Gpodder in cron job
- The hyphen operator allows you to specify a range of values.For example, if you have 1,3,5 in the Hour field, the task will run at 1 am, 3 am and 5 am. , - The comma operator allows you to specify a list of values for repetition.If you have the asterisk symbol in the Hour field, it means the task will be performed each hour. * - The asterisk operator means any value or always.The first five fields may contain one or more values, separated by a comma or a range of values separated by a hyphen. Crontab Syntax and Operators #Įach line in the user crontab file contains six fields separated by a space followed by the command to be run. directories, and the scripts will be executed every hour/day/week/month. In most Linux distributions you can also put scripts inside the /etc/cron. The /etc/crontab file and the scripts inside the /etc/cron.d directory are system-wide crontab files that can be edited only by the system administrators. In Red Hat based distributions such as CentOS, crontab files are stored in the /var/spool/cron directory, while on Debian and Ubuntu files are stored in the /var/spool/cron/crontabs directory.Īlthough you can edit the user crontab files manually, it is recommended to use the crontab command. Users’ crontab files are named according to the user’s name, and their location varies by operating systems. The system-wide crontab files and individual user crontab files. What is Crontab File #Ĭrontab (cron table) is a text file that specifies the schedule of cron jobs. The cron jobs can be scheduled to run by a minute, hour, day of the month, month, day of the week, or any combination of these. Or data, updating the system with the latest security patches, checking the disk space usage
These tasks are called cron jobs and are mostly used to automate system maintenance or administration.įor example, you could set a cron job to automate repetitive tasks such as backing up databases Cron is a scheduling daemon that executes tasks at specified intervals.