sleep
- suspend process execution for an interval measured in seconds
LIBRARY
Lb libc
SYNOPSIS
#include <unistd.h> unsigned int
sleep (unsigned int seconds);
DESCRIPTION
The
sleep ();
function suspends execution of the calling process until either
Fa 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
Fa 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
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.
