Server port?

[bunder5]

Stupid question but why would it need the port contained inside the URL for redirection later on?

 

 

    /* The servername and serverport tells PayPal where the buyer
    should be directed back to after authorizing payment.
    In this case, its the local webserver that is running this script
    Using the servername and serverport, the return URL is the first
    portion of the URL that buyers will return to after authorizing payment */
    $serverName = $_SERVER['SERVER_NAME'];
    $serverPort = $_SERVER['SERVER_PORT'];
    $url=dirname('http://'.$serverName.':'.$serverPort.$_SERVER['REQUEST_URI']);

[kicken]

You probably don't have to specify it if your just using standard port 80.  I'm guessing that is just an example that shows how to set it in case your using an alternate port.