SLEEP(3) BSD Library Functions Manual SLEEP(3)NAMEsleep — 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 sig‐
nal 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 ALSOnanosleep(2), usleep(3)STANDARDS
The sleep() function conforms to ISO/IEC 9945-1:1990 (“POSIX.1”).
HISTORY
A sleep() function appeared in Version 7 AT&T UNIX.
BSD June 4, 1993 BSD