USLEEP(P)           Linux Programmer's Manual           USLEEP(P)



NAME
       usleep - suspend execution for microsecond intervals

SYNOPSIS
       #include <unistd.h>

       void usleep(unsigned long usec);
       int usleep(unsigned long usec); /* SUSv2 */

DESCRIPTION
       The  usleep()  function  suspends execution of the calling
       process for usec microseconds.  The sleep may  be  length-
       ened  slightly by any system activity or by the time spent
       processing the call.

RETURN VALUE
       None (BSD). Or: 0 on success, -1 on error (SUSv2).

ERRORS
       EINTR  Interrupted by a signal.

       EINVAL usec is not  smaller  than  1000000.   (On  systems
              where that is considered an error.)

CONFORMING TO
       BSD  4.3.  The SUSv2 version returns int, and this is also
       the prototype used by glibc 2.2.2.  Only the EINVAL  error
       return is documented by SUSv2.

NOTES
       The  interaction  of  this function with SIGALRM and other
       timer functions such  as  sleep(),  alarm(),  setitimer(),
       nanosleep()  is  unspecified.   This function is obsolete.
       Use nanosleep(p) or setitimer(r) instead.

SEE ALSO
       alarm(m),    getitimer(r),    nanosleep(p),     select(t),
       setitimer(r), sleep(p)



                            2001-04-02                  USLEEP(P)