SIGWAIT(2) BSD System Calls Manual SIGWAIT(2)
sigwait -- select a set of signals
sigwait(const sigset_t *set, int *sig);
The sigwait() function selects a set of signals, specified by set. If
none of the selected signals are pending, sigwait() waits until one or
more of the selected signals has been generated. Then sigwait() atomi-
cally clears one of the selected signals from the set of pending signals
for the process and sets the location pointed to by sig to the signal
number that was cleared.
The signals specified by set should be blocked, but not ignored, at the
time of the call to sigwait().
Processes which call sigwait() on ignored signals will wait indefinately.
Ignored signals are dropped immeadiately by the system, before delivery
to a waiting process.
If successful, sigwait() returns 0 and sets the location pointed to by
sig to the cleared signal number. Otherwise, an error number is
sigwait() will fail if:
[EINVAL] set specifies one or more invalid signal numbers.
sigaction(2), sigpending(2), sigsuspend(2), pause(3), pthread_sigmask(2)
sigwait() conforms to ISO/IEC 9945-1:1996 (``POSIX.1'')
BSD April 27, 2000 BSD