anchor.diff:  handle_info({'DOWN', MonitorRef, process, _Object, _Info}, #state{sessions=Sessions}=State) ->
       NewSessions = remove_session_from_list(MonitorRef,Sessions),
       shutdown_if_done(NewSessions,State);
  -handle_info(timeout, #state{id = Id} = State) ->
  -    ok = tts_user_mgr:user_wants_to_shutdown(Id),
  +handle_info(timeout, State) ->
  +    ok = tts_user_mgr:user_wants_to_shutdown(self()),
       {noreply,State,5000};
   handle_info(_Info, State) ->
   	{noreply, State}.
  
positive.code: -include("tts.hrl").
  
  %% API.
  -export([start_link/1]).
  -export([set_user_info/2]).
  -export([get_user_info/1]).
  -export([get_credential_list/1]).
  
negative.code: 
  %% gen_server.
  
  init([]) ->
  	{ok, #state{}, 5000}.
  
  handle_call({set_user_info,UserInfo}, _From, State) ->
      #{ uid := Uid,
         uidNumber := UidNumber,
         gidNumber := GidNumber,
         homeDirectory := Dir,
         user_ids := UserIds
       } = UserInfo,
      NewState = State#state{ uid = Uid,
                              uidNumber = UidNumber,
                              gidNumber = GidNumber,
                              homeDirectory =Dir,
                              user_ids = UserIds
                            }, 
  
      {reply, ok, NewState};
  handle_call(get_user_info, _From, State) ->
      #state{ uid = Uid,
              uidNumber = UidNumber,
              gidNumber = GidNumber,
              homeDirectory =Dir,
              user_ids = UserIds
            } = State, 
  
      UserInfo = #{ uid => Uid,
         uidNumber => UidNumber,
         gidNumber => GidNumber,
         homeDirectory => Dir,
         user_ids => UserIds
       },
      {reply, {ok, UserInfo}, State};
  handle_call(get_credential_list, _From, #state{credentials=Creds}=State) ->
  