Dumping screen contents (front buffer?) at specific time

[Roger WANG]

Hello list,

I have to dump the screen contents (and write to an image file later) at
specific time (say 200.0001 seconds later in milliseconds
resolution). What's the suggested way to do this? Do I have to do it in
the (Intel) driver level? Which piece of code should I look into?

Thanks in advance.

-- 
Roger WANG