I've used LockFile::Simple for similar problems where I can only have one copy of a program running at a time. This module handles the waiting, retrying, cleaning up of stale lock files, and more.

The problem gets a bit more complicated if you want to have a maximum of N copies running at a time.

-- Eric Hammond

In reply to Re: Maximum # of concurrent runs by esh
in thread Maximum # of concurrent runs by warthurton

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