NAME

     sigsuspend — atomically release blocked signals and wait for interrupt

LIBRARY

     Standard C Library (libc, -lc)

SYNOPSIS

     #include <signal.h>

     int
     sigsuspend(const sigset_t *sigmask);

DESCRIPTION

     The sigsuspend() system call 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 call.

     In normal usage, a signal is blocked using sigprocmask(2) to begin a critical section,
     variables modified 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(2).

RETURN VALUES

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

SEE ALSO

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

STANDARDS

     The sigsuspend() system call is expected to conform to ISO/IEC 9945-1:1990 (“POSIX.1”).