if you want a fastmap, or to zero if you don’t.

buffer
allocated

If you want re_compile_pattern to allocate memory for the compiled pattern, set both of these to zero. If you have an existing block of memory (allocated with malloc) you want Regex to use, set buffer to its address and allocated to its size (in bytes).

re_compile_pattern uses realloc to extend the space for the compiled pattern as necessary.

To compile a pattern buffer, use: 

char *
re_compile_pattern (const char *regex, const int regex_size,
                    struct re_pattern_buffer *pattern_buffer)

regex is the regular expression’s address, regex_size is its length, and pattern_buffer is the pattern buffer’s address.

If re_compile_pattern successfully compiles the regular expression, it returns zero and sets *pattern_buffer to the compiled pattern. It sets the pattern buffer’s fields as follows:

buffer

to the compiled pattern.

syntax

to the current value of re_syntax_options.

re_nsub

to the number of subexpressions in regex.

If re_compile_pattern can’t compile regex, it returns an error string corresponding to a POSIX error code.

Next: , Previous: , Up: GNU Regex Functions   [Contents][Index]

19.6.1.3 GNU Matching

Matching the GNU way means trying to match as much of a string as possible starting at a position within it you specify. Once you’ve compiled a pattern into a pattern buffer (see GNU Regular Expression Compiling), you can ask the matcher to match that pattern against a string using: 

int
re_match (struct re_pattern_buffer *pattern_buffer,
          const char *string, const int size,
          const int start, struct re_registers *regs)

pattern_buffer is the address of a pattern buffer containing a compiled pattern. string is the string you want to match; it can contain newline and null characters. size is the length of that string. start is the string index at which you want to begin matching; the first character of string is at index zero. See Using Registers, for an explanation of regs; you can safely pass zero.

re_match matches the regular expression in pattern_buffer against the string string according to the syntax of pattern_buffer. (See GNU Regular Expression Compiling, for how to set it.) The function returns -1 if the compiled pattern does not match any part of string and -2 if an internal error happens; otherwise, it returns how many (possibly zero) characters of string the pattern matched.

An example: suppose pattern_buffer points to a pattern buffer containing the compiled pattern for ‘a*’, and string points to ‘aaaaab’ (whereupon size should be 6). Then if start is 2, re_match returns 3, i.e., ‘a*’ would have matched the last three ‘a’s in string. If start is 0, re_match returns 5, i.e., ‘a*’ would have matched all the ‘a’s in string. If start is either 5 or 6, it returns zero.

If start is not between zero and size, then re_match returns -1.

Next: , Previous: , Up: GNU Regex Functions   [Contents][Index]

19.6.1.4 GNU Searching

Searching means trying to match starting at successive positions within a string. The function re_search does this.

Before calling re_search, you must compile your regular expression. See GNU Regular Expression Compiling.

Here is the function declaration: 

int
re_search (struct re_pattern_buffer *pattern_buffer,
           const char *string, const int size,
           const int start, const int range,
           struct re_registers *regs)

whose arguments are the same as those to re_match (see GNU Matching) except that the two arguments start and range replace re_match’s argument start.

If range is positive, then re_search attempts a match starting first at index start, then at start + 1 if that fails, and so on, up to start + range; if range is negative, then it attempts a match starting first at index start, then at start -1 if that fails, and so on.

If start is not between zero and size, then re_search returns -1. When range is positive, re_search adjusts range so that start + range - 1 is between zero and size, if necessary; that way it won’t search outside of string. Similarly, when range is negative, re_search adjusts range so that start + range + 1 is between zero and size, if necessary.

If the fastmap field of pattern_buffer is zero, re_search matches starting at consecutive positions; otherwise, it uses fastmap to make the search more efficient. See Searching with Fastmaps.

If no match is found, re_search returns -1. If a match is found, it returns the index where the match began. If an internal error happens, it returns -2.

Next: , Previous: , Up: GNU Regex Functions   [Contents][Index]

19.6.1.5 Matching and Searching with Split Data

Using the functions re_match_2 and re_search_2, you can match or search in data that is divided into two strings.

The function: 

int
re_match_2 (struct re_pattern_buffer *buffer,
            const char *string1, const int size1,
            const char *string2, const int size2,
            const int start,
            struct re_registers *regs,
            const int stop)

is similar to re_match (see GNU Matching) except that you pass two data strings and sizes, and an index stop beyond which you don’t want the matcher to try matching. As with re_match, if it succeeds, re_match_2 returns how many characters of string it matched. Regard string1 and string2 as concatenated when you set the arguments start and stop and use the contents of regs; re_match_2 never returns a value larger than size1 + size2.

The function: 

int
re_search_2 (struct re_pattern_buffer *buffer,
             const char *string1, const int size1,
             const char *string2, const int size2,
             const int start, const int range,
             struct re_registers *regs,
             const int stop)

is similarly related to re_search.

Next: , Previous: , Up: GNU Regex Functions   [Contents][Index]

19.6.1.6 Searching with Fastmaps

If you’re searching through a long string, you should use a fastmap. Without one, the searcher tries to match at consecutive positions in the string. Generally, most of the characters in the string could not start a match. It takes much longer to try matching at a given position in the string than it does to check in a table whether or not the character at that position could start a match. A fastmap is such a table.

More specifically, a fastmap is an array indexed by the characters in your character set. Under the ASCII encoding, therefore, a fastmap has 256 elements. If you want the searcher to use a fastmap with a given pattern buffer, you must allocate the array and assign the array’s address to the pattern buffer’s fastmap field. You either can compile the fastmap yourself or have re_search do it for you; when fastmap is nonzero, it automatically compiles a fastmap the first time you search using a particular compiled pattern.

By setting the buffer’s fastmap field before calling re_compile_pattern, you can reuse a buffer data structure across multiple searches with different patterns, and allocate the fastmap only once. Nonetheless, the fastmap must be recompiled each time the buffer has a new pattern compiled into it.

To compile a fastmap yourself, use: 

int
re_compile_fastmap (struct re_pattern_buffer *pattern_buffer)

pattern_buffer is the address of a pattern buffer. If the character c could start a match for the pattern, re_compile_fastmap makes pattern_buffer->fastmap[c] nonzero. It returns 0 if it can compile a fastmap and -2 if there is an internal error. For example, if ‘|’ is the alternation operator and pattern_buffer holds the compiled pattern for ‘a|b’, then re_compile_fastmap sets fastmap['a'] and fastmap['b'] (and no others).

re_search uses a fastmap as it moves along in the string: it checks the string’s characters until it finds one that’s in the fastmap. Then it tries matching at that character. If the match fails, it repeats the process. So, by using a fastmap, re_search doesn’t waste time trying to match at positions in the string that couldn’t start a match.

If you don’t want re_search to use a fastmap, store zero in the fastmap field of the pattern buffer before calling re_search.

Once you’ve initialized a pattern buffer’s fastmap field, you need never do so again—even if you compile a new pattern in it—provided the way the field is set still reflects whether or not you want a fastmap. re_search will still either do nothing if fastmap is null or, if it isn’t, compile a new fastmap for the new pattern.

Next: , Previous: , Up: GNU Regex Functions   [Contents][Index]

19.6.1.7 GNU Translate Tables

If you set the translate field of a pattern buffer to a translate table, then the GNU Regex functions to which you’ve passed that pattern buffer use it to apply a simple transformation to all the regular expression and string characters at which they look.

A translate table is an array indexed by the characters in your character set. Under the ASCII encoding, therefore, a translate table has 256 elements. The array’s elements are also characters in your character set. When the Regex functions see a character c, they use translate[c] in its place, with one exception: the character after a ‘\’ is not translated. (This ensures that, the operators, e.g., ‘\B’ and ‘\b’, are always distinguishable.)

For example, a table that maps all lowercase letters to the corresponding uppercase ones would cause the matcher to ignore differences in case.7 Such a table would map all characters except lowercase letters to themselves, and lowercase letters to the corresponding uppercase ones. Under the ASCII encoding, here’s how you could initialize such a table (we’ll call it case_fold): 

for (i = 0; i < 256; i++)
  case_fold[i] = i;
for (i = 'a'; i <= 'z'; i++)
  case_fold[i] = i - ('a' - 'A');

You tell Regex to use a translate table on a given pattern buffer by assigning that table’s address to the translate field of that buffer. If you don’t want Regex to do any translation, put zero into this field. You’ll get weird results if you change the table’s contents anytime between compiling the pattern buffer, compiling its fastmap, and matching or searching with the pattern buffer.

Next: , Previous: , Up: GNU Regex Functions   [Contents][Index]

19.6.1.8 Using Registers

A group in a regular expression can match a (possibly empty) substring of the string that regular expression as a whole matched. The matcher remembers the beginning and end of the substring matched by each group.

To find out what they matched, pass a nonzero regs argument to a GNU matching or searching function (see GNU Matching and GNU Searching), i.e., the address of a structure of this type, as defined in regex.h: 

struct re_registers
{
  unsigned num_regs;
  regoff_t *start;
  regoff_t *end;
};

Except for (possibly) the num_regs’th element (see below), the ith element of the start and end arrays records information about the ith group in the pattern. (They’re declared as C pointers, but this is only because not all C compilers accept zero-length arrays; conceptually, it is simplest to think of them as arrays.)

The start and end arrays are allocated in one of two ways. The simplest and perhaps most useful is to let the matcher (re)allocate enough space to record information for all the groups in the regular expression. If re_set_registers is not called before searching or matching, then the matcher allocates two arrays each of 1 + re_nsub elements (re_nsub is another field in the pattern buffer; see GNU Pattern Buffers). The extra element is set to -1. Then on subsequent calls with the same pattern buffer and regs arguments, the matcher reallocates more space if necessary.

The function: 

void
re_set_registers (struct re_pattern_buffer *buffer,
                  struct re_registers *regs,
                  size_t num_regs,
                  regoff_t *starts, regoff_t *ends)

sets regs to hold num_regs registers, storing them in starts and ends. Subsequent matches using buffer and regs will use this memory for recording register information. starts and ends must be allocated with malloc, and must each be at least num_regs * sizeof (regoff_t) bytes long.

If num_regs is zero, then subsequent matches should allocate their own register data.

Unless this function is called, the first search or match using buffer will allocate its own register data, without freeing the old data.

The following examples illustrate the information recorded in the re_registers structure. (In all of them, ‘(’ represents the open-group and ‘)’ the close-group operator. The first character in the string string is at index 0.)

  • If the regular expression has an i-th group that matches a substring of string, then the function sets regs->start[i] to the index in string where the substring matched by the i-th group begins, and regs->end[i] to the index just beyond that substring’s end. The function sets regs->start[0] and regs->end[0] to analogous information about the entire pattern.

    For example, when you match ‘((a)(b))’ against ‘ab’, you get:

    • 0 in regs->start[0] and 2 in regs->end[0]
    • 0 in regs->start[1] and 2 in regs->end[1]
    • 0 in regs->start[2] and 1 in regs->end[2]
    • 1 in regs->start[3] and 2 in regs->end[3]
  • If a group matches more than once (as it might if followed by, e.g., a repetition operator), then the function reports the information about what the group last matched.

    For example, when you match the pattern ‘(a)*’ against the string ‘aa’, you get:

    • 0 in regs->start[0] and 2 in regs->end[0]
    • 1 in regs->start[1] and 2 in regs->end[1]
  • If the i-th group does not participate in a successful match, e.g., it is an alternative not taken or a repetition operator allows zero repetitions of it, then the function sets regs->start[i] and regs->end[i] to -1.

    For example, when you match the pattern ‘(a)*b’ against the string ‘b’, you get:

    • 0 in regs->start[0] and 1 in regs->end[0]
    • -1 in regs->start[1] and -1 in regs->end[1]
  • If the i-th group matches a zero-length string, then the function sets regs->start[i] and regs->end[i] to the index just beyond that zero-length string.

    For example, when you match the pattern ‘(a*)b’ against the string ‘b’, you get:

    • 0 in regs->start[0] and 1 in regs->end[0]
    • 0 in regs->start[1] and 0 in regs->end[1]
  • If an i-th group contains a j-th group in turn not contained within any other group within group i and the function reports a match of the i-th group, then it records in regs->start[j] and regs->end[j] the last match (if it matched) of the j-th group.

    For example, when you match the pattern ‘((a*)b)*’ against the string ‘abb’, group 2 last matches the empty string, so you get what it previously matched:

    • 0 in regs->start[0] and 3 in regs->end[0]
    • 2 in regs->start[1] and 3 in regs->end[1]
    • 2 in regs->start[2] and 2 in regs->end[2]

    When you match the pattern ‘((a)*b)*’ against the string ‘abb’, group 2 doesn’t participate in the last match, so you get:

    • 0 in regs->start[0] and 3 in regs->end[0]
    • 2 in regs->start[1] and 3 in regs->end[1]
    • 0 in regs->start[2] and 1 in regs->end[2]
  • If an i-th group contains a j-th group in turn not contained within any other group within group i and the function sets regs->start[i] and regs->end[i] to -1, then it also sets regs->start[j] and regs->end[j] to -1.

    For example, when you match the pattern ‘((a)*b)*c’ against the string ‘c’, you get:

    • 0 in regs->start[0] and 1 in regs->end[0]
    • -1 in regs->start[1] and -1 in regs->end[1]
    • -1 in regs->start[2] and -1 in regs->end[2]

Previous: , Up: GNU Regex Functions   [Contents][Index]

19.6.1.9 Freeing GNU Pattern Buffers

To free any allocated fields of a pattern buffer, use the POSIX function regfree: 

void
regfree (regex_t *preg)

preg is the pattern buffer whose allocated fields you want freed; this works because since the type regex_t—the type for POSIX pattern buffers—is equivalent to the type re_pattern_buffer.

regfree also sets preg’s allocated field to zero. After a buffer has been freed, it must have a regular expression compiled in it before passing it to a matching or searching function.

Previous: , Up: Programming with Regex   [Contents][Index]

19.6.2 BSD Regex Functions

If you’re writing code that has to be Berkeley Unix compatible, you’ll need to use these functions whose interfaces are the same as those in Berkeley Unix.

Next: , Up: BSD Regex Functions   [Contents][Index]

19.6.2.1 BSD Regular Expression Compiling

With Berkeley Unix, you can only search for a given regular expression; you can’t match one. To search for it, you must first compile it. Before you compile it, you must indicate the regular expression syntax you want it compiled according to by setting the variable re_syntax_options (declared in regex.h) to some syntax (see Regular Expression Syntax).

To compile a regular expression use: 

char *
re_comp (char *regex)

regex is the address of a null-terminated regular expression. re_comp uses an internal pattern buffer, so you can use only the most recently compiled pattern buffer. This means that if you want to use a given regular expression that you’ve already compiled—but it isn’t the latest one you’ve compiled—you’ll have to recompile it. If you call re_comp with the null string (not the empty string) as the argument, it doesn’t change the contents of the pattern buffer.

If re_comp successfully compiles the regular expression, it returns zero. If it can’t compile the regular expression, it returns an error string. re_comp’s error messages are identical to those of re_compile_pattern (see GNU Regular Expression Compiling).

Previous: , Up: BSD Regex Functions   [Contents][Index]

19.6.2.2 BSD Searching

Searching the Berkeley Unix way means searching in a string starting at its first character and trying successive positions within it to find a match. Once you’ve compiled a pattern using re_comp (see BSD Regular Expression Compiling), you can ask Regex to search for that pattern in a string using: 

int
re_exec (char *string)

string is the address of the null-terminated string in which you want to search.

re_exec returns either 1 for success or 0 for failure. It automatically uses a GNU fastmap (see Searching with Fastmaps).

Previous: , Up: Regular expressions   [Contents][Index]

19.7 Regular expression syntaxes

Gnulib supports many different types of regular expressions; although the underlying features are the same or identical, the syntax used varies. The descriptions given here for the different types are generated automatically.

Next: , Up: Regular expression syntaxes   [Contents][Index]

19.7.1 ‘awk’ regular expression syntax

The character ‘.’ matches any single character except the null character.

‘+’

indicates that the regular expression should match one or more occurrences of the previous atom or regexp.

‘?’

indicates that the regular expression should match zero or one occurrence of the previous atom or regexp.

‘\+’

matches a ‘+’

‘\?’

matches a ‘?’.

Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example ‘[z-a]’, are invalid. Within square brackets, ‘\’ can be used to quote the following character. Character classes are supported; for example ‘[[:digit:]]’ will match a single decimal digit.

GNU extensions are not supported and so ‘\w’, ‘\W’, ‘\<’, ‘\>’, ‘\b’, ‘\B’, ‘\`’, and ‘\'’ match ‘w’, ‘W’, ‘<’, ‘>’, ‘b’, ‘B’, ‘`’, and ‘'’ respectively.

Grouping is performed with parentheses ‘()’. An unmatched ‘)’ matches just itself. A backslash followed by a digit matches that digit.

The alternation operator is ‘|’.

The characters ‘^’ and ‘$’ always represent the beginning and end of a string respectively, except within square brackets. Within brackets, ‘^’ can be used to invert the membership of the character class being specified.

‘*’, ‘+’ and ‘?’ are special at any point in a regular expression except:

  1. At the beginning of a regular expression
  2. After an open-group, signified by ‘(’
  3. After the alternation operator ‘|’

The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups.

Next: , Previous: , Up: Regular expression syntaxes   [Contents][Index]

19.7.2 ‘ed’ regular expression syntax

The character ‘.’ matches any single character except the null character.

‘\+’

indicates that the regular expression should match one or more occurrences of the previous atom or regexp.

‘\?’

indicates that the regular expression should match zero or one occurrence of the previous atom or regexp.

‘+ and ?’

match themselves.

Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example ‘[z-a]’, are invalid. Within square brackets, ‘\’ is taken literally. Character classes are supported; for example ‘[[:digit:]]’ will match a single decimal digit.

GNU extensions are supported:

  1. ‘\w’ matches a character within a word
  2. ‘\W’ matches a character which is not within a word
  3. ‘\<’ matches the beginning of a word
  4. ‘\>’ matches the end of a word
  5. ‘\b’ matches a word boundary
  6. ‘\B’ matches characters which are not a word boundary
  7. ‘\`’ matches the beginning of the whole input
  8. ‘\'’ matches the end of the whole input

Grouping is performed with backslashes followed by parentheses ‘\(’, ‘\)’. A backslash followed by a digit acts as a back-reference and matches the same thing as the previous grouped expression indicated by that number. For example ‘\2’ matches the second group expression. The order of group expressions is determined by the position of their opening parenthesis ‘\(’.

The alternation operator is ‘\|’.

The character ‘^’ only represents the beginning of a string when it appears:

  1. At the beginning of a regular expression
  2. After an open-group, signified by ‘\(’
  3. After the alternation operator ‘\|’

The character ‘$’ only represents the end of a string when it appears:

  1. At the end of a regular expression
  2. Before a close-group, signified by ‘\)’
  3. Before the alternation operator ‘\|’

‘\*’, ‘\+’ and ‘\?’ are special at any point in a regular expression except:

  1. At the beginning of a regular expression
  2. After an open-group, signified by ‘\(’
  3. After the alternation operator ‘\|’

Intervals are specified by ‘\{’ and ‘\}’. Invalid intervals such as ‘a\{1z’ are not accepted.

The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups.

Next: , Previous: , Up: Regular expression syntaxes   [Contents][Index]

19.7.3 ‘egrep’ regular expression syntax

The character ‘.’ matches any single character.

‘+’

indicates that the regular expression should match one or more occurrences of the previous atom or regexp.

‘?’

indicates that the regular expression should match zero or one occurrence of the previous atom or regexp.

‘\+’

matches a ‘+’

‘\?’

matches a ‘?’.

Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example ‘[z-a]’, are invalid. Within square brackets, ‘\’ is taken literally. Character classes are supported; for example ‘[[:digit:]]’ will match a single decimal digit.

GNU extensions are supported:

  1. ‘\w’ matches a character within a word
  2. ‘\W’ matches a character which is not within a word
  3. ‘\<’ matches the beginning of a word
  4. ‘\>’ matches the end of a word
  5. ‘\b’ matches a word boundary
  6. ‘\B’ matches characters which are not a word boundary
  7. ‘\`’ matches the beginning of the whole input
  8. ‘\'’ matches the end of the whole input

Grouping is performed with parentheses ‘()’. An unmatched ‘)’ matches just itself. A backslash followed by a digit acts as a back-reference and matches the same thing as the previous grouped expression indicated by that number. For example ‘\2’ matches the second group expression. The order of group expressions is determined by the position of their opening parenthesis ‘(’.

The alternation operator is ‘|’.

The characters ‘^’ and ‘$’ always represent the beginning and end of a string respectively, except within square brackets. Within brackets, ‘^’ can be used to invert the membership of the character class being specified.

The characters ‘*’, ‘+’ and ‘?’ are special anywhere in a regular expression.

Intervals are specified by ‘{’ and ‘}’. Invalid intervals are treated as literals, for example ‘a{1’ is treated as ‘a\{1’

The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups.

Next: , Previous: , Up: Regular expression syntaxes   [Contents][Index]

19.7.4 ‘emacs’ regular expression syntax

The character ‘.’ matches any single character except newline.

‘+’

indicates that the regular expression should match one or more occurrences of the previous atom or regexp.

‘?’

indicates that the regular expression should match zero or one occurrence of the previous atom or regexp.

‘\+’

matches a ‘+’

‘\?’

matches a ‘?’.

Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example ‘[z-a]’, are ignored. Within square brackets, ‘\’ is taken literally. Character classes are supported; for example ‘[[:digit:]]’ will match a single decimal digit.

GNU extensions are supported:

  1. ‘\w’ matches a character within a word
  2. ‘\W’ matches a character which is not within a word
  3. ‘\<’ matches the beginning of a word
  4. ‘\>’ matches the end of a word
  5. ‘\b’ matches a word boundary
  6. ‘\B’ matches characters which are not a word boundary
  7. ‘\`’ matches the beginning of the whole input
  8. ‘\'’ matches the end of the whole input

Grouping is performed with backslashes followed by parentheses ‘\(’, ‘\)’. A backslash followed by a digit acts as a back-reference and matches the same thing as the previous grouped expression indicated by that number. For example ‘\2’ matches the second group expression. The order of group expressions is determined by the position of their opening parenthesis ‘\(’.

The alternation operator is ‘\|’.

The character ‘^’ only represents the beginning of a string when it appears:

  1. At the beginning of a regular expression
  2. After an open-group, signified by ‘\(’
  3. After the alternation operator ‘\|’

The character ‘$’ only represents the end of a string when it appears:

  1. At the end of a regular expression
  2. Before a close-group, signified by ‘\)’
  3. Before the alternation operator ‘\|’

‘*’, ‘+’ and ‘?’ are special at any point in a regular expression except:

  1. At the beginning of a regular expression
  2. After an open-group, signified by ‘\(’
  3. After the alternation operator ‘\|’

Intervals are specified by ‘\{’ and ‘\}’. Invalid intervals such as ‘a\{1z’ are not accepted.

The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups.

Next: , Previous: , Up: Regular expression syntaxes   [Contents][Index]

19.7.5 ‘gnu-awk’ regular expression syntax

The character ‘.’ matches any single character.

‘+’

indicates that the regular expression should match one or more occurrences of the previous atom or regexp.

‘?’

indicates that the regular expression should match zero or one occurrence of the previous atom or regexp.

‘\+’

matches a ‘+’

‘\?’

matches a ‘?’.

Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example ‘[z-a]’, are invalid. Within square brackets, ‘\’ can be used to quote the following character. Character classes are supported; for example ‘[[:digit:]]’ will match a single decimal digit.

GNU extensions are supported:

  1. ‘\w’ matches a character within a word
  2. ‘\W’ matches a character which is not within a word
  3. ‘\<’ matches the beginning of a word
  4. ‘\>’ matches the end of a word
  5. ‘\b’ matches a word boundary
  6. ‘\B’ matches characters which are not a word boundary
  7. ‘\`’ matches the beginning of the whole input
  8. ‘\'’ matches the end of the whole input

Grouping is performed with parentheses ‘()’. An unmatched ‘)’ matches just itself. A backslash followed by a digit acts as a back-reference and matches the same thing as the previous grouped expression indicated by that number. For example ‘\2’ matches the second group expression. The order of group expressions is determined by the position of their opening parenthesis ‘(’.

The alternation operator is ‘|’.

The characters ‘^’ and ‘$’ always represent the beginning and end of a string respectively, except within square brackets. Within brackets, ‘^’ can be used to invert the membership of the character class being specified.

‘*’, ‘+’ and ‘?’ are special at any point in a regular expression except:

  1. At the beginning of a regular expression
  2. After an open-group, signified by ‘(’
  3. After the alternation operator ‘|’

Intervals are specified by ‘{’ and ‘}’. Invalid intervals are treated as literals, for example ‘a{1’ is treated as ‘a\{1’

The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups.

Next: , Previous: , Up: Regular expression syntaxes   [Contents][Index]

19.7.6 ‘grep’ regular expression syntax

The character ‘.’ matches any single character.

‘\+’

indicates that the regular expression should match one or more occurrences of the previous atom or regexp.

‘\?’

indicates that the regular expression should match zero or one occurrence of the previous atom or regexp.

‘+ and ?’

match themselves.

Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example ‘[z-a]’, are invalid. Within square brackets, ‘\’ is taken literally. Character classes are supported; for example ‘[[:digit:]]’ will match a single decimal digit.

GNU extensions are supported:

  1. ‘\w’ matches a character within a word
  2. ‘\W’ matches a character which is not within a word
  3. ‘\<’ matches the beginning of a word
  4. ‘\>’ matches the end of a word
  5. ‘\b’ matches a word boundary
  6. ‘\B’ matches characters which are not a word boundary
  7. ‘\`’ matches the beginning of the whole input
  8. ‘\'’ matches the end of the whole input

Grouping is performed with backslashes followed by parentheses ‘\(’, ‘\)’. A backslash followed by a digit acts as a back-reference and matches the same thing as the previous grouped expression indicated by that number. For example ‘\2’ matches the second group expression. The order of group expressions is determined by the position of their opening parenthesis ‘\(’.

The alternation operator is ‘\|’.

The character ‘^’ only represents the beginning of a string when it appears:

  1. At the beginning of a regular expression
  2. After an open-group, signified by ‘\(’
  3. After a newline
  4. After the alternation operator ‘\|’

The character ‘$’ only represents the end of a string when it appears:

  1. At the end of a regular expression
  2. Before a close-group, signified by ‘\)’
  3. Before a newline
  4. Before the alternation operator ‘\|’

‘\*’, ‘\+’ and ‘\?’ are special at any point in a regular expression except:

  1. At the beginning of a regular expression
  2. After an open-group, signified by ‘\(’
  3. After a newline
  4. After the alternation operator ‘\|’

Intervals are specified by ‘\{’ and ‘\}’. Invalid intervals such as ‘a\{1z’ are not accepted.

The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups.

Next: , Previous: , Up: Regular expression syntaxes   [Contents][Index]

19.7.7 ‘posix-awk’ regular expression syntax

The character ‘.’ matches any single character except the null character.

‘+’

indicates that the regular expression should match one or more occurrences of the previous atom or regexp.

‘?’

indicates that the regular expression should match zero or one occurrence of the previous atom or regexp.

‘\+’

matches a ‘+’

‘\?’

matches a ‘?’.

Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example ‘[z-a]’, are invalid. Within square brackets, ‘\’ can be used to quote the following character. Character classes are supported; for example ‘[[:digit:]]’ will match a single decimal digit.

GNU extensions are not supported and so ‘\w’, ‘\W’, ‘\<’, ‘\>’, ‘\b’, ‘\B’, ‘\`’, and ‘\'’ match ‘w’, ‘W’, ‘<’, ‘>’, ‘b’, ‘B’, ‘`’, and ‘'’ respectively.

Grouping is performed with parentheses ‘()’. An unmatched ‘)’ matches just itself. A backslash followed by a digit acts as a back-reference and matches the same thing as the previous grouped expression indicated by that number. For example ‘\2’ matches the second group expression. The order of group expressions is determined by the position of their opening parenthesis ‘(’.

The alternation operator is ‘|’.

The characters ‘^’ and ‘$’ always represent the beginning and end of a string respectively, except within square brackets. Within brackets, ‘^’ can be used to invert the membership of the character class being specified.

‘*’, ‘+’ and ‘?’ are special at any point in a regular expression except the following places, where they are not allowed:

  1. At the beginning of a regular expression
  2. After an open-group, signified by ‘(’
  3. After the alternation operator ‘|’

Intervals are specified by ‘{’ and ‘}’. Invalid intervals are treated as literals, for example ‘a{1’ is treated as ‘a\{1’

The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups.

Next: , Previous: , Up: Regular expression syntaxes   [Contents][Index]

19.7.8 ‘posix-basic’ regular expression syntax

This is a synonym for ed.

Next: , Previous: , Up: Regular expression syntaxes   [Contents][Index]

19.7.9 ‘posix-egrep’ regular expression syntax

This is a synonym for egrep.

Next: , Previous: , Up: Regular expression syntaxes   [Contents][Index]

19.7.10 ‘posix-extended’ regular expression syntax

The character ‘.’ matches any single character except the null character.

‘+’

indicates that the regular expression should match one or more occurrences of the previous atom or regexp.

‘?’

indicates that the regular expression should match zero or one occurrence of the previous atom or regexp.

‘\+’

matches a ‘+’

‘\?’

matches a ‘?’.

Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example ‘[z-a]’, are invalid. Within square brackets, ‘\’ is taken literally. Character classes are supported; for example ‘[[:digit:]]’ will match a single decimal digit.

GNU extensions are supported:

  1. ‘\w’ matches a character within a word
  2. ‘\W’ matches a character which is not within a word
  3. ‘\<’ matches the beginning of a word
  4. ‘\>’ matches the end of a word
  5. ‘\b’ matches a word boundary
  6. ‘\B’ matches characters which are not a word boundary
  7. ‘\`’ matches the beginning of the whole input
  8. ‘\'’ matches the end of the whole input

Grouping is performed with parentheses ‘()’. An unmatched ‘)’ matches just itself. A backslash followed by a digit acts as a back-reference and matches the same thing as the previous grouped expression indicated by that number. For example ‘\2’ matches the second group expression. The order of group expressions is determined by the position of their opening parenthesis ‘(’.

The alternation operator is ‘|’.

The characters ‘^’ and ‘$’ always represent the beginning and end of a string respectively, except within square brackets. Within brackets, ‘^’ can be used to invert the membership of the character class being specified.

‘*’, ‘+’ and ‘?’ are special at any point in a regular expression except the following places, where they are not allowed:

  1. At the beginning of a regular expression
  2. After an open-group, signified by ‘(’
  3. After the alternation operator ‘|’

Intervals are specified by ‘{’ and ‘}’. Invalid intervals such as ‘a{1z’ are not accepted.

The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups.

Next: , Previous: , Up: Regular expression syntaxes   [Contents][Index]

19.7.11 ‘posix-minimal-basic’ regular expression syntax

The character ‘.’ matches any single character except the null character.

Bracket expressions are used to match ranges of characters. Bracket expressions where the range is backward, for example ‘[z-a]’, are invalid. Within square brackets, ‘\’ is taken literally. Character classes are supported; for example ‘[[:digit:]]’ will match a single decimal digit.

GNU extensions are supported:

  1. ‘\w’ matches a character within a word
  2. ‘\W’ matches a character which is not within a word
  3. ‘\<’ matches the beginning of a word
  4. ‘\>’ matches the end of a word
  5. ‘\b’ matches a word boundary
  6. ‘\B’ matches characters which are not a word boundary
  7. ‘\`’ matches the beginning of the whole input
  8. ‘\'’ matches the end of the whole input

Grouping is performed with backslashes followed by parentheses ‘\(’, ‘\)’. A backslash followed by a digit acts as a back-reference and matches the same thing as the previous grouped expression indicated by that number. For example ‘\2’ matches the second group expression. The order of group expressions is determined by the position of their opening parenthesis ‘\(’.

The character ‘^’ only represents the beginning of a string when it appears:

  1. At the beginning of a regular expression
  2. After an open-group, signified by ‘\(’

The character ‘$’ only represents the end of a string when it appears:

  1. At the end of a regular expression
  2. Before a close-group, signified by ‘\)’

Intervals are specified by ‘\{’ and ‘\}’. Invalid intervals such as ‘a\{1z’ are not accepted.

The longest possible match is returned; this applies to the regular expression as a whole and (subject to this constraint) to subexpressions within groups.

Previous: , Up: Regular expression syntaxes   [Contents][Index]

19.7.12 ‘sed’ regular expression syntax

This is a synonym for ed.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

20 Build Infrastructure Modules

Gnulib has a couple of modules that don’t provide code, but rather extend the GNU Build System. That is, they are convenience facilities for use with GNU Automake (in particular).

Next: , Up: Build Infrastructure Modules   [Contents][Index]

20.1 Searching for Libraries

The following macros check for the presence or location of certain C, C++, or Fortran library archive files.

Simple Library Tests

The macros AC_CHECK_LIB, AC_SEARCH_LIBS from GNU Autoconf check for the presence of certain C, C++, or Fortran library archive files. The libraries are looked up in the default linker path—a system dependent list of directories, that usually contains the /usr/lib directory—and those directories given by -L options in the LDFLAGS variable.

Locating Libraries

The following macros, defined in the Gnulib module havelib, search for the location of certain C, C++, or Fortran library archive files and make the found location available to the compilation process and to further Autoconf tests.

Macro: AC_LIB_LINKFLAGS(name, [dependencies])

Searches for lib<name> and the libraries corresponding to explicit and implicit dependencies. Sets and AC_SUBSTs the LIB<NAME> and LTLIB<NAME> variables (with <NAME> in upper case) and augments the CPPFLAGS variable by -I options.

This macro should be used when lib<name> is expected to be found.

Macro: AC_LIB_HAVE_LINKFLAGS(name, [dependencies], [includes], [testcode], [missing-message])

Searches for lib<name> and the libraries corresponding to explicit and implicit dependencies, together with the specified include files and the ability to compile and link the specified testcode. The missing-message defaults to no and may contain additional hints for the user. If found, it sets and AC_SUBSTs HAVE_LIB<NAME>=yes and the LIB<NAME> and LTLIB<NAME> variables (with <NAME> in upper case) and augments the CPPFLAGS variable by -I options, and #defines HAVE_LIB<NAME> to 1. Otherwise, it sets and AC_SUBSTs HAVE_LIB<NAME>=no and LIB<NAME> and LTLIB<NAME> to empty.

These macros assume that when a library is installed in some_directory/lib, its include files are installed in some_directory/include.

The complexities that AC_LIB_LINKFLAGS and AC_LIB_HAVE_LINKFLAGS deal with are the following:

  • The library is not necessarily already in the search path (CPPFLAGS for the include file search path, LDFLAGS for the library search path). The macro provides a ‘--with-lib<name>’ option. The user of the ‘configure’ script can use this option to indicate the location of the library and its include files. If not provided, the --prefix directory is searched as well.
  • The library is not necessarily already in the run time library search path. To avoid the need for setting an environment variable like LD_LIBRARY_PATH, the macro adds the appropriate run time search path options to the LIB<NAME> variable. This works on most systems. It can also be inhibited: The user of ‘configure’ can use the --disable-rpath option to force an installation that doesn’t contain hardcoded library search paths but instead may require the use of an environment variable like LD_LIBRARY_PATH.

