@node pthread_sigmask @section @code{pthread_sigmask} @findex pthread_sigmask POSIX specification:@* @url{https://pubs.opengroup.org/onlinepubs/9699919799/functions/pthread_sigmask.html} Gnulib module: pthread_sigmask Portability problems fixed by Gnulib: @itemize @item This function is missing on some platforms: Minix 3.1.8, mingw, MSVC 14. @item This function is declared in @code{} instead of @code{} on some platforms: FreeBSD 6.4, OpenBSD 3.8. @item This function does nothing and always returns 0 in programs that are not linked with @code{-lpthread} on some platforms: FreeBSD 13.0, MidnightBSD 1.1, HP-UX 11.31, Solaris 9. @item When it fails, this functions returns @minus{}1 instead of the error number on some platforms: Cygwin 1.7.5. @item This function does not immediately raise signals that were pending before the call and unblocked by the call on some platforms: IRIX 6.5. @end itemize Portability problems not fixed by Gnulib: @itemize @item On platforms that do not natively support this function, it has unspecified behavior in a multi-threaded process. @item In case of failure, the return value is wrong on some platforms: NetBSD 9.0 when libpthread is not in use. @end itemize