Perl has flock command for this kind of problems.

This recent discussion might be of interest: File lock demo

please be aware that this also depends on the OS, I've tested it on Win.

(you havent been explicitly telling us which one you use, but crontab is usually more *nix'ish)

Cheers Rolf
(addicted to the 𐍀𐌴𐍂𐌻 Programming Language :)
Wikisyntax for the Monastery

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

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