This is the built-in automation tool for users of OpenBSD to set up task scheduling. Each user can have a separate crontab that holds several cronjobs to be executed periodically by a cron daemon. Synopsis:
# Backup table mytable and every Saturday 9:30am 30 9 * * 6 /usr/bin/perl /path/to/scripts/backup.pl
To edit a cronjob, do: $crontab -l > temp.txt --> write current cronjob to file $pico temp.txt (or use nano, of vi) --> make changes $crontab temp.txt --> install back the job
Alternate way: $export EDITOR=/path/to/pico (or nano, vi is default) $crontab -e -->edit and save new jobs
Important: Cron has a different set of environmental variable settings from that of the user's. For example, the user's $PATH setting might have /sbin:/usr/sbin:/usr/local/sbin, but cron's $PATH might not. Sometimes extra environmental settings are required for a job to run inside cron. To make these setting, simply edit the cron, and add the neccessary settings on top of file (ex. add PATH=$PATH:/sbin:/usr/sbin)
Note: should a cronjob produce any error message, this message will be mailed to the owner of that cronjob. Simply type æmailÆ to open the email folder and view the cron daemon mail.