BLEFIX ( body, nblend, blends, faces, edges, error, err_ed, topol, ifail )
==========================================================================

  Fix blends in a body.

Receives:
  KI_tag_body              *body           --- body to fix blends in

Returns:
  KI_int_nitems            *nblend         --- number of blend faces
 <KI_tag_list_face>        *blends         --- list of created blend faces
 <KI_tag_list_list>        *faces          --- list of underlying faces
 <KI_tag_list_int>         *edges          --- list of (dead) tags of edges
  KI_cod_blcc              *error          --- first error from blending body
 <KI_tag_edge>             *err_ed         --- edge associated with error
 <KI_tag_topology>         *topol          --- topology associated with error
  KI_cod_error             *ifail          --- failure code

Specific errors:
  KI_cant_fix_blends        could not fix blends in body
  KI_general_body           general body

Description:
  Any edges of the  body which have blend attributes are changed into  full faces
  with the appropriate blending surface geometry.

  BLEFIX returns the number of  created blend faces,  and three parallel lists
  containing the created blend face tags, lists of tags of the associated
  underlying faces of the blend faces, and the tags of the edges which were
  blended to produce this set of blend faces.

  'blends' will contain 'nblend'  faces, which are the created blend faces.

  'faces' will  contain 'nblend' lists of faces. These are the underlying faces
  associated with the blends. The underlying faces of a blend are the faces whose
  geometry determines the blend surface geometry. Some of the face tags may be
  null. This occurs if there is no face in the final body with the appropriate
  surface geometry, which can be the case if a face has been entirely blended
  away, or for the cliff side of a cliffedge blend.

  'edges' will  contain 'nblend' integers. These integers are the (dead) tags of
  the edges which were blended to produce this set of blends. The same value
  may occur several times in this list if , for example, a blend has overflowed,
  since all the corresponding faces in 'blends' were caused by the same blend
  attribute.


  Note that  the number  of tags in  each list of underlying faces is
  the number  of original   underlying faces  for  that  blend, but that the tags
  returned are  those of the faces after the blend has been fixed, and so some of
  them may be null (if the face has been completely blended out).

  If  the attempt to fix  the blend fails due to an error which would be detected
  by BLECHK, the  edge associated with the  error will be returned as 'err_ed'
  and 'error' and 'topol'   are the same as would be returned if  BLECHK was
  called with 'err_ed'. These can be used to locate the  reason for  failure to
  fix the blend. Note  that  only the  first  error  will  be returned. If no
  errors are found 'error' will be zero and 'err_ed' and 'topol' will be null
  tags.

  Note  that blends created with the property BLECDF will not be fixed.

  This function is not supported for general bodies.