At

The at service allows a command-line task to be executed at a specified future time. Unlike the cron service, at commands are only executed once, and cannot be scheduled to run at a recurring interval.

The at service is controlled by the atd daemon and is installed by default in most distributions.

= How to use = $ at 12:15 at> echo "i like linuxquestions.org" at> ctrl-d at>  job 17 at Tue Aug 11 12:15:00 2009 echo "i like linuxquestions.org" | at 12:15 tomorrow Execute command at this time, 1 week from now at now + 1 week 4 am 3 days from now at 4:00 am + 3 days
 * General usage: at time date  - at HH:MM MM/DD/YY - at 12:15 PM today - at 12:15 tomorrow
 * Times and Dates are accepted in several formats 02/01/09 or 02.01.09 - 4:00 pm or 16:00
 * When you enter at with a time and date, you then see the at prompt at>. Enter the commands you want executed, and when done, with your cursor at the beginning of a new line, do a ctrl-d
 * at assumes 'tomorrow' if it is already past the time given and you do not include a date
 * The same could be executed by typing:
 * Using numbers and units

= View Scheduled Jobs = Use the -l option to list the at-queue. Also use the command atq: at -l atq

= Remove Scheduled Jobs = Use the -d option to remove jobs from the at-queue. Also use the command atrm: at -d atq

= See also =
 * atd
 * atq
 * atrm
 * batch
 * command
 * cron
 * nice
 * watch

= External Links =
 * wikipedia.org : Daemon
 * at man page