@node sigprocmask
@section @code{sigprocmask}
@findex sigprocmask

POSIX specification:@* @url{https://pubs.opengroup.org/onlinepubs/9699919799/functions/sigprocmask.html}

Gnulib module: sigprocmask

Portability problems fixed by Gnulib:
@itemize
@item
This function is missing on some platforms:
mingw, MSVC 14.
@end itemize

Portability problems not fixed by Gnulib:
@itemize
@item
In case of failure, the return value is wrong on some platforms:
NetBSD 9.0 when libpthread is in use.
@end itemize

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