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My question:

I have an if statement in perl where I attempt to detect via environment variables at the time of launching the perl script whether it was launched via a cron job or via normal execution through the shell.

Is there any way to set an environment variable in the crontab itself that a program launched by cron would be able to access?

Essentially, I want this in the top of my crontab:


* * * * *

And in this if statement:

if ( $ENV{'COMPANYCRON'} eq '1' ) {
    $job_creator = "cron";

Is there a way to do this? Or a better approach to keeping track of cron jobs?

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Some cron daemons (e.g. Vixie cron on Debian/Ubuntu) allows the exact same syntax you wrote in your example. On other systems (RHEL etc.), use something like this in your crontab:

* * * * * export COMPANYCRON=1; 
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