I have just recently switched to linux and found it is really wonderful! I really don't want to use windows any more. But the only thing that make me have to keep switching between linux and windows is a chatting software called OICQ(just like ICQ, very famous in my country)

It doesn't have a linux:-(. So I decide to write a small program that allows me to talk with the ones using OICQ. However, I am also a beginner in network programming. I have only written a small chat program that works in a LAN before. I don't know the port that software is using and maybe I need something else as well to implement this.

I will be very appreciate if someone could give some advice.

linux icq clients - http://avenir.dhs.org/icq/linux.html

Even more linux ICQ clients...
http://freshmeat.net/browse/23/?filt...y_percent+DESC

I'd recommend gaim and LICQ.

If you want to get into network programming, I'd suggest going through gcc docs, 'make' docs, get a good editor you like. Read the Steven's "unix network programming" http://shop.barnesandnoble.com/textb...sbn=013490012x
, sock-faq http://www.developerweb.net/sock-faq/ for starters.