The macros also set a variable LTLIB<NAME>, that should be used when linking with libtool. Both LTLIB<NAME> and LIB<NAME> contain essentially the same option, but where LIB<NAME> contains platform dependent flags like ‘-Wl,-rpath’, LTLIB<NAME> contains platform independent flags like ‘-R’.

If you, by mistake, use LIB<NAME> instead of LTLIB<NAME> when linking with libtool, you will observe that the binaries created in the build dir will prefer the shared libraries in the installation directories over the shared libraries in the build dir; this can lead to all sorts of build failures, test failures, or crashes!

If you, on the other hand, by mistake, use LTLIB<NAME> instead of LIB<NAME> when linking without libtool, you will observe build failures, because the ‘-R’ options contained in LTLIB<NAME> are not valid options to compilers such as GCC.

Example of using AC_LIB_LINKFLAGS

Suppose you want to use libz, the compression library.

  1. In configure.ac you add the line 
      AC_CONFIG_AUX_DIR([build-aux])
  AC_LIB_LINKFLAGS([z])

    Note that since the AC_LIB_LINKFLAGS invocation modifies the CPPFLAGS, it should precede all tests that check for header files, declarations, structures or types.

  2. To the package’s build-aux directory you add the file config.rpath, also part of the Gnulib havelib module. (gnulib-tool will usually do this for you automatically.)
  3. In Makefile.in you add @LIBZ@ to the link command line of your program. Or, if you are using Automake, you add $(LIBZ) to the LDADD variable that corresponds to your program.

Dependencies

The dependencies list is a space separated list of library names that libname is known to depend upon. Example: If libfooy depends on libfoox, and libfooz depends on libfoox and libfooy, you can write: 

AC_LIB_LINKFLAGS([foox])
AC_LIB_LINKFLAGS([fooy], [foox])
AC_LIB_LINKFLAGS([fooz], [foox fooy])

Explicit dependencies are necessary if you cannot assume that a .la file, created by libtool, is installed. If you can assume that libfooy.la is installed by libtool (and has not been omitted by the package distributor!), you can omit the explicit dependency and just write 

AC_LIB_LINKFLAGS([fooy])

This way, you don’t need to know in advance which libraries the needed library depends upon.

Static vs. shared

The macros find the libraries regardless whether they are installed as shared or static libraries.

CPPFLAGS vs. LDFLAGS

The macros determine the directories that should be added to the compiler preprocessor’s search path and to the linker’s search path. For the compiler preprocessor, -I options with the necessary directories are added to the CPPFLAGS variable, for use by the whole package. For the linker, appropriate options are added to the LIB<NAME> and LTLIB<NAME> variables, for use during linking by those programs and libraries that need the dependency on lib<name>. You need to use the value of LIB<NAME> or LTLIB<NAME> in the Makefiles. LTLIB<NAME> is for use with libtool, whereas LIB<NAME> is for when libtool is not involved in linking.

The macros do not check whether the include files and the library found match. If you want to verify this at configure time, one technique is to have a version number in the include files and a version number in the library, like this: 

  #define LIBNAME_VERSION 10203
  extern int libname_version; /* initialized to LIBNAME_VERSION */

and use a test like 

  AC_TRY_RUN([int main () { return libname_version != LIBNAME_VERSION; }])

Bi-arch systems

A bi-arch system is one where

  • the processor has a 32-bit execution mode and a 64-bit execution mode (for example, x86_64, ia64, sparc64, powerpc64), and
  • 32-bit mode libraries and executables and 64-bit mode libraries are both installed, and
  • 32-bit mode libraries and object files cannot be mixed with 64-bit mode ones.

On several types of such systems, for historical reasons, the 32-bit libraries are installed in prefix/lib, whereas the 64-bit libraries are installed in

  • prefix/lib64 on many glibc systems,
  • prefix/lib/64 on Solaris systems.

On such systems, in 64-bit mode, configure will search for the libraries in prefix/lib64 or prefix/lib/64, respectively, not in prefix/lib. A user can adhere to these system-wide conventions by using the ‘--libdir’ option when installing packages. When a user has already installed packages in 64-bit mode using the GNU default ‘--libdir=prefix/lib’, he can make this directory adhere to the system-wide convention by placing a symbolic link:

On glibc systems:

ln -s lib prefix/lib64

On Solaris systems:

ln -s . prefix/lib/64

Next: , Previous: , Up: Build Infrastructure Modules   [Contents][Index]

20.2 Controlling the Exported Symbols of Shared Libraries

The lib-symbol-visibility module allows precise control of the symbols exported by a shared library. This is useful because

  • It prevents abuse of undocumented APIs of your library. Symbols that are not exported from the library cannot be used. This eliminates the problem that when the maintainer of the library changes internals of the library, maintainers of other projects cry “breakage”. Instead, these maintainers are forced to negotiate the desired API from the maintainer of the library.
  • It reduces the risk of symbol collision between your library and other libraries. For example, the symbol ‘readline’ is defined in several libraries, most of which don’t have the same semantics and the same calling convention as the GNU readline library.
  • It reduces the startup time of programs linked to the library. This is because the dynamic loader has less symbols to process.
  • It allows the compiler to generate better code. Within a shared library, a call to a function that is a global symbol costs a “call” instruction to a code location in the so-called PLT (procedure linkage table) which contains a “jump” instruction to the actual function’s code. (This is needed so that the function can be overridden, for example by a function with the same name in the executable or in a shared library interposed with LD_PRELOAD.) Whereas a call to a function for which the compiler can assume that it is in the same shared library is just a direct “call” instructions. Similarly for variables: A reference to a global variable fetches a pointer in the so-called GOT (global offset table); this is a pointer to the variable’s memory. So the code to access it is two memory load instructions. Whereas for a variable which is known to reside in the same shared library, it is just a direct memory access: one memory load instruction.

There are traditionally three ways to specify the exported symbols of a shared library.

  • The programmer specifies the list of symbols to be exported when the shared library is created. Usually a command-line option is passed to the linker, with the name of a file containing the symbols.

    The upside of this approach is flexibility: it allows the same code to be used in different libraries with different export lists. The downsides are: 1. it’s a lot of maintenance overhead when the symbol list is platform dependent, 2. it doesn’t work well with C++, due to name mangling.

  • The programmer specifies a “hidden” attribute for every variable and function that shall not be exported.

    The drawbacks of this approach are: Symbols are still exported from the library by default. It’s a lot of maintenance work to mark every non- exported variable and function. But usually the exported API is quite small, compared to the internal API of the library. And it’s the wrong paradigm: It doesn’t force thinking when introducing new exported API.

  • The programmer specifies a “hidden” attribute for all files that make up the shared library, and an “exported” attribute for those symbols in these files that shall be exported.

    This is perfect: It burdens the maintainer only for exported API, not for library-internal API. And it keeps the annotations in the source code.

GNU libtool’s -export-symbols option implements the first approach. The script declared.sh from Gnulib can help to produce the list of symbols.

This gnulib module implements the third approach. For this it relies on GNU GCC 4.0 or newer, namely on its ‘-fvisibility=hidden’ command-line option and the “visibility” attribute. (The “visibility” attribute was already supported in GCC 3.4, but without the command line option, introduced in GCC 4.0, the third approach could not be used.)

More explanations on this subject can be found in https://gcc.gnu.org/wiki/Visibility, which contains more details on the GCC features and additional advice for C++ libraries, and in Ulrich Drepper’s paper https://www.akkadia.org/drepper/dsohowto.pdf, which also explains other tricks for reducing the startup time impact of shared libraries.

The gnulib autoconf macro gl_VISIBILITY tests for GCC 4.0 or newer. It defines a Makefile variable @CFLAG_VISIBILITY@ containing ‘-fvisibility=hidden’ or nothing. It also defines as a C macro and as a substituted variable: @HAVE_VISIBILITY@. Its value is 1 when symbol visibility control is supported, and 0 otherwise.

As of 2022, symbol visibility control is supported on

  • ELF platforms (glibc, Linux, *BSD, Solaris) with GCC or clang,
  • macOS,
  • AIX with gcc or xlclang.

It is not supported on

  • Other compilers on ELF platforms or AIX,
  • Windows.

To use this module in a library, say libfoo, you will do these steps:

  1. Add @CFLAG_VISIBILITY@ or (in a Makefile.am) $(CFLAG_VISIBILITY) to the CFLAGS for the compilation of the sources that make up the library.
  2. Add a C macro definition, say ‘-DBUILDING_LIBFOO’, to the CPPFLAGS for the compilation of the sources that make up the library.
  3. Define a macro specific to your library like this. 
    #if HAVE_VISIBILITY && BUILDING_LIBFOO
# define LIBFOO_SHLIB_EXPORTED __attribute__((__visibility__("default")))
#else
# define LIBFOO_SHLIB_EXPORTED
#endif

    This macro should be enabled in all public header files of your library.

  4. Annotate all variable, function and class declarations in all public header files of your library with ‘LIBFOO_SHLIB_EXPORTED’. This annotation can occur at different locations: between the ‘extern’ and the type or return type, or just before the entity being declared, or after the entire declarator. My preference is to put it right after ‘extern’, so that the declarations in the header files remain halfway readable.

Note that the precise control of the exported symbols will not work with other compilers than GCC >= 4.0, and will not work on systems where the assembler or linker lack the support of “hidden” visibility. Therefore, it’s good if, in order to reduce the risk of collisions with symbols in other libraries, you continue to use a prefix specific to your library for all non-static variables and functions and for all C++ classes in your library.

Note about other compilers: MSVC support can be added easily, by extending the definition of the macro mentioned above, to something like this: 

#if HAVE_VISIBILITY && BUILDING_LIBFOO
# define LIBFOO_SHLIB_EXPORTED __attribute__((__visibility__("default")))
#elif (defined _WIN32 && !defined __CYGWIN__) && @BUILDING_SHARED@ && BUILDING_LIBFOO
# if defined DLL_EXPORT
#  define LIBFOO_SHLIB_EXPORTED __declspec(dllexport)
# else
#  define LIBFOO_SHLIB_EXPORTED
# endif
#elif (defined _WIN32 && !defined __CYGWIN__) && @BUILDING_SHARED@
# define LIBFOO_SHLIB_EXPORTED __declspec(dllimport)
#else
# define LIBFOO_SHLIB_EXPORTED
#endif

Here BUILDING_SHARED is an Autoconf variable that you have to define. It ought to evaluate to 1 in a build configured with ‘--enable-shared’, or to 0 in a build configured with ‘--disable-shared’. You may use the following ‘configure.ac’ snippet: 

  if test "$enable_shared" = yes; then
    BUILDING_SHARED=1
  else
    BUILDING_SHARED=0
  fi
  AC_SUBST([BUILDING_SHARED])

And DLL_EXPORT is defined by Libtool, on Windows platforms, when compiling for a shared library (called DLL under Windows). It is not defined when Libtool compiles an object file meant to be linked statically into some executable.

Next: , Previous: , Up: Build Infrastructure Modules   [Contents][Index]

20.3 LD Version Scripts

The lib-symbol-versions module can be used to add shared library versioning support. Currently, only GNU LD and the Solaris linker supports this.

Version scripts provides information that can be used by GNU/Linux distribution packaging tools. For example, Debian has a tool dpkg-shlibdeps that can determine the minimal required version of each dependency (by looking at the symbol list) and stuff the information into the Debian specific packaging files.

For more information and other uses of version scripts, see Ulrich Drepper’s paper https://www.akkadia.org/drepper/dsohowto.pdf

You use the module by importing it to your library, and then add the following lines to the Makefile.am that builds the library: 

if HAVE_LD_VERSION_SCRIPT
libfoo_la_LDFLAGS += -Wl,--version-script=$(srcdir)/libfoo.map
endif

The version script file format is documented in the GNU LD manual, but a small example would be: 

LIBFOO_1.0 {
  global:
    libfoo_init; libfoo_doit; libfoo_done;

  local:
    *;
};

If you target platforms that do not support linker scripts (i.e., all platforms that doesn’t use GNU LD) you may want to consider a more portable but less powerful alternative: libtool -export-symbols. It will hide internal symbols from your library, but will not add ELF versioning symbols. Your usage would then be something like: 

if HAVE_LD_VERSION_SCRIPT
libfoo_la_LDFLAGS += -Wl,--version-script=$(srcdir)/libfoo.map
else
libfoo_la_LDFLAGS += -export-symbols $(srcdir)/libfoo.sym
endif

See the Libtool manual for the file syntax, but a small example would be: 

libfoo_init
libfoo_doit
libfoo_done

To avoid the need for a *.sym file if your symbols are easily expressed using a regular expression, you may use -export-symbols-regex: 

if HAVE_LD_VERSION_SCRIPT
libfoo_la_LDFLAGS += -Wl,--version-script=$(srcdir)/libfoo.map
else
libfoo_la_LDFLAGS += -export-symbols-regex '^libfoo_.*'
endif

For more discussions about symbol visibility, rather than shared library versioning, see the lib-symbol-visibility module (see Controlling the Exported Symbols of Shared Libraries).

Next: , Previous: , Up: Build Infrastructure Modules   [Contents][Index]

20.4 configmake

The configmake module builds a C include file named configmake.h containing the usual installation directory values; for example, those specified by --prefix or --libdir to configure. Each variable is given a #define with an all-uppercase macro name, such as PREFIX and LIBDIR. (Automake cannot create this file directly because the user might override directory values at make time.)

Specifically, the module retrieves values of the variables through configure followed by make, not directly through configure, so that a user who sets some of these variables consistently on the make command line gets correct results.

One advantage of this approach, compared to the classical approach of adding -DLIBDIR=\"$(libdir)\" etc. to AM_CPPFLAGS, is that it protects against the use of undefined variables. That is, if, say, $(libdir) is not set in the Makefile, LIBDIR is not defined by this module, and code using LIBDIR gives a compilation error.

Another advantage is that make output is shorter.

For the complete list of variables which are #defined this way, see the file gnulib/modules/configmake, or inspect your resulting gnulib Makefile.

Next: , Previous: , Up: Build Infrastructure Modules   [Contents][Index]

20.5 warnings

The warnings module allows regularly building a package with more GCC warnings than the default warnings emitted by GCC. It is often used indirectly through the manywarnings module (see manywarnings).

It provides the following functionality:

  • You can select some warning options, such as ‘-Wall’, to be enabled whenever building with a GCC version that supports these options. The user can choose to override these warning options by providing the opposite options in the CFLAGS variable at configuration time.
  • You can make these warnings apply to selected directories only. In projects where subprojects are maintained by different people, or where parts of the source code are imported from external sources (for example from gnulib), it is useful to apply different warning options to different directories.
  • It lets you use ‘-Werror’ at ‘make distcheck’ time, to verify that on the maintainer’s system, no warnings remain. (Note that use of ‘-Werror’ in CFLAGS does not work in general, because it may break autoconfiguration.)
  • Similarly, it lets you use ‘-Werror’ when the builder runs configure with an option such as --enable-gcc-warnings.

To use this module, you need the following:

  1. In configure.ac, use for example 
    gl_WARN_ADD([-Wall], [WARN_CFLAGS])
gl_WARN_ADD([-Wpointer-arith], [WARN_CFLAGS])
  2. In the directories which shall use WARN_CFLAGS, use it in the definition of AM_CFLAGS, like this: 
    AM_CFLAGS = $(WARN_CFLAGS)

    Note that the AM_CFLAGS is used in combination with CFLAGS and before CFLAGS in build rules emitted by Automake. This allows the user to provide CFLAGS that override the WARN_CFLAGS.

‘gl_WARN_ADD([-Werror])’ is intended for developers, and should be avoided in contexts where it would affect ordinary installation builds. The warnings emitted by GCC depend, to some extent, on the contents of the system header files, on the size and signedness of built-in types, etc. Use of ‘-Werror’ would cause frustration to all users on platforms that the maintainer has not tested before the release. It is better if ‘-Werror’ is off by default, and is enabled only by developers. For example, ‘-Werror’ could affect ‘make distcheck’ or ‘configure --enable-gcc-warnings’ as mentioned above.

Next: , Previous: , Up: Build Infrastructure Modules   [Contents][Index]

20.6 manywarnings

The manywarnings module enables many GCC warnings for your package. Here is an example use: 

AC_ARG_ENABLE([gcc-warnings],
  [AS_HELP_STRING([[--enable-gcc-warnings[=TYPE]]],
    [control generation of GCC warnings.  The TYPE 'no' disables
     warnings; 'yes' (default) generates cheap warnings;
     'expensive' in addition generates expensive warnings.])])

AS_IF([test "$enable_gcc_warnings" != no],
  [
   # Set up the list of unwanted warning options.
   nw=
   if test "$enable_gcc_warnings" != expensive; then
     nw="$nw -fanalyzer"
   fi
   nw="$nw -Wbad-function-cast" # Casting a function's result is not more
                                # dangerous than casting any other value.
   nw="$nw -Winline"            # It's OK to not inline.
   nw="$nw -Wsign-compare"      # Too many false alarms.
   nw="$nw -Wsystem-headers"    # Don't warn in system headers.

   # Setup the list of meaningful warning options for the C compiler.
   # The list comes from manywarnings.m4. Warning options that are not
   # generally meaningful have already been filtered out (cf.
   # build-aux/gcc-warning.spec).
   gl_MANYWARN_ALL_GCC([possible_warning_options])

   # Compute the list of warning options that are desired.
   gl_MANYWARN_COMPLEMENT([desired_warning_options],
                          [$possible_warning_options], [$nw])
   # Compute the list of remaining undesired warning options.
   # Namely those, that were not in manywarnings.m4 because they were
   # already listed in build-aux/gcc-warning.spec; this includes those
   # that are implied by -Wall.
   gl_MANYWARN_COMPLEMENT([remaining_undesired_warning_options],
                          [$nw], [$possible_warning_options])

   # Add the desired warning options to WARN_CFLAGS.
   for w in $desired_warning_options; do
     gl_WARN_ADD([$w])
   done

   # Add the opposites of the remaining undesired warning options to
   # WARN_CFLAGS.
   for w in `echo "$remaining_undesired_warning_options" | sed -e 's/-W/-Wno-/g'`; do
     gl_WARN_ADD([$w])
   done
])

This module sets up many GCC warning options.

When you use it for the first time, it is common practice to do it as follows:

  • Start with the newest major release of GCC. This will save you time, because some warning options produce many false alarms with older versions of GCC.
  • Consider the platforms commonly used when enabling GCC warnings. This includes not only target architectures and operating systems, but also optimization options, which can greatly affect the warnings generated. Makefiles generated by configure default to -O2 optimization. If you also commonly build with -O0 or other optimization options, you can compile again with those options. Using more optimizations catches more bugs, because the compiler does a better static analysis of the program when optimizing more. Also, some warning options that diagnose suboptimal code generation, such as -Winline, are not effective when not optimizing. On the other hand, if it’s frequent to build the package with warnings but without optimizations, for debugging purposes, then you don’t want to see undesired warnings in these phases of development either.
  • Compile the package with an empty nw value, that is, with all possible warnings enabled.
  • Then you will go through the list of warnings. Since there are likely many warnings, the first time, it’s a good idea to sort them by warning option first: 
    $ grep warning: make-output.log \
  | sed -e 's/^\(.*\) \[\(-W.*\)\]$/\2  \1/' | sort -k1
  • You will likely deactivate warnings that occur often and don’t point to mistakes in the code, by adding them to the ‘nw’ variable, then reconfiguring and recompiling. When warnings point to real mistakes and bugs in the code, you will of course not disable them but fix your code to silence the warning instead.

    Many GCC warning options usually don’t point to mistakes in the code; these warnings enforce a certain programming style. It is a project management decision whether you want your code to follow any of these styles. Note that some of these programming styles are conflicting. You cannot have them all; you have to choose among them.

    When a warning option pinpoints real bugs occasionally, but it also whines about a few code locations which are fine, we recommend to leave the warning option enabled. Whether you then live with the remaining few warnings, or choose to disable them one-by-one through #pragma GCC diagnostic ignored "option" (see Diagnostic Pragmas in Using the GNU Compiler Collection, https://gcc.gnu.org/onlinedocs/gcc/Diagnostic-Pragmas.html), is again a project management decision.

When a new major version of GCC is released, the Gnulib maintainers add the newly available warning options into the gl_MANYWARN_ALL_GCC macro. You will then enjoy the benefits of the new warnings, simply by updating to the newest Gnulib. If some of the new warnings are undesired, you can add them to the ‘nw’ variable, as described above.

Comments on particular warning flags:

‘-fanalyzer’

The manywarnings module by default uses GCC’s -fanalyzer option, as this issues some useful warnings. (It can also help GCC generate better code.) However, -fanalyzer can greatly slow down compilation, and in programs with large modules it can be so slow as to be unusable, so it is common for configure to disable it unless configure is given an option like --enable-gcc-warnings=expensive.

‘-fstrict-aliasing’

Although the manywarnings module does not enable GCC’s -fstrict-aliasing option, it is enabled by default if you compile with -O2 or higher optimization, and can help GCC generate better warnings.

‘-Wanalyzer-malloc-leak’

The -fanalyzer option generates many false alarms about malloc leaks, which manywarnings suppresses by also using -Wno-analyzer-malloc-leak.

‘-fstrict-flex-arrays’

The manywarnings module by default uses GCC’s -fstrict-flex-arrays option if available, so that GCC can warn about nonportable usage of flexible array members. In a few cases this can help GCC generate better code, so it is not strictly a warning option.

‘-Wsign-compare’

GCC and Clang generate too many false alarms with -Wsign-compare, and we don’t recommend that warning. You can disable it by using gl_WARN_ADD([-Wno-sign-compare]) as illustrated above. Programs using Gnulib generally don’t enable that warning when compiling Gnulib code. If you happen to find a real bug with that warning we’d like to know it.

Next: , Previous: , Up: Build Infrastructure Modules   [Contents][Index]

20.7 Running self-tests under valgrind

For projects written in C or similar languages, running the self-tests under Valgrind can reveal hard to find memory issues. Gnulib supports two ways to make use of Valgrind: one that enables use of Valgrind at configure time, when configure found it to be present; and one at the discretion of the developer.

Next: , Up: Running self-tests under valgrind   [Contents][Index]

20.7.1 Using valgrind without developer intervention

The valgrind-tests module searches for Valgrind at configure time and declares the LOG_VALGRIND automake variable for use with automake’s LOG_COMPILER.

After importing the valgrind-tests module to your project, you use it by adding the following to the Makefile.am that runs the self-tests: 

LOG_COMPILER = $(LOG_VALGRIND)

This will run all self-checks under valgrind.

Replace LOG_COMPILER with TESTS_ENVIRONMENT if you are using the old serial test harness. The parallel test harness has been the default in automake since version 1.11.3, but if you are using an older automake, or put ‘serial-tests’ in ‘AM_INIT_AUTOMAKE’/‘AUTOMAKE_OPTIONS’ you would still be using the serial test harness.

If you desire a project-wide decision that valgrind is not enabled by default, but still allow users to enable it with --enable-valgrind-tests you may put the following in configure.ac before gl_INIT. 

gl_VALGRIND_TESTS_DEFAULT_NO

Next: , Previous: , Up: Running self-tests under valgrind   [Contents][Index]

20.7.2 Valgrind options

The VALGRIND variable holds the name of the valgrind binary and some options passed to valgrind. You may provide additional options that are passed to valgrind using the ‘VALGRINDFLAGS’ variable, for example: 

./configure VALGRINDFLAGS="--suppressions=~/local.supp"

Alternatively during build phase: 

make check VALGRINDFLAGS="--suppressions=~/local.supp"

This is useful if you have a valgrind suppression files that are needed to avoid triggering errors for known errors, typically in system libraries.

The VALGRIND variable include options that are useful when valgrind is run non-interactively through the test harness. The default parameters are -q to silence the output, --error-exitcode=1 to cause valgrind errors to be treated as fatal errors, and --leak-check=full to check for memory leaks.

These options can be controlled through the DEFAULT_VALGRINDFLAGS variable. For example, when configuring the package: 

./configure DEFAULT_VALGRINDFLAGS="--quiet"

Alternatively, during the build phase: 

make check DEFAULT_VALGRINDFLAGS="--quiet"

That would have the effect of removing --error-exitcode=1 and --leak-check=full from the default options, thus causing any valgrind errors to be silently ignored, instead of causing fatal test failures.

As a developer you may use the variables in configure.ac before calling gl_INIT, like this if your program has deeply-nested call chains: 

gl_EARLY
...
VALGRINDFLAGS="$VALGRINDFLAGS --num-callers=42"
...
gl_INIT

Note that any user-supplied VALGRINDFLAGS value is preserved, which is usually what you want.

Finally, as a developer you may want to provide additional per-directory options to valgrind and the AM_VALGRINDFLAGS variable can be used for this. For example: 

AM_VALGRINDFLAGS = --suppressions=$(srcdir)/local-valgrind.supp
LOG_COMPILER = $(LOG_VALGRIND)

Next: , Previous: , Up: Running self-tests under valgrind   [Contents][Index]

20.7.3 Using valgrind at the developer’s discretion

In this approach, you define a Makefile.am variable ‘VALGRIND’ (or, more abstractly, ‘CHECKER’), that is usually set to empty. When you have configured and built the package and you decide that you want to run the tests with valgrind, you do so by modifying the definition of ‘VALGRIND’ in the Makefile.

Previous: , Up: Running self-tests under valgrind   [Contents][Index]

20.7.4 How to use Valgrind with shell scripts

It is not desirable to apply valgrind to shell scripts or other non-binaries, because

  • It is wasteful, and you usually don’t want to look for memory leaks in bash.
  • On a bi-arch system, you may get an error message such as "valgrind: wrong executable class (eg. 32-bit instead of 64-bit)".

There are two ways to avoid this:

  • Using the Automake parallel-tests feature, you can use the following instead: 
    TEST_EXTENSIONS = .pl .sh
LOG_COMPILER = $(LOG_VALGRIND)

    Then valgrind will only be used for the non-.sh and non-.pl tests.

    For old automake (before 1.11.3), you will need AUTOMAKE_OPTIONS = parallel-tests to enable the parallel test harness.

  • You can make use of the build-aux/run-test script from Gnulib. Add these lines to your Makefile.am: 
    LOG_COMPILER += $(SHELL) $(top_srcdir)/build-aux/run-test '$(LOG_VALGRIND)'

    Replace LOG_COMPILER with TESTS_ENVIRONMENT if you use the old serial test harness.

However, with this measure in place, binaries invoked through scripts will not be invoked under valgrind. This can be solved by defining environment variables in the TESTS_ENVIRONMENT variable that are then used by the shell scripts. For example, add the following: 

TESTS_ENVIRONMENT = VALGRIND='$(LOG_VALGRIND)'

And then modify the shell scripts to invoke the binary prefixed with $VALGRIND.

Next: , Previous: , Up: Build Infrastructure Modules   [Contents][Index]

20.8 Package version management

The goals of a package maintainer, when dealing with the version number of a package, are:

  • Programs should identify themselves with that version number when invoked as program --version.
  • Every package tarball should contain the version number, in up to four ways:
    • The tarball name should be package-version.tar.gz.
    • The tarball should unpack into a directory named package-version.
    • Programs built from that tarball should identify themselves when invoked as program --version.
    • Documentation (especially in PDF format) and man pages may contain the version number, as an important bit of meta information.
  • The package maintainer should be able to easily set the version number before making a release, and doing so should be quick.
  • When a contributor is building from the git repository (as opposed to a tarball), the version number should, by default, reflect the git commit, in order to avoid confusion w.r.t. official releases.

Here’s how the GNU Build System and Gnulib achieve these goals.

Next: , Up: Package version management   [Contents][Index]

20.8.1 Setting the package version

When the maintainer has decided about the version number for the next build (and likely also the next tarball), they implement that decision by storing this version number in a file named .tarball-version at the top level of the package. This is a simple one-line text file.

The maintainer can, alternatively, decide to let the git version be the version number. To implement this choice, they remove the file .tarball-version at the top level of the package.

The actual version number comes from an invocation of the program git-version-gen, part of the Gnulib module git-version-gen. It looks at the file .tarball-version, if that exists, and at the current checkout, otherwise.

The file .tarball-version should not be put under version control. Therefore you may want to list it in the package’s top-level .gitignore file.

But you need a Makefile.am rule that will make sure that .tarball-version will exist in distribution tarballs: 

dist-hook: dist-tarball-version
.PHONY: dist-tarball-version
dist-tarball-version:
	echo '$(VERSION)' > $(distdir)/.tarball-version

Typically, the maintainer will set the version number in a clean directory (i.e. after “make distclean”). In order to adapt to alternative workflows, the file GNUmakefile, part of the Gnulib module gnumakefile, contains a rule that will print a warning or possibly call autoreconf if it finds that the version has changed but has not yet been propagated. Reminder: Not every package supports autoreconf.

Next: , Previous: , Up: Package version management   [Contents][Index]

20.8.2 Propagating the package version

At the end of a configure run, config.status is run, that creates various files with embedded pieces of information. It thus propagates the values of various variables to various files in the build tree (most notably, Makefiles and config.h).

One such propagated value is the value of the Automake-defined variable $(VERSION). (There is also the Autoconf-defined variable $(PACKAGE_VERSION), but nothing except Automake ought to use it.)

For $(VERSION) to have a sensible value, a few lines are needed in configure.ac.

The recommended code pattern is 

AC_INIT([package], [package])
AC_CONFIG_SRCDIR([unique-file-in-source-dir])
AC_CONFIG_AUX_DIR([build-aux])
VERSION_NUMBER=`cd $srcdir \
                && build-aux/git-version-gen .tarball-version`
gl_INIT_PACKAGE_VERSION([$VERSION_NUMBER])
AM_INIT_AUTOMAKE([options])

With this code pattern, the contents of the file .tarball-version and the git status are considered when configure is run.

Two older code patterns are deprecated, because they read the contents of the file .tarball-version and the git status when autoconf is run, not when configure is run. These older code patterns thus require a longer turnaround cycle when the maintainer has changed the version number.

The first such old code pattern is to set the version number directly in configure.ac: 

AC_INIT([package, version])
AC_CONFIG_SRCDIR([unique-file-in-source-dir])
AC_CONFIG_AUX_DIR([build-aux])
AM_INIT_AUTOMAKE([options])

The second such old code pattern is to invoke git-version-gen at autoconf time: 

AC_INIT([package],
        m4_esyscmd([build-aux/git-version-gen .tarball-version])])
AC_CONFIG_SRCDIR([unique-file-in-source-dir])
AC_CONFIG_AUX_DIR([build-aux])
AM_INIT_AUTOMAKE([options])

The macro gl_INIT_PACKAGE_VERSION is defined in the Gnulib module package-version.

Previous: , Up: Package version management   [Contents][Index]

20.8.3 Using the package version during the build

The unoptimized way

Once propagated through config.status, the value of $(VERSION) can appear anywhere in built files. For built files that are distributed (that is, not erased by “make distclean”), it is important to add a dependency in the Makefile.am, so that the file gets rebuilt: 

built-file: $(top_builddir)/config.status

For files that are erased by “make distclean”, this is not really necessary, because

  • In the main workflow, where the developer changes the version only between “make distclean” and “./configure”, the built files have been remade.
  • Most .o files depend on config.h, which is rebuilt when configure runs.

Thus, only in packages that don’t use Gnulib would a dependency such as 

hello-hello.$(OBJEXT): $(top_builddir)/config.status

be needed.

The optimized way

Notice that config.status usually changes much more often than the version number. Therefore, for built files which depend only on $(VERSION) and not on other variables, the following optimized technique can be used.

The technique consists of keeping a file named $(top_srcdir)/.version, which is a timestamp file. Its modification time represents the last time the value of $(VERSION) was changed. Its contents is an undocumented implementation detail.

With such a file, the dependency in Makefile.am becomes: 

built-file: $(top_srcdir)/.version

In order to prepare for using $(top_srcdir)/.version, three modifications in the package are needed:

  • In the top-level configure.ac file, add an invocation of the macro gl_CONFIG_VERSION_STAMP, near the end (before AC_OUTPUT). This macro is defined in file m4/version-stamp.m4, part of the Gnulib module version-stamp.
  • In the top-level Makefile.am, add: 
    EXTRA_DIST += $(top_srcdir)/.version
BUILT_SOURCES += $(top_srcdir)/.version

    so that the file .version will be present in tarballs and so that “make maintainer-clean” will erase it.

  • Add .version to the package’s top-level .gitignore file.

Next: , Previous: , Up: Build Infrastructure Modules   [Contents][Index]

20.9 VCS To ChangeLog

Gnulib provides the ‘vcs-to-changelog’ module to generate an output similar to the GNU ChangeLog format from metadata of source control software such as git. Here’s an example of using ‘vcs-to-changelog’: 

build-aux/vcs-to-changelog.py <from_ref> <to_ref>

where <from_ref> and <to_ref> refer to the range of commits to generate the output.

VCS To ChangeLog currently recognises changes in C source code and can traverse commits in git. Additional source frontends and source control backends may be added to the module. ‘vcs-to-changelog’ takes the following optional arguments:

  • -d: Run the parser debugger, used for debugging ‘vcs-to-changelog’
  • -q filename: Load filename as the quirks file for the project.

The quirks file is a python module that must minimally implement a get_project_quirks function that returns an object of type ProjectQuirks or its subclass. The subclass may override the following members of ProjectQuirks:

  • repo: Specify the project repo source control. The default value is git.
  • IGNORE_LIST: A list of files to ignore in the changesets, either because they are not needed (such as the ChangeLog) or because they are not parseable. For example, the GNU C Library has a header file that is only assembly code, which breaks the C parser.
  • MACRO_QUIRKS: A list of dictionary entries with indexes as orig and sub where orig is a Python regular expression pattern to match and sub is the substitution. These substitutions are used to work around C/C++ macros that are known to break parsing of C programs.
  • C_MACROS: This is a list of C preprocessor macro definitions that are extensively used and are known to break parsing due to some characteristic, mainly the lack of a semicolon at the end.

Next: , Previous: , Up: Build Infrastructure Modules   [Contents][Index]

20.10 gitlog-to-changelog

Gnulib has a module gitlog-to-changelog to parse git log output and generate ChangeLog files; see https://www.gnu.org/prep/standards/html_node/Change-Logs.html.

You can use it by extending the dist-hook rule in the top-level Makefile.am like this: 

dist-hook: gen-ChangeLog
.PHONY: gen-ChangeLog
gen-ChangeLog:
        $(AM_V_GEN)if test -e $(srcdir)/.git; then             \
          LC_ALL=en_US.UTF-8 TZ=UTC0                           \
            $(top_srcdir)/build-aux/gitlog-to-changelog        \
              --srcdir=$(srcdir) > $(distdir)/ChangeLog        \
          || exit 1;                                           \
        fi

See gitlog-to-changelog --help for complete documentation.

