| <?php
// read the post from PayPal system and add 'cmd'
$req = 'cmd=_notify-validate';
foreach ($_POST as $key => $value) {
$value = urlencode(stripslashes($value));
$req .= "&$key=$value";
}
// post back to PayPal system to validate
$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) {
// HTTP ERROR
}
else {
fputs ($fp, $header . $req);
while (!feof($fp)) {
$res = fgets ($fp, 1024);
if (strcmp ($res, "VERIFIED") == 0) {
// check the payment_status is Completed
// check that txn_id has not been previously processed
// check that receiver_email is your Primary PayPal email
// check that payment_amount/payment_currency are correct
// process payment
// echo the response
echo "The response from IPN was: " .$res ."
";
//loop through the $_POST array and print all vars to the screen.
foreach($_POST as $key => $value) echo $key." = ". $value."
";
}
else if (strcmp ($res, "INVALID") == 0) {
// log for manual investigation
// echo the response
echo "The response from IPN was: " .$res ."";
}
}
fclose ($fp);
}
?>
| 
