fill_hook_table ()
{
  set_pointers (ulong access_key)
  {
    set_hook_table (access_key, &cmd),
    {
      cmd = {
              free : destroy_tree_node,
              move : move_tree_node
            }
    };
  }

  set_hook_table (&cmd),
  {
    cmd = {
            st : tree_node,
            fp : set_pointers
          }
  };
}