#!perl
use strict;
use warnings;
use autodie;

use File::Find::Rule;
use File::DosGlob 'glob';

my ($search) = @ARGV or die "need a directory to search";

sub found {
    my ($name, $path, $full) = @_;
    warn "Warning: $full has size ZERO" # outputs to STDERR
        unless $name ~~ ['empty.txt', 'sample.txt']; # Perl v5.10+
#        unless $name eq 'empty.txt' or $name eq 'sample.txt';
}

File::Find::Rule->file->empty->exec(\&found)->in($search);