Get Local IP-Address using Boost.Asio
- by MOnsDaR
Hey,
I'm currently searching for a portable way of getting the local IP-addresses. Because I'm using Boost anyway I thought it would be a good idea to use Boost.Asio for this task.
There are serveral examples on the net which should do the trick. Examples:
Official Boost.Asio Documentation
Some Asian Page
I tried both codes with just slight modifications. The Code on Boost.Doc was changed to not resolve "www.boost.org" but "localhost" or my hostname instead. For getting the hostname I used boost::asio::ip::host_name() or typed it directly as a string.
Additionally I wrote my own code which was a merge of the above examples and my (little) knowledge I gathered from the Boost Documentation and other examples.
All the sources worked, but they did just return the following IP:
127.0.1.1 (Thats not a typo, its .1.1 at the end)
I run and compiled the code on Ubuntu 9.10 with GCC 4.4.1
A colleague tried the same code on his machine and got
127.0.0.2 (Not a typo too...)
He compiled and run on Suse 11.0 with GCC 4.4.1 (I'm not 100% sure)
I don't know if it is possible to change the localhost (127.0.0.1), but I know that neither me or my colleague did it. ifconfig says loopback uses 127.0.0.1. ifconfig also finds the public IP I am searching for (141.200.182.30 in my case, subnet is 255.255.0.0)
So is this a Linux-issue and the code is not as portable as I thought? Do I have to change something else or is Boost.Asio not working as a solution for my problem at all?
I know there are much questions about similar topics on Stackoverflow and other pages, but I cannot find information which is useful in my case. If you got useful links, it would be nice if you could point me to it.
Thanks in advance,
MOnsDaR
PS:
Here is the modified code I used from Boost.Doc:
#include <boost/asio.hpp>
using boost::asio::ip::tcp;
boost::asio::io_service io_service;
tcp::resolver resolver(io_service);
tcp::resolver::query query(boost::asio::ip::host_name(), "");
tcp::resolver::iterator iter = resolver.resolve(query);
tcp::resolver::iterator end; // End marker.
while (iter != end)
{
tcp::endpoint ep = *iter++;
std::cout << ep << std::endl;
}
