Crontab

Crontab is the equivelant of the scheduler in Windows.

Crontab Commands

	crontab -e		Edit your crontab file, or create one if it doesn't already exist.
	crontab -l		Display your crontab file.
	crontab -r		Remove your crontab file.
	crontab -v		Display the last time you edited your crontab file.

Crontab File

A crontab file has five fields for specifying day , date and time followed by the command to be run at that interval.

*     *   *   *    *  command to be executed
-     -    -    -    -
|     |     |     |     |
|     |     |     |     +----- day of week (0 - 6) (Sunday=0)
|     |     |     +------- month (1 - 12)
|     |     +--------- day of month (1 - 31)
|     +----------- hour (0 - 23)
+------------- min (0 - 59)

Disable Email

By default cron jobs sends a email to the user account executing the cronjob. If this is not needed put the following command At the end of the cron job line .

>/dev/null 2>&1