I have created a simple caller ID application that simply listens to the modem and displays who is calling my phone line, it also displays the number of the person calling, and if that number matches up to my contact on file I displays the their name. Now I would like to take this to another level, and have it detect someone calling when I am online using dialup(which is rare but happens). How would I go about setting that up?

Has anyone done this, that can guide me in the right direction? Does anyone have any source code that I can go through to find what I need.

Any help is appreciated.