sleep(3C)                                               sleep(3C)



NAME
     sleep - suspends execution for interval

SYNOPSIS
     unsigned sleep(seconds)
     unsigned seconds;

DESCRIPTION
     sleep suspends the current process from execution for the
     number of seconds specified by the argument.  The actual
     suspension time may be less than that requested for two
     reasons: (1) scheduled wakeups occur at fixed 1-second
     intervals, (on the second, according to an internal clock),
     and (2) any caught signal will terminate sleep following
     execution of the signal catching routine.  The suspension
     time may be longer than requested by an arbitrary amount,
     due to the scheduling of other activity in the system.  The
     value returned by sleep is the ``unslept'' amount (the
     requested time minus the time actually slept) in case the
     caller had an alarm set to go off earlier than the end of
     the requested sleep time or in case there is premature
     arousal due to another caught signal.

     The routine is implemented by setting an alarm signal and
     pausing until it (or some other signal) occurs.  The
     previous state of the alarm signal is saved and restored.
     The calling program may have set up an alarm signal before
     calling sleep.  If the sleep time exceeds the time before
     the alarm signal, the process sleeps only until the alarm
     signal would have occurred and the caller's alarm catch
     routine is executed just before the sleep routine returns.
     If the sleep time is less than the time before the calling
     program's alarm, the prior alarm time is reset to go off at
     the same time it would have without the intervening sleep.

SEE ALSO
     alarm(2), pause(2), signal(3)


















January 1992                                                    1