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SIGSUSPEND(2)               BSD System Calls Manual              SIGSUSPEND(2)

     sigsuspend -- atomically release blocked signals and wait for interrupt

     #include <signal.h>

     sigsuspend(const sigset_t *sigmask);

     Sigsuspend() temporarily changes the blocked signal mask to the set to which sigmask points, and then
     waits for a signal to arrive; on return the previous set of masked signals is restored.  The signal
     mask set is usually empty to indicate that all signals are to be unblocked for the duration of the

     In normal usage, a signal is blocked using sigprocmask(2) to begin a critical section, variables modi-fied modified
     fied on the occurrence of the signal are examined to determine that there is no work to be done, and
     the process pauses awaiting work by using sigsuspend() with the previous mask returned by sigprocmask.

     The sigsuspend() function always terminates by being interrupted, returning -1 with errno set to EINTR.

     sigaction(2), sigprocmask(2), sigsetops(3)

     The sigsuspend function call conforms to IEEE Std 1003.1-1988 (``POSIX.1'').

BSD                              June 4, 1993                              BSD

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