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

Sending UDP Raw socket
I truly need help on this. I am trying to write a test program that simulate a network environment

Check if another session of the page is running?
I want to keep people from opening multiple tabs, or sessions of my Facebook app. Is it possible to

Fetching array then reversing it
Hi, I have a simple problem, I'll try to explain it as best I can:
News entries in my database ar

how do i display data on a page from mysql
1 - do i use this code at the top of each of my page i wish to only alow access if there as been a s

why preg_match_all does not return the number of matches
My regex looks like

X[^x{4e00}-x{9fa5}]*Y

(where X and Y are two Chinese characters)

Can't seem to capture a variable in a chained select
I'm *this* close to having a chained select running but for some reason it doesn't seem to be pickin

Having a problem get the selected item from a drop down menu
I have been looking at this for days now.

I have a drop down menu that get it's values from a

Help With editting and deleting form
Hallo !!

So look at this image :

http://img194.imageshack.us/img194/8272/snapshot5f.pn

PHP and MySQL on intranet?
Is it possible to use both these on an intranet network?

Adding to an Int row in db
Hi, i have a database which houses all of the users of my site. One of the columns is for points whi