* * * * * * | | | | | | | | | | | +-- Year (range: 1900-3000) | | | | +---- Day of the Week (range: 1-7, 1 standing for Monday) | | | +------ Month of the Year (range: 1-12) | | +-------- Day of the Month (range: 1-31) | +---------- Hour (range: 0-23) +------------ Minute (range: 0-59)
Examples:
* * * * * * Each minute
59 23 31 12 5 * One minute before the end of year if the last day of the year is Friday
59 23 31 DEC Fri * Same as above (different notation)
45 17 7 6 * * Every year, on June 7th at 17:45
45 17 7 6 * 2001,2002 Once a year, on June 7th at 17:45, if the year is 2001 or 2002
0,15,30,45 0,6,12,18 1,15,31 * 1-5 * At 00:00, 00:15, 00:30, 00:45, 06:00, 06:15, 06:30,
06:45, 12:00, 12:15, 12:30, 12:45, 18:00, 18:15,
18:30, 18:45, on 1st, 15th or 31st of each month, but not on weekends
*/15 */6 1,15,31 * 1-5 * Same as above (different notation)
0 12 * * 1-5 * (0 12 * * Mon-Fri *) At midday on weekdays
* * * 1,3,5,7,9,11 * * Each minute in January, March, May, July, September, and November
1,2,3,5,20-25,30-35,59 23 31 12 * * On the last day of year, at 23:01, 23:02, 23:03, 23:05,
23:20, 23:21, 23:22, 23:23, 23:24, 23:25, 23:30,
23:31, 23:32, 23:33, 23:34, 23:35, 23:59
0 9 1-7 * 1 * First Monday of each month, at 9 a.m.
0 0 1 * * * At midnight, on the first day of each month
* 0-11 * * * Each minute before midday
* * * 1,2,3 * * Each minute in January, February or March
* * * Jan,Feb,Mar * * Same as above (different notation)
0 0 * * * * Daily at midnight
0 0 * * 3 * Each Wednesday at midnight
In extended mode, crontab notation may be abridged by omitting the rightmost asterisks.
Examples: (only for extended mode)
Full notation Abridged notation * * * * * * 59 23 31 12 5 2003 59 23 31 12 5 2003 59 23 31 12 5 * 59 23 31 12 5 45 17 7 6 * * 45 17 7 6 0,15,30,45 0,6,12,18 1,15,31 * * * 0,15,30,45 0,6,12,18 1,15,31 0 12 * * 1-5 * 0 12 * * 1-5 * * * 1,3,5,7,9,11 * * * * * 1,3,5,7,9,11 1,2,3,5,20-25,30-35,59 23 31 12 * * 1,2,3,5,20-25,30-35,59 23 31 12 0 9 1-7 * 1 * 0 9 1-7 * 1 0 0 1 * * * 0 0 1 * 0-11 * * * * * 0-11 * * * 1,2,3 * * * * * 1,2,3 0 0 * * * * 0 0 0 0 * * 3 * 0 0 * * 3
Both in classic and extended modes, nnCron users can use a «nonstandard» character «?» in the first four fields of cron format. It stands for time of nnCron startup, i. e. when a field is processed, startup time will be substituted for the question mark: minutes for Minute field, hour for Hour field, day of the month for Day of month field and month for Month field.
For example, if you write the following:
Time: ? ? * * * *
the task will be executed on nnCron startup and then will be executed daily at the same time (unless the user doesn’t restart nnCron, of course): question marks will be «replaced» by nnCron startup time. For example, if nnCron was started at 8:25, question marks will be substituted this way:
Time: 25 8 * * * *
Some more examples:
\ task will be executed only on nnCron startup \ (this has the sane effect as "Time: START-TIME") Time: ? ? ? ? * * \ task will be executed on nnCron startup (e.g. at 10:15) \ and then will be executed again each hour: \ at 11:15, 12:15, 13:15 etc. Time: ? * * * * * \ task will be started each minute after nnCron startup until the next hour starts. \ The next day, if nnCron has not been restarted in the meanwhile, \it will be executed again each minute during the same hour. Time: * ? * * * * \ task will be executed daily, every five minutes, \ during the hour when nnCron was started. Time: */5 ? * * * *