sub erase_files {
    my $period = 10;
    opendir(DIR, '/your/tmp/dir') or die $!;
    my @files = grep {!(/^\./) && /\.zip$/} readdir(DIR);
    close DIR;
    my $now = localtime;
    for my $file (@files) {
        my $ftime = (stat($file))[9];
        if(($now - $ftime) > $period*3600) { unlink $file }
    }
}