---

9.56 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 2.40.

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.