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;
}

No comments posted yet

Your Answer:

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

import table with dependency
Hi

What is the best way to import table back which has dependency?

SQL> cre

help with php
It's not displaying or pulling anything out of the database.


Code: <html><

ScriptResource.axd gives an error on fresh install of ASP.NET Ajax 1.0
Hello,I have a fresh install of Microsoft ASP.NET Ajax 1.0. When I create an Ajax enabled website in

How to show the difference between two data field in a database with php.
Hello php gurus,

how r u all... i'm not so well facing a typical problem please help me...<

Show message after entering data
Hello Colleagues

I would like to display messages after entering the data example: "
dat

how to load a Sys file with system load and call images?
normally you need register the module as a service with CreateService, and start the service

Is there a way to override built in php functions without APD?
I am trying to use the
rename_function()
override_function()
options that are built into

PHP friend keyword equivalent
is there a PHP equivalent for the C++ friend keyword?

Multidimensional $_POST
Hello

How to get a single array from array of array (2 - dimension).
For example I have a

apart from cron
I need to run a php file every one hour. Is there any other solution apart from cron job?

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