SHAREN ( body, nopts, opts, ngeom, ifail )
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  Shares underlying geometry of a body

Receives:
  KI_tag_body              *body           --- body on which to attempt sharing
 <KI_int_nitems>           *nopts          --- number of options in opts
  KI_cod_shop               opts[nopts]    --- sharing control options

Returns:
 <KI_int_nitems>           *ngeom          --- number of geometries removed
  KI_cod_error             *ifail          --- failure code


Description:
  This function attempts to reduce the size of a part. It is primarily intended
  for use on pre-V5 bodies.

  With no options supplied, the function will search through all the surfaces
  and curves in the body removing any duplicates it finds.

  Duplicates are curves or surfaces of the same type that are spatially and
  parametrically coincident. The function is designed only to spot where copies
  have been made (either internally or by the user).

  The option accepted is:

  SHOPIC: only process intersection curves

  The option SHOPIC limits the search to edge curves which are intersection
  curves. In pre-V5 bodies a high proportion of the cases where sharing is
  possible occur with these edge curves.