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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 7.5, 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.