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CSockets for Client-Server operation

Posted on 2003-11-20
Last Modified: 2013-11-20
I am using CSockets for a Client-Server model.( both sides must be able to send and receive )

On the Client side I have a class that extends the CSocket class and overrides the following methods:
       void OnConnect(int nErrorCode);
       void OnSend(int nErrorCode);
       void OnReceive(int nErrorCode);
       void OnClose(int nErrorCode);
       void OnAccept(int nErrorCode);

On the Server side I have a class that extends the CSocket class and overrides the following methods:
       void OnSend(int nErrorCode);
       void OnReceive(int nErrorCode);
       void OnClose(int nErrorCode);
       void OnAccept(int nErrorCode);

I can send data to the Server. But I also wish to receive something at the Client side from the server. Is it necessary for me to do a Listen on the client side ? I tried this but then I can never connect at all to the Server. I dont think I need to even add any code to the OnAccept() function on my client to spawn of another socket. My OnReceive() should be able to handle it in the context of the current socket.  But it doesnt seem to work. What am I doing wrong ?

Note that  sockets on both sides are created as :

BOOL Val = clientSocket.Create(clientPort);
BOOL Val = mySocket.Create(serverPort);

Help !
Question by:prakash_gs
LVL 48

Expert Comment

ID: 9786483
You need to have listening socket in the server. For each new connection you should create socket which talks with connected client.
Client application should have only one socket which both sends and receives data.

Listening socket - OnAccept: create client socket which sends and receives data.

Client - socket which sends and receives data.

Check out MFC Sample CHATSRVR.

LVL 48

Expert Comment

ID: 9786515

Expert Comment

ID: 9805512
no you don't need a listening socket on the client end, you could but you don't have to.

you should have listen and accepting socket at the server end.
the listen socket waits incoming connections and you accpt it like this

 AcceptSocket.accept ( listenSocket )

on the client end you would only have a clientSocket
and start Connect()
once the connection is established you can send and receive data on both ends..

are you using Async or nonAsync sockets ?..


Author Comment

ID: 9809086
i figured out my problem.
I wasnt doing a send on the spawned socket that is created on the server on the OnAccept().Instead I was trying to directly send using my parent Server socket. So there ends my travails for now.(I hope...)
Thank you guys.

Accepted Solution

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ID: 11984794
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