anchor.diff:  handle_batch_start({error, already_deleting}) ->
       output("Error: A garbage collection batch"
              " is already in progress."),
  +    error;
  +handle_batch_start({error, already_paused}) ->
  +    output("The garbage collection daemon was already paused."),
       error.
   
   handle_status({ok, {State, Details}}) ->
  
positive.code:             Code
          catch
              Type:Reason ->
                  io:format("~s failed:~n  ~p:~p~n",
                            [Description, Type, Reason]),
                  error
          end).
  
  
negative.code: handle_batch_cancellation(ok) ->
      output("The garbage collection batch was canceled.");
  handle_batch_cancellation({error, no_batch}) ->
      output("No garbage collection batch was running."),
      error.
  
  handle_pause(ok) ->
      output("The garbage collection daemon was paused.");
  handle_pause({error, already_paused}) ->
      output("The garbage collection daemon was already paused."),
      error.
  
  handle_resumption(ok) ->
      output("The garbage collection daemon was resumed.");
  handle_resumption({error, not_paused}) ->
      output("The garbage collection daemon was not paused."),
      error.
  
  output(Output) ->
      io:format(Output ++ "~n").
  