MSC: short _rectangle( short ctl, short x1, short y1,

				short x2, short y2 )

	MSC: short far _rectangle_w( short control, double wx1,
					double wy1, double wx2, double wy2 )

	MSC: short far _rectangle_wxy( short control,
		struct _wxycoord far *pwxy1, struct _wxycoord far *pwxy2 )


	- prototype in graph.h

	- (x1,y1) upper left corner of rectangle
	- (x2,y2) lower right corner of rectangle
	- ctl	= _GFILLINTERIOR	fill rect. with current color and mask
		= _GBORDER		don't fill rectangle

	- returns nonzero on success; zero otherwise