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crontab [file ]
crontab options [user ]

Run crontab on your current crontab file, or specify a crontab file to add to the crontab directory. A privileged user can run crontab for another user by supplying a user after any of the options.

A crontab file is a list of commands, one per line, that will execute automatically at a given time. Numbers are supplied before each command to specify the execution time. The numbers appear in five fields, as follows:

Day of month
Day of week
	0-6, with 0 = Sunday

Use a comma between multiple values, a hyphen to indicate a range, and an asterisk to indicate all possible values. For example, assuming the crontab entries below:

59 3 * * 5	find / -print | backup_program

0 0 1,15 * *	echo "Timesheets due" | mail user

The first command backs up the system files every Friday at 3:59 a.m., and the second command mails a reminder on the 1st and 15th of each month.



Edit the user's current crontab file (or create one).


List the user's file in the crontab directory.


Delete the user's file in the crontab directory.

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