#!/usr/bin/perl

use strict;

# Change this variable to where you want
# your count files to be.
my $dir = "counter";

my ($id,$nr) = split(/=/, $ENV{'QUERY_STRING'});
$nr = ($nr/$nr==1)? $id : die;

my $file = "$dir$nr.txt";

# Read count
open(FILE, "< $file");
my $count = <FILE>;

# Increment count
open(FILE, "> $file") || die "Can't open $file: $!\n";
print FILE ++$count;

print "Content-type: text/plain\n\ncount=$count";

exit;