USLEEP(1) General Commands Manual USLEEP(1)NAME
usleep - sleep some number of microseconds
SYNOPSIS
usleep [number]
DESCRIPTION
usleep sleeps some number of microseconds. The default is 1.
OPTIONS --usage Show short usage message.
--help, -?
Print help information.
-v, --version
Print version information.
BUGS
Probably not accurate on many machines down to the microsecond. Count on precision only to -4 or maybe -5.
AUTHOR
Donald Barnes <djb@redhat.com>
Erik Troan <ewt@redhat.com>
Red Hat, Inc USLEEP(1)
Check Out this Related Man Page
USLEEP(3) BSD Library Functions Manual USLEEP(3)NAME
usleep -- suspend execution for interval of microseconds
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <unistd.h>
int
usleep(useconds_t microseconds);
DESCRIPTION
The usleep() function suspends execution of the calling process until either the number of microseconds specified by microseconds have
elapsed or a signal 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.
The microseconds argument must be less than 1,000,000. If the value of microseconds is 0, then the call has no effect.
RETURN VALUES
On successful completion, usleep() returns 0. Otherwise, it returns -1 and sets errno to indicate the error.
ERRORS
The usleep() function may fail if:
[EINVAL] The microseconds interval specified 1,000,000 or more microseconds.
SEE ALSO nanosleep(2), sleep(3)STANDARDS
The usleep() function conforms to X/Open Portability Guide Issue 4, Version 2 (``XPG4.2''). It later appeared in the POSIX standard, but in
IEEE Std 1003.1-2004 (``POSIX.1'') it was marked as legacy and the use of nanosleep(2) was recommended instead. The IEEE Std 1003.1-2008
(``POSIX.1'') revision removed usleep() from the specification.
HISTORY
The usleep() function appeared in 4.3BSD.
BSD April 29, 2010 BSD