anchor.diff:        real(c_double), intent(in), value :: symprec, angle_tolerance
         integer(c_int) :: spgat_find_primitive
      end function spgat_find_primitive
  -
   
   
      function spg_get_international( symbol, lattice, position, types, num_atom, symprec) bind(c)
  
positive.code: 
           ! Copy C strings to Fortran characters, converting C NULL to Fortran space padded strings
           do i = 1, size(dset_c % international_symbol)
              if(  dset_c % international_symbol(i) == C_NULL_CHAR ) then
                  dset % international_symbol(i:) = ' '
                  exit
              end if
  
negative.code:       real(c_double), intent(in), value :: symprec, angle_tolerance
        integer(c_int) :: spgat_get_schoenflies ! the number corresponding to 'symbol'. 0 on failure
     end function spgat_get_schoenflies
  
  
     function spg_get_pointgroup( symbol, trans_mat, rotations, num_rotations) bind(c)
  