use strict;
use Tie::File;

tie my @file1, 'Tie::File', 'file1.txt' or die;
tie my @file2, 'Tie::File', 'file2.txt' or die;

@file1 = grep { my $name = $_; ! grep {$_ eq $name} @file2 } @file1;

##</code><code>##

nick
peter
adam
wolfgang
antony
mike