The LC_ALL=en_US.UTF-8 TZ=UTC0 line in this recipe assumes that you want to generate reproducible ChangeLog files that do not depend on the developer’s locale and time zone. Omit this line if you prefer ChangeLog files that depend on these developer settings.

If you wish to output the ChangeLog with dates respecting the time zone each individual commit was made in you can use the --commit-timezone option. For example: 

dist-hook: gen-ChangeLog
.PHONY: gen-ChangeLog
gen-ChangeLog:
        $(AM_V_GEN)if test -e $(srcdir)/.git; then             \
          $(top_srcdir)/build-aux/gitlog-to-changelog          \
              --srcdir=$(srcdir) --commit-timezone             \
              > $(distdir)/ChangeLog                           \
          || exit 1;                                           \
        fi

The use of --commit-timezone means that ChangeLog dates correctly represent when a committer pushed a change according to their time zone. However, as a consequence ChangeLog dates will no longer be monotonically increasing, if the developers are spread across different time zones. For example, the following three commits were made in a short period of time across two different time zones. This behavior may be undesired. 

2024-06-19  Bruno Haible  <bruno@clisp.org>

	...

2024-06-18  Collin Funk  <collin.funk1@gmail.com>

	...

2024-06-19  Bruno Haible  <bruno@clisp.org>

	...

If you wish to limit the ChangeLog entries (perhaps for size issues) to contain only entries since a particular git tag, you can use a gen-ChangeLog rule like the following: 

gen_start_ver = 8.31
gen-ChangeLog:
        $(AM_V_GEN)if test -e $(srcdir)/.git; then                 \
          log_fix='$(srcdir)/build-aux/git-log-fix';               \
          test -e "$$log_fix"                                      \
            && amend_git_log=--amend=$$log_fix                     \
            || amend_git_log=;                                     \
          { LC_ALL=en_US.UTF-8 TZ=UTC0                             \
              $(top_srcdir)/build-aux/gitlog-to-changelog          \
                --srcdir=$(srcdir)                                 \
                "$$amend_git_log" -- 'v$(gen_start_ver)~..' &&     \
            printf '\n\nSee the source repo for older entries.\n'; \
          } > $(distdir)/ChangeLog                                 \
          || exit 1;                                               \
        fi

Previous: , Up: Build Infrastructure Modules   [Contents][Index]

20.11 maintainer-makefile

Software projects are generally expected to adhere to specific coding and maintenance conventions. GNU projects in particular follow the conventions laid out in the GNU Coding Standards and Information for GNU Maintainers manuals. The Gnulib module maintainer-makefile helps automate many of these processes by providing a common framework with overridable defaults.

The module includes the files GNUmakefile (from the gnumakefile module) and maint.mk, which define several convenient targets. Each target usually comes with a description of its workings and the variables that control it. You can override variables and define rules in a file named cfg.mk, which GNUmakefile will look for. Some targets may not be relevant to your project, or may invoke programs that you do not have installed; you are not required to set all of them up.

Below is a summary of the available targets.

coverage

Generate code coverage reports.

refresh-gnulib-patches
refresh-po

Check for updates to external files.

release-commit
release
upload
web-manual-update

Automate the process of making, announcing, and distributing a new project release.

These rely on several other modules, including do-release-commit-and-tag and announce-gen, and expect a GNU-like project structure by default. For example, your project should maintain a file NEWS or NEWS.md which highlights important changes between releases, from new to old. The section for each release is introduced by a heading typically indicating its version, date, and type. Here are some examples: 

* Noteworthy changes in release 1.2 (2025-11-17) [stable]
# Noteworthy changes in release 1.2 (2025-11-17)
## Major changes in 1.2.3 (2025-11-17) [beta]
Changes in 1.2.3 (2025-11-17)

The first such heading in the file stands as a placeholder for as-yet-unreleased changes. It typically looks like a template for subsequent headings, with details replaced by question marks. For example: 

# Noteworthy changes in release ?.? (????-??-??) [?]

Though this file was traditionally named NEWS, more recent versions of Automake and Gnulib also accept NEWS.md. If the tooling infrastructure you use supports only NEWS but you would prefer to maintain a NEWS.md, you can try defining the former as a symlink to the latter. In any case, maintaining both names as distinct files can be confusing and is therefore discouraged.

See also the module readme-release, which outlines a typical GNU release process.

syntax-check

Search the project for many suspicious constructs, including unportable syntax, stale copyright notices, and misspellings.

update-copyright

Update all copyright year lists.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

21 Build Infrastructure Files

Gnulib contains also a small number of files that are not part of modules. They are meant to be imported into packages by means of ‘gnulib-tool --copy-file’, not ‘gnulib-tool --import’. For example, the commands to import the files config.guess and config.sub are 

for file in config.guess config.sub; do
  $GNULIB_TOOL --copy-file build-aux/$file \
    && chmod a+x build-aux/$file \
    || exit $?
done

Packages that don’t use Gnulib can get hold of these files through direct download from Gnulib’s git repository. The commands to do this look as follows: 

for file in config.guess config.sub; do
  echo "$0: getting $file..."
  wget -q --timeout=5 -O build-aux/$file.tmp "https://git.savannah.gnu.org/gitweb/?p=gnulib.git;a=blob_plain;f=build-aux/${file};hb=HEAD" \
    && mv build-aux/$file.tmp build-aux/$file \
    && chmod a+x build-aux/$file
  retval=$?
  rm -f build-aux/$file.tmp
  test $retval -eq 0 || exit $retval
done

Next: , Up: Build Infrastructure Files   [Contents][Index]

21.1 Recognizing platforms

build-aux/config.guess
build-aux/config.sub

These files are helper scripts, invoked by the ‘configure’ script. config.guess recognizes the platform on which the script is running, and produces a triplet of the form cpu-type-vendor-operating_system. config.sub receives a possibly abbreviated triplet and produces a canonical triplet for a platform. For more information, see https://www.gnu.org/prep/standards/html_node/Configuration.html.

It is important that you always include the newest versions of these two files in your tarball, because people who work on emerging platforms otherwise have a hard time building your package.

Next: , Previous: , Up: Build Infrastructure Files   [Contents][Index]

21.2 Utilities for Makefiles

These programs can be used in Makefiles. Some of them are also described in https://www.gnu.org/software/automake/manual/html_node/Auxiliary-Programs.html.

build-aux/ar-lib
build-aux/compile

These two scripts are necessary for supporting portability to native Windows with the MSVC compiler. compile is a wrapper script that invokes the compiler and provides a command-line interface compatible with Unix compilers. Similarly, ar-lib is a wrapper script that provides a command-line interface compatible with Unix ar.

build-aux/depcomp

This is a helper script, used by Makefile rules generated by GNU Automake. It generates Makefile dependencies while compiling a file.

build-aux/install-sh

This is a helper script, used by Makefile rules generated by GNU Automake. It installs files during the make install phase. In the Makefile, don’t use this file directly; always use $(INSTALL_PROGRAM) or $(INSTALL_DATA) instead.

build-aux/mdate-sh

This script determines the modification time of a file and pretty-prints it. The typical use is to add a “Last modified” line to the documentation.

build-aux/mkinstalldirs

This is a helper script, used by Makefile rules generated by GNU Automake. It creates directories during the make install phase. It is roughly equivalent to ‘mkdir -p’ (except that the latter is not portable). In the Makefile, don’t use this file directly; always use $(MKDIR_P) instead.

build-aux/mktempd

This script creates a temporary directory. It is roughly equivalent to ‘mktemp -d’ (except that the latter is not portable).

build-aux/move-if-change

This script moves a freshly generated file to a destination file, with a special optimization for the case that both files are identical. In this case the freshly generated file is deleted, and the time stamp of the destination file is not changed. This is useful when updating a file that rarely actually changes and which many Makefile targets depend upon.

Next: , Previous: , Up: Build Infrastructure Files   [Contents][Index]

21.3 Programs for developing in Git checkouts

These programs can help when developing in a Git checkout. The maintainer of the package copies these programs into the version control of the package, so that co-developers can use these tools right away.

top/gitsub.sh

This program manages the subdirectories of a Git checkout that come from other packages, including Gnulib.

top/bootstrap
top/autopull.sh
top/autogen.sh
top/bootstrap-funclib.sh

This is a set of three programs and a function library, that manage the source directory of a package, preparing for the state where ‘./configure’ can be used.

autopull.sh is a program for fetching dependencies that may require network accesses. It manages the Git submodules, including Gnulib – assuming that Gnulib is a Git submodule. It also can fetch the PO files for internationalized packages.

autogen.sh is a program that is meant to be run after autopull.sh. It generates all autogeneratable files that are omitted from version control. Usually this means that it invokes gnulib-tool and automake, that generate files from other files.

bootstrap is a wrapper around both: ./bootstrap --pull is equivalent to ./autopull.sh, ./bootstrap --gen is equivalent to ./autogen.sh. Plain ./bootstrap is equivalent to ./autopull.sh immediately followed by ./autogen.sh; however, because plain ./bootstrap mixes version control management and generation of files in non-obvious ways, it has a number of usability issues for the advanced developer.

bootstrap-funclib.sh is a function library for these three programs. It is not meant to be used directly.

All three programs make use of a configuration file, called bootstrap.conf.

build-aux/bootstrap

This acts like top/bootstrap, except it does not need the companion files autogen.sh, autopull.sh, and bootstrap-funclib.sh so it avoids some clutter in your project’s top level directory. With this approach, you update via ./bootstrap --pull and ./bootstrap --gen instead of via ./autopull.sh and ./autogen.sh. Otherwise this approach acts similarly, and uses the same bootstrap.conf file.

build-aux/bootstrap.conf

This is the template configuration file. After copying it into the top-level directory of your package, you need to customize it.

build-aux/po/Makefile.in.in
build-aux/po/remove-potcdate.sed

These are auxiliary files used by bootstrap. You don’t have to copy them yourself; bootstrap will do that.

Next: , Previous: , Up: Build Infrastructure Files   [Contents][Index]

21.4 Utilities for building documentation

These are auxiliary files for building documentation.

build-aux/texinfo.tex

This file is needed for the conversion of Texinfo-format documentation to PDF, PostScript, or DVI formats. It implements the GNU Texinfo commands on top of plain TeX.

build-aux/x-to-1.in

This file, once processed, gives a program x-to-1, that produces a manual page for a program, by combining a skeleton with the program’s --help output.

Next: , Previous: , Up: Build Infrastructure Files   [Contents][Index]

21.5 Utilities for building libraries

build-aux/declared.sh

This program extracts the declared global symbols of a C header file. It is useful when you want to control the set of symbols exported by a library. See Controlling the Exported Symbols of Shared Libraries.

Previous: , Up: Build Infrastructure Files   [Contents][Index]

21.6 Utilities for running test suites

build-aux/run-test

This file is a test driver that supports running a test under valgrind.

build-aux/test-driver.diff

This is a patch, against Automake’s test driver, that supports running a test suite on Android.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

22 Release Management Files

Gnulib also contains a few scripts that are useful for the release management of a package. They can be used directly off the Gnulib checkout; they don’t need to be copied first.

Next: , Up: Release Management Files   [Contents][Index]

22.1 Tools for releasing packages with shared libraries

build-aux/libtool-next-version

This program is a wizard that helps a maintainer update the libtool version of a shared library, without making mistakes in this process. For background documentation, see https://www.gnu.org/software/libtool/manual/html_node/Updating-version-info.html.

Previous: , Up: Release Management Files   [Contents][Index]

22.2 Tools for uploading release tarballs

build-aux/gnupload

This program is a user-friendly way to upload a release tarball to one of the GNU servers (ftp.gnu.org or alpha.gnu.org). It implements the interface described in https://www.gnu.org/prep/maintain/html_node/Automated-FTP-Uploads.html.

build-aux/ncftpput-ftp

This is a helper program that mimics the ncftpput program used by gnupload. If you want to use gnupload but don’t have ncftp installed, copy this file into your $PATH, renaming it to ncftpput.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

Appendix A GNU Free Documentation License

Version 1.3, 3 November 2008 
Copyright © 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.
https://fsf.org/

Everyone is permitted to copy and distribute verbatim copies
of this license document, but changing it is not allowed.
  1. PREAMBLE

    The purpose of this License is to make a manual, textbook, or other functional and useful document free in the sense of freedom: to assure everyone the effective freedom to copy and redistribute it, with or without modifying it, either commercially or noncommercially. Secondarily, this License preserves for the author and publisher a way to get credit for their work, while not being considered responsible for modifications made by others.

    This License is a kind of “copyleft”, which means that derivative works of the document must themselves be free in the same sense. It complements the GNU General Public License, which is a copyleft license designed for free software.

    We have designed this License in order to use it for manuals for free software, because free software needs free documentation: a free program should come with manuals providing the same freedoms that the software does. But this License is not limited to software manuals; it can be used for any textual work, regardless of subject matter or whether it is published as a printed book. We recommend this License principally for works whose purpose is instruction or reference.

  2. APPLICABILITY AND DEFINITIONS

    This License applies to any manual or other work, in any medium, that contains a notice placed by the copyright holder saying it can be distributed under the terms of this License. Such a notice grants a world-wide, royalty-free license, unlimited in duration, to use that work under the conditions stated herein. The “Document”, below, refers to any such manual or work. Any member of the public is a licensee, and is addressed as “you”. You accept the license if you copy, modify or distribute the work in a way requiring permission under copyright law.

    A “Modified Version” of the Document means any work containing the Document or a portion of it, either copied verbatim, or with modifications and/or translated into another language.

    A “Secondary Section” is a named appendix or a front-matter section of the Document that deals exclusively with the relationship of the publishers or authors of the Document to the Document’s overall subject (or to related matters) and contains nothing that could fall directly within that overall subject. (Thus, if the Document is in part a textbook of mathematics, a Secondary Section may not explain any mathematics.) The relationship could be a matter of historical connection with the subject or with related matters, or of legal, commercial, philosophical, ethical or political position regarding them.

    The “Invariant Sections” are certain Secondary Sections whose titles are designated, as being those of Invariant Sections, in the notice that says that the Document is released under this License. If a section does not fit the above definition of Secondary then it is not allowed to be designated as Invariant. The Document may contain zero Invariant Sections. If the Document does not identify any Invariant Sections then there are none.

    The “Cover Texts” are certain short passages of text that are listed, as Front-Cover Texts or Back-Cover Texts, in the notice that says that the Document is released under this License. A Front-Cover Text may be at most 5 words, and a Back-Cover Text may be at most 25 words.

    A “Transparent” copy of the Document means a machine-readable copy, represented in a format whose specification is available to the general public, that is suitable for revising the document straightforwardly with generic text editors or (for images composed of pixels) generic paint programs or (for drawings) some widely available drawing editor, and that is suitable for input to text formatters or for automatic translation to a variety of formats suitable for input to text formatters. A copy made in an otherwise Transparent file format whose markup, or absence of markup, has been arranged to thwart or discourage subsequent modification by readers is not Transparent. An image format is not Transparent if used for any substantial amount of text. A copy that is not “Transparent” is called “Opaque”.

    Examples of suitable formats for Transparent copies include plain ASCII without markup, Texinfo input format, LaTeX input format, SGML or XML using a publicly available DTD, and standard-conforming simple HTML, PostScript or PDF designed for human modification. Examples of transparent image formats include PNG, XCF and JPG. Opaque formats include proprietary formats that can be read and edited only by proprietary word processors, SGML or XML for which the DTD and/or processing tools are not generally available, and the machine-generated HTML, PostScript or PDF produced by some word processors for output purposes only.

    The “Title Page” means, for a printed book, the title page itself, plus such following pages as are needed to hold, legibly, the material this License requires to appear in the title page. For works in formats which do not have any title page as such, “Title Page” means the text near the most prominent appearance of the work’s title, preceding the beginning of the body of the text.

    The “publisher” means any person or entity that distributes copies of the Document to the public.

    A section “Entitled XYZ” means a named subunit of the Document whose title either is precisely XYZ or contains XYZ in parentheses following text that translates XYZ in another language. (Here XYZ stands for a specific section name mentioned below, such as “Acknowledgements”, “Dedications”, “Endorsements”, or “History”.) To “Preserve the Title” of such a section when you modify the Document means that it remains a section “Entitled XYZ” according to this definition.

    The Document may include Warranty Disclaimers next to the notice which states that this License applies to the Document. These Warranty Disclaimers are considered to be included by reference in this License, but only as regards disclaiming warranties: any other implication that these Warranty Disclaimers may have is void and has no effect on the meaning of this License.

  3. VERBATIM COPYING

    You may copy and distribute the Document in any medium, either commercially or noncommercially, provided that this License, the copyright notices, and the license notice saying this License applies to the Document are reproduced in all copies, and that you add no other conditions whatsoever to those of this License. You may not use technical measures to obstruct or control the reading or further copying of the copies you make or distribute. However, you may accept compensation in exchange for copies. If you distribute a large enough number of copies you must also follow the conditions in section 3.

    You may also lend copies, under the same conditions stated above, and you may publicly display copies.

  4. COPYING IN QUANTITY

    If you publish printed copies (or copies in media that commonly have printed covers) of the Document, numbering more than 100, and the Document’s license notice requires Cover Texts, you must enclose the copies in covers that carry, clearly and legibly, all these Cover Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on the back cover. Both covers must also clearly and legibly identify you as the publisher of these copies. The front cover must present the full title with all words of the title equally prominent and visible. You may add other material on the covers in addition. Copying with changes limited to the covers, as long as they preserve the title of the Document and satisfy these conditions, can be treated as verbatim copying in other respects.

    If the required texts for either cover are too voluminous to fit legibly, you should put the first ones listed (as many as fit reasonably) on the actual cover, and continue the rest onto adjacent pages.

    If you publish or distribute Opaque copies of the Document numbering more than 100, you must either include a machine-readable Transparent copy along with each Opaque copy, or state in or with each Opaque copy a computer-network location from which the general network-using public has access to download using public-standard network protocols a complete Transparent copy of the Document, free of added material. If you use the latter option, you must take reasonably prudent steps, when you begin distribution of Opaque copies in quantity, to ensure that this Transparent copy will remain thus accessible at the stated location until at least one year after the last time you distribute an Opaque copy (directly or through your agents or retailers) of that edition to the public.

    It is requested, but not required, that you contact the authors of the Document well before redistributing any large number of copies, to give them a chance to provide you with an updated version of the Document.

  5. MODIFICATIONS

    You may copy and distribute a Modified Version of the Document under the conditions of sections 2 and 3 above, provided that you release the Modified Version under precisely this License, with the Modified Version filling the role of the Document, thus licensing distribution and modification of the Modified Version to whoever possesses a copy of it. In addition, you must do these things in the Modified Version:

    1. Use in the Title Page (and on the covers, if any) a title distinct from that of the Document, and from those of previous versions (which should, if there were any, be listed in the History section of the Document). You may use the same title as a previous version if the original publisher of that version gives permission.
    2. List on the Title Page, as authors, one or more persons or entities responsible for authorship of the modifications in the Modified Version, together with at least five of the principal authors of the Document (all of its principal authors, if it has fewer than five), unless they release you from this requirement.
    3. State on the Title page the name of the publisher of the Modified Version, as the publisher.
    4. Preserve all the copyright notices of the Document.
    5. Add an appropriate copyright notice for your modifications adjacent to the other copyright notices.
    6. Include, immediately after the copyright notices, a license notice giving the public permission to use the Modified Version under the terms of this License, in the form shown in the Addendum below.
    7. Preserve in that license notice the full lists of Invariant Sections and required Cover Texts given in the Document’s license notice.
    8. Include an unaltered copy of this License.
    9. Preserve the section Entitled “History”, Preserve its Title, and add to it an item stating at least the title, year, new authors, and publisher of the Modified Version as given on the Title Page. If there is no section Entitled “History” in the Document, create one stating the title, year, authors, and publisher of the Document as given on its Title Page, then add an item describing the Modified Version as stated in the previous sentence.
    10. Preserve the network location, if any, given in the Document for public access to a Transparent copy of the Document, and likewise the network locations given in the Document for previous versions it was based on. These may be placed in the “History” section. You may omit a network location for a work that was published at least four years before the Document itself, or if the original publisher of the version it refers to gives permission.
    11. For any section Entitled “Acknowledgements” or “Dedications”, Preserve the Title of the section, and preserve in the section all the substance and tone of each of the contributor acknowledgements and/or dedications given therein.
    12. Preserve all the Invariant Sections of the Document, unaltered in their text and in their titles. Section numbers or the equivalent are not considered part of the section titles.
    13. Delete any section Entitled “Endorsements”. Such a section may not be included in the Modified Version.
    14. Do not retitle any existing section to be Entitled “Endorsements” or to conflict in title with any Invariant Section.
    15. Preserve any Warranty Disclaimers.

    If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document, you may at your option designate some or all of these sections as invariant. To do this, add their titles to the list of Invariant Sections in the Modified Version’s license notice. These titles must be distinct from any other section titles.

    You may add a section Entitled “Endorsements”, provided it contains nothing but endorsements of your Modified Version by various parties—for example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard.

    You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; but you may replace the old one, on explicit permission from the previous publisher that added the old one.

    The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.

  6. COMBINING DOCUMENTS

    You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers.

    The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.

    In the combination, you must combine any sections Entitled “History” in the various original documents, forming one section Entitled “History”; likewise combine any sections Entitled “Acknowledgements”, and any sections Entitled “Dedications”. You must delete all sections Entitled “Endorsements.”

  7. COLLECTIONS OF DOCUMENTS

    You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.

    You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.

  8. AGGREGATION WITH INDEPENDENT WORKS

    A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an “aggregate” if the copyright resulting from the compilation is not used to limit the legal rights of the compilation’s users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.

    If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document’s Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.

  9. TRANSLATION

    Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.

    If a section in the Document is Entitled “Acknowledgements”, “Dedications”, or “History”, the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.

  10. TERMINATION

    You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License.

    However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.

    Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.

    Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it.

  11. FUTURE REVISIONS OF THIS LICENSE

    The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See https://www.gnu.org/licenses/.

    Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License “or any later version” applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation. If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Document.

  12. RELICENSING

    “Massive Multiauthor Collaboration Site” (or “MMC Site”) means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A “Massive Multiauthor Collaboration” (or “MMC”) contained in the site means any set of copyrightable works thus published on the MMC site.

    “CC-BY-SA” means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization.

    “Incorporate” means to publish or republish a Document, in whole or in part, as part of another Document.

    An MMC is “eligible for relicensing” if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008.

    The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing.

ADDENDUM: How to use this License for your documents

To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page: 

  Copyright (C)  year  your name.
  Permission is granted to copy, distribute and/or modify this document
  under the terms of the GNU Free Documentation License, Version 1.3
  or any later version published by the Free Software Foundation;
  with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
  Texts.  A copy of the license is included in the section entitled ``GNU
  Free Documentation License''.

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “with…Texts.” line with this: 

    with the Invariant Sections being list their titles, with
    the Front-Cover Texts being list, and with the Back-Cover Texts
    being list.

If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.

If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

Appendix B Gnulib history

In the beginning, Richard Stallman maintained the regular expression engine of GNU and made it available to other GNU packages, such as sed, awk, grep, so that they could use the same engine. Recall that there was no GNU C library at the time.

A couple of years later, Jim Meyering, who was maintaining the shell utilities, the file utilities, and the text processing utilities, collected the common parts of these three packages in the same repository. Paul Eggert joined in, with code coming from a few GNU packages that he maintained, and so did Bruno Haible, with reusable code from the GNU gettext package.

As they cared for portability, many changes in the C code were accompanied by changes in the build infrastructure. Copying these changes into packages — it was all done manually — became cumbersome. So they wrote a program, called ‘gnulib-tool’, that does this job of copying the requested shared code into a particular package. This was in 2002.

Providing a substitute / override for a system function was relatively easy. Providing a substitute / override for a system header file was significantly harder, but was done successively: for stdint.h in 2004, for stdarg.h, sys/socket.h, sys/stat.h in 2006, for sys/time.h, wchar.h in 2007, and the development of the corresponding idioms took until 2010.

Unicode string modules (that make up GNU libunistring) were added in 2007–2009.

Modules for numeric functions (<math.h>) were added in 2010–2011.

Modules for container data structures were added between 2006 and 2018.

Versatile bit-set modules were added in 2018.

POSIX threads on non-POSIX platforms, as well as ISO C threads on all platforms, were added in 2019.

The posix_spawn facility was brought to completion on native Windows in 2022, providing the world’s first posix_spawn implementation for this platform.

Support for Android was added in 2023 and immediately used by GNU Emacs for Android.

Functions for working with Unicode characters in multibyte representation, based on mbrtoc32, were added in 2023.

Modules for manipulating the floating-point environment (fenv.h) were added in 2023.

The ‘gnulib-tool’ rewrite in Python, that was started by Dmitry Selyutin in 2012 but lay unfinished for many years, was completed by Collin Funk and Bruno Haible in 2024.

