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.

Did you know?Explore Trending and Topic pages for more stories like this.
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;
}
No comments posted yet

Your Answer:

Login to answer
202 Like 12 Dislike
Previous forums Next forums
Other forums

creating a 1 to 100 in a table
hi guys I am a newb in php need some help.

I have a table with 1 column and 100 rows and in

need help in update query
hi
i have a dynamic form. i need help in how can i use update query when values from dynamic for

Check Date/Time in PHP
What I need the code to check is that $reQuest is 24 hours in the past then return a time based on h

How do I send data using an html link
Hi

If I have
<a href="main_file.php">

How do I send data t

question about stripslashes and real_escape_string
im cleaning up an old app that I wrote fixing some of the vulernabilities from attacks.

I hav

Wordpress IE issue
So I am trying to add the background shadow to my wordpress page. It works fine in Firefox but does

change text color with a jQuery code
Hihow can I change the text in a asp:TextBox to a different color when I start typing using jQuery?I

Check premium expire
Hi,

I am making a simple file hosting site and want to check if users premium subscriptions h

Add code to enable passing of checkbox variable on login
Ok, I have a login page, but want to add a checkbox that when checked and successful login is made i

some query on multilingual website
Hi all,

Which is the simplest and easiest method to make a website multilingual,
is it put

Sign up to write
Sign up now if you have flare of writing..
Login   |   Register
Follow Us
Indyaspeak @ Facebook Indyaspeak @ Twitter Indyaspeak @ Pinterest RSS



Play Free Quiz and Win Cash