NAME

       sigwait - wait for a signal

SYNOPSIS

       #include <signal.h>

        int sigwait(const sigset_t *set, int *sig);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       sigwait():
           Since glibc 2.26:
               _POSIX_C_SOURCE >= 199506L
           Glibc 2.25 and earlier:
               _POSIX_C_SOURCE

DESCRIPTION

       The sigwait() function suspends execution of the calling thread until one of the signals specified in the
       signal  set  set  becomes  pending.  The function accepts the signal (removes it from the pending list of
       signals), and returns the signal number in sig.

       The operation of sigwait() is the same as sigwaitinfo(2), except that:

       * sigwait() returns only the signal number, rather than a siginfo_t structure describing the signal.

       * The return values of the two functions are different.

RETURN VALUE

       On success, sigwait() returns 0.  On error, it returns a positive error number (listed in ERRORS).

ERRORS

       EINVAL set contains an invalid signal number.

ATTRIBUTES

       For an explanation of the terms used in this section, see attributes(7).
       ┌───────────┬───────────────┬─────────┐
       │ Interface │ Attribute     │ Value   │
       ├───────────┼───────────────┼─────────┤
       │ sigwait() │ Thread safety │ MT-Safe │
       └───────────┴───────────────┴─────────┘

CONFORMING TO

       POSIX.1-2001, POSIX.1-2008.

NOTES

       sigwait() is implemented using sigtimedwait(2).

       The glibc implementation of sigwait() silently ignores attempts to wait for  the  two  real-time  signals
       that are used internally by the NPTL threading implementation.  See nptl(7) for details.

EXAMPLES

       See pthread_sigmask(3).

SEE ALSO

       sigaction(2), signalfd(2), sigpending(2), sigsuspend(2), sigwaitinfo(2), sigsetops(3), signal(7)

COLOPHON

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       information  about  reporting  bugs,  and  the  latest  version  of  this   page,   can   be   found   at
       https://www.kernel.org/doc/man-pages/.

Linux                                              2020-06-09                                         SIGWAIT(3)