This works for 8 digits:

#!/usr/bin/perl

use strict;
use warnings;
use GD::Barcode::UPCE;

my $oGdBar;
print "=======================\nUPCE: 1234568";
$oGdBar = GD::Barcode->new( 'UPCE', '1234568' );
print "PTN:", $oGdBar->{text}, ':', $oGdBar->barcode(), "\n";
open OUT, '>', 'UPCE.png';
binmode OUT;
print OUT $oGdBar->plot->png;
close OUT;
undef $oGdBar;
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