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alarm(2)		      System Calls Manual		      alarm(2)

NAME
       alarm - set a process's alarm clock

SYNOPSIS
DESCRIPTION
       instructs  the  alarm  clock  of	the calling process to send the	signal
       SIGALRM to the calling process after the	number	of  real-time  seconds
       specified by sec	have elapsed; see signal(5).  Specific implementations
       might place limitations on the maximum supported	alarm time.  The  con-
       stant  MAX_ALARM	defined	in specifies the implementation-specific maxi-
       mum.  Whenever sec is greater that this maximum,	it is silently rounded
       down  to	 it.   On all implementations, is guaranteed to	be at least 31
       days (in	seconds).

       Alarm requests are not stacked; successive calls	reset the alarm	 clock
       of the calling process.

       If sec is 0, any	previously made	alarm request is canceled.

       Alarms  are not inherited by a child process across a but are inherited
       across an

       On systems that support the and system calls, the timer mechanism  used
       by  is  the same	as that	used by	ITIMER_REAL.  Thus successive calls to
       and set and return the state of a single	timer.	In addition, sets  the
       timer interval to zero.

RETURN VALUE
       returns	the  amount of time previously remaining in the	alarm clock of
       the calling process.

WARNINGS
       In some implementations,	error bounds for alarm are -1, +0 seconds (for
       the  posting of the alarm, not the restart of the process).  Thus a de-
       lay of 1	second can return immediately.	The routine  can  be  used  to
       create a	more precise delay.

SEE ALSO
       sleep(1), exec(2), getitimer(2),	pause(2), signal(5), sleep(3C).

STANDARDS CONFORMANCE
								      alarm(2)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | WARNINGS | SEE ALSO | STANDARDS CONFORMANCE

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