junk.pl:

#! perl -slw
use strict;
use Junk;

our $ERROR_FILE = 'fred';

Junk::showIt();
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Junk.pm:

package main;
our $ERROR_FILE;

package Junk;
use strict;
use warnings;

sub showIt {
    print $ERROR_FILE;
}

1;
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C:\test>junk.pl
fred
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