sleep(3C)                                               sleep(3C)



     NAME
          sleep - suspend 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).


















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