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alarm(2)			 System	Calls			      alarm(2)

NAME
       alarm - schedule	an alarm signal

SYNOPSIS
       #include	<unistd.h>

       unsigned	int alarm(unsigned int sec);

DESCRIPTION
       The alarm() function causes the system to generate a SIGALRM signal for
       the process after the number of real-time seconds specified by  seconds
       have   elapsed  (see  signal.h(3HEAD)). Processor scheduling delays may
       prevent the process from	handling the signal as soon as	it  is	gener-
       ated.

       If seconds is 0,	a pending alarm	request, if any, is cancelled.

       Alarm  requests	are  not stacked; only one SIGALRM  generation can  be
       scheduled in this manner; if the	SIGALRM	signal has not yet been	gener-
       ated,  the  call	 will  result  in  rescheduling	 the time at which the
       SIGALRM signal will be generated.

       The fork(2) function clears pending alarms in the child process.	A  new
       process	image  created	by one of the exec functions inherits the time
       left to an alarm	signal in the old process's image.

RETURN VALUES
       If there	is a previous alarm  request  with  time   remaining,  alarm()
       returns	 a   non-zero  value  that  is the number of seconds until the
       previous	request	would  have  generated	a SIGALRM signal.   Otherwise,
       alarm() returns 0.

ERRORS
       The  alarm() function is	always successful; no return value is reserved
       to indicate an error.

ATTRIBUTES
       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE	TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |Async-Signal-Safe		   |
       +-----------------------------+-----------------------------+

SEE ALSO
       exec(2),	fork(2), signal.h(3HEAD), attributes(5), standards(5)

SunOS 5.10			  7 Jun	2001			      alarm(2)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUES | ERRORS | ATTRIBUTES | SEE ALSO

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