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ALARM(3)	       FreeBSD Library Functions Manual		      ALARM(3)

NAME
     alarm -- set signal timer alarm

LIBRARY
     Standard C	Library	(libc, -lc)

SYNOPSIS
     #include <unistd.h>

     unsigned int
     alarm(unsigned int	seconds);

DESCRIPTION
     This interface is made obsolete by	setitimer(2).

     The alarm() function sets a timer to deliver the signal SIGALRM to	the
     calling process after the specified number	of seconds.  If	an alarm has
     already been set with alarm() but has not been delivered, another call to
     alarm() will supersede the	prior call.  The request alarm(0) voids	the
     current alarm and the signal SIGALRM will not be delivered.

     Due to setitimer(2) restriction the maximum number	of seconds allowed is
     100000000.

RETURN VALUES
     The return	value of alarm() is the	amount of time left on the timer from
     a previous	call to	alarm().  If no	alarm is currently set,	the return
     value is 0.

SEE ALSO
     setitimer(2), sigaction(2), sigsuspend(2),	signal(3), sleep(3),
     ualarm(3),	usleep(3)

HISTORY
     An	alarm()	function appeared in Version 7 AT&T UNIX.

FreeBSD	10.1			April 19, 1994			  FreeBSD 10.1

NAME | LIBRARY | SYNOPSIS | DESCRIPTION | RETURN VALUES | SEE ALSO | HISTORY

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