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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.

Note: Although sigprocmask officially has undefined behaviour in multi-threaded programs, in practice it is essentially equivalent to pthread_sigmask, with only a difference regarding the error return convention. It’s simpler to use sigprocmask, since it does not require linking with -lpthread on some platforms: glibc, NetBSD, OpenBSD, AIX.

Note: While on POSIX platforms, sigprocmask is multithread-safe and async-signal safe (cf. POSIX section “Signal Actions” https://pubs.opengroup.org/onlinepubs/9799919799/functions/V2_chap02.html#tag_16_04_03), the gnulib replacement on native Windows is only multithread-safe, not async-signal safe.