Does it work to make a screenshot function in blitz
it would be good to know.
If you are running something in 'windowed mode' you can press Alt+PrintScreen to copy the window into the clipboard.
Using the Printscreen key isn't a "screenshot function in Blitz," what he asked for. Using SaveBuffer (as DarkEagle pointed out) is what you want.
I personally use DarkEagle's method, and I even implented it in "The Fairy Tale"... I've only configured it to the "F10" key, but that's the most important diffrence :)