Winsock Array with data arriving simultaneously stops sending data to clients

1
votes

I've been searching online for days now and I can't find anyone who has this same problem with the VB6 Winsock. So here's my problem, I have a server with two winsocks in an array. I then have two clients each with one winsock control. Now the I have it set up is that the server first sends data to client A. Then client A receives that data and sends its own data back to the server. Then the server sends data to client B, once client B receives the data, it sends its own data back to the server. So data is being sent from a client to the server, then from the server to another client, then back to the server, and then on to another client. I did it this way because when I tried doing it the way I really want it to work, I was having problems. So I had to set it up this way in order to ensure that only one client is sending data to the server at any one time. This process works perfectly, however I want it to work in a different way, since as you can image, the more clients there are, the longer the delay in data transfer between each client and the server.

So what I really want to do, which I can't get to work, is have the clients send and receive data to the server whenever they want. That is, client A sends data to the server, and then the server sends data back, all while client B is doing the same thing. When I do this, even though I have a winsock array on the server, I run into a problem. When client A first connects, it begins sending and receiving data to the server. But once client B connects to the server, all communication between client A and the server stops, and only client B sends and receives data to the server. Now I've done some tests and client A remains connected to the server the whole time. But for some reason, it seems that if two clients send data to the server simultaneously, only one data arrival event fires, even though each winsock is on a different port. I have not installed VB6 SP6 yet, as I'm not sure this will fix the problem.

So I really do hope someone will read this and explain to me what it is that I'm not understanding or what it is that I'm doing wrong.

2
vb6client-serverwinsock
could you post the code in which you start listening, as well as the code in which you open the connect, and the code in which you receive and send data? – Hrqls

2 Answers

2
votes

If you search for Microsoft KB articles on the Winsock control you will find a long history of flaws and bug fixes. There is absolutely no reason not to install SP6 before even attempting to use VB6, since a vast number of issues were resolved over time.

Once you've done that (and only then) is it really worth talking about problems of the sort you describe. At least it eliminates a significant number of known problems, and then it might be worth discussing your code.

-3
votes

Are you using none blocking sockets? I guess you should. You should probably create a thread for each incoming connection. So the main loop should act none blocking and create a thread for each incoming connection, that receives the data and sends the answer.