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| Newer page: | version 5 | Last edited on Tuesday, June 29, 2004 8:50:33 am | by AristotlePagaltzis | Revert |
| Older page: | version 4 | Last edited on Tuesday, June 29, 2004 7:32:46 am | by AristotlePagaltzis | Revert |
@@ -21,5 +21,17 @@
Users can also have their own cron tables, with commands run under their respective [UID]. These should be manipulated using the crontab(1) command. __crontab -e__ will launch your configured interactive TextEditor on your user crontab, which generally resides under __/var/spool/cron__.
!!! Running commands at standard intervals, revisited, and more
-With Vixie Cron (used in [*BSD] and some [LinuxDistribution]s such as [Debian] and RedHat) you can use __@reboot__
instead of the
time fields. Cron will then run that command at system startup
. This allows regular users to launch their own daemons, such as fetchmail(1). This feature first appeared
[in
FreeBSD 4.1 | http://www.freebsd.org/cgi/man.cgi?query=crontab&apropos=&sektion=5&manpath=FreeBSD+4.1-RELEASE&format=html].
+With Vixie Cron (used in [*BSD] and some [LinuxDistribution]s such as [Debian] and RedHat) you can use several special keywords
instead of a
time specification
. This [FreeBSD 4.1 manpage
| http://www.freebsd.org/cgi/man.cgi?query=crontab&apropos=&sektion=5&manpath=FreeBSD+4.1-RELEASE&format=html], where this feature first appears, lists the following keywords:
+
+|^ string |^ meaning
+| __@reboot__ | Run once, at startup.
+| __@yearly__ | Run once a year, "0 0 1 1 *".
+| __@annually__ | (sames as @yearly)
+| __@monthly__ | Run once a month, "0 0 1 * *".
+| __@weekly__ | Run once a week, "0 0 * * ".
+| __@daily__ | Run once a day, "0 0 * * *".
+| __@midnight__ | (same as @daily)
+| __@hourly__ | Run once an hour, "0 * * * *".
+
+__@reboot__ is particularly interesting, as cron will run such a command at system startup. This allows regular users to start their own daemons such as fetchmail(1) at boot time
.
