IDSOFF ( face, surfac, revers, ifail )
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  Identify surface of face

    Can be called from the GO.

Receives:
  KI_tag_face              *face           ---  face

Returns:
  KI_tag_surface           *surfac         --- surface
  KI_cod_logical           *revers         --- true if face normal
                                           --- opposed to surface normal
  KI_cod_error             *ifail          --- failure indicator

Specific errors:
  KI_missing_geom           The given face has no associated surface

Description:
  The surface associated with the given face is returned.

  'revers' is set to true if the face normal is anti-parallel to the surface
  normal. If the direction of the face normal is parallel to the surface
  normal, 'revers' is set to false.