Two comments:

Your solution suffers from a race condition, and could allow two instances of the script to run at the same time.

A couple of people mentioned using a non-blocking flock. That's a great simple solution, but it comes with a major caveat: It's doesn't work or it's unreliable on some file systems (notably NFS). Also, I don't know if it'll work on Windows.

In reply to Re: Mechanism for ensuring only one instance of a Perl script can only run? by ikegami
in thread Mechanism for ensuring only one instance of a Perl script can only run? by redapplesonly

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