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

Module Index

Jump to:   _  
A   B   C   D   E   F   G   H   I   J   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y   Z  
_
_Exit_Exit
A
abort-debugStack traces
acceptaccept
accept4accept4
accessaccess
acosacos
acosfacosf
acoslacosl
agpl-3.0License Texinfo sources
alignallocaligned_alloc
alignasofalignof
alignasofstdalign.h
aligned_allocaligned_alloc
aligned-mallocaligned_alloc
aligned-mallocposix_memalign
aligned-mallocmemalign
allocaalloca.h
allocaalloca
alloca-optalloca
alloca-optalloca-opt
alphasortalphasort
announce-genmaintainer-makefile
areadlinkreadlink
areadlinkreadlinkat
areadlink-with-sizesys/stat.h
argmatchRecognizing Option Arguments
argpargp.h
argpargp_err_exit_status
argpargp_error
argpargp_failure
argpargp_help
argpargp_parse
argpargp_program_bug_address
argpargp_program_version
argpargp_program_version_hook
argpargp_state_help
argpargp_usage
argp-version-etcPrinting --version and bug-reporting information
argzargz.h
argzargz_add
argzargz_add_sep
argzargz_append
argzargz_count
argzargz_create
argzargz_create_sep
argzargz_delete
argzargz_extract
argzargz_insert
argzargz_next
argzargz_replace
argzargz_stringify
arpa_inet-harpa/inet.h
array-listOrdinary containers
array-mapOrdinary containers
array-omapOrdinary containers
array-osetOrdinary containers
array-setOrdinary containers
asinasin
asinfasinf
asinlasinl
assertassert.h
assertassert
assert-hstatic_assert
assert-hassert.h
atanatan
atan2atan2
atan2fatan2f
atanfatanf
atanlatanl
atexitatexit
atollatoll
attributeAttributes
avltree-listOrdinary containers
avltree-omapOrdinary containers
avltree-osetOrdinary containers
avltreehash-listOrdinary containers
B
basename-lgplbasename
bcopybcopy
bindbind
boolC99 features assumed
boolbool
boolstdbool.h
bsearchbsearch
btoc32btowc
btowcbtowc
byteswapbyteswap.h
byteswapbswap_16
byteswapbswap_32
byteswapbswap_64
C
c-ctypeisalnum
c-ctypeisalpha
c-ctypeisblank
c-ctypeiscntrl
c-ctypeisdigit
c-ctypeisgraph
c-ctypeislower
c-ctypeisprint
c-ctypeispunct
c-ctypeisspace
c-ctypeisupper
c-ctypeisxdigit
c-ctypetolower
c-ctypetoupper
c-ctypeisascii
c-ctypec-ctype
c-ctypeComparison of character APIs
c-snzprintfModernized printf
c-snzprintf-gnuModernized printf
c-strcasecmpc-strcasecmp
c-strcaseeqc-strcaseeq
c-strcasestrc-strcasestr
c-strncasecmpc-strncasecmp
c-strstrc-strstr
c-strtodc-strtod
c-strtodComparison of string APIs
c-strtoldc-strtold
c-strtoldComparison of string APIs
c-vaszprintfModernized printf
c-vaszprintf-gnuModernized printf
c-vsnzprintfModernized printf
c-vsnzprintf-gnuModernized printf
c-xvasprintfModernized printf
c32_apply_mappingtowctrans
c32_apply_mappingComparison of character APIs
c32_apply_type_testiswctype
c32_apply_type_testComparison of character APIs
c32_get_mappingwctrans
c32_get_mappingComparison of character APIs
c32_get_type_testwctype
c32_get_type_testComparison of character APIs
c32isalnumisalnum
c32isalnumiswalnum
c32isalnumComparison of character APIs
c32isalphaisalpha
c32isalphaiswalpha
c32isalphaComparison of character APIs
c32isblankisblank
c32isblankiswblank
c32isblankComparison of character APIs
c32iscntrliscntrl
c32iscntrliswcntrl
c32iscntrlComparison of character APIs
c32isdigitisdigit
c32isdigitiswdigit
c32isdigitComparison of character APIs
c32isgraphisgraph
c32isgraphiswgraph
c32isgraphComparison of character APIs
c32islowerislower
c32isloweriswlower
c32islowerComparison of character APIs
c32isprintisprint
c32isprintiswprint
c32isprintComparison of character APIs
c32ispunctispunct
c32ispunctiswpunct
c32ispunctComparison of character APIs
c32isspaceisspace
c32isspaceiswspace
c32isspaceComparison of character APIs
c32isupperisupper
c32isupperiswupper
c32isupperComparison of character APIs
c32isxdigitisxdigit
c32isxdigitiswxdigit
c32isxdigitComparison of character APIs
c32rtombc32rtomb
c32rtombwcrtomb
c32snrtombswcsnrtombs
c32snrtombsComparison of string APIs
c32srtombswcsrtombs
c32srtombsComparison of string APIs
c32stombswcstombs
c32stombsComparison of string APIs
c32swidthwcswidth
c32swidthComparison of string APIs
c32tobwctob
c32tolowertolower
c32tolowertowlower
c32tolowerComparison of character APIs
c32tolowerComparison of character APIs
c32touppertoupper
c32touppertowupper
c32toupperComparison of character APIs
c32toupperComparison of character APIs
c32widthwcwidth
c32widthComparison of character APIs
call_oncestdlib.h
call_oncecall_once
calloc-gnucalloc
calloc-posixcalloc
canonicalize-lgplrealpath
canonicalize-lgplcanonicalize_file_name
carray-listOrdinary containers
cbrtcbrt
cbrt-ieeecbrt
cbrtfcbrtf
cbrtf-ieeecbrtf
cbrtlcbrtl
cbrtl-ieeecbrtl
ceilceil
ceil-ieeeceil
ceilfceilf
ceilf-ieeeceilf
ceillceill
ceill-ieeeceill
chdirchdir
check-versionLibrary version handling
chmodchmod
chownchown
clean-tempmkostemp
clean-tempmkstemp
clean-tempmkostemps
clean-tempmkstemps
closeclose
closedirclosedir
cndcnd_broadcast
cndcnd_destroy
cndcnd_init
cndcnd_signal
cndcnd_timedwait
cndcnd_wait
cndISO C multithreading
condGnulib multithreading
configmakeconfigmake
connectconnect
copy-file-rangecopy_file_range
copysigncopysign
copysignfcopysignf
copysignlcopysignl
coscos
cosfcosf
coshcosh
coshfcoshf
coslcosl
creatcreat
crypto/gc-randomgetentropy
crypto/gc-randomgetrandom
ctimectime
ctypeisalnum
ctypeisalpha
ctypeiscntrl
ctypeisdigit
ctypeisgraph
ctypeislower
ctypeisprint
ctypeispunct
ctypeisspace
ctypeisupper
ctypeisxdigit
ctypetolower
ctypetoupper
ctypetoascii
ctype-hctype.h
D
dirent-hdirent.h
dirent-saferClosed standard fds
dirfddirfd
dirnamelibgen.h
dirnamedirname
do-release-commit-and-tagmaintainer-makefile
dprintfdprintf
dprintf-gnudprintf
dprintf-posixdprintf
dupdup
dup2dup2
dup3dup3
duplocaleduplocale
dzprintfModernized printf
dzprintf-gnuModernized printf
dzprintf-posixModernized printf
E
endianendian.h
endianbe16toh
endianbe32toh
endianbe64toh
endianhtobe16
endianhtobe32
endianhtobe64
endianhtole16
endianhtole32
endianhtole64
endianle16toh
endianle32toh
endianle64toh
environenviron
erferf
erfcerfc
errno-herrno.h
errorerror
errorerror_at_line
errorerror_message_count
errorerror_one_per_line
errorerror_print_progname
error-herror.h
euidaccesseuidaccess
execinfoexecinfo.h
execinfobacktrace
execinfobacktrace_symbols
execinfobacktrace_symbols_fd
execlexecl
execleexecle
execlpexeclp
execvexecv
execveexecve
execvpexecvp
execvpeexecvpe
expexp
exp-ieeeexp
exp2exp2
exp2-ieeeexp2
exp2fexp2f
exp2f-ieeeexp2f
exp2lexp2l
exp2l-ieeeexp2l
expfexpf
expf-ieeeexpf
explexpl
expl-ieeeexpl
explicit_bzeroexplicit_bzero
expm1expm1
expm1-ieeeexpm1
expm1fexpm1f
expm1f-ieeeexpm1f
expm1lexpm1l
expm1l-ieeeexpm1l
extensionsreaddir_r
extensionsgetgrgid_r
extensionsgetgrnam_r
extensionsgetpwnam_r
extensionsgetpwuid_r
extensionssigwait
extensionsasctime_r
extensionsctime_r
extern-inlineextern inline
F
fabsfabs
fabs-ieeefabs
fabsffabsf
fabsf-ieeefabsf
fabslfabsl
fabsl-ieeefabsl
faccessatfaccessat
fbufmodeAccessing the write buffer
fchdiropen
fchdirfchdir
fchmodatfchmodat
fchownatfchownat
fclosefclose
fcntlfcntl
fcntl-hfcntl.h
fcntl-saferClosed standard fds
fdatasyncfdatasync
fdopenfdopen
fdopendirfdopendir
fdutimensatutimensat
fdutimensatfutimesat
fenv-environmentfegetenv
fenv-environmentfeholdexcept
fenv-environmentfesetenv
fenv-environmentfeupdateenv
fenv-exceptions-state-c23fetestexceptflag
fenv-exceptions-state-c99fegetexceptflag
fenv-exceptions-state-c99fesetexceptflag
fenv-exceptions-tracking-c23fesetexcept
fenv-exceptions-tracking-c99feclearexcept
fenv-exceptions-tracking-c99feraiseexcept
fenv-exceptions-tracking-c99fetestexcept
fenv-exceptions-trappingfedisableexcept
fenv-exceptions-trappingfeenableexcept
fenv-exceptions-trappingfegetexcept
fenv-hfenv.h
fenv-roundingfegetround
fenv-roundingfesetround
fflushfflush
ffsffs
ffslffsl
ffsllffsll
flexmemberC99 features assumed
float-hfloat.h
flockflock
floorfloor
floor-ieeefloor
floorffloorf
floorf-ieeefloorf
floorlfloorl
floorl-ieeefloorl
fmafma
fma-ieeefma
fmaffmaf
fmaf-ieeefmaf
fmalfmal
fmal-ieeefmal
fmodfmod
fmod-ieeefmod
fmodffmodf
fmodf-ieeefmodf
fmodlfmodl
fmodl-ieeefmodl
fnmatchfnmatch
fnmatch-gnufnmatch.h
fnmatch-gnufnmatch
fnmatch-hfnmatch.h
fopenfopen
fopen-gnufopen
fopen-saferClosed standard fds
forkptyforkpty
fpendingAccessing the write buffer
fprintf-gnufprintf
fprintf-posixfprintf
fpurgeDropping the buffer contents
freadableState of a stream
freadaheadAccessing the read buffer
freadingState of a stream
freadptrAccessing the read buffer
freadseekAccessing the read buffer
free-posixfree
freelocalefreelocale
freopenfreopen
freopen-saferfreopen
freopen-saferClosed standard fds
frexpfrexp
frexp-ieeefrexp
frexpffrexpf
frexpf-ieeefrexpf
frexplfrexpl
frexpl-ieeefrexpl
fseekfseek
fseekofseeko
fseterrError in a stream
fstatfstat
fstatatfstatat
fsusagestatvfs
fsyncfsync
ftellftell
ftelloftello
ftellostderr
ftellostdout
ftruncateftruncate
ftsftw
ftsfts.h
ftsfts_children
ftsfts_close
ftsfts_open
ftsfts_read
ftsfts_set
funcC99 features assumed
funcfunc
futimensfutimens
fwritableState of a stream
fwritingState of a stream
fzprintfModernized printf
fzprintf-gnuModernized printf
fzprintf-posixModernized printf
G
gcdgcd
getaddrinfofreeaddrinfo
getaddrinfogai_strerror
getaddrinfogetaddrinfo
getaddrinfogetnameinfo
getaddrinfoWindows sockets
getcwdgetcwd
getcwd-lgplgetcwd
getdelimgetdelim
getdomainnamegetdomainname
getdtablesizegetdtablesize
getentropygetentropy
getentropygetrandom
getgroupsgetgroups
gethostnamelimits.h
gethostnamegethostname
getlinegetline
getloadavggetloadavg
getlocalename_l-simplegetlocalename_l
getlogingetlogin
getlogin_rgetlogin_r
getopt-gnugetopt
getopt-gnugetopt.h
getopt-gnugetopt_long
getopt-gnugetopt_long_only
getopt-posixgetopt
getpagesizegetpagesize
getpassgetpass
getpass-gnugetpass
getpayloadgetpayload
getpayloadfgetpayloadf
getpayloadlgetpayloadl
getpeernamegetpeername
getprognameprogname and getprogname
getrandomgetentropy
getrandomgetrandom
getrusagegetrusage
getsocknamegetsockname
getsockoptgetsockopt
getsuboptgetsubopt
gettextgettextize and autopoint
gettextlibintl.h
gettext-hgettextize and autopoint
gettimeclock_gettime
gettimegettimeofday
gettime-resclock_getres
gettime-restimespec_getres
gettimeofdaygettimeofday
getugroupsgetgrouplist
getumaskgetumask
getusershellendusershell
getusershellgetusershell
getusershellsetusershell
git-version-genSetting the package version
gitlog-to-changeloggitlog-to-changelog
globglob
globglobfree
globglob_pattern_p
glob-hglob.h
gnumakefileSetting the package version
gnumakefilemaintainer-makefile
gnuploadFor uploading releases
gpl-2.0License Texinfo sources
gpl-3.0License Texinfo sources
grantptgrantpt
group-membergroup_member
H
hamtSpecialized containers
hash-mapOrdinary containers
hash-setOrdinary containers
hasmntopthasmntopt
havelibSearching for Libraries
htonlhtonl
htonlhtons
htonlntohl
htonlntohs
hypothypot
hypot-ieeehypot
hypotfhypotf
hypotf-ieeehypotf
hypotlhypotl
hypotl-ieeehypotl
I
iconvVarious Kinds of Modules
iconviconv.h
iconviconv
iconviconv_close
iconviconv_open
iconv_openiconv_open
iconv_open-utficonv_open
ieee754-hieee754.h
ilogbilogb
ilogbfilogbf
ilogblilogbl
imaxabsimaxabs
imaxdivimaxdiv
inet_ntopinet_ntop
inet_ptoninet_pton
inlinestatic inline
intpropsInteger Properties
inttypes-hinttypes.h
ioctlioctl
isalnum_lisalnum_l
isalpha_lisalpha_l
isattyisatty
isblankisblank
isblankComparison of character APIs
isblank_lisblank_l
iscntrl_liscntrl_l
isdigit_lisdigit_l
isfiniteisfinite
isgraph_lisgraph_l
isinfisinf
islower_lislower_l
isnanisnan
isnanfisnanf
isnanlisnanl
isprint_lisprint_l
ispunct_lispunct_l
isspace_lisspace_l
isupper_lisupper_l
iswblankiswblank
iswblankComparison of character APIs
iswctypeiswctype
iswctypeComparison of character APIs
iswdigitiswdigit
iswdigitComparison of character APIs
iswpunctiswpunct
iswpunctComparison of character APIs
iswxdigitiswxdigit
iswxdigitComparison of character APIs
isxdigit_lisxdigit_l
J
j0j0
j1j1
jnjn
L
langinfo-hlanginfo.h
largefilesys/types.h
largefileAvoiding the year 2038 problem
lchmodlchmod
lchownlchown
ldexpldexp
ldexp-ieeeldexp
ldexpfldexpf
ldexpf-ieeeldexpf
ldexplldexpl
ldexpl-ieeeldexpl
lgammalgamma
lgpl-2.1License Texinfo sources
lgpl-3.0License Texinfo sources
lib-msvc-compatVisual Studio Compatibility
lib-symbol-versionsLD Version Scripts
lib-symbol-visibilityExported Symbols of Shared Libraries
libunistringHow to use libunistring
libunistring-optionalHow to use libunistring
limits-hlimits.h
linklink
linkatlinkat
linked-listOrdinary containers
linkedhash-listOrdinary containers
linkedhash-mapOrdinary containers
linkedhash-setOrdinary containers
listOrdinary containers
listOrdinary containers
list-c++Ordinary containers
listenlisten
localcharset<uniconv.h> modules
locale-hlocale.h
localeconvlocaleconv
localtimelocaltime
lockGnulib multithreading
loglog
log-ieeelog
log10log10
log10-ieeelog10
log10flog10f
log10f-ieeelog10f
log10llog10l
log10l-ieeelog10l
log1plog1p
log1p-ieeelog1p
log1pflog1pf
log1pf-ieeelog1pf
log1pllog1pl
log1pl-ieeelog1pl
log2log2
log2-ieeelog2
log2flog2f
log2f-ieeelog2f
log2llog2l
log2l-ieeelog2l
logblogb
logb-ieeelogb
logbflogbf
logbf-ieeelogbf
logbllogbl
logbl-ieeelogbl
logflogf
logf-ieeelogf
login_ttylogin_tty
logllogl
logl-ieeelogl
logp1logp1
logp1flogp1f
logp1llogp1l
lseeklseek
lstatlstat
M
maintainer-makefileVarious Kinds of Modules
maintainer-makefilemaintainer-makefile
malloc-gnumalloc
malloc-hmalloc.h
malloc-posixmalloc
manywarningswarnings
manywarningsmanywarnings
mapOrdinary containers
mapOrdinary containers
map-c++Ordinary containers
math-hmath.h
mbcharisalnum
mbcharisalpha
mbcharisblank
mbchariscntrl
mbcharisdigit
mbcharisgraph
mbcharislower
mbcharisprint
mbcharispunct
mbcharisspace
mbcharisupper
mbcharisxdigit
mbcharisascii
mbcharComparison of character APIs
mbfileReading multibyte strings
mbiterIterating through strings
mbiterfIterating through strings
mbrlenmbrlen
mbrtoc16mbrtoc16
mbrtoc32mbrtoc32
mbrtoc32mbrtowc
mbrtoc32-regularmbrtoc32
mbrtowcmbrtowc
mbs_endswithComparison of string APIs
mbs_startswithComparison of string APIs
mbscasecmpstrcasecmp
mbscasecmpc-strcasecmp
mbscasecmpComparison of string APIs
mbscasestrc-strcasestr
mbscasestrComparison of string APIs
mbschrstrchr
mbschrComparison of string APIs
mbscspnstrcspn
mbscspnComparison of string APIs
mbsinitmbsinit
mbslenComparison of string APIs
mbsncasecmpstrncasecmp
mbsncasecmpc-strncasecmp
mbsncasecmpComparison of string APIs
mbsnlenComparison of string APIs
mbsnrtoc32smbsnrtowcs
mbsnrtoc32sComparison of string APIs
mbsnrtowcsmbsnrtowcs
mbsnrtowcsComparison of string APIs
mbspbrkstrpbrk
mbspbrkComparison of string APIs
mbspcasecmpstrncasecmp
mbspcasecmpc-strncasecmp
mbspcasecmpComparison of string APIs
mbsrchrstrrchr
mbsrchrComparison of string APIs
mbsrtoc32smbsrtowcs
mbsrtoc32sComparison of string APIs
mbsrtowcsmbsrtowcs
mbsrtowcsComparison of string APIs
mbssepComparison of string APIs
mbsspnstrspn
mbsspnComparison of string APIs
mbsstrstrstr
mbsstrc-strstr
mbsstrComparison of string APIs
mbstoc32smbstowcs
mbstoc32sComparison of string APIs
mbstok_rstrtok_r
mbstok_rComparison of string APIs
mbstowcsmbstowcs
mbstowcsComparison of string APIs
mbswidthComparison of string APIs
mbtowcmbtowc
mbuiterIterating through strings
mbuiterfIterating through strings
mcelIterating through strings
mcel-preferIterating through strings
memalignmemalign
memccpymemccpy
memchrmemchr
memcmpmemcmp
memcpymemcpy
memmemmemmem
memmem-simplememmem
memmovememmove
mempcpymempcpy
memrchrmemrchr
memsetmemset
memset_explicitmemset_explicit
mgetgroupsgetgroups
mgetgroupsinitgroups
mkdirmkdir
mkdiratmkdirat
mkdtempmkdtemp
mkfifomkfifo
mkfifoatmkfifoat
mkfifoatmknodat
mknodmknod
mkostempmkostemp
mkostempsmkostemps
mkstempmkstemp
mkstempsmkstemps
mktimemktime
mntent-hmntent.h
modfmodf
modf-ieeemodf
modffmodff
modff-ieeemodff
modflmodfl
modfl-ieeemodfl
monetary-hmonetary.h
mountlistmntent.h
mtxmtx_destroy
mtxmtx_init
mtxmtx_lock
mtxmtx_timedlock
mtxmtx_trylock
mtxmtx_unlock
mtxISO C multithreading
N
nanosleepnanosleep
net_if-hnet/if.h
netdb-hnetdb.h
netinet_in-hnetinet/in.h
newlocalenewlocale
nextafternextafter
nl_langinfonl_langinfo
nonblockingfcntl.h
nonblockingopen
nonblockingfgetc
nonblockingfgets
nonblockingfprintf
nonblockingfputc
nonblockingfputs
nonblockingfread
nonblockingfscanf
nonblockingfwrite
nonblockinggetc
nonblockinggetchar
nonblockingprintf
nonblockingputc
nonblockingputchar
nonblockingputs
nonblockingscanf
nonblockingvfprintf
nonblockingvfscanf
nonblockingvprintf
nonblockingvscanf
nonblockingpipe2
nonblockingread
nonblockingwrite
noreturnNon-returning Functions
nprocget_nprocs
nstrftimestrftime
nullptrnullptr
O
obstackobstack.h
obstack-printfobstack_printf
obstack-printfobstack_vprintf
obstack-printf-gnuobstack_printf
obstack-printf-gnuobstack_vprintf
obstack-printf-posixobstack_printf
obstack-printf-posixobstack_vprintf
obstack-zprintfModernized printf
obstack-zprintf-gnuModernized printf
obstack-zprintf-posixModernized printf
omapOrdinary containers
omapOrdinary containers
omap-c++Ordinary containers
onceGnulib multithreading
openopen
openatopenat
openat-saferClosed standard fds
openat2openat2
opendiropendir
openmpMultithreading
openptyposix_openpt
openptyopenpty
optionsgetopt_long
osetOrdinary containers
osetOrdinary containers
oset-c++Ordinary containers
P
package-versionPropagating the package version
pagealign_allocaligned_alloc
pagealign_allocposix_memalign
parse-datetimegetdate
pathmaxlimits.h
pclosepclose
perrorperror
pipe-posixpipe
pipe2pipe2
pipe2-saferClosed standard fds
pollpoll
poll-hpoll.h
popenpopen
popen-saferClosed standard fds
posix_memalignposix_memalign
posix_openptposix_openpt
posix_spawnposix_spawn
posix_spawn_file_actions_addchdirposix_spawn
posix_spawn_file_actions_addchdirposix_spawnp
posix_spawn_file_actions_addchdirposix_spawn_file_actions_addchdir_np
posix_spawn_file_actions_addcloseposix_spawn_file_actions_addclose
posix_spawn_file_actions_adddup2posix_spawn_file_actions_adddup2
posix_spawn_file_actions_addfchdirposix_spawn
posix_spawn_file_actions_addfchdirposix_spawnp
posix_spawn_file_actions_addfchdirposix_spawn_file_actions_addfchdir_np
posix_spawn_file_actions_addopenposix_spawn_file_actions_addopen
posix_spawn_file_actions_destroyposix_spawn_file_actions_destroy
posix_spawn_file_actions_initposix_spawn_file_actions_init
posix_spawnattr_destroyposix_spawnattr_destroy
posix_spawnattr_getflagsposix_spawnattr_getflags
posix_spawnattr_getpgroupposix_spawnattr_getpgroup
posix_spawnattr_getschedparamposix_spawnattr_getschedparam
posix_spawnattr_getschedpolicyposix_spawnattr_getschedpolicy
posix_spawnattr_getsigdefaultposix_spawnattr_getsigdefault
posix_spawnattr_getsigmaskposix_spawnattr_getsigmask
posix_spawnattr_initposix_spawnattr_init
posix_spawnattr_setflagsposix_spawnattr_setflags
posix_spawnattr_setpgroupposix_spawnattr_setpgroup
posix_spawnattr_setschedparamposix_spawnattr_setschedparam
posix_spawnattr_setschedpolicyposix_spawnattr_setschedpolicy
posix_spawnattr_setsigdefaultposix_spawnattr_setsigdefault
posix_spawnattr_setsigmaskposix_spawnattr_setsigmask
posix_spawnpposix_spawnp
posixcheckFinding POSIX substitutes
powpow
powfpowf
preadpread
printf-gnuprintf
printf-posixprintf
printf-with-n-directivedprintf
printf-with-n-directivefprintf
printf-with-n-directiveprintf
printf-with-n-directivesnprintf
printf-with-n-directivesprintf
printf-with-n-directivevdprintf
printf-with-n-directivevfprintf
printf-with-n-directivevprintf
printf-with-n-directivevsnprintf
printf-with-n-directivevsprintf
printf-with-n-directiveobstack_printf
printf-with-n-directiveobstack_vprintf
prognameprogname and getprogname
pselectpselect
pthreadPOSIX multithreading
pthread_mutex_timedlockpthread_mutex_timedlock
pthread_sigmaskpthread_sigmask
pthread-condpthread_cond_broadcast
pthread-condpthread_cond_destroy
pthread-condpthread_cond_init
pthread-condpthread_cond_signal
pthread-condpthread_cond_timedwait
pthread-condpthread_cond_wait
pthread-condpthread_condattr_destroy
pthread-condpthread_condattr_init
pthread-condPOSIX multithreading
pthread-hpthread.h
pthread-mutexpthread_mutex_destroy
pthread-mutexpthread_mutex_init
pthread-mutexpthread_mutex_lock
pthread-mutexpthread_mutex_trylock
pthread-mutexpthread_mutex_unlock
pthread-mutexpthread_mutexattr_destroy
pthread-mutexpthread_mutexattr_getrobust
pthread-mutexpthread_mutexattr_gettype
pthread-mutexpthread_mutexattr_init
pthread-mutexpthread_mutexattr_setrobust
pthread-mutexpthread_mutexattr_settype
pthread-mutexPOSIX multithreading
pthread-oncepthread_once
pthread-oncePOSIX multithreading
pthread-rwlockpthread_rwlock_destroy
pthread-rwlockpthread_rwlock_init
pthread-rwlockpthread_rwlock_rdlock
pthread-rwlockpthread_rwlock_timedrdlock
pthread-rwlockpthread_rwlock_timedwrlock
pthread-rwlockpthread_rwlock_tryrdlock
pthread-rwlockpthread_rwlock_trywrlock
pthread-rwlockpthread_rwlock_unlock
pthread-rwlockpthread_rwlock_wrlock
pthread-rwlockpthread_rwlockattr_destroy
pthread-rwlockpthread_rwlockattr_init
pthread-rwlockPOSIX multithreading
pthread-spinpthread_spin_destroy
pthread-spinpthread_spin_init
pthread-spinpthread_spin_lock
pthread-spinpthread_spin_trylock
pthread-spinpthread_spin_unlock
pthread-spinPOSIX multithreading
pthread-threadpthread_attr_destroy
pthread-threadpthread_attr_getdetachstate
pthread-threadpthread_attr_init
pthread-threadpthread_attr_setdetachstate
pthread-threadpthread_create
pthread-threadpthread_detach
pthread-threadpthread_equal
pthread-threadpthread_exit
pthread-threadpthread_join
pthread-threadpthread_self
pthread-threadPOSIX multithreading
pthread-tsspthread_getspecific
pthread-tsspthread_key_create
pthread-tsspthread_key_delete
pthread-tsspthread_setspecific
pthread-tssPOSIX multithreading
ptsnameptsname
ptsname_rptsname
ptsname_rptsname_r
pty-hpty.h
putenv-gnuputenv
pwritepwrite
Q
qsortqsort
qsort_rqsort_r
quoteQuoting
quoteargQuoting
R
raiseraise
randrand
randominitstate
randomrandom
randomsetstate
randomsrandom
random_rrand_r
random_rinitstate_r
random_rrandom_r
random_rsetstate_r
random_rsrandom_r
rawmemchrrawmemchr
rbtree-listOrdinary containers
rbtree-omapOrdinary containers
rbtree-osetOrdinary containers
rbtreehash-listOrdinary containers
readread
readdirreaddir
readlineVarious Kinds of Modules
readlinkreadlink
readlinkatreadlinkat
readme-releasemaintainer-makefile
readutmputmpx.h
readutmputmp.h
readutmpgetutmp
readutmpgetutmpx
realloc-posixrealloc
reallocarrayreallocarray
recvrecv
recvfromrecvfrom
regexregex.h
regexregcomp
regexregerror
regexregexec
regexregfree
relocatable-libSupporting Relocation
relocatable-lib-lgplSupporting Relocation
relocatable-perlSupporting Relocation
relocatable-progSupporting Relocation
relocatable-scriptSupporting Relocation
remainderremainder
remainder-ieeeremainder
remainderfremainderf
remainderf-ieeeremainderf
remainderlremainderl
remainderl-ieeeremainderl
removeremove
renamerename
renameatrenameat
renameaturenameat2
rewinddirrewinddir
rintrint
rint-ieeerint
rintfrintf
rintf-ieeerintf
rintlrintl
rintl-ieeerintl
rmdirrmdir
roundround
round-ieeeround
roundfroundf
roundf-ieeeroundf
roundlroundl
roundl-ieeeroundl
rpmatchrpmatch
S
safe-allocSafe Allocation Macros
safe-readread
safe-writewrite
same-inodesys/stat.h
scandirscandir
sched_yieldsched_yield
sched_yieldPOSIX multithreading
sched-hsched.h
search-hsearch.h
secure_getenvsecure_getenv
selectselect
selinux-hfgetfilecon
selinux-hgetfilecon
selinux-hlgetfilecon
sendsend
sendtosendto
serventgetservbyname
serventgetservbyport
setOrdinary containers
setOrdinary containers
set-c++Ordinary containers
setenvsetenv
sethostnamesethostname
setlocalesetlocale
setlocale-nullsetlocale
setpayloadsetpayload
setpayloadfsetpayloadf
setpayloadlsetpayloadl
setpayloadsigsetpayloadsig
setpayloadsigfsetpayloadsigf
setpayloadsiglsetpayloadsigl
setsockoptsetsockopt
sf-istreamfmemopen
shutdownshutdown
sig2strsig2str
sig2strstr2sig
sig2strsigabbrev_np
sigabbrev_npsigabbrev_np
sigactionsigaction
sigdescr_npsigdescr_np
signal-hsignal.h
signbitsignbit
sigpipefprintf
sigpipefputc
sigpipefputs
sigpipefwrite
sigpipeprintf
sigpipeputc
sigpipeputchar
sigpipeputs
sigpipevfprintf
sigpipevprintf
sigpipewrite
sigprocmasksigaddset
sigprocmasksigdelset
sigprocmasksigemptyset
sigprocmasksigfillset
sigprocmasksigismember
sigprocmasksigpending
sigprocmasksigprocmask
sinsin
sinfsinf
sinhsinh
sinhfsinhf
sinlsinl
sleepsleep
snprintfsnprintf
snprintf-gnusnprintf
snprintf-posixsnprintf
snzprintfModernized printf
snzprintf-gnuModernized printf
snzprintf-posixModernized printf
socketsocket
spawn-hspawn.h
spinGnulib multithreading
sprintf-gnusprintf
sprintf-posixsprintf
sqrtsqrt
sqrt-ieeesqrt
sqrtfsqrtf
sqrtf-ieeesqrtf
sqrtlsqrtl
sqrtl-ieeesqrtl
stack-traceStack traces
statstat
stat-sizestat-size
stat-timesys/stat.h
stdalign-hstdalign.h
stdarg-hstdarg.h
stdarg-hva_copy
stdbitstdbit.h
stdbool-h-c99stdbool.h
stdc_bit_ceilstdc_bit_ceil
stdc_bit_floorstdc_bit_floor
stdc_bit_widthstdc_bit_width
stdc_count_onesstdc_count_ones
stdc_count_zerosstdc_count_zeros
stdc_first_leading_onestdc_first_leading_one
stdc_first_leading_zerostdc_first_leading_zero
stdc_first_trailing_onestdc_first_trailing_one
stdc_first_trailing_zerostdc_first_trailing_zero
stdc_has_single_bitstdc_has_single_bit
stdc_leading_onesstdc_leading_ones
stdc_leading_zerosstdc_leading_zeros
stdc_load8stdc_load8_bes8
stdc_load8stdc_load8_bes16
stdc_load8stdc_load8_bes32
stdc_load8stdc_load8_bes64
stdc_load8stdc_load8_beu8
stdc_load8stdc_load8_beu16
stdc_load8stdc_load8_beu32
stdc_load8stdc_load8_beu64
stdc_load8stdc_load8_les8
stdc_load8stdc_load8_les16
stdc_load8stdc_load8_les32
stdc_load8stdc_load8_les64
stdc_load8stdc_load8_leu8
stdc_load8stdc_load8_leu16
stdc_load8stdc_load8_leu32
stdc_load8stdc_load8_leu64
stdc_load8_alignedstdc_load8_aligned_bes8
stdc_load8_alignedstdc_load8_aligned_bes16
stdc_load8_alignedstdc_load8_aligned_bes32
stdc_load8_alignedstdc_load8_aligned_bes64
stdc_load8_alignedstdc_load8_aligned_beu8
stdc_load8_alignedstdc_load8_aligned_beu16
stdc_load8_alignedstdc_load8_aligned_beu32
stdc_load8_alignedstdc_load8_aligned_beu64
stdc_load8_alignedstdc_load8_aligned_les8
stdc_load8_alignedstdc_load8_aligned_les16
stdc_load8_alignedstdc_load8_aligned_les32
stdc_load8_alignedstdc_load8_aligned_les64
stdc_load8_alignedstdc_load8_aligned_leu8
stdc_load8_alignedstdc_load8_aligned_leu16
stdc_load8_alignedstdc_load8_aligned_leu32
stdc_load8_alignedstdc_load8_aligned_leu64
stdc_memreverse8stdc_memreverse8
stdc_memreverse8ustdc_memreverse8u8
stdc_memreverse8ustdc_memreverse8u16
stdc_memreverse8ustdc_memreverse8u32
stdc_memreverse8ustdc_memreverse8u64
stdc_rotate_leftstdc_rotate_left
stdc_rotate_rightstdc_rotate_right
stdc_store8stdc_store8_bes8
stdc_store8stdc_store8_bes16
stdc_store8stdc_store8_bes32
stdc_store8stdc_store8_bes64
stdc_store8stdc_store8_beu8
stdc_store8stdc_store8_beu16
stdc_store8stdc_store8_beu32
stdc_store8stdc_store8_beu64
stdc_store8stdc_store8_les8
stdc_store8stdc_store8_les16
stdc_store8stdc_store8_les32
stdc_store8stdc_store8_les64
stdc_store8stdc_store8_leu8
stdc_store8stdc_store8_leu16
stdc_store8stdc_store8_leu32
stdc_store8stdc_store8_leu64
stdc_store8_alignedstdc_store8_aligned_bes8
stdc_store8_alignedstdc_store8_aligned_bes16
stdc_store8_alignedstdc_store8_aligned_bes32
stdc_store8_alignedstdc_store8_aligned_bes64
stdc_store8_alignedstdc_store8_aligned_beu8
stdc_store8_alignedstdc_store8_aligned_beu16
stdc_store8_alignedstdc_store8_aligned_beu32
stdc_store8_alignedstdc_store8_aligned_beu64
stdc_store8_alignedstdc_store8_aligned_les8
stdc_store8_alignedstdc_store8_aligned_les16
stdc_store8_alignedstdc_store8_aligned_les32
stdc_store8_alignedstdc_store8_aligned_les64
stdc_store8_alignedstdc_store8_aligned_leu8
stdc_store8_alignedstdc_store8_aligned_leu16
stdc_store8_alignedstdc_store8_aligned_leu32
stdc_store8_alignedstdc_store8_aligned_leu64
stdc_trailing_onesstdc_trailing_ones
stdc_trailing_zerosstdc_trailing_zeros
stdckdint-hstdckdint.h
stdckdint-hWraparound Arithmetic
stdcountof-hstdcountof.h
stddef-hstddef.h
stdint-hC99 features assumed
stdint-hstdint.h
stdio-hstdio.h
stdio-hfgetc
stdio-hfgets
stdio-hfprintf
stdio-hfputc
stdio-hfputs
stdio-hfread
stdio-hfscanf
stdio-hfwrite
stdio-hgetc
stdio-hgetchar
stdio-hprintf
stdio-hputc
stdio-hputchar
stdio-hputs
stdio-hscanf
stdio-hvfprintf
stdio-hvprintf
stdio-hread
stdlib-hstdlib.h
stdlib-hexit
stdlib-saferClosed standard fds
stdnoreturn-hstdnoreturn.h
stdnoreturn-hNon-returning Functions
stpcpystpcpy
stpcpyComparison of string APIs
stpncpystpncpy
stpncpyComparison of string APIs
str_endswithComparison of string APIs
str_startswithComparison of string APIs
strcasecmpstrcasecmp
strcasecmpComparison of string APIs
strcasecmp_lstrcasecmp_l
strcasestrstrcasestr
strcasestrComparison of string APIs
strcasestr-simplestrcasestr
strchrnulstrchrnul
strcspnstrcspn
strcspnComparison of string APIs
strdupstrdup
strdupComparison of string APIs
strdup-posixstrdup
strerrorstrerror
strerror_lstrerror_l
strerror_r-posixstrerror_r
strerrorname_npstrerrorname_np
strfmon_lstrfmon_l
strftime-fixesstrftime
striconviconv
striconvehiconv
striconvehiconv_open
string-bufferopen_memstream
string-descComparison of string APIs
string-descHandling strings with NUL characters
string-desc-quoteargHandling strings with NUL characters
string-hstring.h
string-hstrcat
string-hstrcpy
string-hstrncpy
strings-hstrings.h
strncasecmpstrncasecmp
strncasecmpComparison of string APIs
strncasecmp_lstrncasecmp_l
strncatstrncat
strncatComparison of string APIs
strncmpstrncmp
strncpystrncpy
strndupstrndup
strndupComparison of string APIs
strnlenstrnlen
strnlenComparison of string APIs
strpbrkstrpbrk
strpbrkComparison of string APIs
strptimestrptime
strsepstrsep
strsepComparison of string APIs
strsignalstrsignal
strstrstrstr
strstrComparison of string APIs
strstr-simplestrstr
strtodstrtod
strtodComparison of string APIs
strtod-obsoletestrtod
strtofstrtof
strtofComparison of string APIs
strtoimaxstrtoimax
strtoimaxComparison of string APIs
strtok_rstrtok_r
strtok_rComparison of string APIs
strtolstrtol
strtolComparison of string APIs
strtoldstrtold
strtoldComparison of string APIs
strtollstrtoll
strtollComparison of string APIs
strtoulstrtoul
strtoulComparison of string APIs
strtoullstrtoull
strtoullComparison of string APIs
strtoumaxstrtoumax
strtoumaxComparison of string APIs
strverscmpstrverscmp
sublistOrdinary containers
symlinksymlink
symlinkatsymlinkat
sys_file-hsys/file.h
sys_ioctl-hsys/ioctl.h
sys_msg-hsys/msg.h
sys_random-hsys/random.h
sys_resource-hsys/resource.h
sys_select-hsys/select.h
sys_sem-hsys/sem.h
sys_shm-hsys/shm.h
sys_socket-hsys/socket.h
sys_stat-hsys/stat.h
sys_stat-hmkdir
sys_time-hsys/time.h
sys_times-hsys/times.h
sys_types-hsys/types.h
sys_uio-hsys/uio.h
sys_un-hsys/un.h
sys_utsname-hsys/utsname.h
sys_wait-hsys/wait.h
sysexits-hsysexits.h
system-posixstdlib.h
system-posixsystem
szprintfModernized printf
szprintf-gnuModernized printf
szprintf-posixModernized printf
T
tantan
tanftanf
tanhtanh
tanhftanhf
tanltanl
tcgetsidtcgetsid
termios-htermios.h
thrdthrd_create
thrdthrd_current
thrdthrd_detach
thrdthrd_equal
thrdthrd_exit
thrdthrd_join
thrdthrd_sleep
thrdthrd_yield
thrdISO C multithreading
threadGnulib multithreading
thread-optimMultithreading Optimizations
threadsISO C multithreading
threads-hthreads.h
timetime
time_rgmtime_r
time_rlocaltime_r
time_rzlocaltime
time_rzlocaltime_r
time-htime.h
timegmtimegm
timer-timetimer_create
timer-timetimer_delete
timer-timetimer_gettime
timer-timetimer_settime
timestimes
timespec_getclock_gettime
timespec_gettimespec_get
timespec_getgettimeofday
timespec_getrestimespec_getres
timevarProfiling of program phases
tlsGnulib multithreading
tmpfiletmpfile
tmpfile-saferClosed standard fds
tolower_ltolower_l
totalordertotalorder
totalorderftotalorderf
totalorderltotalorderl
totalordermagtotalordermag
totalordermagftotalordermagf
totalordermagltotalordermagl
toupper_ltoupper_l
towctranstowctrans
towctransComparison of character APIs
trunctrunc
trunc-ieeetrunc
truncatetruncate
truncftruncf
truncf-ieeetruncf
truncltruncl
truncl-ieeetruncl
tsearchtdelete
tsearchtfind
tsearchtsearch
tsearchtwalk
tsstss_create
tsstss_delete
tsstss_get
tsstss_set
tssISO C multithreading
ttyname_rttyname_r
tznametzname
tzsettzset
U
uchar-huchar.h
uchar-h-c23uchar.h
uchar-h-c23mbrtoc32
uchar-h-c23The char32_t type
unameuname
unicase/empty-prefix-context<unicase.h> modules
unicase/empty-suffix-context<unicase.h> modules
unicase/locale-language<unicase.h> modules
unicase/tolowertolower
unicase/tolower<unicase.h> modules
unicase/totitle<unicase.h> modules
unicase/touppertoupper
unicase/toupper<unicase.h> modules
unicase/u16-casecmp<unicase.h> modules
unicase/u16-casecoll<unicase.h> modules
unicase/u16-casefold<unicase.h> modules
unicase/u16-casexfrm<unicase.h> modules
unicase/u16-ct-casefold<unicase.h> modules
unicase/u16-ct-tolower<unicase.h> modules
unicase/u16-ct-totitle<unicase.h> modules
unicase/u16-ct-toupper<unicase.h> modules
unicase/u16-is-cased<unicase.h> modules
unicase/u16-is-casefolded<unicase.h> modules
unicase/u16-is-lowercase<unicase.h> modules
unicase/u16-is-titlecase<unicase.h> modules
unicase/u16-is-uppercase<unicase.h> modules
unicase/u16-prefix-context<unicase.h> modules
unicase/u16-suffix-context<unicase.h> modules
unicase/u16-tolower<unicase.h> modules
unicase/u16-totitle<unicase.h> modules
unicase/u16-toupper<unicase.h> modules
unicase/u32-casecmpComparison of string APIs
unicase/u32-casecmp<unicase.h> modules
unicase/u32-casecoll<unicase.h> modules
unicase/u32-casefold<unicase.h> modules
unicase/u32-casexfrm<unicase.h> modules
unicase/u32-ct-casefold<unicase.h> modules
unicase/u32-ct-tolower<unicase.h> modules
unicase/u32-ct-totitle<unicase.h> modules
unicase/u32-ct-toupper<unicase.h> modules
unicase/u32-is-cased<unicase.h> modules
unicase/u32-is-casefolded<unicase.h> modules
unicase/u32-is-lowercase<unicase.h> modules
unicase/u32-is-titlecase<unicase.h> modules
unicase/u32-is-uppercase<unicase.h> modules
unicase/u32-prefix-context<unicase.h> modules
unicase/u32-suffix-context<unicase.h> modules
unicase/u32-tolower<unicase.h> modules
unicase/u32-totitle<unicase.h> modules
unicase/u32-toupper<unicase.h> modules
unicase/u8-casecmp<unicase.h> modules
unicase/u8-casecoll<unicase.h> modules
unicase/u8-casefold<unicase.h> modules
unicase/u8-casexfrm<unicase.h> modules
unicase/u8-ct-casefold<unicase.h> modules
unicase/u8-ct-tolower<unicase.h> modules
unicase/u8-ct-totitle<unicase.h> modules
unicase/u8-ct-toupper<unicase.h> modules
unicase/u8-is-cased<unicase.h> modules
unicase/u8-is-casefolded<unicase.h> modules
unicase/u8-is-lowercase<unicase.h> modules
unicase/u8-is-titlecase<unicase.h> modules
unicase/u8-is-uppercase<unicase.h> modules
unicase/u8-prefix-context<unicase.h> modules
unicase/u8-suffix-context<unicase.h> modules
unicase/u8-tolower<unicase.h> modules
unicase/u8-totitle<unicase.h> modules
unicase/u8-toupper<unicase.h> modules
unicase/ulc-casecmp<unicase.h> modules
unicase/ulc-casecoll<unicase.h> modules
unicase/ulc-casexfrm<unicase.h> modules
uniconv/u16-conv-from-enc<uniconv.h> modules
uniconv/u16-conv-to-enc<uniconv.h> modules
uniconv/u16-strconv-from-enc<uniconv.h> modules
uniconv/u16-strconv-from-locale<uniconv.h> modules
uniconv/u16-strconv-to-enc<uniconv.h> modules
uniconv/u16-strconv-to-locale<uniconv.h> modules
uniconv/u32-conv-from-enc<uniconv.h> modules
uniconv/u32-conv-to-enc<uniconv.h> modules
uniconv/u32-strconv-from-enc<uniconv.h> modules
uniconv/u32-strconv-from-locale<uniconv.h> modules
uniconv/u32-strconv-to-enc<uniconv.h> modules
uniconv/u32-strconv-to-locale<uniconv.h> modules
uniconv/u8-conv-from-enc<uniconv.h> modules
uniconv/u8-conv-to-enc<uniconv.h> modules
uniconv/u8-strconv-from-enc<uniconv.h> modules
uniconv/u8-strconv-from-locale<uniconv.h> modules
uniconv/u8-strconv-to-enc<uniconv.h> modules
uniconv/u8-strconv-to-locale<uniconv.h> modules
unictype/base<unictype.h> modules
unictype/bidiclass-byname<unictype.h> modules
unictype/bidiclass-byname<unictype.h> modules
unictype/bidiclass-longname<unictype.h> modules
unictype/bidiclass-name<unictype.h> modules
unictype/bidiclass-name<unictype.h> modules
unictype/bidiclass-of<unictype.h> modules
unictype/bidiclass-of<unictype.h> modules
unictype/bidiclass-test<unictype.h> modules
unictype/bidiclass-test<unictype.h> modules
unictype/block-list<unictype.h> modules
unictype/block-of<unictype.h> modules
unictype/block-test<unictype.h> modules
unictype/category-and<unictype.h> modules
unictype/category-and-not<unictype.h> modules
unictype/category-byname<unictype.h> modules
unictype/category-C<unictype.h> modules
unictype/category-Cc<unictype.h> modules
unictype/category-Cf<unictype.h> modules
unictype/category-Cn<unictype.h> modules
unictype/category-Co<unictype.h> modules
unictype/category-Cs<unictype.h> modules
unictype/category-L<unictype.h> modules
unictype/category-LC<unictype.h> modules
unictype/category-Ll<unictype.h> modules
unictype/category-Lm<unictype.h> modules
unictype/category-Lo<unictype.h> modules
unictype/category-longname<unictype.h> modules
unictype/category-Lt<unictype.h> modules
unictype/category-Lu<unictype.h> modules
unictype/category-M<unictype.h> modules
unictype/category-Mc<unictype.h> modules
unictype/category-Me<unictype.h> modules
unictype/category-Mn<unictype.h> modules
unictype/category-N<unictype.h> modules
unictype/category-name<unictype.h> modules
unictype/category-Nd<unictype.h> modules
unictype/category-Nl<unictype.h> modules
unictype/category-No<unictype.h> modules
unictype/category-of<unictype.h> modules
unictype/category-or<unictype.h> modules
unictype/category-P<unictype.h> modules
unictype/category-Pc<unictype.h> modules
unictype/category-Pd<unictype.h> modules
unictype/category-Pe<unictype.h> modules
unictype/category-Pf<unictype.h> modules
unictype/category-Pi<unictype.h> modules
unictype/category-Po<unictype.h> modules
unictype/category-Ps<unictype.h> modules
unictype/category-S<unictype.h> modules
unictype/category-Sc<unictype.h> modules
unictype/category-Sk<unictype.h> modules
unictype/category-Sm<unictype.h> modules
unictype/category-So<unictype.h> modules
unictype/category-test<unictype.h> modules
unictype/category-test-withtable<unictype.h> modules
unictype/category-Z<unictype.h> modules
unictype/category-Zl<unictype.h> modules
unictype/category-Zp<unictype.h> modules
unictype/category-Zs<unictype.h> modules
unictype/combining-class<unictype.h> modules
unictype/combining-class-byname<unictype.h> modules
unictype/combining-class-longname<unictype.h> modules
unictype/combining-class-name<unictype.h> modules
unictype/ctype-alnumisalnum
unictype/ctype-alnum<unictype.h> modules
unictype/ctype-alphaisalpha
unictype/ctype-alpha<unictype.h> modules
unictype/ctype-blankisblank
unictype/ctype-blank<unictype.h> modules
unictype/ctype-cntrliscntrl
unictype/ctype-cntrl<unictype.h> modules
unictype/ctype-digitisdigit
unictype/ctype-digit<unictype.h> modules
unictype/ctype-graphisgraph
unictype/ctype-graph<unictype.h> modules
unictype/ctype-lowerislower
unictype/ctype-lower<unictype.h> modules
unictype/ctype-printisprint
unictype/ctype-print<unictype.h> modules
unictype/ctype-punctispunct
unictype/ctype-punct<unictype.h> modules
unictype/ctype-spaceisspace
unictype/ctype-space<unictype.h> modules
unictype/ctype-upperisupper
unictype/ctype-upper<unictype.h> modules
unictype/ctype-xdigitisxdigit
unictype/ctype-xdigit<unictype.h> modules
unictype/decimal-digit<unictype.h> modules
unictype/digit<unictype.h> modules
unictype/incb-byname<unictype.h> modules
unictype/incb-name<unictype.h> modules
unictype/incb-of<unictype.h> modules
unictype/joininggroup-byname<unictype.h> modules
unictype/joininggroup-name<unictype.h> modules
unictype/joininggroup-of<unictype.h> modules
unictype/joiningtype-byname<unictype.h> modules
unictype/joiningtype-longname<unictype.h> modules
unictype/joiningtype-name<unictype.h> modules
unictype/joiningtype-of<unictype.h> modules
unictype/mirror<unictype.h> modules
unictype/numeric<unictype.h> modules
unictype/property-alphabetic<unictype.h> modules
unictype/property-ascii-hex-digit<unictype.h> modules
unictype/property-bidi-arabic-digit<unictype.h> modules
unictype/property-bidi-arabic-right-to-left<unictype.h> modules
unictype/property-bidi-block-separator<unictype.h> modules
unictype/property-bidi-boundary-neutral<unictype.h> modules
unictype/property-bidi-common-separator<unictype.h> modules
unictype/property-bidi-control<unictype.h> modules
unictype/property-bidi-embedding-or-override<unictype.h> modules
unictype/property-bidi-eur-num-separator<unictype.h> modules
unictype/property-bidi-eur-num-terminator<unictype.h> modules
unictype/property-bidi-european-digit<unictype.h> modules
unictype/property-bidi-hebrew-right-to-left<unictype.h> modules
unictype/property-bidi-left-to-right<unictype.h> modules
unictype/property-bidi-non-spacing-mark<unictype.h> modules
unictype/property-bidi-other-neutral<unictype.h> modules
unictype/property-bidi-pdf<unictype.h> modules
unictype/property-bidi-segment-separator<unictype.h> modules
unictype/property-bidi-whitespace<unictype.h> modules
unictype/property-byname<unictype.h> modules
unictype/property-case-ignorable<unictype.h> modules
unictype/property-cased<unictype.h> modules
unictype/property-changes-when-casefolded<unictype.h> modules
unictype/property-changes-when-casemapped<unictype.h> modules
unictype/property-changes-when-lowercased<unictype.h> modules
unictype/property-changes-when-titlecased<unictype.h> modules
unictype/property-changes-when-uppercased<unictype.h> modules
unictype/property-combining<unictype.h> modules
unictype/property-composite<unictype.h> modules
unictype/property-currency-symbol<unictype.h> modules
unictype/property-dash<unictype.h> modules
unictype/property-decimal-digit<unictype.h> modules
unictype/property-default-ignorable-code-point<unictype.h> modules
unictype/property-deprecated<unictype.h> modules
unictype/property-diacritic<unictype.h> modules
unictype/property-emoji<unictype.h> modules
unictype/property-emoji-component<unictype.h> modules
unictype/property-emoji-modifier<unictype.h> modules
unictype/property-emoji-modifier-base<unictype.h> modules
unictype/property-emoji-presentation<unictype.h> modules
unictype/property-extended-pictographic<unictype.h> modules
unictype/property-extender<unictype.h> modules
unictype/property-format-control<unictype.h> modules
unictype/property-grapheme-base<unictype.h> modules
unictype/property-grapheme-extend<unictype.h> modules
unictype/property-grapheme-link<unictype.h> modules
unictype/property-hex-digit<unictype.h> modules
unictype/property-hyphen<unictype.h> modules
unictype/property-id-compat-math-continue<unictype.h> modules
unictype/property-id-compat-math-start<unictype.h> modules
unictype/property-id-continue<unictype.h> modules
unictype/property-id-start<unictype.h> modules
unictype/property-ideographic<unictype.h> modules
unictype/property-ids-binary-operator<unictype.h> modules
unictype/property-ids-trinary-operator<unictype.h> modules
unictype/property-ids-unary-operator<unictype.h> modules
unictype/property-ignorable-control<unictype.h> modules
unictype/property-iso-control<unictype.h> modules
unictype/property-join-control<unictype.h> modules
unictype/property-left-of-pair<unictype.h> modules
unictype/property-line-separator<unictype.h> modules
unictype/property-logical-order-exception<unictype.h> modules
unictype/property-lowercase<unictype.h> modules
unictype/property-math<unictype.h> modules
unictype/property-modifier-combining-mark<unictype.h> modules
unictype/property-non-break<unictype.h> modules
unictype/property-not-a-character<unictype.h> modules
unictype/property-numeric<unictype.h> modules
unictype/property-other-alphabetic<unictype.h> modules
unictype/property-other-default-ignorable-code-point<unictype.h> modules
unictype/property-other-grapheme-extend<unictype.h> modules
unictype/property-other-id-continue<unictype.h> modules
unictype/property-other-id-start<unictype.h> modules
unictype/property-other-lowercase<unictype.h> modules
unictype/property-other-math<unictype.h> modules
unictype/property-other-uppercase<unictype.h> modules
unictype/property-paired-punctuation<unictype.h> modules
unictype/property-paragraph-separator<unictype.h> modules
unictype/property-pattern-syntax<unictype.h> modules
unictype/property-pattern-white-space<unictype.h> modules
unictype/property-prepended-concatenation-mark<unictype.h> modules
unictype/property-private-use<unictype.h> modules
unictype/property-punctuation<unictype.h> modules
unictype/property-quotation-mark<unictype.h> modules
unictype/property-radical<unictype.h> modules
unictype/property-regional-indicator<unictype.h> modules
unictype/property-sentence-terminal<unictype.h> modules
unictype/property-soft-dotted<unictype.h> modules
unictype/property-space<unictype.h> modules
unictype/property-terminal-punctuation<unictype.h> modules
unictype/property-test<unictype.h> modules
unictype/property-titlecase<unictype.h> modules
unictype/property-unassigned-code-value<unictype.h> modules
unictype/property-unified-ideograph<unictype.h> modules
unictype/property-uppercase<unictype.h> modules
unictype/property-variation-selector<unictype.h> modules
unictype/property-white-space<unictype.h> modules
unictype/property-xid-continue<unictype.h> modules
unictype/property-xid-start<unictype.h> modules
unictype/property-zero-width<unictype.h> modules
unictype/scripts<unictype.h> modules
unictype/scripts<unictype.h> modules
unictype/scripts<unictype.h> modules
unictype/scripts<unictype.h> modules
unictype/syntax-c-ident<unictype.h> modules
unictype/syntax-c-whitespace<unictype.h> modules
unictype/syntax-java-ident<unictype.h> modules
unictype/syntax-java-whitespace<unictype.h> modules
unigbrk/u16-grapheme-breaks<unigbrk.h> modules
unigbrk/u16-grapheme-next<unigbrk.h> modules
unigbrk/u16-grapheme-prev<unigbrk.h> modules
unigbrk/u32-grapheme-breaks<unigbrk.h> modules
unigbrk/u32-grapheme-next<unigbrk.h> modules
unigbrk/u32-grapheme-prev<unigbrk.h> modules
unigbrk/u8-grapheme-breaks<unigbrk.h> modules
unigbrk/u8-grapheme-next<unigbrk.h> modules
unigbrk/u8-grapheme-prev<unigbrk.h> modules
unigbrk/uc-gbrk-prop<unigbrk.h> modules
unigbrk/uc-grapheme-breaks<unigbrk.h> modules
unigbrk/uc-is-grapheme-break<unigbrk.h> modules
unigbrk/ulc-grapheme-breaks<unigbrk.h> modules
unilbrk/u16-possible-linebreaks<unilbrk.h> modules
unilbrk/u16-width-linebreaks<unilbrk.h> modules
unilbrk/u32-possible-linebreaks<unilbrk.h> modules
unilbrk/u32-width-linebreaks<unilbrk.h> modules
unilbrk/u8-possible-linebreaks<unilbrk.h> modules
unilbrk/u8-width-linebreaks<unilbrk.h> modules
unilbrk/ulc-possible-linebreaks<unilbrk.h> modules
unilbrk/ulc-width-linebreaks<unilbrk.h> modules
uniname/uniname<uniname.h> modules
uninorm/base<uninorm.h> modules
uninorm/base<uninorm.h> modules
uninorm/canonical-decomposition<uninorm.h> modules
uninorm/composition<uninorm.h> modules
uninorm/decomposing-form<uninorm.h> modules
uninorm/decomposition<uninorm.h> modules
uninorm/filter<uninorm.h> modules
uninorm/nfc<uninorm.h> modules
uninorm/nfd<uninorm.h> modules
uninorm/nfkc<uninorm.h> modules
uninorm/nfkd<uninorm.h> modules
uninorm/u16-normalize<uninorm.h> modules
uninorm/u16-normcmp<uninorm.h> modules
uninorm/u16-normcoll<uninorm.h> modules
uninorm/u16-normxfrm<uninorm.h> modules
uninorm/u32-normalize<uninorm.h> modules
uninorm/u32-normcmp<uninorm.h> modules
uninorm/u32-normcoll<uninorm.h> modules
uninorm/u32-normxfrm<uninorm.h> modules
uninorm/u8-normalize<uninorm.h> modules
uninorm/u8-normcmp<uninorm.h> modules
uninorm/u8-normcoll<uninorm.h> modules
uninorm/u8-normxfrm<uninorm.h> modules
unistd-hunistd.h
unistd-h_exit
unistd-saferClosed standard fds
unistdio/u16-asnprintf<unistdio.h> modules
unistdio/u16-asprintf<unistdio.h> modules
unistdio/u16-snprintf<unistdio.h> modules
unistdio/u16-sprintf<unistdio.h> modules
unistdio/u16-u16-asnprintf<unistdio.h> modules
unistdio/u16-u16-asprintf<unistdio.h> modules
unistdio/u16-u16-snprintf<unistdio.h> modules
unistdio/u16-u16-sprintf<unistdio.h> modules
unistdio/u16-u16-vasnprintf<unistdio.h> modules
unistdio/u16-u16-vasprintf<unistdio.h> modules
unistdio/u16-u16-vsnprintf<unistdio.h> modules
unistdio/u16-u16-vsprintf<unistdio.h> modules
unistdio/u16-vasnprintf<unistdio.h> modules
unistdio/u16-vasprintf<unistdio.h> modules
unistdio/u16-vsnprintf<unistdio.h> modules
unistdio/u16-vsprintf<unistdio.h> modules
unistdio/u32-asnprintf<unistdio.h> modules
unistdio/u32-asprintf<unistdio.h> modules
unistdio/u32-snprintf<unistdio.h> modules
unistdio/u32-sprintf<unistdio.h> modules
unistdio/u32-u32-asnprintf<unistdio.h> modules
unistdio/u32-u32-asprintf<unistdio.h> modules
unistdio/u32-u32-snprintf<unistdio.h> modules
unistdio/u32-u32-sprintf<unistdio.h> modules
unistdio/u32-u32-vasnprintf<unistdio.h> modules
unistdio/u32-u32-vasprintf<unistdio.h> modules
unistdio/u32-u32-vsnprintf<unistdio.h> modules
unistdio/u32-u32-vsprintf<unistdio.h> modules
unistdio/u32-vasnprintf<unistdio.h> modules
unistdio/u32-vasprintf<unistdio.h> modules
unistdio/u32-vsnprintf<unistdio.h> modules
unistdio/u32-vsprintf<unistdio.h> modules
unistdio/u8-asnprintf<unistdio.h> modules
unistdio/u8-asprintf<unistdio.h> modules
unistdio/u8-snprintf<unistdio.h> modules
unistdio/u8-sprintf<unistdio.h> modules
unistdio/u8-u8-asnprintf<unistdio.h> modules
unistdio/u8-u8-asprintf<unistdio.h> modules
unistdio/u8-u8-snprintf<unistdio.h> modules
unistdio/u8-u8-sprintf<unistdio.h> modules
unistdio/u8-u8-vasnprintf<unistdio.h> modules
unistdio/u8-u8-vasprintf<unistdio.h> modules
unistdio/u8-u8-vsnprintf<unistdio.h> modules
unistdio/u8-u8-vsprintf<unistdio.h> modules
unistdio/u8-vasnprintf<unistdio.h> modules
unistdio/u8-vasprintf<unistdio.h> modules
unistdio/u8-vsnprintf<unistdio.h> modules
unistdio/u8-vsprintf<unistdio.h> modules
unistdio/ulc-asnprintf<unistdio.h> modules
unistdio/ulc-asprintf<unistdio.h> modules
unistdio/ulc-fprintf<unistdio.h> modules
unistdio/ulc-snprintf<unistdio.h> modules
unistdio/ulc-sprintf<unistdio.h> modules
unistdio/ulc-vasnprintf<unistdio.h> modules
unistdio/ulc-vasprintf<unistdio.h> modules
unistdio/ulc-vfprintf<unistdio.h> modules
unistdio/ulc-vsnprintf<unistdio.h> modules
unistdio/ulc-vsprintf<unistdio.h> modules
unistr/u16-check<unistr.h> modules
unistr/u16-chr<unistr.h> modules
unistr/u16-cmp<unistr.h> modules
unistr/u16-cmp2<unistr.h> modules
unistr/u16-cpy<unistr.h> modules
unistr/u16-cpy-alloc<unistr.h> modules
unistr/u16-endswith<unistr.h> modules
unistr/u16-mblen<unistr.h> modules
unistr/u16-mbsnlen<unistr.h> modules
unistr/u16-mbtouc<unistr.h> modules
unistr/u16-mbtouc-unsafe<unistr.h> modules
unistr/u16-mbtoucr<unistr.h> modules
unistr/u16-move<unistr.h> modules
unistr/u16-next<unistr.h> modules
unistr/u16-pcpy<unistr.h> modules
unistr/u16-prev<unistr.h> modules
unistr/u16-set<unistr.h> modules
unistr/u16-startswith<unistr.h> modules
unistr/u16-stpcpy<unistr.h> modules
unistr/u16-stpncpy<unistr.h> modules
unistr/u16-strcat<unistr.h> modules
unistr/u16-strchr<unistr.h> modules
unistr/u16-strcmp<unistr.h> modules
unistr/u16-strcoll<unistr.h> modules
unistr/u16-strcpy<unistr.h> modules
unistr/u16-strcspn<unistr.h> modules
unistr/u16-strdup<unistr.h> modules
unistr/u16-strlen<unistr.h> modules
unistr/u16-strmblen<unistr.h> modules
unistr/u16-strmbtouc<unistr.h> modules
unistr/u16-strncat<unistr.h> modules
unistr/u16-strncmp<unistr.h> modules
unistr/u16-strncpy<unistr.h> modules
unistr/u16-strnlen<unistr.h> modules
unistr/u16-strpbrk<unistr.h> modules
unistr/u16-strrchr<unistr.h> modules
unistr/u16-strspn<unistr.h> modules
unistr/u16-strstr<unistr.h> modules
unistr/u16-strtok<unistr.h> modules
unistr/u16-to-u32<unistr.h> modules
unistr/u16-to-u8<unistr.h> modules
unistr/u16-uctomb<unistr.h> modules
unistr/u32-check<unistr.h> modules
unistr/u32-chr<unistr.h> modules
unistr/u32-cmp<unistr.h> modules
unistr/u32-cmp2<unistr.h> modules
unistr/u32-cpy<unistr.h> modules
unistr/u32-cpy-alloc<unistr.h> modules
unistr/u32-endswithComparison of string APIs
unistr/u32-endswith<unistr.h> modules
unistr/u32-mblen<unistr.h> modules
unistr/u32-mbsnlenComparison of string APIs
unistr/u32-mbsnlen<unistr.h> modules
unistr/u32-mbtouc<unistr.h> modules
unistr/u32-mbtouc-unsafe<unistr.h> modules
unistr/u32-mbtoucr<unistr.h> modules
unistr/u32-move<unistr.h> modules
unistr/u32-next<unistr.h> modules
unistr/u32-pcpy<unistr.h> modules
unistr/u32-prev<unistr.h> modules
unistr/u32-set<unistr.h> modules
unistr/u32-startswithComparison of string APIs
unistr/u32-startswith<unistr.h> modules
unistr/u32-stpcpyComparison of string APIs
unistr/u32-stpcpy<unistr.h> modules
unistr/u32-stpncpyComparison of string APIs
unistr/u32-stpncpy<unistr.h> modules
unistr/u32-strcatComparison of string APIs
unistr/u32-strcat<unistr.h> modules
unistr/u32-strchrComparison of string APIs
unistr/u32-strchr<unistr.h> modules
unistr/u32-strcmpComparison of string APIs
unistr/u32-strcmp<unistr.h> modules
unistr/u32-strcollComparison of string APIs
unistr/u32-strcoll<unistr.h> modules
unistr/u32-strcpyComparison of string APIs
unistr/u32-strcpy<unistr.h> modules
unistr/u32-strcspnComparison of string APIs
unistr/u32-strcspn<unistr.h> modules
unistr/u32-strdupComparison of string APIs
unistr/u32-strdup<unistr.h> modules
unistr/u32-strlenComparison of string APIs
unistr/u32-strlen<unistr.h> modules
unistr/u32-strmblen<unistr.h> modules
unistr/u32-strmbtouc<unistr.h> modules
unistr/u32-strncatComparison of string APIs
unistr/u32-strncat<unistr.h> modules
unistr/u32-strncmpComparison of string APIs
unistr/u32-strncmp<unistr.h> modules
unistr/u32-strncpyComparison of string APIs
unistr/u32-strncpy<unistr.h> modules
unistr/u32-strnlenComparison of string APIs
unistr/u32-strnlen<unistr.h> modules
unistr/u32-strpbrkComparison of string APIs
unistr/u32-strpbrk<unistr.h> modules
unistr/u32-strrchrComparison of string APIs
unistr/u32-strrchr<unistr.h> modules
unistr/u32-strspnComparison of string APIs
unistr/u32-strspn<unistr.h> modules
unistr/u32-strstrComparison of string APIs
unistr/u32-strstr<unistr.h> modules
unistr/u32-strtokComparison of string APIs
unistr/u32-strtok<unistr.h> modules
unistr/u32-to-u16<unistr.h> modules
unistr/u32-to-u8<unistr.h> modules
unistr/u32-uctomb<unistr.h> modules
unistr/u8-check<unistr.h> modules
unistr/u8-chr<unistr.h> modules
unistr/u8-cmp<unistr.h> modules
unistr/u8-cmp2<unistr.h> modules
unistr/u8-cpy<unistr.h> modules
unistr/u8-cpy-alloc<unistr.h> modules
unistr/u8-endswith<unistr.h> modules
unistr/u8-mblen<unistr.h> modules
unistr/u8-mbsnlen<unistr.h> modules
unistr/u8-mbtouc<unistr.h> modules
unistr/u8-mbtouc-unsafe<unistr.h> modules
unistr/u8-mbtoucr<unistr.h> modules
unistr/u8-move<unistr.h> modules
unistr/u8-next<unistr.h> modules
unistr/u8-pcpy<unistr.h> modules
unistr/u8-prev<unistr.h> modules
unistr/u8-set<unistr.h> modules
unistr/u8-startswith<unistr.h> modules
unistr/u8-stpcpy<unistr.h> modules
unistr/u8-stpncpy<unistr.h> modules
unistr/u8-strcat<unistr.h> modules
unistr/u8-strchr<unistr.h> modules
unistr/u8-strcmp<unistr.h> modules
unistr/u8-strcoll<unistr.h> modules
unistr/u8-strcpy<unistr.h> modules
unistr/u8-strcspn<unistr.h> modules
unistr/u8-strdup<unistr.h> modules
unistr/u8-strlen<unistr.h> modules
unistr/u8-strmblen<unistr.h> modules
unistr/u8-strmbtouc<unistr.h> modules
unistr/u8-strncat<unistr.h> modules
unistr/u8-strncmp<unistr.h> modules
unistr/u8-strncpy<unistr.h> modules
unistr/u8-strnlen<unistr.h> modules
unistr/u8-strpbrk<unistr.h> modules
unistr/u8-strrchr<unistr.h> modules
unistr/u8-strspn<unistr.h> modules
unistr/u8-strstr<unistr.h> modules
unistr/u8-strtok<unistr.h> modules
unistr/u8-to-u16<unistr.h> modules
unistr/u8-to-u32<unistr.h> modules
unistr/u8-uctomb<unistr.h> modules
unitypes-h<unitypes.h> modules
uniwbrk/u16-wordbreaks<uniwbrk.h> modules
uniwbrk/u32-wordbreaks<uniwbrk.h> modules
uniwbrk/u8-wordbreaks<uniwbrk.h> modules
uniwbrk/ulc-wordbreaks<uniwbrk.h> modules
uniwbrk/wordbreak-property<uniwbrk.h> modules
uniwidth/u16-strwidth<uniwidth.h> modules
uniwidth/u16-width<uniwidth.h> modules
uniwidth/u32-strwidthComparison of string APIs
uniwidth/u32-strwidth<uniwidth.h> modules
uniwidth/u32-width<uniwidth.h> modules
uniwidth/u8-strwidth<uniwidth.h> modules
uniwidth/u8-width<uniwidth.h> modules
uniwidth/width<uniwidth.h> modules
unlinkunlink
unlinkatunlinkat
unlinkdirunlink
unlinkdirunlinkat
unlocked-ioMultithreading Optimizations
unlockptunlockpt
unsetenvunsetenv
update-copyrightmaintainer-makefile
usleepusleep
utimeutime
utime-hutime.h
utimensfutimens
utimensutimes
utimensutimes
utimensutime
utimenslutimes
utimensatutimensat
utmp-hutmp.h
V
valgrind-testsUsing valgrind automatically
vararraysPortability guidelines
vasprintfasprintf
vasprintfvasprintf
vasprintf-gnuasprintf
vasprintf-gnuvasprintf
vasprintf-posixasprintf
vasprintf-posixvasprintf
vaszprintfModernized printf
vaszprintf-gnuModernized printf
vaszprintf-posixModernized printf
vcs-to-changelogVCS To ChangeLog
vdprintfvdprintf
vdprintf-gnuvdprintf
vdprintf-posixvdprintf
vdzprintfModernized printf
vdzprintf-gnuModernized printf
vdzprintf-posixModernized printf
verifyassert.h
verifyCompile-time Assertions
version-etcPrinting --version and bug-reporting information
version-etc-fsfPrinting --version and bug-reporting information
vfprintf-gnuvfprintf
vfprintf-posixvfprintf
vfscanfvfscanf
vfzprintfModernized printf
vfzprintf-gnuModernized printf
vfzprintf-posixModernized printf
vlaC99 features avoided
vprintf-gnuvprintf
vprintf-posixvprintf
vscanfvscanf
vsnprintfvsnprintf
vsnprintf-gnuvsnprintf
vsnprintf-posixvsnprintf
vsnzprintfModernized printf
vsnzprintf-gnuModernized printf
vsnzprintf-posixModernized printf
vsprintf-gnuvsprintf
vsprintf-posixvsprintf
vszprintfModernized printf
vszprintf-gnuModernized printf
vszprintf-posixModernized printf
vzprintfModernized printf
vzprintf-gnuModernized printf
vzprintf-posixModernized printf
W
waitpidwaitpid
warningswarnings
wchar-hwchar.h
wchar-singleMultithreading Optimizations
wcpcpywcpcpy
wcpcpyComparison of string APIs
wcpncpywcpncpy
wcpncpyComparison of string APIs
wcrtombwcrtomb
wcscasecmpwcscasecmp
wcscasecmpComparison of string APIs
wcscatwcscat
wcscatComparison of string APIs
wcschrwcschr
wcschrComparison of string APIs
wcscmpwcscmp
wcscmpComparison of string APIs
wcscollwcscoll
wcscollComparison of string APIs
wcscpywcscpy
wcscpyComparison of string APIs
wcscspnwcscspn
wcscspnComparison of string APIs
wcsdupwcsdup
wcsdupComparison of string APIs
wcsftimewcsftime
wcslenwcslen
wcslenComparison of string APIs
wcsncasecmpwcsncasecmp
wcsncasecmpComparison of string APIs
wcsncatwcsncat
wcsncatComparison of string APIs
wcsncmpwcsncmp
wcsncmpComparison of string APIs
wcsncpywcsncpy
wcsncpyComparison of string APIs
wcsnlenwcsnlen
wcsnlenComparison of string APIs
wcsnrtombswcsnrtombs
wcsnrtombsComparison of string APIs
wcspbrkwcspbrk
wcspbrkComparison of string APIs
wcsrchrwcsrchr
wcsrchrComparison of string APIs
wcsrtombswcsrtombs
wcsrtombsComparison of string APIs
wcsspnwcsspn
wcsspnComparison of string APIs
wcsstrwcsstr
wcsstrComparison of string APIs
wcsstr-simplewcsstr
wcstokwcstok
wcstokComparison of string APIs
wcswidthwcswidth
wcswidthComparison of string APIs
wcsxfrmwcsxfrm
wcsxfrmComparison of string APIs
wctobwctob
wctombwctomb
wctranswctrans
wctransComparison of character APIs
wctypeisalnum
wctypeisalpha
wctypeisblank
wctypeiscntrl
wctypeisdigit
wctypeisgraph
wctypeislower
wctypeisprint
wctypeispunct
wctypeisspace
wctypeisupper
wctypeisxdigit
wctypetolower
wctypetoupper
wctypewctype
wctypeComparison of character APIs
wctype-hwctype.h
wctype-hiswalnum
wctype-hiswalpha
wctype-hiswcntrl
wctype-hiswgraph
wctype-hiswlower
wctype-hiswprint
wctype-hiswspace
wctype-hiswupper
wctype-htowlower
wctype-htowupper
wcwidthwcwidth
wcwidthComparison of character APIs
windows-stat-inodessys/stat.h
windows-stat-inodesInode numbers on Windows
windows-stat-timespecPrecise file timestamps on Windows
wmemchrwmemchr
wmemcmpwmemcmp
wmemcpywmemcpy
wmemmovewmemmove
wmempcpywmempcpy
wmemsetwmemset
writewrite
X
xalloc-dieOut of memory handling
xlistOrdinary containers
xmapOrdinary containers
xomapOrdinary containers
xosetOrdinary containers
xprintfModernized printf
xprintf-gnuModernized printf
xprintf-posixModernized printf
xsetOrdinary containers
xstdopenClosed standard fds
xstrerrorstrerror_r
xstring-descHandling strings with NUL characters
xsublistOrdinary containers
xvasprintfModernized printf
xvasprintf-gnuModernized printf
xvasprintf-posixModernized printf
Y
y0y0
y1y1
year2038time.h
year2038utmpx.h
year2038utmp.h
year2038getutmp
year2038getutmpx
year2038Avoiding the year 2038 problem
year2038-recommendedutmpx.h
year2038-recommendedutmp.h
year2038-recommendedgetutmp
year2038-recommendedgetutmpx
year2038-recommendedAvoiding the year 2038 problem
yieldGnulib multithreading
ynyn
Z
zprintfModernized printf
zprintf-gnuModernized printf
zprintf-posixModernized printf
Jump to:   _  
A   B   C   D   E   F   G   H   I   J   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y   Z  

