How to capture packets in localhost between two ports

Question

I have two applications communicating on same machine (localhost) using socket. If application are on different machine I can use Wireshark. But how to capture packets on same machine.

I do not know on which port number application are communicating. Because I am using library calls and do not know lower level details.

We are having our application on Ubuntu and Windows XP.

Answer 1

On Linux you can use netstat to determine the ports that your application are using. Then you can use Wireshark to capture on the loopback interface (just enter your own IP address if 127.0.0.1 dont work).

Refer to: https://stackoverflow.com/questions/1566234/ for capturing on Windows.