USLEEP(3) Linux Programmer's Manual USLEEP(3)NAME
usleep - suspend execution for microsecond intervals
SYNOPSIS
#include <unistd.h>
void usleep(unsigned long usec);
int usleep(unsigned long usec); /* SUSv2 */
DESCRIPTION
The usleep() function suspends execution of the calling process for usec microseconds. The sleep may be lengthened slightly by any system
activity or by the time spent processing the call.
RETURN VALUE
None (BSD). Or: 0 on success, -1 on error (SUSv2).
ERRORS
EINTR Interrupted by a signal.
EINVAL usec is not smaller than 1000000. (On systems where that is considered an error.)
CONFORMING TO
BSD 4.3. The SUSv2 version returns int, and this is also the prototype used by glibc 2.2.2. Only the EINVAL error return is documented by
SUSv2.
NOTES
The interaction of this function with SIGALRM and other timer functions such as sleep(), alarm(), setitimer(), nanosleep() is unspecified.
This function is obsolete. Use nanosleep(2) or setitimer(2) instead.
SEE ALSO alarm(2), getitimer(2), nanosleep(2), select(2), setitimer(2), sleep(3)
2001-04-02 USLEEP(3)
Check Out this Related Man Page
USLEEP(3) Linux Programmer's Manual USLEEP(3)NAME
usleep - suspend execution for microsecond intervals
SYNOPSIS
#include <unistd.h>
int usleep(useconds_t usec);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
usleep(): _BSD_SOURCE || _XOPEN_SOURCE >= 500
DESCRIPTION
The usleep() function suspends execution of the calling process for (at least) usec microseconds. The sleep may be lengthened slightly by
any system activity or by the time spent processing the call or by the granularity of system timers.
RETURN VALUE
0 on success, -1 on error.
ERRORS
EINTR Interrupted by a signal; see signal(7).
EINVAL usec is not smaller than 1000000. (On systems where that is considered an error.)
CONFORMING TO
4.3BSD, POSIX.1-2001. POSIX.1-2001 declares this function obsolete; use nanosleep(2) instead. POSIX.1-2008 removes the specification of
usleep().
On the original BSD implementation, and in glibc before version 2.2.2, the return type of this function is void. The POSIX version returns
int, and this is also the prototype used since glibc 2.2.2.
Only the EINVAL error return is documented by SUSv2 and POSIX.1-2001.
NOTES
The type useconds_t is an unsigned integer type capable of holding integers in the range [0,1000000]. Programs will be more portable if
they never mention this type explicitly. Use
#include <unistd.h>
...
unsigned int usecs;
...
usleep(usecs);
The interaction of this function with the SIGALRM signal, and with other timer functions such as alarm(2), sleep(3), nanosleep(2),
setitimer(2), timer_create(2), timer_delete(2), timer_getoverrun(2), timer_gettime(2), timer_settime(2), ualarm(3) is unspecified.
SEE ALSO alarm(2), getitimer(2), nanosleep(2), select(2), setitimer(2), sleep(3), ualarm(3), time(7)COLOPHON
This page is part of release 3.25 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
2007-07-26 USLEEP(3)
Hi,
I'm using the command usleep (500000) when compiling C++ on the SunOS platform, but it does not compile on a OSF1 platform?
Any ideas?
Thanks (5 Replies)
Hello,
Can anyone, please, guide me on the use of nanosleep. I'm learning threads. I want to introduce a delay (not nested for loops, something more customizable). Nanosleep looked useful (or any other form of customizable and easy-to-use delay). Sleep is too long. :) (2 Replies)
Hi,
I have encountered the following problem on Solaris 10:
I have a thread that is asleep on nanosleep (set to 24 hours).
Something that happens on another thread, causes the nanosleep to exit, even though the time has not elapsed.
The returned value is 0 (so it doesn't look like it... (1 Reply)
Hi All,
I need usleep command to use in one of my shell script. I am working on SunOS 5.9. Where usleep command is not available. Is there any way to use usleep command in SunOS.
Thanks In Advance,
chidhu (5 Replies)
Hi ,
How can I use floating point argument for sleep command in unix.I cannot use usleep as it is not suppported.
Also how can I find out that a file is in use at that particular instant only.(wether it is being read or written) (7 Replies)