Crontab useful keywords

In this short article I would like to remind you few useful keywords which you can use to describe your cron jobs in simple way.

Their names sufficiently describes how specified keyword works, but I prepared a short table with description where you can also find equivalent for keyword in regular “cron language” and how it acts.

Keyword Equivalent Description
@yearly 0 0 1 1 * Run job every year
@daily 0 0 * * * Run job every day
@hourly 0 * * * * Run job every full hour
@reboot Run job at system startup

To edit your crontab, you use:
crontab -e

To see actual crontab for your current user:
crontab -l

Here is a real-life example of keywords usage in crontab:

@daily /usr/sbin/cron-apt
@reboot /usr/sbin/cron-apt

It runs cron-apt (auto update tool for your aptitude) command every day and after every reboot.
You can read more about cron-apt here.



Leave a Comment

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>