OUBSPC ( bc, ctrl, dim, order, nctrl, knots, props, nprops, ifail )
===================================================================

  Output B-curve in B-spline form

Receives:
  KI_tag_b_curve           *bc             --- B-curve

Returns:
  KI_tag_list_dbl          *ctrl           --- control points
  KI_int_dimension         *dim            --- dimension of control points
  KI_int_order             *order          --- order of curve
  KI_int_nitems            *nctrl          --- number of control points
  KI_tag_list_dbl          *knots          --- knot values
 <KI_tag_list_int>         *props          --- list of curve properties
 <KI_int_nitems>           *nprops         --- number of curve properties
  KI_cod_error             *ifail          --- failure indicator


Description:
  This function outputs a B-curve in B-spline form.

  Dimension of control points 'dim':
  . For rational curves 'dim'=4.
  . For non-rational curves 'dim'=3.

  Order of the curve 'order':
  . The order of the curve = degree + 1.
  . The minimum order is 2.

  Control points 'ctrl':
  . This is a real list containing 'nctrl' vectors of dimension 'dim'.
  . For non-rational curves, the vectors are points in 3-space and are
    returned [x0,y0,z0,x1,y1,z1,...].
  . For rational curves each vector contains a point in 3-space followed by a
    weight for the point. The points are returned [x0,y0,z0,w0,x1,y1,z1,w1,...].
    The weights are positive.

  Number of control points 'nctrl':
  . For non-periodic curves 'nctrl' >= 'order'.
  . For periodic curves 'nctrl' >= 3.

  Knot vector 'knots':
  . The knot values form a non-decreasing sequence.
  . For non-periodic curves there are ('nctrl' + 'order') knot values.
  . For periodic curves there are ('nctrl' + 1) knot values.
  . The knot values follow the rules described in CRBSPC.

  Properties list 'props':
    At most one property token will be returned -
    . PAPRPE - the curve is periodic. If this token is not present then the
      curve is not periodic.

  Number of properties 'nprops':
  . Gives the number of properties in the 'props' array.
  . There is only one property that could apply (periodicity) and so 'nprops'
    is always either 0 or 1.