<?php
function write2LogFile( $message, $file = "mylog.txt" ) { $file = fopen($file, "a"); fputs($file, "[".date('d-m-Y')."] ".$message."\n"); fclose($file); }
$req = 'cmd=_notify-validate';
foreach ($_POST as $key => $value)
{
    $value = urlencode(stripslashes($value));
    $req .= "&$key=$value";
}
$header .= "POST /cgi-bin/webscr HTTP/1.0\r\n";
$header .= "Content-Type: application/x-www-form-urlencoded\r\n";
$header .= "Content-Length: " . strlen($req) . "\r\n\r\n";
$fp = fsockopen ('www.paypal.com', 80, $errno, $errstr, 30);
if (!$fp) {
    write2LogFile( "ERROR Can not connect to paypal!" );
}
else
{
    fputs ($fp, $header . $req);
    while (!feof($fp))
    {
        $res = fgets ($fp, 1024);
        if (strcmp ($res, "VERIFIED") == 0)
        {
            $payment_status = $_POST['payment_status'];
            $transaction_id = $_POST['txn_id'];
            $payer_email    = $_POST['payer_email'] );
            $custom_field   = $_POST['custom'];

            if ( $payment_status == 'Completed' )
            {
                // Payment/Donation is completed. Give points here
            }
            else if ( $payment_status == 'Canceled_Reversal' )
            {
                // Player was stupid enough to make a dispute/claim or used a stolen credit card info
                // Basically we ban his account here.
            }
        }
    }
    fclose ($fp);
}
?>