Next: , Previous: , Up: GNU Gnulib   [Contents][Index]

Undocumented Module Index

These are the modules that are not explicitly documented in this manual. Please look at the respective module description. (Ideally, this list should be as small as possible.)

Jump to:   A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y  
A
aclUndocumented Module Index
acl-permissionsUndocumented Module Index
alignofUndocumented Module Index
allocatorUndocumented Module Index
amemxfrmUndocumented Module Index
ansi-c++-optUndocumented Module Index
areadlinkatUndocumented Module Index
areadlinkat-with-sizeUndocumented Module Index
argv-iterUndocumented Module Index
array-mergesortUndocumented Module Index
assureUndocumented Module Index
astrxfrmUndocumented Module Index
asyncsafe-spinUndocumented Module Index
at-initUndocumented Module Index
autobuildUndocumented Module Index
B
backup-renameUndocumented Module Index
backupfileUndocumented Module Index
base32Undocumented Module Index
base64Undocumented Module Index
bcp47Undocumented Module Index
binary-ioUndocumented Module Index
bisonUndocumented Module Index
bison-i18nUndocumented Module Index
bitsetvUndocumented Module Index
boot-timeUndocumented Module Index
builtin-expectUndocumented Module Index
C
c-dtoastrUndocumented Module Index
c-file-typeUndocumented Module Index
c-ldtoastrUndocumented Module Index
c-nstrftimeUndocumented Module Index
c-snprintfUndocumented Module Index
c-stackUndocumented Module Index
c-strcaseUndocumented Module Index
c-strtofUndocumented Module Index
c-vasnprintfUndocumented Module Index
c-vasprintfUndocumented Module Index
c-vsnprintfUndocumented Module Index
c99Undocumented Module Index
canon-hostUndocumented Module Index
canonicalizeUndocumented Module Index
careadlinkatUndocumented Module Index
chdir-longUndocumented Module Index
chmodatUndocumented Module Index
chownatUndocumented Module Index
classpathUndocumented Module Index
clean-temp-simpleUndocumented Module Index
clock-timeUndocumented Module Index
cloexecUndocumented Module Index
close-streamUndocumented Module Index
closeinUndocumented Module Index
closeoutUndocumented Module Index
concat-filenameUndocumented Module Index
config-hUndocumented Module Index
copy-fileUndocumented Module Index
cpu-supportsUndocumented Module Index
crcUndocumented Module Index
crc-x86_64Undocumented Module Index
crypto/arcfourUndocumented Module Index
crypto/arctwoUndocumented Module Index
crypto/desUndocumented Module Index
crypto/gcUndocumented Module Index
crypto/gc-arcfourUndocumented Module Index
crypto/gc-arctwoUndocumented Module Index
crypto/gc-camelliaUndocumented Module Index
crypto/gc-desUndocumented Module Index
crypto/gc-hmac-md5Undocumented Module Index
crypto/gc-hmac-sha1Undocumented Module Index
crypto/gc-hmac-sha256Undocumented Module Index
crypto/gc-hmac-sha512Undocumented Module Index
crypto/gc-md2Undocumented Module Index
crypto/gc-md4Undocumented Module Index
crypto/gc-md5Undocumented Module Index
crypto/gc-pbkdf2Undocumented Module Index
crypto/gc-rijndaelUndocumented Module Index
crypto/gc-sha1Undocumented Module Index
crypto/gc-sha256Undocumented Module Index
crypto/gc-sha512Undocumented Module Index
crypto/gc-sm3Undocumented Module Index
crypto/hmac-md5Undocumented Module Index
crypto/hmac-sha1Undocumented Module Index
crypto/hmac-sha256Undocumented Module Index
crypto/hmac-sha512Undocumented Module Index
crypto/md2Undocumented Module Index
crypto/md2-bufferUndocumented Module Index
crypto/md4Undocumented Module Index
crypto/md4-bufferUndocumented Module Index
crypto/md5Undocumented Module Index
crypto/md5-bufferUndocumented Module Index
crypto/rijndaelUndocumented Module Index
crypto/sha1Undocumented Module Index
crypto/sha1-bufferUndocumented Module Index
crypto/sha256Undocumented Module Index
crypto/sha256-bufferUndocumented Module Index
crypto/sha3Undocumented Module Index
crypto/sha3-bufferUndocumented Module Index
crypto/sha512Undocumented Module Index
crypto/sha512-bufferUndocumented Module Index
crypto/sm3Undocumented Module Index
crypto/sm3-bufferUndocumented Module Index
csharpcompUndocumented Module Index
csharpcomp-scriptUndocumented Module Index
csharpexecUndocumented Module Index
csharpexec-scriptUndocumented Module Index
cycle-checkUndocumented Module Index
cygpathUndocumented Module Index
D
d-inoUndocumented Module Index
d-typeUndocumented Module Index
dcomp-scriptUndocumented Module Index
dev-inoUndocumented Module Index
dfaUndocumented Module Index
di-setUndocumented Module Index
diffseqUndocumented Module Index
dirname-lgplUndocumented Module Index
double-slash-rootUndocumented Module Index
dtoastrUndocumented Module Index
dtotimespecUndocumented Module Index
E
eloop-thresholdUndocumented Module Index
errno-iterUndocumented Module Index
excludeUndocumented Module Index
executeUndocumented Module Index
exitfailUndocumented Module Index
F
fatal-signalUndocumented Module Index
fd-safer-flagUndocumented Module Index
fdlUndocumented Module Index
fdl-1.3Undocumented Module Index
file-has-aclUndocumented Module Index
file-remoteUndocumented Module Index
file-setUndocumented Module Index
file-typeUndocumented Module Index
fileblocksUndocumented Module Index
filemodeUndocumented Module Index
filenameUndocumented Module Index
filenamecatUndocumented Module Index
filenamecat-lgplUndocumented Module Index
filesystem-remoteUndocumented Module Index
filevercmpUndocumented Module Index
findprogUndocumented Module Index
findprog-inUndocumented Module Index
findprog-lgplUndocumented Module Index
fpe-trappingUndocumented Module Index
fpieeeUndocumented Module Index
fprintftimeUndocumented Module Index
fpucwUndocumented Module Index
frexp-nolibmUndocumented Module Index
frexpl-nolibmUndocumented Module Index
fstrcmpUndocumented Module Index
ftoastrUndocumented Module Index
full-readUndocumented Module Index
full-writeUndocumented Module Index
fwriteerrorUndocumented Module Index
G
gendocsUndocumented Module Index
get_ppid_ofUndocumented Module Index
get_progname_ofUndocumented Module Index
get-rusage-asUndocumented Module Index
get-rusage-dataUndocumented Module Index
gethrxtimeUndocumented Module Index
getlocalename_l-unsafeUndocumented Module Index
getlocalename_l-unsafe-limitedUndocumented Module Index
getndelim2Undocumented Module Index
getnlineUndocumented Module Index
gnu-makeUndocumented Module Index
gnu-web-doc-updateUndocumented Module Index
gnulib-i18nUndocumented Module Index
gocomp-scriptUndocumented Module Index
gperfUndocumented Module Index
H
hard-localeUndocumented Module Index
hashUndocumented Module Index
hashcode-file-inodeUndocumented Module Index
hashcode-memUndocumented Module Index
hashcode-named-fileUndocumented Module Index
hashcode-string1Undocumented Module Index
hashcode-string2Undocumented Module Index
hashkey-stringUndocumented Module Index
host-cpu-c-abiUndocumented Module Index
host-osUndocumented Module Index
hostentUndocumented Module Index
humanUndocumented Module Index
I
i-ringUndocumented Module Index
iallocUndocumented Module Index
iconv-hUndocumented Module Index
idcacheUndocumented Module Index
idpriv-dropUndocumented Module Index
idpriv-droptempUndocumented Module Index
idxUndocumented Module Index
ignore-valueUndocumented Module Index
immutableUndocumented Module Index
include_nextUndocumented Module Index
ino-mapUndocumented Module Index
integer_lengthUndocumented Module Index
integer_length_lUndocumented Module Index
integer_length_llUndocumented Module Index
inttostrUndocumented Module Index
inttypes-h-incompleteUndocumented Module Index
isapipeUndocumented Module Index
isdirUndocumented Module Index
isfinite-no-c++Undocumented Module Index
isinf-no-c++Undocumented Module Index
isnan-no-c++Undocumented Module Index
isnandUndocumented Module Index
isnand-nolibmUndocumented Module Index
isnanf-nolibmUndocumented Module Index
isnanl-nolibmUndocumented Module Index
issymlinkUndocumented Module Index
issymlinkatUndocumented Module Index
J
javacompUndocumented Module Index
javacomp-scriptUndocumented Module Index
javaexecUndocumented Module Index
javaexec-scriptUndocumented Module Index
javaversionUndocumented Module Index
jit/cacheUndocumented Module Index
K
kwsetUndocumented Module Index
L
lddUndocumented Module Index
ldtoastrUndocumented Module Index
lib-ignoreUndocumented Module Index
libgmpUndocumented Module Index
libgmp-mpqUndocumented Module Index
libgmp-mpzUndocumented Module Index
libsigsegvUndocumented Module Index
libtextstyleUndocumented Module Index
libtextstyle-optionalUndocumented Module Index
linebufferUndocumented Module Index
link-followUndocumented Module Index
localeinfoUndocumented Module Index
localenameUndocumented Module Index
localename-environUndocumented Module Index
long-optionsUndocumented Module Index
longlongUndocumented Module Index
M
mallocaUndocumented Module Index
mathlUndocumented Module Index
mbiter-auxUndocumented Module Index
mbmemcasecmpUndocumented Module Index
mbmemcasecollUndocumented Module Index
mbszeroUndocumented Module Index
mem-hash-mapUndocumented Module Index
memcasecmpUndocumented Module Index
memchr2Undocumented Module Index
memcmp2Undocumented Module Index
memcollUndocumented Module Index
memeqUndocumented Module Index
memxorUndocumented Module Index
minmaxUndocumented Module Index
mkancesdirsUndocumented Module Index
mkdir-pUndocumented Module Index
mktempdUndocumented Module Index
modechangeUndocumented Module Index
modula2comp-scriptUndocumented Module Index
mpsortUndocumented Module Index
msvc-invalUndocumented Module Index
msvc-nothrowUndocumented Module Index
multiarchUndocumented Module Index
N
nanUndocumented Module Index
next-primeUndocumented Module Index
nlcanonUndocumented Module Index
no-c++Undocumented Module Index
nocrashUndocumented Module Index
nstrftime-limitedUndocumented Module Index
O
openat-hUndocumented Module Index
opendiratUndocumented Module Index
openmp-initUndocumented Module Index
P
parse-datetime2Undocumented Module Index
parse-durationUndocumented Module Index
passfdUndocumented Module Index
perlUndocumented Module Index
physmemUndocumented Module Index
pipe-filter-giUndocumented Module Index
pipe-filter-iiUndocumented Module Index
pmccabe2htmlUndocumented Module Index
posix-shellUndocumented Module Index
posixtmUndocumented Module Index
posixverUndocumented Module Index
printf-frexpUndocumented Module Index
printf-frexplUndocumented Module Index
printf-safeUndocumented Module Index
priv-setUndocumented Module Index
propernameUndocumented Module Index
propername-liteUndocumented Module Index
pt_chownUndocumented Module Index
Q
qaclUndocumented Module Index
qcopy-aclUndocumented Module Index
qset-aclUndocumented Module Index
quotearg-simpleUndocumented Module Index
R
read-fileUndocumented Module Index
readtokensUndocumented Module Index
readtokens0Undocumented Module Index
regex-quoteUndocumented Module Index
regexprops-genericUndocumented Module Index
relocatable-prog-wrapperUndocumented Module Index
rmdir-errnoUndocumented Module Index
root-uidUndocumented Module Index
S
sameUndocumented Module Index
save-cwdUndocumented Module Index
savedirUndocumented Module Index
savewdUndocumented Module Index
selinux-atUndocumented Module Index
setlocale-fixesUndocumented Module Index
settimeUndocumented Module Index
sfl-istreamUndocumented Module Index
sh-filenameUndocumented Module Index
sh-quoteUndocumented Module Index
sigdelayUndocumented Module Index
signbit-no-c++Undocumented Module Index
signed-nanUndocumented Module Index
signed-snanUndocumented Module Index
sigpipe-dieUndocumented Module Index
sigsegvUndocumented Module Index
simple-atomicUndocumented Module Index
size_maxUndocumented Module Index
snanUndocumented Module Index
socketsUndocumented Module Index
socklenUndocumented Module Index
sparcv8+Undocumented Module Index
spawn-pipeUndocumented Module Index
ssfmallocUndocumented Module Index
ssize_tUndocumented Module Index
stackUndocumented Module Index
stat-macrosUndocumented Module Index
statatUndocumented Module Index
std-gnu11Undocumented Module Index
std-gnu23Undocumented Module Index
stdbit-hUndocumented Module Index
stdio-windowsUndocumented Module Index
stdopenUndocumented Module Index
strcaseUndocumented Module Index
streqUndocumented Module Index
streq-optUndocumented Module Index
striconvehaUndocumented Module Index
string-buffer-reversedUndocumented Module Index
stringeqUndocumented Module Index
strnlen1Undocumented Module Index
strnulUndocumented Module Index
supersedeUndocumented Module Index
system-quoteUndocumented Module Index
T
tempnameUndocumented Module Index
term-style-controlUndocumented Module Index
terminfoUndocumented Module Index
terminfo-hUndocumented Module Index
test-framework-shUndocumented Module Index
test-xfailUndocumented Module Index
timespecUndocumented Module Index
timespec-addUndocumented Module Index
timespec-subUndocumented Module Index
tmpdirUndocumented Module Index
trimUndocumented Module Index
U
u64Undocumented Module Index
ucs4-utf16Undocumented Module Index
ucs4-utf8Undocumented Module Index
unicodeioUndocumented Module Index
unictype/bidiclass-allUndocumented Module Index
unictype/block-allUndocumented Module Index
unictype/category-allUndocumented Module Index
unictype/combining-class-allUndocumented Module Index
unictype/incb-allUndocumented Module Index
unictype/joininggroup-allUndocumented Module Index
unictype/joiningtype-allUndocumented Module Index
unictype/property-allUndocumented Module Index
unictype/scripts-allUndocumented Module Index
unlink-busyUndocumented Module Index
useless-if-before-freeUndocumented Module Index
userspecUndocumented Module Index
utf16-ucs4Undocumented Module Index
utf16-ucs4-unsafeUndocumented Module Index
utf8-ucs4Undocumented Module Index
utf8-ucs4-unsafeUndocumented Module Index
utimecmpUndocumented Module Index
V
va-argsUndocumented Module Index
vaprintfUndocumented Module Index
vasnprintfUndocumented Module Index
vasnprintf-gnuUndocumented Module Index
vasnprintf-posixUndocumented Module Index
vasnwprintfUndocumented Module Index
vasnwprintf-gnuUndocumented Module Index
vasnwprintf-posixUndocumented Module Index
vc-list-filesUndocumented Module Index
vc-mtimeUndocumented Module Index
verrorUndocumented Module Index
version-stampUndocumented Module Index
vma-iterUndocumented Module Index
vma-protUndocumented Module Index
W
wait-processUndocumented Module Index
wgetcwd-lgplUndocumented Module Index
windows-cygpathUndocumented Module Index
winsz-ioctlUndocumented Module Index
winsz-termiosUndocumented Module Index
write-any-fileUndocumented Module Index
X
xalignallocUndocumented Module Index
xallocUndocumented Module Index
xalloc-oversizedUndocumented Module Index
xbinary-ioUndocumented Module Index
xconcat-filenameUndocumented Module Index
xfreopenUndocumented Module Index
xgetcwdUndocumented Module Index
xgetcwd-lgplUndocumented Module Index
xgetdomainnameUndocumented Module Index
xgetgroupsUndocumented Module Index
xgethostnameUndocumented Module Index
xhashUndocumented Module Index
xmallocaUndocumented Module Index
xmemcollUndocumented Module Index
xmemdup0Undocumented Module Index
xnanosleepUndocumented Module Index
xreadlinkUndocumented Module Index
xreadlinkatUndocumented Module Index
xsetenvUndocumented Module Index
xsizeUndocumented Module Index
xstriconvUndocumented Module Index
xstriconvehUndocumented Module Index
xstring-bufferUndocumented Module Index
xstring-buffer-reversedUndocumented Module Index
xstrndupUndocumented Module Index
xstrtodUndocumented Module Index
xstrtoimaxUndocumented Module Index
xstrtolUndocumented Module Index
xstrtol-errorUndocumented Module Index
xstrtoldUndocumented Module Index
xstrtollUndocumented Module Index
xstrtoumaxUndocumented Module Index
Y
yesnoUndocumented Module Index
Jump to:   A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y  

Previous: , Up: GNU Gnulib   [Contents][Index]

