O monks, hear my plea for enlightenment:

Is there a graceful way to test whether a particular external program is available? I could do a system("which foo"), but that wouldn't be portable. I could attempt to execute foo and test for an error, but I don't actually want to execute foo yet, I just want to do an initial test to see whether there's any problem with the user's configuration. I could split $ENV{PATH} and look in every directory it contains, but that would be a lot of work.

On a related note, why does use of $ENV{PATH} with the -T pragma cause an error/warning, and is there a good workaround? I'm modifying someone else's CGI script to try to make it do better error checking.

Thanks in advance, O monks!

Thanks, all, for the suggestions!! I'm going to go with Aristotle's method, because it's someone else's project, and they might not want me to submit a patch that adds dependencies.

In reply to checking external program for availability? by bcrowell2

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