RnC,
This is basic implementation that you can expand as you see fit. It is pretty fragile in the assumptions which means you will have to add your own error handling. 
#!/usr/bin/perl
use strict;
use warnings;

for my $file ( @ARGV ) {
    if ( ! open(INPUT, '<', $file) ) {
        warn "Unable to open $file - skipping!\n";
        next;
    }
    while ( <INPUT> ) {
        print and next if ! /\$\w+/;
        $_ =~ s/\$(\w+)/$ENV{$1}/g;
        print;
    }
}

[download]

Cheers - L~R

In reply to Re: printing enviroment vars from regex by Limbic~Region
in thread printing enviroment vars from regex by RnC

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