Binding 2 UDP sockets on same port, connected to different destinations, 1 receives

Posted on 16th Feb 2014 07:03 pm by admin

Hello,
My application wants to send/recv data to 2 different UDP ports on a remote computer, using the same source port.
So I bind to the same local port which works, and connect to the remote IP : port which works as well, but then randomly only one of the two sockets will receive data from the stack, even though packets are arriving on the network for both.

In this code, the local UDP port is always 13398; the first time this code is called, the destination is 192.168.13.45:6970 and the second time it's 192.168.13.45:6972.
What would cause only one of the sockets to receive data afterwards? Also it's randomly the first or the second one that receive data, but once both sockets are binded and connected, only that random one will receive data.

Thanks!

SOCKET serverSock = ::socket(AF_INET, SOCK_DGRAM,IPPROTO_UDP);
int i=1;
if ( setsockopt(serverSock, SOL_SOCKET, SO_REUSEADDR, (char *)&i, sizeof(i)) != 0 ) {
logger.warn(_T("Could not set SO_REUSEADDR: %s"), GetWSATextError(WSAGetLastError()));
}

SOCKADDR_IN saServer, dest;
memset(&saServer,0,sizeof(saServer));
saServer.sin_family = AF_INET;
saServer.sin_addr.s_addr = INADDR_ANY; // Since this is a server, any address will do
saServer.sin_port = htons(m_manager->GetLocalUDPPort()); // Convert int to a value for the port field
int ret = bind(serverSock, (struct sockaddr *) &saServer, sizeof(saServer));
if (ret != 0) {
logger.warn(_T("Could not bind to udp port 1: %d, %s"), m_manager->GetLocalUDPPort(), GetWSATextError(WSAGetLastError()));
return false;
}

memset(&dest,0,sizeof(dest));
dest.sin_family=AF_INET;
dest.sin_addr.s_addr=m_deviceIP;
dest.sin_port = htons(m_devicePort1);
ret = connect(serverSock, (sockaddr *) &dest, sizeof(dest));
if (ret != 0) {
logger.warn(_T("Failed to connect to udp 1: %s:%d, %s"), inet_ntoa(dest.sin_addr), m_devicePort1, GetWSATextError(WSAGetLastError()));
return false;
}

Your Answer:

Login to answer

Other forums

simple php table loop
Hi all,

I've the following code

<?php // Create category options

Dynamic memory problem
Hey,

At the beginning of my code, I have this line:

Shape* gShape = 0;

Looking for help on using joining mysql tables and php....
Does anyone have any good links to references on how to pull mysql data, through joining tables and

How to make a input/output field with multiple lines
Hello.
I put a input/output field on the screen but I could not change height of it. I need to

GIS appliction help
I found some tutorials in the internet to develop a map application I don't want to use google maps

Please Help my PHP Dating Function.
Hi everyone!

Well here is my code that displays this:

It works wonderful.

Database connection failure
Hello All,

I am trying to create new connection to Oracle DB 10.1,
I could not see a

how to get different value in second view of webdynpro?
hello guys,

In ABAP webdynpro I am trying to create one application having two views.

Table Control
Hi Guru's,

I've created a Module pool program, which contains the Table Control.

PHP Directory Listing Not working
Hey Guys,

I need help, I tried a ton of directory listing scripts and they all don't work. Al