I'm a bit confused as to your scenario. I think you have something like the following:

You are trying to run example.exe from a perl script that you wrote. Unfortunately, example.exe requires that the MYVAR environment variable be set. To do this, you could do something like this in your perl script: 

$ENV{MYVAR} = "MYVAR value";

[download]
To elaborate, web servers (or at least Apache; I have little experience with others) tend to trim their environment so as to limit the amount of damage a black hat could wreak on a server where the environment was left in tact, so to speak. So, if you need a special environment variable set for something to run, you should set it explicitly as I demonstrated above.

thor

Feel the white light, the light within
Be your own disciple, fan the sparks of will
With all of us waiting, your kingdom will come

In reply to Re: Access to Windows Environment Variables by thor
in thread Access to Windows Environment Variables by PConD

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