General Index

Jump to:   _   -   ?   .   (   )   [   ]   {   }   *   \   ^   +   =   |   $  
A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y  
_
__attribute__Attributes
__libc_single_threaded__libc_single_threaded
__VA_ARGS__C99 features assumed
_dl_find_object_dl_find_object
_Exit_Exit
_exit_exit
_Fork_Fork
_GL_EXTERN_INLINEextern inline
_GL_INLINEextern inline
_GL_INLINE_HEADER_BEGINextern inline
_GL_INLINE_HEADER_ENDextern inline
_longjmp_longjmp
_NoreturnNon-returning Functions
_setjmp_setjmp
_tolower_tolower
_toupper_toupper
-
‘-’List Operators
?
‘?’Match-zero-or-one Operator
.
‘.’Match-any-character Operator
.tarball-versionSetting the package version
(
(Grouping Operators
)
)Grouping Operators
[
‘[’List Operators
‘[^’List Operators
‘[=’ in regexEquivalence Class Operators
‘[colon’ in regexCharacter Class Operators
]
‘]’List Operators
{
‘{’Interval Operators
}
‘}’Interval Operators
*
‘*’Match-zero-or-more Operator
\
\The Backslash Character
‘\’List Operators
‘\'’Match-end-of-string Operator
\(Grouping Operators
\)Grouping Operators
‘\{’Interval Operators
‘\}’Interval Operators
‘\`’Match-beginning-of-string Operator
‘\<’Match-beginning-of-word Operator
‘\>’Match-end-of-word Operator
\|Alternation Operator
‘\b’Match-word-boundary Operator
‘\B’Match-within-word Operator
‘\s’Match-space Operator
‘\S’Match-non-space Operator
‘\w’Match-word-constituent Operator
‘\W’Match-non-word-constituent Operator
^
^Match-beginning-of-line Operator
‘^’List Operators
+
‘+’Match-one-or-more Operator
=
‘=]’ in regexEquivalence Class Operators
|
|Alternation Operator
$
$Match-end-of-line Operator
A
a64la64l
abortabort
Aborting executionOut of memory handling
absabs
AC_LIB_HAVE_LINKFLAGS(name, [dependencies], [includes], [testcode], [missing-message])Searching for Libraries
AC_LIB_LINKFLAGS(name, [dependencies])Searching for Libraries
acceptaccept
accept4accept4
accessaccess
acctacct
acosacos
acosfacosf
acoshacosh
acoshfacoshf
acoshlacoshl
acoslacosl
acospiacospi
acospifacospif
acospilacospil
addmntentaddmntent
addseverityaddseverity
adjtimeadjtime
adjtimexadjtimex
advanceadvance
aio_cancelaio_cancel
aio_erroraio_error
aio_fsyncaio_fsync
aio_initaio_init
aio_readaio_read
aio_returnaio_return
aio_suspendaio_suspend
aio_writeaio_write
alarmalarm
aligned_allocaligned_alloc
ALLOCSafe Allocation Macros
ALLOC_NSafe Allocation Macros
ALLOC_N_UNINITIALIZEDSafe Allocation Macros
allocaalloca
allocaalloca-opt
allocated initializationGNU Regular Expression Compiling
alphasortalphasort
alternation operatorAlternation Operator
alternation operator and ‘^’Match-beginning-of-line Operator
anchoringAnchoring Operators
anchorsMatch-beginning-of-line Operator
anchorsMatch-end-of-line Operator
arc4randomarc4random
arc4random_bufarc4random_buf
arc4random_uniformarc4random_uniform
argp_err_exit_statusargp_err_exit_status
argp_errorargp_error
argp_failureargp_failure
argp_helpargp_help
argp_parseargp_parse
argp_program_bug_addressargp_program_bug_address
argp_program_versionargp_program_version
argp_program_version_hookargp_program_version_hook
argp_state_helpargp_state_help
argp_usageargp_usage
argz_addargz_add
argz_add_separgz_add_sep
argz_appendargz_append
argz_countargz_count
argz_createargz_create
argz_create_separgz_create_sep
argz_deleteargz_delete
argz_extractargz_extract
argz_insertargz_insert
argz_nextargz_next
argz_replaceargz_replace
argz_stringifyargz_stringify
arithmetic type conversionArithmetic Type Conversion
asctimeasctime
asctime_rasctime_r
asinasin
asinfasinf
asinhasinh
asinhfasinhf
asinhlasinhl
asinlasinl
asinpiasinpi
asinpifasinpif
asinpilasinpil
asprintfasprintf
assertassert
assertionCompile-time Assertions
at_quick_exitat_quick_exit
atanatan
atan2atan2
atan2fatan2f
atan2latan2l
atan2piatan2pi
atan2pifatan2pif
atan2pilatan2pil
atanfatanf
atanhatanh
atanhfatanhf
atanhlatanhl
atanlatanl
atanpiatanpi
atanpifatanpif
atanpilatanpil
atexitatexit
atofatof
atoiatoi
atolatol
atollatoll
atomic_compare_exchange_strongatomic_compare_exchange_strong
atomic_compare_exchange_strong_explicitatomic_compare_exchange_strong_explicit
atomic_compare_exchange_weakatomic_compare_exchange_weak
atomic_compare_exchange_weak_explicitatomic_compare_exchange_weak_explicit
atomic_exchangeatomic_exchange
atomic_exchange_explicitatomic_exchange_explicit
atomic_fetch_addatomic_fetch_add
atomic_fetch_add_explicitatomic_fetch_add_explicit
atomic_fetch_andatomic_fetch_and
atomic_fetch_and_explicitatomic_fetch_and_explicit
atomic_fetch_oratomic_fetch_or
atomic_fetch_or_explicitatomic_fetch_or_explicit
atomic_fetch_subatomic_fetch_sub
atomic_fetch_sub_explicitatomic_fetch_sub_explicit
atomic_fetch_xoratomic_fetch_xor
atomic_fetch_xor_explicitatomic_fetch_xor_explicit
atomic_flag_clearatomic_flag_clear
atomic_flag_clear_explicitatomic_flag_clear_explicit
atomic_flag_test_and_setatomic_flag_test_and_set
atomic_flag_test_and_set_explicitatomic_flag_test_and_set_explicit
atomic_initatomic_init
atomic_is_lock_freeatomic_is_lock_free
atomic_loadatomic_load
atomic_load_explicitatomic_load_explicit
atomic_signal_fenceatomic_signal_fence
atomic_storeatomic_store
atomic_store_explicitatomic_store_explicit
atomic_thread_fenceatomic_thread_fence
AttributesAttributes
authdes_createauthdes_create
authdes_getucredauthdes_getucred
authdes_pk_createauthdes_pk_create
authnone_createauthnone_create
authunix_createauthunix_create
authunix_create_defaultauthunix_create_default
autopoint, caveatgettextize and autopoint
AwkPredefined Syntaxes
B
back-referencesBack-reference Operator
backtracebacktrace
backtrace_symbolsbacktrace_symbols
backtrace_symbols_fdbacktrace_symbols_fd
backtrackingMatch-zero-or-more Operator
backtrackingAlternation Operator
basenamebasename
bcmpbcmp
bcopybcopy
bdflushbdflush
be16tohbe16toh
be32tohbe32toh
be64tohbe64toh
beginning-of-line operatorMatch-beginning-of-line Operator
bindbind
bind_textdomain_codesetbind_textdomain_codeset
bindresvportbindresvport
bindtextdomainbindtextdomain
block sizestat-size
bracket expressionList Operators
brkbrk
bsd_signalbsd_signal
bsearchbsearch
bswap_16bswap_16
bswap_32bswap_32
bswap_64bswap_64
btowcbtowc
buffer field, set by re_compile_patternGNU Regular Expression Compiling
buffer initializationGNU Regular Expression Compiling
bzerobzero
C
C++ header filesHeader files
C++ tests modulesExtra tests modules
c16rtombc16rtomb
c32rtombc32rtomb
c8rtombc8rtomb
cabscabs
cabsfcabsf
cabslcabsl
cacoscacos
cacosfcacosf
cacoshcacosh
cacoshfcacoshf
cacoshlcacoshl
cacoslcacosl
call_oncecall_once
calloccalloc
callrpccallrpc
canonicalizecanonicalize
canonicalize_file_namecanonicalize_file_name
canonicalizefcanonicalizef
canonicalizelcanonicalizel
capgetcapget
capsetcapset
cargcarg
cargfcargf
carglcargl
casincasin
casinfcasinf
casinhcasinh
casinhfcasinhf
casinhlcasinhl
casinlcasinl
catancatan
catanfcatanf
catanhcatanh
catanhfcatanhf
catanhlcatanhl
catanlcatanl
catclosecatclose
catgetscatgets
catopencatopen
cbrtcbrt
cbrtfcbrtf
cbrtlcbrtl
ccosccos
ccosfccosf
ccoshccosh
ccoshfccoshf
ccoshlccoshl
ccoslccosl
ceilceil
ceilfceilf
ceillceill
cexpcexp
cexpfcexpf
cexplcexpl
cfgetispeedcfgetispeed
cfgetospeedcfgetospeed
cfmakerawcfmakeraw
cfreecfree
cfsetispeedcfsetispeed
cfsetospeedcfsetospeed
cfsetspeedcfsetspeed
changeloggitlog-to-changelog
character classesCharacter Class Operators
chdirchdir
chmodchmod
chownchown
chrootchroot
cimagcimag
cimagfcimagf
cimaglcimagl
clearenvclearenv
clearerrclearerr
clearerr_unlockedclearerr_unlocked
clnt_broadcastclnt_broadcast
clnt_createclnt_create
clnt_pcreateerrorclnt_pcreateerror
clnt_perrnoclnt_perrno
clnt_perrorclnt_perror
clnt_spcreateerrorclnt_spcreateerror
clnt_sperrnoclnt_sperrno
clnt_sperrorclnt_sperror
clntraw_createclntraw_create
clnttcp_createclnttcp_create
clntudp_bufcreateclntudp_bufcreate
clntudp_createclntudp_create
clntunix_createclntunix_create
clockclock
clock_adjtimeclock_adjtime
clock_getcpuclockidclock_getcpuclockid
clock_getresclock_getres
clock_gettimeclock_gettime
clock_nanosleepclock_nanosleep
clock_settimeclock_settime
clogclog
clog10clog10
clog10fclog10f
clog10lclog10l
clogfclogf
cloglclogl
cloneclone
closeclose
close_rangeclose_range
closedirclosedir
closefromclosefrom
closelogcloselog
CMPLXCMPLX
CMPLXFCMPLXF
CMPLXLCMPLXL
cnd_broadcastcnd_broadcast
cnd_destroycnd_destroy
cnd_initcnd_init
cnd_signalcnd_signal
cnd_timedwaitcnd_timedwait
cnd_waitcnd_wait
‘colon]’ in regexCharacter Class Operators
comments describing functionsSpecification
compoundncompoundn
compoundnfcompoundnf
compoundnlcompoundnl
conditional dependenciesConditional dependencies
configmake.h, module for updatingconfigmake
confstrconfstr
conjconj
conjfconjf
conjlconjl
connectconnect
copy_file_rangecopy_file_range
copysigncopysign
copysignfcopysignf
copysignlcopysignl
coscos
cosfcosf
coshcosh
coshfcoshf
coshlcoshl
coslcosl
cospicospi
cospifcospif
cospilcospil
cpowcpow
cpowfcpowf
cpowlcpowl
cprojcproj
cprojfcprojf
cprojlcprojl
crealcreal
crealfcrealf
creallcreall
creatcreat
cryptcrypt
csincsin
csinfcsinf
csinhcsinh
csinhfcsinhf
csinhlcsinhl
csinlcsinl
csqrtcsqrt
csqrtfcsqrtf
csqrtlcsqrtl
ctanctan
ctanfctanf
ctanhctanh
ctanhfctanhf
ctanhlctanhl
ctanlctanl
ctermidctermid
ctimectime
ctime_rctime_r
cuseridcuserid
D
daddldaddl
daemondaemon
daylightdaylight
dbm_clearerrdbm_clearerr
dbm_closedbm_close
dbm_deletedbm_delete
dbm_errordbm_error
dbm_fetchdbm_fetch
dbm_firstkeydbm_firstkey
dbm_nextkeydbm_nextkey
dbm_opendbm_open
dbm_storedbm_store
dcgettextdcgettext
dcgettext_ldcgettext_l
dcngettextdcngettext
dcngettext_ldcngettext_l
ddivlddivl
DEF filesVisual Studio Compatibility
describing functions, locatingSpecification
dfmaldfmal
dgettextdgettext
dgettext_ldgettext_l
difftimedifftime
dirfddirfd
dirnamedirname
divdiv
dl_iterate_phdrdl_iterate_phdr
dladdrdladdr
dladdr1dladdr1
dlclosedlclose
dlerrordlerror
dlinfodlinfo
dlmopendlmopen
dlopendlopen
dlsymdlsym
dlvsymdlvsym
dmulldmull
dn_compdn_comp
dn_expanddn_expand
dn_skipnamedn_skipname
dngettextdngettext
dngettext_ldngettext_l
double inclusion of header filesHeader files
dprintfdprintf
drand48drand48
drand48_rdrand48_r
dremdrem
dremfdremf
dremldreml
dsqrtldsqrtl
dsubldsubl
dupdup
dup2dup2
dup3dup3
duplocaleduplocale
dysizedysize
E
eaccesseaccess
ecvtecvt
ecvt_recvt_r
EgrepPredefined Syntaxes
EmacsPredefined Syntaxes
encryptencrypt
end in struct re_registersUsing Registers
end-of-line operatorMatch-end-of-line Operator
endaliasentendaliasent
endfsentendfsent
endgrentendgrent
endhostentendhostent
endmntentendmntent
endnetentendnetent
endnetgrentendnetgrent
endprotoentendprotoent
endpwentendpwent
endrpcentendrpcent
endserventendservent
endsgentendsgent
endspentendspent
endttyentendttyent
endusershellendusershell
endutentendutent
endutxentendutxent
environenviron
envz_addenvz_add
envz_entryenvz_entry
envz_getenvz_get
envz_mergeenvz_merge
envz_removeenvz_remove
envz_stripenvz_strip
epoll_createepoll_create
epoll_create1epoll_create1
epoll_ctlepoll_ctl
epoll_pwaitepoll_pwait
epoll_pwait2epoll_pwait2
epoll_waitepoll_wait
equivalence class expression in regexEquivalence Class Operators
erand48erand48
erand48_rerand48_r
erferf
erfcerfc
erfcferfcf
erfclerfcl
erfferff
erflerfl
errerr
errnoerrno
errorerror
errorprogname and getprogname
error_at_lineerror_at_line
error_message_counterror_message_count
error_one_per_lineerror_one_per_line
error_print_prognameerror_print_progname
errxerrx
ether_atonether_aton
ether_aton_rether_aton_r
ether_hosttonether_hostton
ether_lineether_line
ether_ntoaether_ntoa
ether_ntoa_rether_ntoa_r
ether_ntohostether_ntohost
euidaccesseuidaccess
eventfdeventfd
eventfd_readeventfd_read
eventfd_writeeventfd_write
execlexecl
execleexecle
execlpexeclp
execvexecv
execveexecve
execveatexecveat
execvpexecvp
execvpeexecvpe
exitexit
expexp
exp10exp10
exp10fexp10f
exp10lexp10l
exp10m1exp10m1
exp10m1fexp10m1f
exp10m1lexp10m1l
exp2exp2
exp2fexp2f
exp2lexp2l
exp2m1exp2m1
exp2m1fexp2m1f
exp2m1lexp2m1l
expfexpf
explexpl
explicit_bzeroexplicit_bzero
expm1expm1
expm1fexpm1f
expm1lexpm1l
EXPR_SIGNEDArithmetic Type Properties
extern inlineextern inline
Extra tests modulesExtra tests modules
F
fabsfabs
fabsffabsf
fabslfabsl
faccessatfaccessat
faddfadd
faddlfaddl
fallocatefallocate
fanotify_initfanotify_init
fanotify_markfanotify_mark
fastmap initializationGNU Regular Expression Compiling
fastmapsSearching with Fastmaps
fattachfattach
fchdirfchdir
fchmodfchmod
fchmodatfchmodat
fchownfchown
fchownatfchownat
fclosefclose
fcloseallfcloseall
fcntlfcntl
fcvtfcvt
fcvt_rfcvt_r
FD_CLRFD_CLR
FD_ISSETFD_ISSET
FD_SETFD_SET
FD_ZEROFD_ZERO
fdatasyncfdatasync
fdetachfdetach
fdimfdim
fdimffdimf
fdimlfdiml
fdivfdiv
fdivlfdivl
fdopenfdopen
fdopendirfdopendir
feclearexceptfeclearexcept
fedisableexceptfedisableexcept
feenableexceptfeenableexcept
fegetenvfegetenv
fegetexceptfegetexcept
fegetexceptflagfegetexceptflag
fegetmodefegetmode
fegetroundfegetround
feholdexceptfeholdexcept
feoffeof
feof_unlockedfeof_unlocked
feraiseexceptferaiseexcept
ferrorferror
ferror_unlockedferror_unlocked
fesetenvfesetenv
fesetexceptfesetexcept
fesetexceptflagfesetexceptflag
fesetmodefesetmode
fesetroundfesetround
fetestexceptfetestexcept
fetestexceptflagfetestexceptflag
feupdateenvfeupdateenv
fexecvefexecve
fflushfflush
fflush_unlockedfflush_unlocked
ffmaffma
ffmalffmal
ffsffs
ffslffsl
ffsllffsll
fgetcfgetc
fgetc_unlockedfgetc_unlocked
fgetfileconfgetfilecon
fgetgrentfgetgrent
fgetgrent_rfgetgrent_r
fgetposfgetpos
fgetpwentfgetpwent
fgetpwent_rfgetpwent_r
fgetsfgets
fgets_unlockedfgets_unlocked
fgetsgentfgetsgent
fgetsgent_rfgetsgent_r
fgetspentfgetspent
fgetspent_rfgetspent_r
fgetwcfgetwc
fgetwc_unlockedfgetwc_unlocked
fgetwsfgetws
fgetws_unlockedfgetws_unlocked
fgetxattrfgetxattr
filenofileno
fileno_unlockedfileno_unlocked
Finding modulesWhich modules?
finitefinite
finiteffinitef
finitelfinitel
flistxattrflistxattr
flockflock
flockfileflockfile
floorfloor
floorffloorf
floorlfloorl
fmafma
fmaffmaf
fmalfmal
fmaxfmax
fmaxffmaxf
fmaximumfmaximum
fmaximum_magfmaximum_mag
fmaximum_mag_numfmaximum_mag_num
fmaximum_mag_numffmaximum_mag_numf
fmaximum_mag_numlfmaximum_mag_numl
fmaximum_magffmaximum_magf
fmaximum_maglfmaximum_magl
fmaximum_numfmaximum_num
fmaximum_numffmaximum_numf
fmaximum_numlfmaximum_numl
fmaximumffmaximumf
fmaximumlfmaximuml
fmaxlfmaxl
fmaxmagfmaxmag
fmaxmagffmaxmagf
fmaxmaglfmaxmagl
fmemopenfmemopen
fminfmin
fminffminf
fminimumfminimum
fminimum_magfminimum_mag
fminimum_mag_numfminimum_mag_num
fminimum_mag_numffminimum_mag_numf
fminimum_mag_numlfminimum_mag_numl
fminimum_magffminimum_magf
fminimum_maglfminimum_magl
fminimum_numfminimum_num
fminimum_numffminimum_numf
fminimum_numlfminimum_numl
fminimumffminimumf
fminimumlfminimuml
fminlfminl
fminmagfminmag
fminmagffminmagf
fminmaglfminmagl
fmodfmod
fmodffmodf
fmodlfmodl
fmtmsgfmtmsg
fmulfmul
fmullfmull
fnmatchfnmatch
fopenfopen
fopencookiefopencookie
forkfork
forkptyforkpty
fpathconffpathconf
fpclassifyfpclassify
fprintffprintf
fputcfputc
fputc_unlockedfputc_unlocked
fputsfputs
fputs_unlockedfputs_unlocked
fputwcfputwc
fputwc_unlockedfputwc_unlocked
fputwsfputws
fputws_unlockedfputws_unlocked
freadfread
fread_unlockedfread_unlocked
freefree
FREESafe Allocation Macros
free_aligned_sizedfree_aligned_sized
free_sizedfree_sized
freeaddrinfofreeaddrinfo
freeifaddrsfreeifaddrs
freelocalefreelocale
fremovexattrfremovexattr
freopenfreopen
frexpfrexp
frexpffrexpf
frexplfrexpl
fromfpfromfp
fromfpffromfpf
fromfplfromfpl
fromfpxfromfpx
fromfpxffromfpxf
fromfpxlfromfpxl
fscanffscanf
fsconfigfsconfig
fseekfseek
fseekofseeko
fsetposfsetpos
fsetxattrfsetxattr
fsmountfsmount
fsopenfsopen
fspickfspick
fsqrtfsqrt
fsqrtlfsqrtl
fstatfstat
fstatatfstatat
fstatfsfstatfs
fstatvfsfstatvfs
fsubfsub
fsublfsubl
fsyncfsync
ftellftell
ftelloftello
ftimeftime
ftokftok
ftruncateftruncate
ftrylockfileftrylockfile
fts_childrenfts_children
fts_closefts_close
fts_openfts_open
fts_readfts_read
fts_setfts_set
ftwftw
funlockfilefunlockfile
futimensfutimens
futimesfutimes
futimesatfutimesat
fwidefwide
fwprintffwprintf
fwritefwrite
fwrite_unlockedfwrite_unlocked
fwscanffwscanf
G
gai_strerrorgai_strerror
gammagamma
gammafgammaf
gammalgammal
gcdgcd
gcvtgcvt
get_avphys_pagesget_avphys_pages
get_current_dir_nameget_current_dir_name
get_myaddressget_myaddress
get_nprocsget_nprocs
get_nprocs_confget_nprocs_conf
get_phys_pagesget_phys_pages
getaddrinfogetaddrinfo
getaliasbynamegetaliasbyname
getaliasbyname_rgetaliasbyname_r
getaliasentgetaliasent
getaliasent_rgetaliasent_r
getauxvalgetauxval
getcgetc
getc_unlockedgetc_unlocked
getchargetchar
getchar_unlockedgetchar_unlocked
getcontextgetcontext
getcpugetcpu
getcwdgetcwd
getdategetdate
getdate_errgetdate_err
getdate_rgetdate_r
getdelimgetdelim
getdirentriesgetdirentries
getdomainnamegetdomainname
getdtablesizegetdtablesize
getegidgetegid
getentropygetentropy
getenvgetenv
geteuidgeteuid
getfilecongetfilecon
getfsentgetfsent
getfsfilegetfsfile
getfsspecgetfsspec
getgidgetgid
getgrentgetgrent
getgrent_rgetgrent_r
getgrgidgetgrgid
getgrgid_rgetgrgid_r
getgrnamgetgrnam
getgrnam_rgetgrnam_r
getgrouplistgetgrouplist
getgroupsgetgroups
gethostbyaddrgethostbyaddr
gethostbyaddr_rgethostbyaddr_r
gethostbynamegethostbyname
gethostbyname_rgethostbyname_r
gethostbyname2gethostbyname2
gethostbyname2_rgethostbyname2_r
gethostentgethostent
gethostent_rgethostent_r
gethostidgethostid
gethostnamegethostname
getifaddrsgetifaddrs
getipv4sourcefiltergetipv4sourcefilter
getitimergetitimer
getlinegetline
getloadavggetloadavg
getlocalename_lgetlocalename_l
getlogingetlogin
getlogin_rgetlogin_r
getmntentgetmntent
getmntent_rgetmntent_r
getmsggetmsg
getnameinfogetnameinfo
getnetbyaddrgetnetbyaddr
getnetbyaddr_rgetnetbyaddr_r
getnetbynamegetnetbyname
getnetbyname_rgetnetbyname_r
getnetentgetnetent
getnetent_rgetnetent_r
getnetgrentgetnetgrent
getnetgrent_rgetnetgrent_r
getnetnamegetnetname
getoptgetopt
getopt_longgetopt_long
getopt_long_onlygetopt_long_only
getpagesizegetpagesize
getpassgetpass
getpayloadgetpayload
getpayloadfgetpayloadf
getpayloadlgetpayloadl
getpeernamegetpeername
getpgidgetpgid
getpgrpgetpgrp
getpidgetpid
getpmsggetpmsg
getppidgetppid
getprioritygetpriority
getprognameprogname and getprogname
getprotobynamegetprotobyname
getprotobyname_rgetprotobyname_r
getprotobynumbergetprotobynumber
getprotobynumber_rgetprotobynumber_r
getprotoentgetprotoent
getprotoent_rgetprotoent_r
getptgetpt
getpublickeygetpublickey
getpwgetpw
getpwentgetpwent
getpwent_rgetpwent_r
getpwnamgetpwnam
getpwnam_rgetpwnam_r
getpwuidgetpwuid
getpwuid_rgetpwuid_r
getrandomgetrandom
getresgidgetresgid
getresuidgetresuid
getrlimitgetrlimit
getrpcbynamegetrpcbyname
getrpcbyname_rgetrpcbyname_r
getrpcbynumbergetrpcbynumber
getrpcbynumber_rgetrpcbynumber_r
getrpcentgetrpcent
getrpcent_rgetrpcent_r
getrpcportgetrpcport
getrusagegetrusage
getsgets
getsecretkeygetsecretkey
getservbynamegetservbyname
getservbyname_rgetservbyname_r
getservbyportgetservbyport
getservbyport_rgetservbyport_r
getserventgetservent
getservent_rgetservent_r
getsgentgetsgent
getsgent_rgetsgent_r
getsgnamgetsgnam
getsgnam_rgetsgnam_r
getsidgetsid
getsocknamegetsockname
getsockoptgetsockopt
getsourcefiltergetsourcefilter
getspentgetspent
getspent_rgetspent_r
getspnamgetspnam
getspnam_rgetspnam_r
getsuboptgetsubopt
gettextgettext
gettext_lgettext_l
gettextize, caveatgettextize and autopoint
gettidgettid
gettimeofdaygettimeofday
getttyentgetttyent
getttynamgetttynam
getuidgetuid
getumaskgetumask
getusershellgetusershell
getutentgetutent
getutent_rgetutent_r
getutidgetutid
getutid_rgetutid_r
getutlinegetutline
getutline_rgetutline_r
getutmpgetutmp
getutmpxgetutmpx
getutxentgetutxent
getutxidgetutxid
getutxlinegetutxline
getwgetw
getwcgetwc
getwc_unlockedgetwc_unlocked
getwchargetwchar
getwchar_unlockedgetwchar_unlocked
getwdgetwd
getxattrgetxattr
gitloggitlog-to-changelog
globglob
glob_pattern_pglob_pattern_p
globfreeglobfree
gmtimegmtime
gmtime_rgmtime_r
gnu_dev_majorgnu_dev_major
gnu_dev_makedevgnu_dev_makedev
gnu_dev_minorgnu_dev_minor
gnu_get_libc_releasegnu_get_libc_release
gnu_get_libc_versiongnu_get_libc_version
gnulib-toolInvoking gnulib-tool
grantptgrantpt
GrepPredefined Syntaxes
group_membergroup_member
groupingGrouping Operators
gsignalgsignal
H
h_errnoh_errno
hasmntopthasmntopt
hcreatehcreate
hcreate_rhcreate_r
hdestroyhdestroy
hdestroy_rhdestroy_r
header file include protectionHeader files
Header files and C++Header files
herrorherror
host2netnamehost2netname
hsearchhsearch
hsearch_rhsearch_r
hstrerrorhstrerror
htobe16htobe16
htobe32htobe32
htobe64htobe64
htole16htole16
htole32htole32
htole64htole64
htonlhtonl
htonshtons
hypothypot
hypotfhypotf
hypotlhypotl
I
iconviconv
iconv_closeiconv_close
iconv_openiconv_open
if_freenameindexif_freenameindex
if_indextonameif_indextoname
if_nameindexif_nameindex
if_nametoindexif_nametoindex
ilogbilogb
ilogbfilogbf
ilogblilogbl
imaxabsimaxabs
imaxdivimaxdiv
in6addr_anyin6addr_any
in6addr_loopbackin6addr_loopback
index_index
inet_addrinet_addr
inet_atoninet_aton
inet_lnaofinet_lnaof
inet_makeaddrinet_makeaddr
inet_net_ntopinet_net_ntop
inet_net_ptoninet_net_pton
inet_netofinet_netof
inet_networkinet_network
inet_nsap_addrinet_nsap_addr
inet_nsap_ntoainet_nsap_ntoa
inet_ntoainet_ntoa
inet_ntopinet_ntop
inet_ptoninet_pton
inet6_opt_appendinet6_opt_append
inet6_opt_findinet6_opt_find
inet6_opt_finishinet6_opt_finish
inet6_opt_get_valinet6_opt_get_val
inet6_opt_initinet6_opt_init
inet6_opt_nextinet6_opt_next
inet6_opt_set_valinet6_opt_set_val
inet6_option_allocinet6_option_alloc
inet6_option_appendinet6_option_append
inet6_option_findinet6_option_find
inet6_option_initinet6_option_init
inet6_option_nextinet6_option_next
inet6_option_spaceinet6_option_space
inet6_rth_addinet6_rth_add
inet6_rth_getaddrinet6_rth_getaddr
inet6_rth_initinet6_rth_init
inet6_rth_reverseinet6_rth_reverse
inet6_rth_segmentsinet6_rth_segments
inet6_rth_spaceinet6_rth_space
initgroupsinitgroups
initial importInitial import
initstateinitstate
initstate_rinitstate_r
inlinestatic inline
inlineextern inline
innetgrinnetgr
inotify_add_watchinotify_add_watch
inotify_initinotify_init
inotify_init1inotify_init1
inotify_rm_watchinotify_rm_watch
insqueinsque
intSafe Allocation Macros
intSafe Allocation Macros
intSafe Allocation Macros
INT_ADD_OKChecking Integer Overflow
INT_ADD_OVERFLOWInteger Type Overflow
INT_ADD_RANGE_OVERFLOWInteger Range Overflow
INT_ADD_WRAPVWraparound Arithmetic
INT_BUFSIZE_BOUNDInteger Bounds
INT_DIVIDE_OVERFLOWInteger Type Overflow
INT_DIVIDE_RANGE_OVERFLOWInteger Range Overflow
INT_LEFT_SHIFT_OVERFLOWInteger Type Overflow
INT_LEFT_SHIFT_RANGE_OVERFLOWInteger Range Overflow
INT_MULTIPLY_OKChecking Integer Overflow
INT_MULTIPLY_OVERFLOWInteger Type Overflow
INT_MULTIPLY_RANGE_OVERFLOWInteger Range Overflow
INT_MULTIPLY_WRAPVWraparound Arithmetic
INT_NEGATE_OVERFLOWInteger Type Overflow
INT_NEGATE_RANGE_OVERFLOWInteger Range Overflow
INT_PROMOTEArithmetic Type Conversion
INT_REMAINDER_OVERFLOWInteger Type Overflow
INT_REMAINDER_RANGE_OVERFLOWInteger Range Overflow
INT_STRLEN_BOUNDInteger Bounds
INT_SUBTRACT_OKChecking Integer Overflow
INT_SUBTRACT_OVERFLOWInteger Type Overflow
INT_SUBTRACT_RANGE_OVERFLOWInteger Range Overflow
INT_SUBTRACT_WRAPVWraparound Arithmetic
integer arithmetic portabilityUnsupported Platforms
integer boundsInteger Bounds
integer overflowInteger Properties
integer overflow checkingChecking Integer Overflow
integer propertiesInteger Properties
integer range overflowInteger Range Overflow
integer type conversionArithmetic Type Conversion
integer type overflowInteger Type Overflow
interval expressionInterval Operators
invoking gnulib-toolInvoking gnulib-tool
ioctlioctl
iopermioperm
iopliopl
isalnumisalnum
isalnum_lisalnum_l
isalphaisalpha
isalpha_lisalpha_l
isasciiisascii
isastreamisastream
isattyisatty
isblankisblank
isblank_lisblank_l
iscntrliscntrl
iscntrl_liscntrl_l
isctypeisctype
isdigitisdigit
isdigit_lisdigit_l
isfdtypeisfdtype
isfiniteisfinite
isgraphisgraph
isgraph_lisgraph_l
isgreaterisgreater
isgreaterequalisgreaterequal
isinfisinf
isinffisinff
isinflisinfl
islessisless
islessequalislessequal
islessgreaterislessgreater
islowerislower
islower_lislower_l
isnanisnan
isnanfisnanf
isnanlisnanl
isnormalisnormal
isprintisprint
isprint_lisprint_l
ispunctispunct
ispunct_lispunct_l
isspaceisspace
isspace_lisspace_l
isunorderedisunordered
isupperisupper
isupper_lisupper_l
iswalnumiswalnum
iswalnum_liswalnum_l
iswalphaiswalpha
iswalpha_liswalpha_l
iswblankiswblank
iswblank_liswblank_l
iswcntrliswcntrl
iswcntrl_liswcntrl_l
iswctypeiswctype
iswctype_liswctype_l
iswdigitiswdigit
iswdigit_liswdigit_l
iswgraphiswgraph
iswgraph_liswgraph_l
iswloweriswlower
iswlower_liswlower_l
iswprintiswprint
iswprint_liswprint_l
iswpunctiswpunct
iswpunct_liswpunct_l
iswspaceiswspace
iswspace_liswspace_l
iswupperiswupper
iswupper_liswupper_l
iswxdigitiswxdigit
iswxdigit_liswxdigit_l
isxdigitisxdigit
isxdigit_lisxdigit_l
J
j0j0
j0fj0f
j0lj0l
j1j1
j1fj1f
j1lj1l
jnjn
jnfjnf
jnljnl
jrand48jrand48
jrand48_rjrand48_r
K
key_decryptsessionkey_decryptsession
key_decryptsession_pkkey_decryptsession_pk
key_encryptsessionkey_encryptsession
key_encryptsession_pkkey_encryptsession_pk
key_gendeskey_gendes
key_get_convkey_get_conv
key_secretkey_is_setkey_secretkey_is_set
key_setsecretkey_setsecret
killkill
kill_dependencykill_dependency
killpgkillpg
klogctlklogctl
L
l64al64a
labslabs
lchmodlchmod
lchownlchown
lckpwdflckpwdf
lcong48lcong48
lcong48_rlcong48_r
LD DEF filesVisual Studio Compatibility
ldexpldexp
ldexpfldexpf
ldexplldexpl
ldivldiv
le16tohle16toh
le32tohle32toh
le64tohle64toh
lfindlfind
lgammalgamma
lgamma_rlgamma_r
lgammaflgammaf
lgammaf_rlgammaf_r
lgammallgammal
lgammal_rlgammal_r
lgetfileconlgetfilecon
lgetxattrlgetxattr
linklink
linkatlinkat
lio_listiolio_listio
listenlisten
listxattrlistxattr
llabsllabs
lldivlldiv
llistxattrllistxattr
llogbllogb
llogbfllogbf
llogblllogbl
llrintllrint
llrintfllrintf
llrintlllrintl
llroundllround
llroundfllroundf
llroundlllroundl
loc1loc1
loc2loc2
localeconvlocaleconv
localtimelocaltime
localtime_rlocaltime_r
lockflockf
locslocs
loglog
log10log10
log10flog10f
log10llog10l
log10p1log10p1
log10p1flog10p1f
log10p1llog10p1l
log1plog1p
log1pflog1pf
log1pllog1pl
log2log2
log2flog2f
log2llog2l
log2p1log2p1
log2p1flog2p1f
log2p1llog2p1l
logblogb
logbflogbf
logbllogbl
logflogf
loginlogin
login_ttylogin_tty
logllogl
logp1logp1
logp1flogp1f
logp1llogp1l
long-running tests modulesExtra tests modules
longjmplongjmp
lrand48lrand48
lrand48_rlrand48_r
lremovexattrlremovexattr
lrintlrint
lrintflrintf
lrintllrintl
lroundlround
lroundflroundf
lroundllroundl
lsearchlsearch
lseeklseek
lsetxattrlsetxattr
lstatlstat
lutimeslutimes
M
madvisemadvise
makecontextmakecontext
making releasesmaintainer-makefile
mallinfomallinfo
mallinfo2mallinfo2
mallocmalloc
mallocGNU Regular Expression Compiling
malloc_infomalloc_info
malloc_statsmalloc_stats
malloc_trimmalloc_trim
malloc_usable_sizemalloc_usable_size
malloptmallopt
matching listList Operators
matching newlineList Operators
matching with GNU functionsGNU Matching
math_errhandlingmath_errhandling
matherrmatherr
mblenmblen
mbrlenmbrlen
mbrtoc16mbrtoc16
mbrtoc32mbrtoc32
mbrtoc8mbrtoc8
mbrtowcmbrtowc
mbsinitmbsinit
mbsnrtowcsmbsnrtowcs
mbsrtowcsmbsrtowcs
mbstowcsmbstowcs
mbtowcmbtowc
mcheckmcheck
mcheck_check_allmcheck_check_all
mcheck_pedanticmcheck_pedantic
memalignmemalign
memalignmentmemalignment
memccpymemccpy
memchrmemchr
memcmpmemcmp
memcpymemcpy
memfd_creatememfd_create
memfrobmemfrob
memmemmemmem
memmovememmove
Memory allocation failureOut of memory handling
mempcpymempcpy
memrchrmemrchr
memsetmemset
memset_explicitmemset_explicit
mincoremincore
mkdirmkdir
mkdiratmkdirat
mkdtempmkdtemp
mkfifomkfifo
mkfifoatmkfifoat
mknodmknod
mknodatmknodat
mkostempmkostemp
mkostempsmkostemps
mkstempmkstemp
mkstempsmkstemps
mktempmktemp
mktimemktime
mlockmlock
mlock2mlock2
mlockallmlockall
mmapmmap
modfmodf
modffmodff
modflmodfl
monstartupmonstartup
mountmount
mount_setattrmount_setattr
move_mountmove_mount
mprobemprobe
mprotectmprotect
mq_closemq_close
mq_getattrmq_getattr
mq_notifymq_notify
mq_openmq_open
mq_receivemq_receive
mq_sendmq_send
mq_setattrmq_setattr
mq_timedreceivemq_timedreceive
mq_timedsendmq_timedsend
mq_unlinkmq_unlink
mrand48mrand48
mrand48_rmrand48_r
mremapmremap
msgctlmsgctl
msggetmsgget
msgrcvmsgrcv
msgsndmsgsnd
msyncmsync
mtracemtrace
mtx_destroymtx_destroy
mtx_initmtx_init
mtx_lockmtx_lock
mtx_timedlockmtx_timedlock
mtx_trylockmtx_trylock
mtx_unlockmtx_unlock
multibyte localeC strings
munlockmunlock
munlockallmunlockall
munmapmunmap
muntracemuntrace
N
name_to_handle_atname_to_handle_at
nannan
nanfnanf
nanlnanl
nanosleepnanosleep
nearbyintnearbyint
nearbyintfnearbyintf
nearbyintlnearbyintl
netname2hostnetname2host
netname2usernetname2user
newlocalenewlocale
NEWS, NEWS.md filesmaintainer-makefile
nextafternextafter
nextafterfnextafterf
nextafterlnextafterl
nextdownnextdown
nextdownfnextdownf
nextdownlnextdownl
nexttowardnexttoward
nexttowardfnexttowardf
nexttowardlnexttowardl
nextupnextup
nextupfnextupf
nextuplnextupl
nftwnftw
ngettextngettext
ngettext_lngettext_l
nicenice
nis_addnis_add
nis_add_entrynis_add_entry
nis_addmembernis_addmember
nis_checkpointnis_checkpoint
nis_clone_objectnis_clone_object
nis_creategroupnis_creategroup
nis_destroy_objectnis_destroy_object
nis_destroygroupnis_destroygroup
nis_dir_cmpnis_dir_cmp
nis_domain_ofnis_domain_of
nis_domain_of_rnis_domain_of_r
nis_first_entrynis_first_entry
nis_freenamesnis_freenames
nis_freeresultnis_freeresult
nis_freeservlistnis_freeservlist
nis_freetagsnis_freetags
nis_getnamesnis_getnames
nis_getservlistnis_getservlist
nis_ismembernis_ismember
nis_leaf_ofnis_leaf_of
nis_leaf_of_rnis_leaf_of_r
nis_lerrornis_lerror
nis_listnis_list
nis_local_directorynis_local_directory
nis_local_groupnis_local_group
nis_local_hostnis_local_host
nis_local_principalnis_local_principal
nis_lookupnis_lookup
nis_mkdirnis_mkdir
nis_modifynis_modify
nis_modify_entrynis_modify_entry
nis_name_ofnis_name_of
nis_name_of_rnis_name_of_r
nis_next_entrynis_next_entry
nis_perrornis_perror
nis_pingnis_ping
nis_print_directorynis_print_directory
nis_print_entrynis_print_entry
nis_print_groupnis_print_group
nis_print_group_entrynis_print_group_entry
nis_print_linknis_print_link
nis_print_objectnis_print_object
nis_print_resultnis_print_result
nis_print_rightsnis_print_rights
nis_print_tablenis_print_table
nis_removenis_remove
nis_remove_entrynis_remove_entry
nis_removemembernis_removemember
nis_rmdirnis_rmdir
nis_servstatenis_servstate
nis_sperrnonis_sperrno
nis_sperrornis_sperror
nis_sperror_rnis_sperror_r
nis_statsnis_stats
nis_verifygroupnis_verifygroup
nl_langinfonl_langinfo
nl_langinfo_lnl_langinfo_l
nonmatching listList Operators
not_bol field in pattern bufferMatch-beginning-of-line Operator
nrand48nrand48
nrand48_rnrand48_r
ns_name_compressns_name_compress
ns_name_ntopns_name_ntop
ns_name_packns_name_pack
ns_name_ptonns_name_pton
ns_name_skipns_name_skip
ns_name_uncompressns_name_uncompress
ns_name_unpackns_name_unpack
ntohlntohl
ntohsntohs
ntp_adjtimentp_adjtime
ntp_gettimentp_gettime
ntp_gettimexntp_gettimex
null pointernullptr
null pointer typestddef.h
num_regs in struct re_registersUsing Registers
O
Obsolete modulesObsolete modules
obstack_alloc_failed_handlerobstack_alloc_failed_handler
obstack_exit_failureobstack_exit_failure
obstack_freeobstack_free
obstack_printfobstack_printf
obstack_vprintfobstack_vprintf
on_exiton_exit
openopen
open_by_handle_atopen_by_handle_at
open_memstreamopen_memstream
open_treeopen_tree
open_wmemstreamopen_wmemstream
open-group operator and ‘^’Match-beginning-of-line Operator
openatopenat
openat2openat2
opendiropendir
openlogopenlog
openptyopenpty
optargoptarg
opterropterr
optindoptind
optoptoptopt
or operatorAlternation Operator
Out of Memory handlingOut of memory handling
overflow, integerInteger Properties
overflow, integer rangeInteger Range Overflow
overflow, integer typeInteger Type Overflow
P
parenthesizingGrouping Operators
parse_printf_formatparse_printf_format
pathconfpathconf
pattern buffer initializationGNU Regular Expression Compiling
pattern buffer, definition ofGNU Pattern Buffers
pausepause
pclosepclose
perrorperror
personalitypersonality
pidfd_getfdpidfd_getfd
pidfd_getpidpidfd_getpid
pidfd_openpidfd_open
pidfd_send_signalpidfd_send_signal
pidfd_spawnpidfd_spawn
pidfd_spawnppidfd_spawnp
pipepipe
pipe2pipe2
pkey_allocpkey_alloc
pkey_freepkey_free
pkey_getpkey_get
pkey_mprotectpkey_mprotect
pkey_setpkey_set
pmap_getmapspmap_getmaps
pmap_getportpmap_getport
pmap_rmtcallpmap_rmtcall
pmap_setpmap_set
pmap_unsetpmap_unset
pollpoll
popenpopen
portability, integer arithmeticUnsupported Platforms
POSIX AwkPredefined Syntaxes
posix_closeposix_close
posix_devctlposix_devctl
posix_fadviseposix_fadvise
posix_fallocateposix_fallocate
posix_getdentsposix_getdents
