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sleep(3) [debian man page]

SLEEP(3)						     Linux Programmer's Manual							  SLEEP(3)

sleep - sleep for the specified number of seconds SYNOPSIS
#include <unistd.h> unsigned int sleep(unsigned int seconds); DESCRIPTION
sleep() makes the calling thread sleep until seconds seconds have elapsed or a signal arrives which is not ignored. RETURN VALUE
Zero if the requested time has elapsed, or the number of seconds left to sleep, if the call was interrupted by a signal handler. CONFORMING TO
POSIX.1-2001. BUGS
sleep() may be implemented using SIGALRM; mixing calls to alarm(2) and sleep() is a bad idea. Using longjmp(3) from a signal handler or modifying the handling of SIGALRM while sleeping will cause undefined results. SEE ALSO
alarm(2), nanosleep(2), signal(2), signal(7) COLOPHON
This page is part of release 3.44 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at GNU
2010-02-03 SLEEP(3)

Check Out this Related Man Page

ALARM(2)						     Linux Programmer's Manual							  ALARM(2)

alarm - set an alarm clock for delivery of a signal SYNOPSIS
#include <unistd.h> unsigned int alarm(unsigned int seconds); DESCRIPTION
alarm() arranges for a SIGALRM signal to be delivered to the calling process in seconds seconds. If seconds is zero, no new alarm() is scheduled. In any event any previously set alarm() is canceled. RETURN VALUE
alarm() returns the number of seconds remaining until any previously scheduled alarm was due to be delivered, or zero if there was no pre- viously scheduled alarm. CONFORMING TO
SVr4, POSIX.1-2001, 4.3BSD. NOTES
alarm() and setitimer(2) share the same timer; calls to one will interfere with use of the other. sleep(3) may be implemented using SIGALRM; mixing calls to alarm() and sleep(3) is a bad idea. Scheduling delays can, as ever, cause the execution of the process to be delayed by an arbitrary amount of time. SEE ALSO
gettimeofday(2), pause(2), select(2), setitimer(2), sigaction(2), signal(2), sleep(3), time(7) COLOPHON
This page is part of release 3.27 of the Linux man-pages project. A description of the project, and information about reporting bugs, can be found at Linux 2008-06-12 ALARM(2)

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