Draws a circle with its middle point at (x, y). The circle starts and ends at position (x+radius, y). If this function is called outside a path it will start a new path. If it is called within a path it will add the circle as a subpath. If the last drawing operation does not end in point (x+radius, y) then there will be a gap in the path.
Resource identifier of the postscript file as returned by ps_new.
The x-coordinate of the circle's middle point.
The y-coordinate of the circle's middle point.
The radius of the circle
Returns true on success or false on failure.