[cairo] Erasing A Line

[Allen]

Hello,

I'm a totally newbie to Cairo but I FAR prefer it to the .Net <blah>.

Could someone possibly tell me how to erase a line once I've drawn it?  
I've tried to determine the "background" color of my Drawing area widget 
- it's not white but WILL be a picture eventually - and the Cairo 
context info does not show me how to get the background color before 
drawing on it.

Eventually, I will be drawing on a Picture but the line must be erasable 
as it's being drawn because the user is to be allowed to click on a 
"spot", drag to another "spot", and release.  While they are "dragging" 
the cursor (mouse pointer) around, I need to have the line erased & 
redrawn dynamically.

Would y'all please help me?

Thanks so much.  I really appreciate this.

-- 
Sincerely, Allen

Gene Allen Saucier, Jr
Software Engineer
EDO-CAS, Inc
Madison Research Park, Bld 111
111 Research Blvd
Madison, AL  35758
"...As for I and my house, we shall follow the Lord"  Joshua 24:15