I would create a pid file that tells you whether your program is running. See File::Pid or File::Pid::Quick. You can also look at Highlander - allow only one invocation at a time of an expensive CGI script and RFC: A new module to help avoid running multiple instances of the same script (via cron, for example) for discussions.

In reply to Re: How can i check my script is already running? by Corion
in thread How can i check my script is already running? by shekarkcb

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