skeleton for “crontab -e”:
SHELL=/bin/sh
PATH=$HOME/bin:/bin:/usr/bin:/usr/local/bin:/usr/sbin/
#+------------------- Minute: 0 - 59
#| +---------------- Hour: 0 - 23
#| | +------------- Day of Month: 0 - 31
#| | | +---------- Month: 0 - 12 (or names: 3-letter abbrev.)
#| | | | +------- Day of Week: 0 - 7 (0 or 7 is Sun, or use names)
#| | | | |
#V V V V V
Older unix systems tended to employ individual crontab files.
More often now, Linux systems employ /etc/crontab which invokes anacron to run scripts in the following directories:
/etc/cron.hourly
/etc/cron.daily
/etc/cron.weekly
/etc/cron.monthly
Good packages usually have cron scripts for one of these.
