NAME
sleep – suspend execution for an interval of time
SYNOPSIS
sleep seconds
DESCRIPTION
The sleep utility suspends execution for at least the given number of seconds. seconds must be a non-negative decimal value and may contain a fraction.
ASYNCHRONOUS EVENTS
- SIGALRM
-
Terminate early, with a zero exit status.
EXIT STATUS
The sleep utility exits 0 on success, and >0 if an error occurs.
EXAMPLES
Wait five seconds before running a command:
$ sleep 5; echo Hello, World!
List a file twice per second:
while ls -l file; do sleep 0.5 done
SEE ALSO
STANDARDS
The sleep utility is compliant with the IEEE Std 1003.1-2008 (“POSIX.1”) specification.
Support for fractional seconds is an extension to that specification.
HISTORY
A sleep utility first appeared in Version 4 AT&T UNIX.
This implementation of sleep first appeared in 4.3BSD-Tahoe.