use Fcntl qw( flock );
sub write_hits {
    open  HITSW, "+< $_[0]" or die $!;
    flock HITSW, LOCK_EX;

    my $read_hits = <HITSW>;
    chomp $read_hits;
    ++$read_hits;

    seek HITSW,0,0 or die $!;
    print HITSW $read_hits, $/ or die $!;
    close HITSW or die $!;
    return $read_hits;
}