The origin of the name cron is from the Greek word for time, χρόνος
For reference, here’s how to create a quick cron job task that can run on a recurring schedule on Linux. You have one of two options to get a script to run, either dropping a script into one of the following folders on a linux machine or creating a line entry in a crontab -e file.
Easy – Drop a script into one of the following folders:
- /etc/cron.hourly
- /etc/cron.daily
- /etc/cron.weekly
- /etc/cron.monthly
Harder – add a path/script to execute to the crontab -e file with the unique cron timing prefix. Start by opening the cron timings file by running the following at a terminal.
crontab -e
Then you can add a line at the end of the comments with the following format:
# ┌───────────── minute (0 - 59) # │ ┌───────────── hour (0 - 23) # │ │ ┌───────────── day of month (1 - 31) # │ │ │ ┌───────────── month (1 - 12) # │ │ │ │ ┌───────────── day of week (0 - 6) (Sunday to Saturday; # │ │ │ │ │ 7 is also Sunday on some systems) # │ │ │ │ │ # │ │ │ │ │ # * * * * * /path/path/command_to_execute
So for example if you wanted to run a script that runs every hour on the hour,
0 */1 * * * /path/to/run.sh
Or if you wanted it to run every minute, or 5 or 15 minutes,
*/1 * * * * /path/to/run.sh */5 * * * * /path/to/run.sh */15 * * * * /path/to/run.sh
Or if you wanted it to run every night at midnight,
0 0 */1 * * /path/to/run.sh
I think you get the point. The spec for changing the run schedule for a cron job is unique, here’s a website that can help turn your *****’s into something you can quickly make sense of.
https://crontab.guru/#*/1_*_*_*_*
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