window_id.i4.v = window_topmost_c(row.i4.v, column.i4.v)

	This routine returns the window ID of the topmost window at
	the screen character location indicated by "row" and "column" in
	the background (or root) window.

	row, column	character position in full screen coordinates

	This function returns status values as follows:

	ID of exposed window at the requested location

	This function requires the following include files:


	Related functions:

	window_to_front, intro_tv_windows

	C/C++ usage:

	int	window_id;
	int	row = 1;
	int	column = 1;

	window_id = window_topmost_c(row,column);