Introduction crontab-Operates the daemon of each user and the schedule of the execution. Some parameters Description crontab file [-u user] - replaces the current crontab with the specified file. Crontab - [- u user] - replaces the current crontab. crontab-1 [user] with standard input, lists the current crontab. crontab-e [user] - edit the user's current crontab. crontab-d [user] - Delete the current crontab. Crontab-c dir- specifies the catalog of crontabs. CRONTAB file format: M H D m D cmd. M: Minute (0-59). H: Hours (0-23). D: Day (1-31). M: Month (1-12). D: The sky within a week (0 ~ 6, 0 is Sunday). CMD To run the program, the program is sent to the SH execution, this shell has only three environment variables of User, HOME, Shell. Below is an example of an example file: #MIN HOR DAY MONTH Dayofweek Command # 6:10 per day 10 6 * * * Date # Every two hours 0 * / 2 * * * Date # 11 points to 8 points in the morning Two hours, 8:00 23-7 / 2, 8 * * * Date # Every month 4 and each worship of the worship of the worship 3 in the morning 11:00 11 4 * MON-WED DATE # 1 Month Day 4 0 4 1 Jan * Date Sample $ crontab -l Lists users' current crontab. # Hour day month dayofweek Command 10 6 * * * Date 0 * / 2 * * * Date 0 23-7 / 2 , 8 * * * Date
