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

Error when call dll from oracle
Hi all, please help me!

I have dll write C language, I want call it from oracle procedur

help with multi-update
Now sure how to ask this really....
10g database if that matters.

I have a customer

Simultaneous select/update/insert
Hi

How would I need to go about when 2 users update a single row simultaneous? And how would

Printer configuration
Hi All,
Suppose one of the user deleted the printer settings unfortunatly ,then what is the pro

Email logic not working
I would like to send an email using the php email() function then if it does execute i.e sends i wou

php require help needed
Ok i tried to use the search funtion but the word require is everywhere.

i'm really new to cr

Problem displaying "scraped" XML data
I'm basicly having trouble displaying XML data scraped from an URL using cURL.

What the code

While Problem
i am having a problem with a while statement here is the code
Code: [Select]<?php
sess

Comparing two dates
Hi Guys
I have two dates I want to compare. Below is my current implementation. The problem with

COOIS - Saving Object Overview WIP Status layouts
COOIS - Would like to be able to save the layout of an Object Overview - WIP Status report. There i