posix_madviseposix_madvise
posix_mem_offsetposix_mem_offset
posix_memalignposix_memalign
posix_openptposix_openpt
posix_spawnposix_spawn
posix_spawn_file_actions_addchdirposix_spawn_file_actions_addchdir
posix_spawn_file_actions_addchdir_npposix_spawn_file_actions_addchdir_np
posix_spawn_file_actions_addcloseposix_spawn_file_actions_addclose
posix_spawn_file_actions_addclosefrom_npposix_spawn_file_actions_addclosefrom_np
posix_spawn_file_actions_adddup2posix_spawn_file_actions_adddup2
posix_spawn_file_actions_addfchdirposix_spawn_file_actions_addfchdir
posix_spawn_file_actions_addfchdir_npposix_spawn_file_actions_addfchdir_np
posix_spawn_file_actions_addopenposix_spawn_file_actions_addopen
posix_spawn_file_actions_addtcsetpgrp_npposix_spawn_file_actions_addtcsetpgrp_np
posix_spawn_file_actions_destroyposix_spawn_file_actions_destroy
posix_spawn_file_actions_initposix_spawn_file_actions_init
posix_spawnattr_destroyposix_spawnattr_destroy
posix_spawnattr_getcgroup_npposix_spawnattr_getcgroup_np
posix_spawnattr_getflagsposix_spawnattr_getflags
posix_spawnattr_getpgroupposix_spawnattr_getpgroup
posix_spawnattr_getschedparamposix_spawnattr_getschedparam
posix_spawnattr_getschedpolicyposix_spawnattr_getschedpolicy
posix_spawnattr_getsigdefaultposix_spawnattr_getsigdefault
posix_spawnattr_getsigmaskposix_spawnattr_getsigmask
posix_spawnattr_initposix_spawnattr_init
posix_spawnattr_setcgroup_npposix_spawnattr_setcgroup_np
posix_spawnattr_setflagsposix_spawnattr_setflags
posix_spawnattr_setpgroupposix_spawnattr_setpgroup
posix_spawnattr_setschedparamposix_spawnattr_setschedparam
posix_spawnattr_setschedpolicyposix_spawnattr_setschedpolicy
posix_spawnattr_setsigdefaultposix_spawnattr_setsigdefault
posix_spawnattr_setsigmaskposix_spawnattr_setsigmask
posix_spawnpposix_spawnp
posix_trace_attr_destroyposix_trace_attr_destroy
posix_trace_attr_getclockresposix_trace_attr_getclockres
posix_trace_attr_getcreatetimeposix_trace_attr_getcreatetime
posix_trace_attr_getgenversionposix_trace_attr_getgenversion
posix_trace_attr_getinheritedposix_trace_attr_getinherited
posix_trace_attr_getlogfullpolicyposix_trace_attr_getlogfullpolicy
posix_trace_attr_getlogsizeposix_trace_attr_getlogsize
posix_trace_attr_getmaxdatasizeposix_trace_attr_getmaxdatasize
posix_trace_attr_getmaxsystemeventsizeposix_trace_attr_getmaxsystemeventsize
posix_trace_attr_getmaxusereventsizeposix_trace_attr_getmaxusereventsize
posix_trace_attr_getnameposix_trace_attr_getname
posix_trace_attr_getstreamfullpolicyposix_trace_attr_getstreamfullpolicy
posix_trace_attr_getstreamsizeposix_trace_attr_getstreamsize
posix_trace_attr_initposix_trace_attr_init
posix_trace_attr_setinheritedposix_trace_attr_setinherited
posix_trace_attr_setlogfullpolicyposix_trace_attr_setlogfullpolicy
posix_trace_attr_setlogsizeposix_trace_attr_setlogsize
posix_trace_attr_setmaxdatasizeposix_trace_attr_setmaxdatasize
posix_trace_attr_setnameposix_trace_attr_setname
posix_trace_attr_setstreamfullpolicyposix_trace_attr_setstreamfullpolicy
posix_trace_attr_setstreamsizeposix_trace_attr_setstreamsize
posix_trace_clearposix_trace_clear
posix_trace_closeposix_trace_close
posix_trace_createposix_trace_create
posix_trace_create_withlogposix_trace_create_withlog
posix_trace_eventposix_trace_event
posix_trace_eventid_equalposix_trace_eventid_equal
posix_trace_eventid_get_nameposix_trace_eventid_get_name
posix_trace_eventid_openposix_trace_eventid_open
posix_trace_eventset_addposix_trace_eventset_add
posix_trace_eventset_delposix_trace_eventset_del
posix_trace_eventset_emptyposix_trace_eventset_empty
posix_trace_eventset_fillposix_trace_eventset_fill
posix_trace_eventset_ismemberposix_trace_eventset_ismember
posix_trace_eventtypelist_getnext_idposix_trace_eventtypelist_getnext_id
posix_trace_eventtypelist_rewindposix_trace_eventtypelist_rewind
posix_trace_flushposix_trace_flush
posix_trace_get_attrposix_trace_get_attr
posix_trace_get_filterposix_trace_get_filter
posix_trace_get_statusposix_trace_get_status
posix_trace_getnext_eventposix_trace_getnext_event
posix_trace_openposix_trace_open
posix_trace_rewindposix_trace_rewind
posix_trace_set_filterposix_trace_set_filter
posix_trace_shutdownposix_trace_shutdown
posix_trace_startposix_trace_start
posix_trace_stopposix_trace_stop
posix_trace_timedgetnext_eventposix_trace_timedgetnext_event
posix_trace_trid_eventid_openposix_trace_trid_eventid_open
posix_trace_trygetnext_eventposix_trace_trygetnext_event
posix_typed_mem_get_infoposix_typed_mem_get_info
posix_typed_mem_openposix_typed_mem_open
powpow
pow10pow10
pow10fpow10f
pow10lpow10l
powfpowf
powlpowl
pownpown
pownfpownf
pownlpownl
powrpowr
powrfpowrf
powrlpowrl
ppollppoll
prctlprctl
preadpread
preadvpreadv
preadv2preadv2
printfprintf
printf_sizeprintf_size
printf_size_infoprintf_size_info
privileged tests modulesExtra tests modules
prlimitprlimit
process_madviseprocess_madvise
process_mreleaseprocess_mrelease
process_vm_readvprocess_vm_readv
process_vm_writevprocess_vm_writev
profilprofil
program_invocation_nameprogram_invocation_name
program_invocation_short_nameprogram_invocation_short_name
program_nameprogname and getprogname
pselectpselect
psiginfopsiginfo
psignalpsignal
pthread_atforkpthread_atfork
pthread_attr_destroypthread_attr_destroy
pthread_attr_getaffinity_nppthread_attr_getaffinity_np
pthread_attr_getdetachstatepthread_attr_getdetachstate
pthread_attr_getguardsizepthread_attr_getguardsize
pthread_attr_getinheritschedpthread_attr_getinheritsched
pthread_attr_getschedparampthread_attr_getschedparam
pthread_attr_getschedpolicypthread_attr_getschedpolicy
pthread_attr_getscopepthread_attr_getscope
pthread_attr_getsigmask_nppthread_attr_getsigmask_np
pthread_attr_getstackpthread_attr_getstack
pthread_attr_getstackaddrpthread_attr_getstackaddr
pthread_attr_getstacksizepthread_attr_getstacksize
pthread_attr_initpthread_attr_init
pthread_attr_setaffinity_nppthread_attr_setaffinity_np
pthread_attr_setdetachstatepthread_attr_setdetachstate
pthread_attr_setguardsizepthread_attr_setguardsize
pthread_attr_setinheritschedpthread_attr_setinheritsched
pthread_attr_setschedparampthread_attr_setschedparam
pthread_attr_setschedpolicypthread_attr_setschedpolicy
pthread_attr_setscopepthread_attr_setscope
pthread_attr_setsigmask_nppthread_attr_setsigmask_np
pthread_attr_setstackpthread_attr_setstack
pthread_attr_setstackaddrpthread_attr_setstackaddr
pthread_attr_setstacksizepthread_attr_setstacksize
pthread_barrier_destroypthread_barrier_destroy
pthread_barrier_initpthread_barrier_init
pthread_barrier_waitpthread_barrier_wait
pthread_barrierattr_destroypthread_barrierattr_destroy
pthread_barrierattr_getpsharedpthread_barrierattr_getpshared
pthread_barrierattr_initpthread_barrierattr_init
pthread_barrierattr_setpsharedpthread_barrierattr_setpshared
pthread_cancelpthread_cancel
pthread_cleanup_poppthread_cleanup_pop
pthread_cleanup_pushpthread_cleanup_push
pthread_clockjoin_nppthread_clockjoin_np
pthread_cond_broadcastpthread_cond_broadcast
pthread_cond_clockwaitpthread_cond_clockwait
pthread_cond_destroypthread_cond_destroy
pthread_cond_initpthread_cond_init
pthread_cond_signalpthread_cond_signal
pthread_cond_timedwaitpthread_cond_timedwait
pthread_cond_waitpthread_cond_wait
pthread_condattr_destroypthread_condattr_destroy
pthread_condattr_getclockpthread_condattr_getclock
pthread_condattr_getpsharedpthread_condattr_getpshared
pthread_condattr_initpthread_condattr_init
pthread_condattr_setclockpthread_condattr_setclock
pthread_condattr_setpsharedpthread_condattr_setpshared
pthread_createpthread_create
pthread_detachpthread_detach
pthread_equalpthread_equal
pthread_exitpthread_exit
pthread_getaffinity_nppthread_getaffinity_np
pthread_getattr_default_nppthread_getattr_default_np
pthread_getattr_nppthread_getattr_np
pthread_getconcurrencypthread_getconcurrency
pthread_getcpuclockidpthread_getcpuclockid
pthread_getname_nppthread_getname_np
pthread_getschedparampthread_getschedparam
pthread_getspecificpthread_getspecific
pthread_gettid_nppthread_gettid_np
pthread_joinpthread_join
pthread_key_createpthread_key_create
pthread_key_deletepthread_key_delete
pthread_killpthread_kill
pthread_kill_other_threads_nppthread_kill_other_threads_np
pthread_mutex_clocklockpthread_mutex_clocklock
pthread_mutex_consistentpthread_mutex_consistent
pthread_mutex_destroypthread_mutex_destroy
pthread_mutex_getprioceilingpthread_mutex_getprioceiling
pthread_mutex_initpthread_mutex_init
pthread_mutex_lockpthread_mutex_lock
pthread_mutex_setprioceilingpthread_mutex_setprioceiling
pthread_mutex_timedlockpthread_mutex_timedlock
pthread_mutex_trylockpthread_mutex_trylock
pthread_mutex_unlockpthread_mutex_unlock
pthread_mutexattr_destroypthread_mutexattr_destroy
pthread_mutexattr_getprioceilingpthread_mutexattr_getprioceiling
pthread_mutexattr_getprotocolpthread_mutexattr_getprotocol
pthread_mutexattr_getpsharedpthread_mutexattr_getpshared
pthread_mutexattr_getrobustpthread_mutexattr_getrobust
pthread_mutexattr_gettypepthread_mutexattr_gettype
pthread_mutexattr_initpthread_mutexattr_init
pthread_mutexattr_setprioceilingpthread_mutexattr_setprioceiling
pthread_mutexattr_setprotocolpthread_mutexattr_setprotocol
pthread_mutexattr_setpsharedpthread_mutexattr_setpshared
pthread_mutexattr_setrobustpthread_mutexattr_setrobust
pthread_mutexattr_settypepthread_mutexattr_settype
pthread_oncepthread_once
pthread_rwlock_clockrdlockpthread_rwlock_clockrdlock
pthread_rwlock_clockwrlockpthread_rwlock_clockwrlock
pthread_rwlock_destroypthread_rwlock_destroy
pthread_rwlock_initpthread_rwlock_init
pthread_rwlock_rdlockpthread_rwlock_rdlock
pthread_rwlock_timedrdlockpthread_rwlock_timedrdlock
pthread_rwlock_timedwrlockpthread_rwlock_timedwrlock
pthread_rwlock_tryrdlockpthread_rwlock_tryrdlock
pthread_rwlock_trywrlockpthread_rwlock_trywrlock
pthread_rwlock_unlockpthread_rwlock_unlock
pthread_rwlock_wrlockpthread_rwlock_wrlock
pthread_rwlockattr_destroypthread_rwlockattr_destroy
pthread_rwlockattr_getkind_nppthread_rwlockattr_getkind_np
pthread_rwlockattr_getpsharedpthread_rwlockattr_getpshared
pthread_rwlockattr_initpthread_rwlockattr_init
pthread_rwlockattr_setkind_nppthread_rwlockattr_setkind_np
pthread_rwlockattr_setpsharedpthread_rwlockattr_setpshared
pthread_selfpthread_self
pthread_setaffinity_nppthread_setaffinity_np
pthread_setattr_default_nppthread_setattr_default_np
pthread_setcancelstatepthread_setcancelstate
pthread_setcanceltypepthread_setcanceltype
pthread_setconcurrencypthread_setconcurrency
pthread_setname_nppthread_setname_np
pthread_setschedparampthread_setschedparam
pthread_setschedpriopthread_setschedprio
pthread_setspecificpthread_setspecific
pthread_sigmaskpthread_sigmask
pthread_sigqueuepthread_sigqueue
pthread_spin_destroypthread_spin_destroy
pthread_spin_initpthread_spin_init
pthread_spin_lockpthread_spin_lock
pthread_spin_trylockpthread_spin_trylock
pthread_spin_unlockpthread_spin_unlock
pthread_testcancelpthread_testcancel
pthread_timedjoin_nppthread_timedjoin_np
pthread_tryjoin_nppthread_tryjoin_np
ptraceptrace
ptsnameptsname
ptsname_rptsname_r
putcputc
putc_unlockedputc_unlocked
putcharputchar
putchar_unlockedputchar_unlocked
putenvputenv
putgrentputgrent
putmsgputmsg
putpmsgputpmsg
putpwentputpwent
putsputs
putsgentputsgent
putspentputspent
pututlinepututline
pututxlinepututxline
putwputw
putwcputwc
putwc_unlockedputwc_unlocked
putwcharputwchar
putwchar_unlockedputwchar_unlocked
pvallocpvalloc
pwritepwrite
pwritevpwritev
pwritev2pwritev2
Q
qecvtqecvt
qecvt_rqecvt_r
qfcvtqfcvt
qfcvt_rqfcvt_r
qgcvtqgcvt
qsortqsort
qsort_rqsort_r
quick_exitquick_exit
quotactlquotactl
quoteQuoting
quote_nQuoting
quoteargQuoting
quotearg_allocQuoting
QuotingQuoting
R
raiseraise
randrand
rand_rrand_r
randomrandom
random_rrandom_r
range argument to re_searchGNU Searching
rawmemchrrawmemchr
rcmdrcmd
rcmd_afrcmd_af
RE_BACKSLASH_ESCAPE_IN_LISTSyntax Bits
RE_BK_PLUS_QMSyntax Bits
RE_CHAR_CLASSESSyntax Bits
re_compre_comp
re_compBSD Regular Expression Compiling
re_compile_fastmapre_compile_fastmap
re_compile_fastmapSearching with Fastmaps
re_compile_patternre_compile_pattern
re_compile_patternGNU Regular Expression Compiling
RE_CONTEXT_INDEP_ANCHORSSyntax Bits
RE_CONTEXT_INDEP_ANCHORS (and ‘^’)Match-beginning-of-line Operator
RE_CONTEXT_INDEP_OPSSyntax Bits
RE_CONTEXT_INVALID_DUPSyntax Bits
RE_CONTEXT_INVALID_OPSSyntax Bits
RE_DEBUGSyntax Bits
RE_DOT_NEWLINESyntax Bits
RE_DOT_NOT_NULLSyntax Bits
re_execre_exec
re_execBSD Searching
RE_HAT_LISTS_NOT_NEWLINESyntax Bits
RE_ICASESyntax Bits
RE_INTERVALSSyntax Bits
RE_INVALID_INTERVAL_ORDSyntax Bits
RE_LIMITED_OPSSyntax Bits
re_matchre_match
re_matchGNU Matching
re_match_2re_match_2
re_match_2Matching/Searching with Split Data
RE_NEWLINE_ALTSyntax Bits
RE_NO_BK_BRACESSyntax Bits
RE_NO_BK_PARENSSyntax Bits
RE_NO_BK_REFSSyntax Bits
RE_NO_BK_VBARSyntax Bits
RE_NO_EMPTY_RANGESSyntax Bits
RE_NO_GNU_OPSSyntax Bits
RE_NO_POSIX_BACKTRACKINGSyntax Bits
RE_NO_SUBSyntax Bits
re_nsub field, set by re_compile_patternGNU Regular Expression Compiling
re_pattern_buffer definitionGNU Pattern Buffers
re_registersUsing Registers
re_searchre_search
re_searchGNU Searching
re_search_2re_search_2
re_search_2Matching/Searching with Split Data
re_set_registersre_set_registers
re_set_registersUsing Registers
re_set_syntaxre_set_syntax
re_syntax_optionsre_syntax_options
re_syntax_options initializationGNU Regular Expression Compiling
RE_UNMATCHED_RIGHT_PAREN_ORDSyntax Bits
readread
readaheadreadahead
readdirreaddir
readdir_rreaddir_r
readlinkreadlink
readlinkatreadlinkat
readvreadv
reallocrealloc
reallocarrayreallocarray
realpathrealpath
rebootreboot
recvrecv
recvfromrecvfrom
recvmmsgrecvmmsg
recvmsgrecvmsg
regcompregcomp
regerrorregerror
regex.hOverview
regexecregexec
regexp anchoringAnchoring Operators
regfreeregfree
regfreeFreeing GNU Pattern Buffers
register_printf_functionregister_printf_function
register_printf_modifierregister_printf_modifier
register_printf_specifierregister_printf_specifier
register_printf_typeregister_printf_type
regular expressions, syntax ofRegular Expression Syntax
remainderremainder
remainderfremainderf
remainderlremainderl
remap_file_pagesremap_file_pages
removeremove
removexattrremovexattr
remqueremque
remquoremquo
remquofremquof
remquolremquol
renamerename
renameatrenameat
renameat2renameat2
res_dnokres_dnok
res_hnokres_hnok
res_initres_init
res_mailokres_mailok
res_mkqueryres_mkquery
res_nmkqueryres_nmkquery
res_nqueryres_nquery
res_nquerydomainres_nquerydomain
res_nsearchres_nsearch
res_nsendres_nsend
res_ownokres_ownok
res_queryres_query
res_querydomainres_querydomain
res_searchres_search
res_sendres_send
revokerevoke
rewindrewind
rewinddirrewinddir
rexecrexec
rexec_afrexec_af
rindexrindex
rintrint
rintfrintf
rintlrintl
rmdirrmdir
rootnrootn
rootnfrootnf
rootnlrootnl
roundround
roundevenroundeven
roundevenfroundevenf
roundevenlroundevenl
roundfroundf
roundlroundl
rpc_createerrrpc_createerr
rpmatchrpmatch
rresvportrresvport
rresvport_afrresvport_af
rsqrtrsqrt
rsqrtfrsqrtf
rsqrtlrsqrtl
rtimertime
ruserokruserok
ruserok_afruserok_af
S
sbrksbrk
scalbscalb
scalbfscalbf
scalblscalbl
scalblnscalbln
scalblnfscalblnf
scalblnlscalblnl
scalbnscalbn
scalbnfscalbnf
scalbnlscalbnl
scandirscandir
scandiratscandirat
scanfscanf
sched_get_priority_maxsched_get_priority_max
sched_get_priority_minsched_get_priority_min
sched_getaffinitysched_getaffinity
sched_getattrsched_getattr
sched_getcpusched_getcpu
sched_getparamsched_getparam
sched_getschedulersched_getscheduler
sched_rr_get_intervalsched_rr_get_interval
sched_setaffinitysched_setaffinity
sched_setattrsched_setattr
sched_setparamsched_setparam
sched_setschedulersched_setscheduler
sched_yieldsched_yield
searching with GNU functionsGNU Searching
secure_getenvsecure_getenv
seed48seed48
seed48_rseed48_r
seekdirseekdir
selectselect
sem_clockwaitsem_clockwait
sem_closesem_close
sem_destroysem_destroy
sem_getvaluesem_getvalue
sem_initsem_init
sem_opensem_open
sem_postsem_post
sem_timedwaitsem_timedwait
sem_trywaitsem_trywait
sem_unlinksem_unlink
sem_waitsem_wait
semctlsemctl
semgetsemget
semopsemop
semtimedopsemtimedop
sendsend
sendfilesendfile
sendmmsgsendmmsg
sendmsgsendmsg
sendtosendto
setaliasentsetaliasent
setbufsetbuf
setbuffersetbuffer
setcontextsetcontext
setdomainnamesetdomainname
setegidsetegid
setenvsetenv
seteuidseteuid
setfsentsetfsent
setfsgidsetfsgid
setfsuidsetfsuid
setgidsetgid
setgrentsetgrent
setgroupssetgroups
sethostentsethostent
sethostidsethostid
sethostnamesethostname
setipv4sourcefiltersetipv4sourcefilter
setitimersetitimer
setjmpsetjmp
setkeysetkey
setlinebufsetlinebuf
setlocalesetlocale
setloginsetlogin
setlogmasksetlogmask
setmntentsetmntent
setnetentsetnetent
setnetgrentsetnetgrent
setnssetns
setpayloadsetpayload
setpayloadfsetpayloadf
setpayloadlsetpayloadl
setpayloadsigsetpayloadsig
setpayloadsigfsetpayloadsigf
setpayloadsiglsetpayloadsigl
setpgidsetpgid
setpgrpsetpgrp
setprioritysetpriority
setprotoentsetprotoent
setpwentsetpwent
setregidsetregid
setresgidsetresgid
setresuidsetresuid
setreuidsetreuid
setrlimitsetrlimit
setrpcentsetrpcent
setserventsetservent
setsgentsetsgent
setsidsetsid
setsockoptsetsockopt
setsourcefiltersetsourcefilter
setspentsetspent
setstatesetstate
setstate_rsetstate_r
settimeofdaysettimeofday
setttyentsetttyent
setuidsetuid
setusershellsetusershell
setutentsetutent
setutxentsetutxent
setvbufsetvbuf
setxattrsetxattr
sgetsgentsgetsgent
sgetsgent_rsgetsgent_r
sgetspentsgetspent
sgetspent_rsgetspent_r
shm_openshm_open
shm_unlinkshm_unlink
shmatshmat
shmctlshmctl
shmdtshmdt
shmgetshmget
shutdownshutdown
sig2strsig2str
sigabbrev_npsigabbrev_np
sigactionsigaction
sigaddsetsigaddset
sigaltstacksigaltstack
sigandsetsigandset
sigblocksigblock
sigdelsetsigdelset
sigdescr_npsigdescr_np
sigemptysetsigemptyset
sigfillsetsigfillset
siggetmasksiggetmask
sigholdsighold
sigignoresigignore
siginterruptsiginterrupt
sigisemptysetsigisemptyset
sigismembersigismember
siglongjmpsiglongjmp
signalsignal
signalfdsignalfd
signbitsignbit
signgamsigngam
significandsignificand
significandfsignificandf
significandlsignificandl
sigorsetsigorset
sigpausesigpause
sigpendingsigpending
sigprocmasksigprocmask
sigqueuesigqueue
sigrelsesigrelse
sigreturnsigreturn
sigsetsigset
sigsetjmpsigsetjmp
sigsetmasksigsetmask
sigstacksigstack
sigsuspendsigsuspend
sigtimedwaitsigtimedwait
sigvecsigvec
sigwaitsigwait
sigwaitinfosigwaitinfo
sinsin
sincossincos
sincosfsincosf
sincoslsincosl
sinfsinf
sinhsinh
sinhfsinhf
sinhlsinhl
sinlsinl
sinpisinpi
sinpifsinpif
sinpilsinpil
sleepsleep
snprintfsnprintf
sockatmarksockatmark
socketsocket
socketpairsocketpair
specificationSpecification
sprintfsprintf
sprofilsprofil
sqrtsqrt
sqrtfsqrtf
sqrtlsqrtl
srandsrand
srand48srand48
srand48_rsrand48_r
srandomsrandom
srandom_rsrandom_r
sscanfsscanf
ssignalssignal
ST_BLKSIZEstat-size
ST_NBLOCKSstat-size
ST_NBLOCKSIZEstat-size
start argument to re_searchGNU Searching
start in struct re_registersUsing Registers
statstat
statfsstatfs
static inlinestatic inline
statvfsstatvfs
statxstatx
stdc_bit_ceilstdc_bit_ceil
stdc_bit_floorstdc_bit_floor
stdc_bit_widthstdc_bit_width
stdc_count_onesstdc_count_ones
stdc_count_zerosstdc_count_zeros
stdc_first_leading_onestdc_first_leading_one
stdc_first_leading_zerostdc_first_leading_zero
stdc_first_trailing_onestdc_first_trailing_one
stdc_first_trailing_zerostdc_first_trailing_zero
stdc_has_single_bitstdc_has_single_bit
stdc_leading_onesstdc_leading_ones
stdc_leading_zerosstdc_leading_zeros
stdc_load8_aligned_bes16stdc_load8_aligned_bes16
stdc_load8_aligned_bes32stdc_load8_aligned_bes32
stdc_load8_aligned_bes64stdc_load8_aligned_bes64
stdc_load8_aligned_bes8stdc_load8_aligned_bes8
stdc_load8_aligned_beu16stdc_load8_aligned_beu16
stdc_load8_aligned_beu32stdc_load8_aligned_beu32
stdc_load8_aligned_beu64stdc_load8_aligned_beu64
stdc_load8_aligned_beu8stdc_load8_aligned_beu8
stdc_load8_aligned_les16stdc_load8_aligned_les16
stdc_load8_aligned_les32stdc_load8_aligned_les32
stdc_load8_aligned_les64stdc_load8_aligned_les64
stdc_load8_aligned_les8stdc_load8_aligned_les8
stdc_load8_aligned_leu16stdc_load8_aligned_leu16
stdc_load8_aligned_leu32stdc_load8_aligned_leu32
stdc_load8_aligned_leu64stdc_load8_aligned_leu64
stdc_load8_aligned_leu8stdc_load8_aligned_leu8
stdc_load8_bes16stdc_load8_bes16
stdc_load8_bes32stdc_load8_bes32
stdc_load8_bes64stdc_load8_bes64
stdc_load8_bes8stdc_load8_bes8
stdc_load8_beu16stdc_load8_beu16
stdc_load8_beu32stdc_load8_beu32
stdc_load8_beu64stdc_load8_beu64
stdc_load8_beu8stdc_load8_beu8
stdc_load8_les16stdc_load8_les16
stdc_load8_les32stdc_load8_les32
stdc_load8_les64stdc_load8_les64
stdc_load8_les8stdc_load8_les8
stdc_load8_leu16stdc_load8_leu16
stdc_load8_leu32stdc_load8_leu32
stdc_load8_leu64stdc_load8_leu64
stdc_load8_leu8stdc_load8_leu8
stdc_memreverse8stdc_memreverse8
stdc_memreverse8u16stdc_memreverse8u16
stdc_memreverse8u32stdc_memreverse8u32
stdc_memreverse8u64stdc_memreverse8u64
stdc_memreverse8u8stdc_memreverse8u8
stdc_rotate_leftstdc_rotate_left
stdc_rotate_left_ucstdc_rotate_left
stdc_rotate_left_uistdc_rotate_left
stdc_rotate_left_ulstdc_rotate_left
stdc_rotate_left_ullstdc_rotate_left
stdc_rotate_left_usstdc_rotate_left
stdc_rotate_rightstdc_rotate_right
stdc_rotate_right_ucstdc_rotate_right
stdc_rotate_right_uistdc_rotate_right
stdc_rotate_right_ulstdc_rotate_right
stdc_rotate_right_ullstdc_rotate_right
stdc_rotate_right_usstdc_rotate_right
stdc_store8_aligned_bes16stdc_store8_aligned_bes16
stdc_store8_aligned_bes32stdc_store8_aligned_bes32
stdc_store8_aligned_bes64stdc_store8_aligned_bes64
stdc_store8_aligned_bes8stdc_store8_aligned_bes8
stdc_store8_aligned_beu16stdc_store8_aligned_beu16
stdc_store8_aligned_beu32stdc_store8_aligned_beu32
stdc_store8_aligned_beu64stdc_store8_aligned_beu64
stdc_store8_aligned_beu8stdc_store8_aligned_beu8
stdc_store8_aligned_les16stdc_store8_aligned_les16
stdc_store8_aligned_les32stdc_store8_aligned_les32
stdc_store8_aligned_les64stdc_store8_aligned_les64
stdc_store8_aligned_les8stdc_store8_aligned_les8
stdc_store8_aligned_leu16stdc_store8_aligned_leu16
stdc_store8_aligned_leu32stdc_store8_aligned_leu32
stdc_store8_aligned_leu64stdc_store8_aligned_leu64
stdc_store8_aligned_leu8stdc_store8_aligned_leu8
stdc_store8_bes16stdc_store8_bes16
stdc_store8_bes32stdc_store8_bes32
stdc_store8_bes64stdc_store8_bes64
stdc_store8_bes8stdc_store8_bes8
stdc_store8_beu16stdc_store8_beu16
stdc_store8_beu32stdc_store8_beu32
stdc_store8_beu64stdc_store8_beu64
stdc_store8_beu8stdc_store8_beu8
stdc_store8_les16stdc_store8_les16
stdc_store8_les32stdc_store8_les32
stdc_store8_les64stdc_store8_les64
stdc_store8_les8stdc_store8_les8
stdc_store8_leu16stdc_store8_leu16
stdc_store8_leu32stdc_store8_leu32
stdc_store8_leu64stdc_store8_leu64
stdc_store8_leu8stdc_store8_leu8
stdc_trailing_onesstdc_trailing_ones
stdc_trailing_zerosstdc_trailing_zeros
stderrstderr
stdinstdin
stdopenClosed standard fds
stdoutstdout
stepstep
stimestime
STP_BLKSIZEstat-size
STP_NBLOCKSstat-size
stpcpystpcpy
stpncpystpncpy
str2sigstr2sig
strcasecmpstrcasecmp
strcasecmp_lstrcasecmp_l
strcasestrstrcasestr
strcatstrcat
strchrstrchr
strchrnulstrchrnul
strcmpstrcmp
strcollstrcoll
strcoll_lstrcoll_l
strcpystrcpy
strcspnstrcspn
strdupstrdup
strerrorstrerror
strerror_lstrerror_l
strerror_rstrerror_r
strerrordesc_npstrerrordesc_np
strerrorname_npstrerrorname_np
strfmonstrfmon
strfmon_lstrfmon_l
strfromdstrfromd
strfromfstrfromf
strfromlstrfroml
strfrystrfry
strftimestrftime
strftime_lstrftime_l
strlcatstrlcat
strlcpystrlcpy
strlenstrlen
strncasecmpstrncasecmp
strncasecmp_lstrncasecmp_l
strncatstrncat
strncmpstrncmp
strncpystrncpy
strndupstrndup
strnlenstrnlen
strpbrkstrpbrk
strptimestrptime
strptime_lstrptime_l
strrchrstrrchr
strsepstrsep
strsignalstrsignal
strspnstrspn
strstrstrstr
strtodstrtod
strtod_lstrtod_l
strtofstrtof
strtof_lstrtof_l
strtoimaxstrtoimax
strtokstrtok
strtok_rstrtok_r
strtolstrtol
strtol_lstrtol_l
strtoldstrtold
strtold_lstrtold_l
strtollstrtoll
strtoll_lstrtoll_l
strtoqstrtoq
strtoulstrtoul
strtoul_lstrtoul_l
strtoullstrtoull
strtoull_lstrtoull_l
strtoumaxstrtoumax
strtouqstrtouq
struct re_pattern_buffer definitionGNU Pattern Buffers
strverscmpstrverscmp
strxfrmstrxfrm
strxfrm_lstrxfrm_l
subexpressionsGrouping Operators
supply chain attacksOther source code libraries
svc_exitsvc_exit
svc_fdsetsvc_fdset
svc_getreqsvc_getreq
svc_getreq_commonsvc_getreq_common
svc_getreq_pollsvc_getreq_poll
svc_getreqsetsvc_getreqset
svc_max_pollfdsvc_max_pollfd
svc_pollfdsvc_pollfd
svc_registersvc_register
svc_runsvc_run
svc_sendreplysvc_sendreply
svc_unregistersvc_unregister
svcerr_authsvcerr_auth
svcerr_decodesvcerr_decode
svcerr_noprocsvcerr_noproc
svcerr_noprogsvcerr_noprog
svcerr_progverssvcerr_progvers
svcerr_systemerrsvcerr_systemerr
svcerr_weakauthsvcerr_weakauth
svcraw_createsvcraw_create
svctcp_createsvctcp_create
svcudp_bufcreatesvcudp_bufcreate
svcudp_createsvcudp_create
svcunix_createsvcunix_create
swabswab
swapcontextswapcontext
swapoffswapoff
swaponswapon
swprintfswprintf
swscanfswscanf
symlinksymlink
symlinkatsymlinkat
syncsync
sync_file_rangesync_file_range
syncfssyncfs
syntax bitsSyntax Bits
syntax field, set by re_compile_patternGNU Regular Expression Compiling
syntax initializationGNU Regular Expression Compiling
syntax of regular expressionsRegular Expression Syntax
sys_errlistsys_errlist
sys_nerrsys_nerr
sys_siglistsys_siglist
syscallsyscall
sysconfsysconf
sysctlsysctl
sysinfosysinfo
syslogsyslog
systemsystem
sysv_signalsysv_signal
T
tantan
tanftanf
tanhtanh
tanhftanhf
tanhltanhl
tanltanl
tanpitanpi
tanpiftanpif
tanpiltanpil
tcdraintcdrain
tcflowtcflow
tcflushtcflush
tcgetattrtcgetattr
tcgetpgrptcgetpgrp
tcgetsidtcgetsid
tcgetwinsizetcgetwinsize
tcsendbreaktcsendbreak
tcsetattrtcsetattr
tcsetpgrptcsetpgrp
tcsetwinsizetcsetwinsize
tdeletetdelete
tdestroytdestroy
telldirtelldir
tempnamtempnam
tests modules, C++Extra tests modules
tests modules, long-runningExtra tests modules
tests modules, privilegedExtra tests modules
tests modules, unportableExtra tests modules
textdomaintextdomain
tfindtfind
tgammatgamma
tgammaftgammaf
tgammaltgammal
tgkilltgkill
thrd_createthrd_create
thrd_currentthrd_current
thrd_detachthrd_detach
thrd_equalthrd_equal
thrd_exitthrd_exit
thrd_jointhrd_join
thrd_sleepthrd_sleep
thrd_yieldthrd_yield
timetime
timegmtimegm
timelocaltimelocal
timer_createtimer_create
timer_deletetimer_delete
timer_getoverruntimer_getoverrun
timer_gettimetimer_gettime
timer_settimetimer_settime
timerfd_createtimerfd_create
timerfd_gettimetimerfd_gettime
timerfd_settimetimerfd_settime
timestimes
timespec_gettimespec_get
timespec_getrestimespec_getres
timezonetimezone
tmpfiletmpfile
tmpnamtmpnam
tmpnam_rtmpnam_r
toasciitoascii
tolowertolower
tolower_ltolower_l
totalordertotalorder
totalorderftotalorderf
totalorderltotalorderl
totalordermagtotalordermag
totalordermagftotalordermagf
totalordermagltotalordermagl
touppertoupper
toupper_ltoupper_l
towctranstowctrans
towctrans_ltowctrans_l
towlowertowlower
towlower_ltowlower_l
towuppertowupper
towupper_ltowupper_l
translate initializationGNU Regular Expression Compiling
trunctrunc
truncatetruncate
truncftruncf
truncltruncl
tsearchtsearch
tss_createtss_create
tss_deletetss_delete
tss_gettss_get
tss_settss_set
ttynamettyname
ttyname_rttyname_r
ttyslotttyslot
twalktwalk
twalk_rtwalk_r
type conversion, arithmeticArithmetic Type Conversion
TYPE_IS_INTEGERArithmetic Type Properties
TYPE_MAXIMUMInteger Bounds
TYPE_MINIMUMInteger Bounds
TYPE_SIGNEDArithmetic Type Properties
tznametzname
tzsettzset
U
uabsuabs
ualarmualarm
ufromfpufromfp
ufromfpfufromfpf
ufromfplufromfpl
ufromfpxufromfpx
ufromfpxfufromfpxf
ufromfpxlufromfpxl
ulabsulabs
ulckpwdfulckpwdf
ulimitulimit
ullabsullabs
umaskumask
umaxabsumaxabs
umountumount
umount2umount2
unameuname
ungetcungetc
ungetwcungetwc
unibyte localeC strings
unlinkunlink
unlinkatunlinkat
unlockptunlockpt
unportable tests modulesExtra tests modules
unsetenvunsetenv
updwtmpupdwtmp
updwtmpxupdwtmpx
uselocaleuselocale
user2netnameuser2netname
usleepusleep
ustatustat
utimeutime
utimensatutimensat
utimesutimes
utmpnameutmpname
utmpxnameutmpxname
V
va_argva_arg
va_copyva_copy
va_endva_end
va_startva_start
valgrindRunning self-tests under valgrind
vallocvalloc
vasprintfvasprintf
VCS To ChangeLogVCS To ChangeLog
vdprintfvdprintf
verifyCompile-time Assertions
verify_exprCompile-time Assertions
verrverr
verrxverrx
versionsortversionsort
vforkvfork
vfprintfvfprintf
vfscanfvfscanf
vfwprintfvfwprintf
vfwscanfvfwscanf
vhangupvhangup
vlimitvlimit
voidSafe Allocation Macros
vprintfvprintf
vscanfvscanf
vsnprintfvsnprintf
vsprintfvsprintf
vsscanfvsscanf
vswprintfvswprintf
vswscanfvswscanf
vsyslogvsyslog
vwarnvwarn
vwarnxvwarnx
vwprintfvwprintf
vwscanfvwscanf
W
waitwait
wait3wait3
wait4wait4
waitidwaitid
waitpidwaitpid
warnwarn
warnxwarnx
wcpcpywcpcpy
wcpncpywcpncpy
wcrtombwcrtomb
wcscasecmpwcscasecmp
wcscasecmp_lwcscasecmp_l
wcscatwcscat
wcschrwcschr
wcschrnulwcschrnul
wcscmpwcscmp
wcscollwcscoll
wcscoll_lwcscoll_l
wcscpywcscpy
wcscspnwcscspn
wcsdupwcsdup
wcsftimewcsftime
wcsftime_lwcsftime_l
wcslcatwcslcat
wcslcpywcslcpy
wcslenwcslen
wcsncasecmpwcsncasecmp
wcsncasecmp_lwcsncasecmp_l
wcsncatwcsncat
wcsncmpwcsncmp
wcsncpywcsncpy
wcsnlenwcsnlen
wcsnrtombswcsnrtombs
wcspbrkwcspbrk
wcsrchrwcsrchr
wcsrtombswcsrtombs
wcsspnwcsspn
wcsstrwcsstr
wcstodwcstod
wcstod_lwcstod_l
wcstofwcstof
wcstof_lwcstof_l
wcstoimaxwcstoimax
wcstokwcstok
wcstolwcstol
wcstol_lwcstol_l
wcstoldwcstold
wcstold_lwcstold_l
wcstollwcstoll
wcstoll_lwcstoll_l
wcstombswcstombs
wcstoqwcstoq
wcstoulwcstoul
wcstoul_lwcstoul_l
wcstoullwcstoull
wcstoull_lwcstoull_l
wcstoumaxwcstoumax
wcstouqwcstouq
wcswcswcswcs
wcswidthwcswidth
wcsxfrmwcsxfrm
wcsxfrm_lwcsxfrm_l
wctobwctob
wctombwctomb
wctranswctrans
wctrans_lwctrans_l
wctypewctype
wctype_lwctype_l
wcwidthwcwidth
wmemchrwmemchr
wmemcmpwmemcmp
wmemcpywmemcpy
wmemmovewmemmove
wmempcpywmempcpy
wmemsetwmemset
word boundaries, matchingMatch-word-boundary Operator
wordexpwordexp
wordfreewordfree
wprintfwprintf
wraparound integer arithmeticWraparound Arithmetic
writewrite
writevwritev
wscanfwscanf
X
xalloc_dieOut of memory handling
xdr_arrayxdr_array
xdr_authunix_parmsxdr_authunix_parms
xdr_boolxdr_bool
xdr_bytesxdr_bytes
xdr_callhdrxdr_callhdr
xdr_callmsgxdr_callmsg
xdr_cback_dataxdr_cback_data
xdr_charxdr_char
xdr_cryptkeyargxdr_cryptkeyarg
xdr_cryptkeyarg2xdr_cryptkeyarg2
xdr_cryptkeyresxdr_cryptkeyres
xdr_des_blockxdr_des_block
xdr_domainnamexdr_domainname
xdr_doublexdr_double
xdr_enumxdr_enum
xdr_floatxdr_float
xdr_freexdr_free
xdr_getcredresxdr_getcredres
xdr_hyperxdr_hyper
xdr_intxdr_int
xdr_int16_txdr_int16_t
xdr_int32_txdr_int32_t
xdr_int64_txdr_int64_t
xdr_int8_txdr_int8_t
xdr_key_netstargxdr_key_netstarg
xdr_key_netstresxdr_key_netstres
xdr_keybufxdr_keybuf
xdr_keydatxdr_keydat
xdr_keystatusxdr_keystatus
xdr_longxdr_long
xdr_longlong_txdr_longlong_t
xdr_netnamestrxdr_netnamestr
xdr_netobjxdr_netobj
xdr_obj_pxdr_obj_p
xdr_opaquexdr_opaque
xdr_opaque_authxdr_opaque_auth
xdr_pmapxdr_pmap
xdr_pmaplistxdr_pmaplist
xdr_pointerxdr_pointer
xdr_quad_txdr_quad_t
xdr_referencexdr_reference
xdr_replymsgxdr_replymsg
xdr_rmtcall_argsxdr_rmtcall_args
xdr_rmtcallresxdr_rmtcallres
xdr_shortxdr_short
xdr_sizeofxdr_sizeof
xdr_stringxdr_string
xdr_u_charxdr_u_char
xdr_u_hyperxdr_u_hyper
xdr_u_intxdr_u_int
xdr_u_longxdr_u_long
xdr_u_longlong_txdr_u_longlong_t
xdr_u_quad_txdr_u_quad_t
xdr_u_shortxdr_u_short
xdr_uint16_txdr_uint16_t
xdr_uint32_txdr_uint32_t
xdr_uint64_txdr_uint64_t
xdr_uint8_txdr_uint8_t
xdr_unionxdr_union
xdr_unixcredxdr_unixcred
xdr_valdatxdr_valdat
xdr_vectorxdr_vector
xdr_voidxdr_void
xdr_wrapstringxdr_wrapstring
xdr_ypbind_resptypexdr_ypbind_resptype
xdr_ypmap_parmsxdr_ypmap_parms
xdr_ypmaplistxdr_ypmaplist
xdr_yppushresp_xfrxdr_yppushresp_xfr
xdr_ypreq_keyxdr_ypreq_key
xdr_ypreq_nokeyxdr_ypreq_nokey
xdr_ypreq_xfrxdr_ypreq_xfr
xdr_ypresp_allxdr_ypresp_all
xdr_ypresp_key_valxdr_ypresp_key_val
xdr_ypresp_maplistxdr_ypresp_maplist
xdr_ypresp_masterxdr_ypresp_master
xdr_ypresp_orderxdr_ypresp_order
xdr_ypresp_valxdr_ypresp_val
xdr_ypresp_xfrxdr_ypresp_xfr
xdr_ypstatxdr_ypstat
xdr_ypxfrstatxdr_ypxfrstat
xdrmem_createxdrmem_create
xdrrec_createxdrrec_create
xdrrec_endofrecordxdrrec_endofrecord
xdrrec_eofxdrrec_eof
xdrrec_skiprecordxdrrec_skiprecord
xdrstdio_createxdrstdio_create
xprt_registerxprt_register
xprt_unregisterxprt_unregister
Y
y0y0
y0fy0f
y0ly0l
y1y1
y1fy1f
y1ly1l
ynyn
ynfynf
ynlynl
yp_allyp_all
yp_bindyp_bind
yp_firstyp_first
yp_get_default_domainyp_get_default_domain
yp_masteryp_master
yp_matchyp_match
yp_nextyp_next
yp_orderyp_order
yp_unbindyp_unbind
ypbinderr_stringypbinderr_string
yperr_stringyperr_string
ypprot_errypprot_err
Jump to:   _   -   ?   .   (   )   [   ]   {   }   *   \   ^   +   =   |   $  
A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y  

