anchor.diff:      gen_server:call(name(Context), get_modules_status).
   
   
  +%% @doc Return the pid of a running module
  +whereis(Module, Context) ->
  +    gen_server:call(name(Context), {whereis, Module}).
  +
  +
   %% @doc Return the list of all modules in the database.
   %% @spec all(#context{}) -> [ atom() ]
   all(Context) ->
  
positive.code:     active_dir/1,
      get_modules/1,
      get_modules_status/1,
      all/1,
      scan/1,
      prio/1,
  
negative.code: %% @doc Return all running modules and their status
  handle_call(get_modules_status, _From, State) ->
      {reply, z_supervisor:which_children(State#state.sup), State};
  
  %% @doc Return the pid of a running module
  handle_call({whereis, Module}, _From, State) ->
      Running = proplists:get_value(running, z_supervisor:which_children(State#state.sup)),
      Ret = case lists:keysearch(Module, 1, Running) of
          {value, {Module, _, Pid, _}} -> {ok, Pid};
          false -> {error, enoent}
      end,
      {reply, Ret, State};
  
  %% @doc Trap unknown calls
  handle_call(Message, _From, State) ->
  