forked from vincent/notebook
50 lines
1.6 KiB
Markdown
50 lines
1.6 KiB
Markdown
# cron
|
|
|
|
```
|
|
# * * * * * command to execute
|
|
# │ │ │ │ │
|
|
# │ │ │ │ │
|
|
# │ │ │ │ └───── day of week (0 - 6) (0 to 6 are Sunday to Saturday, or use names; 7 is Sunday, the same as 0)
|
|
# │ │ │ └────────── month (1 - 12)
|
|
# │ │ └─────────────── day of month (1 - 31)
|
|
# │ └──────────────────── hour (0 - 23)
|
|
# └───────────────────────── min (0 - 59)
|
|
```
|
|
[test cron](https://crontab.guru/)
|
|
See also
|
|
- [wikipedia/cron](http://en.wikipedia.org/wiki/Cron)
|
|
|
|
## cron directories
|
|
You can create directories that run cron commands. Taken from the `Ubuntu`
|
|
distro:
|
|
```txt
|
|
# /etc/crontab: system-wide crontab
|
|
# Unlike any other crontab you don't have to run the `crontab'
|
|
# command to install the new version when you edit this file
|
|
# and files in /etc/cron.d. These files also have username fields,
|
|
# that none of the other crontabs do.
|
|
|
|
SHELL=/bin/sh
|
|
PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
|
|
|
|
# m h dom mon dow user command
|
|
17 * * * * root cd / && run-parts --report /etc/cron.hourly
|
|
25 6 * * * root test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.daily )
|
|
47 6 * * 7 root test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.weekly )
|
|
52 6 1 * * root test -x /usr/sbin/anacron || ( cd / && run-parts --report /etc/cron.monthly )
|
|
```
|
|
|
|
## run every weekday at midnight
|
|
```sh
|
|
0 0 * * 0-5
|
|
```
|
|
|
|
## edit cronjobs
|
|
```sh
|
|
$ sudo crontab -e
|
|
```
|
|
|
|
## user crontab lcation
|
|
|
|
`/var/spool/cron/crontabs`
|