SLEEP(3)                  386BSD Programmer's Manual                  SLEEP(3)

NAME
     sleep - suspend process execution for interval of seconds

SYNOPSIS
     #include <unistd.h>

     int
     sleep(u_int seconds)

DESCRIPTION
     The sleep() function suspends execution of the calling process for
     seconds of time.  System activity or time spent in processing the call
     may lengthen the sleep by a second.

     If a timer is already running on the process its state is saved.  If the
     value seconds is more than or equal to the remaining clock time for the
     saved timer, the sleep time is set to the remaining clock time.  The
     state of the previous timer is restored after seconds has passed.

     This function is implemented using setitimer(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);  such a function would
     not restart after signals, but would not interfere with other uses of
     setitimer.

RETURN VALUES
SEE ALSO
     setitimer(2),  sigpause(2),  usleep(3)

HISTORY
     A sleep() function appeared in Version 7 AT&T UNIX.

BSD Experimental                April 19, 1991                               1