HRESULT GetGDISurface(LPDIRECTDRAWSURFACE FAR * lplpGDIDDSSurface);
Retrieves the DirectDrawSurface object that currently represents the surface memory that GDI is treating as the primary surface.
·Returns DD_OK if successful, or one of the following error values otherwise:
lplpGDIDDSSurface
Address of a DirectDrawSurface pointer to the DirectDrawSurface object that currently controls GDI's primary surface memory.