Footnotes

(1)

Ristenpart T, Yilek S. When good randomness goes bad: virtual machine vulnerabilities and hedging deployed cryptography. NDSS 2010.

(2)

Ristenpart T, Yilek S. When good randomness goes bad: virtual machine vulnerabilities and hedging deployed cryptography. NDSS 2010.

(3)

Sometimes you don’t have to explicitly quote special characters to make them ordinary. For instance, most characters lose any special meaning inside a list (see List Operators ([ … ] and [^ … ])). In addition, if the syntax bits RE_CONTEXT_INVALID_OPS and RE_CONTEXT_INDEP_OPS aren’t set, then (for historical reasons) the matcher considers special characters ordinary if they are in contexts where the operations they represent make no sense; for example, then the match-zero-or-more operator (represented by ‘*’) matches itself in the regular expression ‘*foo’ because there is no preceding expression on which it can operate. It is poor practice, however, to depend on this behavior; if you want a special character to be ordinary outside a list, it’s better to always quote it, regardless.

(4)

Regex therefore doesn’t consider the ‘^’ to be the first character in the list. If you put a ‘^’ character first in (what you think is) a matching list, you’ll turn it into a nonmatching list.

(5)

You can’t use a character class for the starting or ending point of a range, since a character class is not a single character.

(6)

Regular expressions are also referred to as “patterns,” hence the name “pattern buffer.”

(7)

A table that maps all uppercase letters to the corresponding lowercase ones would work just as well for this purpose.