anchor.diff:  
   
   %% API
  --export([generate_file_id/0, create_test_file/3, update_test_file/3,
  -    remove_test_file/4, verify_test_file/4, verify_storage_on_all_nodes/1]).
  +-export([generate_file_id/0, create_test_file/3, read_test_file/3,
  +    update_test_file/3, remove_test_file/4, verify_storage_on_all_nodes/1]).
  +
  +%% exported for RPC
  +-export([verify_test_file/4]).
  +
   
   -define(TEST_FILE_NAME_LEN, application:get_env(?APP_NAME,
       storage_test_file_name_size, 32)).
  
positive.code:     end.
  
  %%%===================================================================
  %%% Internal functions
  %%%===================================================================
  
  %%--------------------------------------------------------------------
  %% @private
  %% @doc
  %% Returns content of storage test file.
  %% @end
  %%--------------------------------------------------------------------
  -spec read_test_file(helpers:helper(), helpers:user_ctx(), helpers:file_id()) ->
      Content :: binary().
  read_test_file(Helper, UserCtx, FileId) ->
      Handle = helpers:get_helper_handle(Helper, UserCtx),
      {ok, FileHandle} = helpers:open(Handle, FileId, read),
      {ok, Content} = helpers:read(FileHandle, 0, ?TEST_FILE_CONTENT_LEN),
      ok = helpers:release(FileHandle),
      Content.
  
  %%--------------------------------------------------------------------
  %% @private
  
negative.code: 
  %%--------------------------------------------------------------------
  %% @doc
  %% Returns content of storage test file.
  %% @end
  %%--------------------------------------------------------------------
  -spec read_test_file(helpers:helper(), helpers:user_ctx(), helpers:file_id()) ->
      Content :: binary().
  read_test_file(Helper, UserCtx, FileId) ->
      Handle = helpers:get_helper_handle(Helper, UserCtx),
      {ok, FileHandle} = helpers:open(Handle, FileId, read),
      {ok, Content} = helpers:read(FileHandle, 0, ?TEST_FILE_CONTENT_LEN),
      ok = helpers:release(FileHandle),
      Content.
  
  %%--------------------------------------------------------------------
  %% @doc
  