Socket port destination problem

[radeberger]

Hi everybody,

I have an application where two different socket connections run in order to communicate with a machine. Over the first one (UDP) I send a request packet to ask for data and over the other one connection (TCP) I receive the data.
I repeat this procedure two times that is, I request a block of data and when it's finished I request a second one.By the first time it works without problems but by the second time I discovered with wireshark that the request packet is sent to another port (not over the original port). I know I haven't made changes between the first request call and the second one because I have a function where I initialize all connections at the beginning and it works for the first transmission.

Can anyone help me?

Thank you very much

[Duthomhas]

Why are you using UDP? Use TCP both ways.

That should (hopefully) fix your problem.

[radeberger]

Hi,

because that is design requirements...

Hi again,

Now I can describe the problem better

I have a tcp server that wait for data in the recv function after accept. I receive data buffer of 1500 bytes but I don't receive only one buffer. I receive more. The first time the socket receives something port=2000 (so it's right) but the second time and successively port=49154. Something is wrong with the receive function...

AcceptSocket = accept(socketInTCP, NULL, NULL);		 
		 if (AcceptSocket == INVALID_SOCKET)
		 {	 
			
			 printf("Server: WSA:\n");
			
		 }
		 else
		 {   
			 printf("Server: Client Connected!\n");
			 //Receive Packages from Client
			 while(run_tcpserver)
			 {  	bytesRecv = recv(AcceptSocket, recvbuf, sizeof(recvbuf), 0);
				if (bytesRecv > 0)
				{if(ctr1==1)
					{	
						WaitForSingleObject(mutex_req,INFINITE);
						//The first time it receives port = 2000
					}
				 
                                 //the second time and successively port =49154
                                 ctr1=0;
				 ofstream outfile(outputfile, ios::out |ios::ate | ios::binary);//open
				 rcv_data=rcv_data+bytesRecv;
				 cout << "\xd" << rcv_data;
				 
				 outfile.write (var, sizeof(var));
				 outfile.close();
				 memset(recvbuf,0,sizeof(recvbuf));
				 
                                 if(rcv_data==(length_dummy*4))
					{
						ReleaseMutex(mutex_req);
						
					}

have anyone any ideas??

[radeberger]

I think it's a synchronization problem because I use a mutex for the screen and I think something is wrong but I can't see it....