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

Clean URLs
Hi I was wandering if anyone has ever implemented URLs on their PHP run website using URLS like wiki

Varible in trigger - refering to correct schema
Hello

Im having some issues with my trigger.
What I want to do is call opon a differ

Hyperlink in PHP to MySQL record
Hello,

I am having trouble as i am new to php. I have connected to the database and I have di

highlighting search terms
well, I started this in the regular PHP section, but it no longer fits there. Suffice it to say, I'm

Sequre login with cookies.
I want to build secure login with cookies. I just want your ideas about this, your suggestions. What

Cursor statement failed with errors
Following statement failed with the errors.

cursor proj_cursor1 is (select projectID from

How to show a complete textarea ??
I enter Client Case Notes notes in a textarea field on a PHP form. The field is 5 rows deep and 70 c

how to query data from website using VC?
I want to query some datum from a website,so I need a program to read data from a .csv file, and ass

Storing/displaying image urls in a database?
Hi
Basically I have the following scenario:
User chooses picture from list. Picture info is ad

wav to mp3 + goDaddy
I need to convert wav files to mp3s. From what I have found so far one way to do it is to have my PH