gdk-window-update-area (window)

window -- a gdk-window object

The update cairo-region-t area for window.

Transfers ownership of the update area from window to the caller of the function. That is, after calling this function, window will no longer have an invalid/dirty region; the update area is removed from window and handed to you. If a window has no update area, the function gdk-window-update-area returns nil. You are responsible for calling the function cairo-region-destroy on the returned region if it is non-nil.