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usleep(2)		      System Calls Manual		     usleep(2)

NAME
       usleep -	suspend	execution for an interval

SYNOPSIS
DESCRIPTION
       The  function will cause	the calling thread to be suspended from	execu-
       tion until either the number of real-time microseconds specified	by the
       argument	 useconds has elapsed, or a signal is delivered	to the calling
       thread and its action is	to invoke a  signal-catching  function	or  to
       terminate the process.

       The  suspension time may	be longer than requested due to	the scheduling
       of other	activities by the system, or because of	the time spent in pro-
       cessing the call.

       The  useconds  argument	must  be less than 1,000,000.  If the value of
       useconds	is 0, then the call has	no effect.

       If a signal is generated	for the	calling	process	 during	 execution  of
       and  if the signal is being ignored or blocked from delivery, it	is un-
       specified whether returns when the signal is scheduled; if  the	signal
       is being	blocked, it is also unspecified	whether	it remains pending af-
       ter returns or it is discarded.

       If a signal is generated	for the	calling	process	 during	 execution  of
       except  as  a  result of	a prior	call to	and if the signal is not being
       ignored or blocked from delivery, it is unspecified whether that	signal
       has any effect other than causing to return.

       If a signal-catching function interrupts	and examines or	changes	either
       the time	a is scheduled to be generated,	the action associated with the
       signal, or whether the signal is	blocked	from delivery, the results are
       unspecified.

       If a signal-catching function interrupts	and calls or to	restore	an en-
       vironment  saved	prior to the call, the action associated with the sig-
       nal and the time	at which a signal is scheduled to be generated are un-
       specified, it is	also unspecified whether the signal is blocked,	unless
       the process's signal mask is restored as	part of	the environment.

       Implementations may place limitations on	the granularity	of timer  val-
       ues.  For  each interval	timer, if the requested	timer value requires a
       finer granularity than the implementation supports,  the	 actual	 timer
       value will be rounded up	to the next supported value.

       Interactions between and	any of the following are unspecified:

RETURN VALUE
       On  successful completion, returns 0. Otherwise,	it returns -1 and sets
       to indicate the error.

ERRORS
       The function may	fail if:

	      [EINVAL]		       The time	interval  specified  1,000,000
				       or more microseconds.

APPLICATION USAGE
       The function is included	for its	historical usage. The function is pre-
       ferred over this	function. Multi-threaded applications are  recommended
       to use instead of is also a thread canceling point.

SEE ALSO
       alarm(2),    getitimer(2),   nanosleep(2),   sigaction(2),   sleep(3C),
       timer_create(2),	  timer_delete(2),   timer_getoverrun(2),   timer_get-
       time(2),	timer_settime(2), <unistd.h>.

CHANGE HISTORY
       First released in Issue 4, Version 2.

								     usleep(2)

NAME | SYNOPSIS | DESCRIPTION | RETURN VALUE | ERRORS | APPLICATION USAGE | SEE ALSO | CHANGE HISTORY

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