status.i4.v = wn_circle(x.r4.r, y.r4.r, radius.i4.r)

	status.i4.v = wn_circle_c(x.r4.v, y.r4.v, radius.i4.v)

	This routine draws a circle at virtual coordinates X,Y in a graphical
	window specified by a previous call to wn_active(_c).  wn_view(_c)
	and wn_world(_c) must also be called before calling this routine.
	The color of the circle is determined by the most recent call to
	wn_color(_c).  The width of an unfilled circle is determined by
	the most recent call to wn_border_width_c.  Whether the circle is
	filled or not is determined by the most recent call to

	x, y		real world coordinates of the circle
	radius		radius of the circle in pixels

	This function returns ACNET status values as follows:

	OK			success
	CBS_NOSETUP		an active window has not been established

	This function requires the following include files:

	cbslib_h, acnet_errors_h

	Related functions:

	wn_color(_c), wn_user_defined_color_c, wn_read_user_defined_color,
	wn_fill_mode(_c), wn_border_width_c, wn_flush, intro_graphics_windows

	C/C++ usage:

	int	status;
	int	radius = 5;
	float	x = 3.0;
	float	y = 3.0;

	status = wn_circle_c(x,y,radius);