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SLEEP(3)                   Library Functions Manual                   SLEEP(3)

NAME
     sleep - suspend process execution for interval of seconds

LIBRARY
     Standard C Library (libc, -lc)

SYNOPSIS
     #include <unistd.h>

     unsigned int
     sleep(unsigned int seconds);

DESCRIPTION
     The sleep() function suspends execution of the calling process until
     either the number of seconds specified by seconds have elapsed or a
     signal is delivered to the calling process and its action is to invoke a
     signal-catching function or to terminate the process.  The suspension
     time may be longer than requested due to the scheduling of other activity
     by the system.

RETURN VALUES
     If the sleep() function returns because the requested time has elapsed,
     the value returned will be zero.  If the sleep() function returns due to
     the delivery of a signal, the value returned will be the unslept amount
     (the request time minus the time actually slept) in seconds.

SEE ALSO
     nanosleep(2), usleep(3)

STANDARDS
     The sleep() function conforms to IEEE Std 1003.1-1990 ("POSIX.1").

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

NetBSD 10.99                     June 4, 1993                     NetBSD 10.99