Cron is a very usefull service in Linux systems that allows periodical execution of programs.
Terms ¶
The program that runs other programs periodically is called "cron".
The configuration file, that tells cron which programs should be run
periodically is called "crontab" and located in /etc/crontab.
One line in that file is called "cronjob".
But "crontab" is also a command that lets you add cronjobs.
Example ¶
The following entry in crontab means that uamt.py is executed
every day at 3:30 am:
30 3 * * * /home/mthoma/uamt.py
You can check if everything went fine with
mthoma@i13srv30:~> crontab -l
# DO NOT EDIT THIS FILE - edit the master and reinstall.
# (/tmp/crontab.DEZBGc installed on Sat Jan 4 14:35:03 2014)
# (Cronie version 4.2)
30 3 * * * /home/mthoma/uamt.py