fix service

apps/modbus/src/modbus_logger.erl

@@ -48,9 +48,13 @@ start_link(FileName) when is_list(FileName) ->
     {stop, Reason :: term()} | ignore).
 init([FileName]) ->
     ensure_dir(filename:dirname(FileName)),
-    {ok, IoDevice} = file:open(FileName, [append, binary]),
-
-    {ok, #state{file = IoDevice, file_name = FileName}}.
+    case file:open(FileName, [append, binary]) of
+        {ok, IoDevice} ->
+            {ok, #state{file = IoDevice, file_name = FileName}};
+        {error, Reason} ->
+            lager:warning("[modbus_logger] create log file: ~p, error: ~p", [FileName, Reason]),
+            ignore
+    end.
 
 %% @private
 %% @doc Handling call messages

apps/modbus/src/modbus_service.erl

@@ -241,5 +241,9 @@ retry_connect() ->
 create_log_file(undefined) ->
     undefined;
 create_log_file(FileName) ->
-    {ok, FilePid} = modbus_logger:start_link(FileName),
-    FilePid.
+    case modbus_logger:start_link(FileName) of
+        {ok, FilePid} ->
+            FilePid;
+        _ ->
+            undefined
+    end.