if ($ENV{$val}) {

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That's a truth test, not a defined-ness test or existence test. I think you want: 
if (defined $ENV{$val}) {

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there, or else you'll be saying "undefined" for envars that are 0 or empty.

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

In reply to •Re^2: Setting values for undefined environment variables by merlyn
in thread Setting values for undefined environment variables by jacques

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