NAME    [Toc]    [Back]

     sleep -- suspend process execution for an interval measured in seconds

LIBRARY    [Toc]    [Back]

     Standard C Library (libc, -lc)

SYNOPSIS    [Toc]    [Back]

     #include <unistd.h>

     unsigned int
     sleep(unsigned int seconds);

DESCRIPTION    [Toc]    [Back]

     The sleep() function suspends execution of the calling process until
     either seconds seconds have elapsed or a signal is delivered to the
     process and its action is to invoke a signal-catching function or to terminate
 the process.  System activity may lengthen the sleep by an indeterminate
 amount.

     This function is implemented using nanosleep(2) by pausing for seconds
     seconds or until a signal occurs.	Consequently, in this implementation,
     sleeping has no effect on the state of process timers, and there is no
     special handling for SIGALRM.

RETURN VALUES    [Toc]    [Back]

     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 requested time minus the time actually slept) in seconds.

SEE ALSO    [Toc]    [Back]

     nanosleep(2), usleep(3)

STANDARDS    [Toc]    [Back]

     The sleep() function conforms to ISO/IEC 9945-1:1990 (``POSIX.1'').

HISTORY    [Toc]    [Back]

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


FreeBSD 5.2.1		       February 13, 1998		 FreeBSD 5.2.1