anchor.diff:  %% @spec put(state(), BKey :: riak_object:bkey(), Val :: binary()) ->
   %%         ok | {error, Reason :: term()}
   %% @doc Store Val under Bkey
  -put(State,BKey,Val) ->       
  +put(State,BKey,Val) ->
       File = location(State,BKey),
       case filelib:ensure_dir(File) of
           ok -> atomic_write(State, File, Val);
  
positive.code: %% "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
  %% KIND, either express or implied.  See the License for the
  %% specific language governing permissions and limitations
  %% under the License.    
  
  % @doc riak_fs_backend is a simple filesystem storage system.
  
  
negative.code: %%       ok | {error, Reason :: term()}
  %% @doc store a atomic value to disk. Write to temp file and rename to
  %%       normal path.
  atomic_write(_State, File, Val) ->
      FakeFile = File ++ ".tmpwrite",
      case file:write_file(FakeFile, Val) of
          ok ->
  