#!/usr/bin/perl
use warnings;
use strict;

use Archive::Zip qw( :ERROR_CODES );

my $zip = Archive::Zip->new();

$zip->read('tst.zip') == AZ_OK or die "read error\n";
$zip->addFile('tst2/s2.tst');
$zip->overwrite()     == AZ_OK or die "write error\n";