I want to prevent my script running more than once at a time.
My current approach is
- create a semaphore file containing the pid of the running process
- read the file, if my process-id is not in it exit (you never know...)
- at the end of the processing, delete the file
In order to prevent the process from hanging, I set up a cron job to periodically check the file if its older then the maximum allowed running time and kills the process if it’s still running.
Is there a risk that I'm killing a wrong process?
Is there a better way to perform this as a whole?