crontab [-u user] file
usage: crontab [-u user] file
crontab [ -u user ][ -i ] { -e | -l | -r }
(default operation is replace, per 1003.2)
-e (edit user's crontab)
-l (list user's crontab)
-r (delete user's crontab)
-i (prompt before deleting users crontab)
List tasks for current user
crontab -l
List tasks for other user
sudo crontab -l -u <user>
Edit tasks for current user
crontab -e
Edit tasks for other user
sudo crontab -e -u <user>
Five asterix * * * * *
First * : minutes (0-59)
Second * : hours (0-23)
Third * : day of the month (1-31)
Fourth * : month (1-12)
Fifth * : day of the week (0-6 or 1-7)