cron - How to get a unix script to run every 15 seconds?

Question

I've seen a few solutions, including watch and simply running a looping (and sleeping) script in the background, but nothing has been ideal.

I have a script that needs to run every 15 seconds, and since cron won't support seconds, I'm left to figuring out something else.

What's the most robust and efficient way to run a script every 15 seconds on unix? The script needs to also run after a reboot.

Answer 1

If you insist of running your script from cron:

* * * * * /foo/bar/your_script
* * * * * sleep 15; /foo/bar/your_script
* * * * * sleep 30; /foo/bar/your_script
* * * * * sleep 45; /foo/bar/your_script

and replace your script name&path to /foo/bar/your_script