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
STANDARDS
The sleep() function conforms to
IEEE Std 1003.1-1990 (“POSIX.1”).
HISTORY
A sleep() function appeared in
Version 7 AT&T UNIX.