PHP technique to query the APNs Feedback Server

Question

Can someone clarify what the APNs (Apple Push Notification) wants as far as how you query it?

The docs say it starts sending as soon as the connection is made. Does

Answer 1

That code looks right however you need to loop and check for end of stream in order to read all the device codes.

 while (!feof($apns)) {
        $devcon = fread($apns, 38);
 }

However my problem is the actual unpacking of the data. Does anyone know how to unpack the binary data which you've just read to get the actual device ID (as string) along with the timestamp etc?