#!/usr/bin/perl -w
use strict;
use CGI::Carp;
my $dir = "/tmp/wwwtrash";
opendir DIR, "$dir" or die "Couldn't open directory $dir: $!";
my @files = grep { (-f "$dir/$_") && (-M "$dir/$_" > 1) } readdir(DIR);
closedir DIR;
unlink @files or die "Couldn't unlink files in $dir: $!";

# rest of your script