jacques,
Since there could be a whole bunch: 
sub ENV { defined $ENV{$_[0]} ? $ENV{$_[0]} : 'undefined' }
print "$_ is ", ENV($_), "\n" for qw(many environment variables);

[download]

Cheers - L~R

In reply to Re: Setting values for undefined environment variables by Limbic~Region
in thread Setting values for undefined environment variables by jacques

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