ALARM(3) OpenBSD Programmer's Manual ALARM(3)NAMEalarm - set signal timer alarmSYNOPSIS
alarm(unsigned int seconds);
This interface is made obsolete by setitimer(2).
The alarm() function waits a count of seconds before asserting the
terminating signal SIGALRM. When the signal has successfully been
caught, alarm() returns the amount of time left on the clock. The
maximum number of seconds allowed is 100000000.
If an alarm has been set with alarm(), another call to alarm() will
supersede the prior call. The request alarm(0) voids the current alarm.
If the call succeeds, any time left remaining from a previous call is
returned. If an error occurs, the value -1 is returned, and a more
precise error code is placed in the global variable errno.
SEE ALSOsetitimer(2), sigaction(2), signal(3), sigpause(3), sigvec(3), sleep(3),
The alarm() function conforms to IEEE Std 1003.1-1990 (``POSIX'').
An alarm() function appeared in Version 7 AT&T UNIX.
OpenBSD 4.9 May 31, 2007 OpenBSD 4.9