My goal is to create a real-time chat similar to the Facebook chat, from scratch. I want to store all the messages on a database table (MySQL) and every time a new message is sent by a user, if the receiver is connected then a request will be sent to the receiver's browser and the message will appear on the chat window.
I don't want to have the client to check if a new message for the user was sent, but I want the server to send the request to the client's browser.
I know that this can be achieved using the Comet technique (I saw this stackoverflow question) but I am not able to find a good guide on how to implement this for this certain problem.
I want to use php and javascript and as less extra software or frameworks as possible.
I use WAMPServer and I have Windows.
If you know a good guide or tutorial or can provide any guidelines on how I could achieve what I want, it would be very helpful.