Autodetect CD

[Reginald Johnson <reginald johnson cox net>]

Hello,
   I'm trying to make my autodetect CD insertions.  I'm using C, GTK, 
and Gnome on a Fedora system, but I don't think the distribution should 
matter in this instance.  What signal do I have to capture from Gnome to 
tell my app to check to see if a new CD has been inserted in the drive? 
Or is there another technique I should be using?
   Thanks in advance.

Reginald Johnson