sleep(1)sleep(1)NAMEsleep - Suspends execution for at least the specified time
SYNOPSISsleep seconds
STANDARDS
Interfaces documented on this reference page conform to industry stan‐
dards as follows:
sleep: XCU5.0
Refer to the standards(5) reference page for more information about
industry standards and associated tags.
OPTIONS
None
OPERANDS
Non-negative integer specifying the number of seconds for which execu‐
tion is to be suspended.
DESCRIPTION
The sleep command suspends execution of a process for at least the
interval specified by seconds, which can range from 0 to 2,147,483,647
seconds. Depending on system activity, the actual time of suspension
may be longer. See the sleep(3) reference page.
[Tru64 UNIX] seconds can be entered as a non-negative decimal, octal,
or hexadecimal value.
NOTES
If sleep receives a SIGALARM signal before process execution has
resumed, sleep takes one of the following actions: Terminates normally
with a 0 (zero) exit status. (See the sleep(3) reference page for more
information.) Ignores the signal Performs default processing
EXIT STATUS
The following exit values are returned: Execution was successfully sus‐
pended for at least the requested time, or a SIGALARM signal was
received. An error occurred.
EXAMPLES
To display a message at 4-minute intervals for 20 minutes, create a
shell script called remind containing the following:
for i do sleep 240; echo $i sleep 240; echo $i sleep 240; echo
$i sleep 240; echo $i sleep 240; echo $i done
To display the message Try calling NHK at 4-minute intervals,
enter: remind 'Try calling NHK' To run a command at regular
intervals, create a shell script containing the following:
while true do
date
sleep 60 done
This displays the date and time once a minute. To execute a
command after a specified interval, enter the following; (sleep
3600; echo Time\'s up) &
This displays the message “Time's up” after one hour.
ENVIRONMENT VARIABLES
The following environment variables affect the execution of sleep: Pro‐
vides a default value for the internationalization variables that are
unset or null. If LANG is unset or null, the corresponding value from
the default locale is used. If any of the internationalization vari‐
ables contain an invalid setting, the utility behaves as if none of the
variables had been defined. If set to a non-empty string value, over‐
rides the values of all the other internationalization variables.
Determines the locale for the interpretation of sequences of bytes of
text data as characters (for example, single-byte as opposed to multi‐
byte characters in arguments). Determines the locale for the format
and contents of diagnostic messages written to standard error. Deter‐
mines the location of message catalogues for the processing of LC_MES‐
SAGES.
SEE ALSO
Commands: wait(1)
Functions: alarm(3), pause(3), sigaction(2), sleep(3)
Standards: standards(5)sleep(1)