cron: Batchdaemon for UNIX

The cron command starts a process that executes commands at specified dates and times. Since cron never exits, it should be executed only once.
Regularly scheduled commands can be specified according to instructions found in crontab files.

The table of cronjobs is displayed (-l) or modified (-e) by the crontab utility.
crontab -e opens the crontab-file with the editor defined by the EDITOR variable.

Example


  $ crontab -l
  # Format:
  # min hour day/m month day/w cmd
  #
  # Monatserster, 09:00:
   0  9  1  *  *  /path/to/program1
  # 08:30 am erster Tag im Quartal
  30  8  1  1,4,7,10 *  /path/to/program2
  #
  # taeglich:
   0,15,30,45 7-21 *  *  *  /path/to/program3 > /dev/null 2>&1
   0  8  *  *  *  /path/to/program4
  # Montag
   0  9  *  *  1  /path/to/program5
  # Freitag im Februar bis November
   0 12  *  2-11  5  /path/to/program6