Can Unix sleep in terms of mili/micro?

[Walter Rowe]

To quote a SunOS man page:
======================================================================
NAME
     usleep - suspend execution for interval in microseconds

SYNOPSIS
     usleep(useconds)
     unsigned useconds;

DESCRIPTION
     Suspend the current process for the number  of  microseconds
     specified  by  the argument.  The actual suspension time may
     be an arbitrary amount longer because of other  activity  in
     the  system,  or because of the time spent in processing the
     call.

     The routine is implemented by setting an interval timer  and
     pausing  until  it occurs.  The previous state of this timer
     is saved and restored.  If the sleep time exceeds  the  time
     to  the expiration of the previous timer, the process sleeps
     only until the signal would have occurred, and the signal is
     sent a short time later.

     This routine is implemented using setitimer()  (see  getiti-
     mer(2));  it  requires  eight  system  calls each time it is
     invoked.  A similar but  less  compatible  function  can  be
     obtained with a single select(2); it would not restart after
     signals, but would not interfere with other uses of  setiti-
     mer.

SEE ALSO
     getitimer(2), sigpause(2V), alarm(3V), sleep(3V), ualarm(3)
======================================================================

wpr
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Walter P. Rowe                                    ARPA: rowe at cme.nist.gov
System Administrator, Robot Systems Division      UUCP: uunet!cme-durer!rowe
National Institute of Standards and Technology    LIVE: (301) 975-3694