http://qs1969.pair.com?node_id=217341


in reply to How to verify if a daemon is up and running ?

The decent method for you to do this is to create a lock file...

On startup your prgy would read in a pid, and do a grep in the process list for that pid (and perhaps the name of your prgy ( to prevent collisions with reused pids)). If it finds the pid, it exits, if not, it continues and writes out its own pid ($$).

This is a pretty standard method to prevent dupe processes...