comment on

Depending on your specific requirements, use one of

Proc::PID_File - takes care of PID file use for you.
Proc::PID::File - OO way to do the above
Linux::PID - for managing multi-threaded applications' PPID's on Linux (you still have to deal with files yourself).

CPAN is a wonderful thing, yes? There are also a number of pid server daemons that can track these types of things well, and Perl modules to talk to them. Or, you can solve the problem in your cron script with the insanely simple:

#!/bin/bash

if (ps ax |grep -q "my_perl_script_name") ; then exit; fi
my_perl_script_name
[download]

require General::Disclaimer;

All code, unless otherwise noted, is untested

"All it will give you though, are headaches after headaches as it misinterprets your instructions in the most innovative yet useless ways." - Maypole and I - Tales from the Frontier of a Relationship (by Corion)

In reply to Re: Checking for multiple instances by radiantmatrix
in thread Checking for multiple instances by MarkNo1

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