There are many ways to do this. Here are a few not yet mentioned:

envpass.pl:

#!/usr/bin/perl -w 
use strict;
#set environment variables
$ENV{FOOBAR} = 10000;

#Set package level variables
package manic;
our $vroom = 10097;

#You can use Data::Dumper
package main;
use Data::Dumper;
    my $foobie = 19897;
open(H,qq|>junk.dat|) or die $!;

print H Data::Dumper->Dump([$foobie],[qw[foobie]]);
close(H);

1;
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envpass2.pl

#!/usr/bin/perl -w
use strict;
do 'envpass.pl';
print $ENV{FOOBAR};
print $manic::vroom;
#read in that data dumper stuff
my $stuff = `cat junk.dat`;
no strict 'vars';
eval($stuff);
print $foobie;
1;
[download]