The at command

The at command can be used to submit single-run jobs, scripts, or commands to the cron daemon to be executed at a later time (anywhere from 10 minutes to a few days). Anything having a more frequent requirement than that or to be done on a regular basis should be done through crontab.

at time

• specifies the time for commands to be run as the user, whether the user is online or not.
• commands are read from stdin at an at> prompt
• non-redirected output is automatically mailed to user’s local mail account
• used for one time run scenario only
• provides job number given when queued.