anchor.diff:  	    ok = undo_files(Files),
   	    Modified = lists:map(fun({{OldFileName, NewFileName,_}, _Con})->
   					 [OldFileName, NewFileName] end,Files),
  -	    {reply,{ok, Modified, LogMsg, CurFile}, #state{history=T}}
  +	    {reply,{ok, Modified, LogMsg, CurFile}, State#state{history=T}}
       end;
   handle_call(undo, _From, State=#state{history=History}) ->
       case History of 
  
positive.code: 						 [OldFileName, NewFileName]
  					 end
  				 end,Files),
  	    {reply,{ok, Modified}, #state{history=T}}
      end;
  handle_call(files_to_change, _From, State=#state{history=History}) ->
      case History of 
  
negative.code: %%--------------------------------------------------------------------
  start_undo_server() ->
      process_flag(trap_exit, true),
      gen_server:start_link({local, wrangler_undo_server}, ?MODULE, [], []).
  
  %%-spec(undo_emacs/0::() ->
  %%		 {ok, [filename()], string(), filename()}|{error, string()}).
  undo_emacs() ->
      gen_server:call(wrangler_undo_server, undo_emacs).
     
  %%-spec(undo/0::() ->{ok, [filename()]}|{error, string()}).
  undo() ->
      gen_server:call(wrangler_undo_server, undo).
     
  
  %%This is added to make Wrangler work with clearcase.
  %%-spec(files_to_change/0::() ->
  %%	     {ok, [filename()]}).
  files_to_change() ->
      gen_server:call(wrangler_undo_server, files_to_change).
     
  
  %%-spec(add_to_history/1::({filename(), filename(), binary()}) -> ok).
  add_to_history({Files, LogMsg, CurFile})->
      gen_server:cast(wrangler_undo_server, {add, {Files, LogMsg, CurFile}}).
  
  %%====================================================================
  %% gen_server callbacks
  %%====================================================================
  