anchor.diff:  -spec(compact_put(atom(), KeyBin::binary(), ValueBin::binary()) ->
                ok | {error, any()}).
   compact_put(Id, KeyBin, ValueBin) ->
  -    gen_server:call(Id, {compact_put, KeyBin, ValueBin}).
  +    gen_server:call(Id, {compact_put, KeyBin, ValueBin}, ?DEF_TIMEOUT).
   
   
   %% @doc get database file path for calculating disk size.
  
positive.code:     error_logger:info_msg("~p,~p,~p,~p~n",
                            [{module, ?MODULE_STRING}, {function, "stop/1"},
                             {line, ?LINE}, {body, Id}]),
      gen_server:call(Id, stop).
  
  
  %%--------------------------------------------------------------------
  
negative.code: -spec(first(atom()) ->
               {ok, list()} | {error, any()}).
  first(Id) ->
      gen_server:call(Id, {first}, ?DEF_TIMEOUT).
  
  
  %% Retrieve status from backend-db.
  