usleep(3)                           CLIX                           usleep(3)



  NAME

    usleep - Suspends execution for an interval of time

  LIBRARY

    Berkeley Software Distribution (libbsd.a)

  SYNOPSIS

    void usleep(
      unsigned useconds );

  PARAMETERS

    useconds   Specifies the number of microseconds to suspend the execution
               of the current process.

  DESCRIPTION

    The usleep() function suspends the current process from execution for the
    number of microseconds specified by useconds.  The actual suspension time
    may be longer due to other system activity or the time spent in processing
    the call.

    This function is implemented by setting an interval timer and pausing
    until the timer expires.  The previous state of this timer is saved and
    restored.  If the interval timer is set more than once and the new sleep
    time exceeds the time until the expiration of a previous timer, the
    process sleeps only until the signal would have occurred.  The signal is
    sent a short time later.

    The usleep() function uses setitimer() to set the interval timer.  A
    similar but less compatible function can be obtained with a single
    select(); it would not restart after signals, but would not interfere with
    other uses of setitimer().

  RELATED INFORMATION

    Functions:  setitimer(2), getitimer(2), sigset(2), sleep(3), alarm(3)














  2/94 - Intergraph Corporation                                              1