epmd: Fix -names option on Windows

Since 3aa60cc `epmd -names` does not produce any output on Windows
anymore. This patch uses fwrite() instead of write() which adds the
necessary carriage returns to the output so that it is suitable for the
Windows cmd.exe.

A test case is added (fails on Windows without the patch).

2 files changed, 24 insertions, 3 deletions

diff --git a/erts/epmd/src/epmd_cli.c b/erts/epmd/src/epmd_cli.c
index 8817bde8d7..bd30bc35d9 100644
--- a/erts/epmd/src/epmd_cli.c
+++ b/erts/epmd/src/epmd_cli.c
@@ -118,7 +118,7 @@ void epmd_call(EpmdVars *g,int what)
     if (!g->silent) {
 	rval = erts_snprintf(buf, OUTBUF_SIZE,
 			     "epmd: up and running on port %d with data:\n", j);
-	write(1, buf, rval);
+	fwrite(buf, 1, rval, stdout);
     }
     while(1) {
 	if ((rval = read(fd,buf,OUTBUF_SIZE)) <= 0)  {
@@ -126,7 +126,7 @@ void epmd_call(EpmdVars *g,int what)
 	    epmd_cleanup_exit(g,0);
 	}
 	if (!g->silent)
-	    write(1, buf, rval); /* Potentially UTF-8 encoded */
+	    fwrite(buf, 1, rval, stdout); /* Potentially UTF-8 encoded */
     }
 }
 
diff --git a/erts/epmd/test/epmd_SUITE.erl b/erts/epmd/test/epmd_SUITE.erl
index cc24a556a3..a752abf33b 100644
--- a/erts/epmd/test/epmd_SUITE.erl
+++ b/erts/epmd/test/epmd_SUITE.erl
@@ -69,6 +69,8 @@
     returns_valid_empty_extra/1,
     returns_valid_populated_extra_with_nulls/1,
 
+    names_stdout/1,
+
     buffer_overrun_1/1,
     buffer_overrun_2/1,
     no_nonlocal_register/1,
@@ -118,6 +120,7 @@ all() ->
      too_large, alive_req_too_small_1, alive_req_too_small_2,
      alive_req_too_large, returns_valid_empty_extra,
      returns_valid_populated_extra_with_nulls,
+     names_stdout,
      {group, buffer_overrun}, no_nonlocal_register,
      no_nonlocal_kill, no_live_killing].
 
@@ -759,6 +762,24 @@ returns_valid_populated_extra_with_nulls(Config) when is_list(Config) ->
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
+names_stdout(doc) ->
+    ["Test that epmd -names prints registered nodes to stdout"];
+names_stdout(suite) ->
+    [];
+names_stdout(Config) when is_list(Config) ->
+    ?line ok = epmdrun(),
+    ?line {ok,Sock} = register_node("foobar"),
+    ?line ok = epmdrun("-names"),
+    ?line {ok, Data} = receive {_Port, {data, D}} -> {ok, D}
+		       after 10000 -> {error, timeout}
+		       end,
+    ?line {match,_} = re:run(Data, "^epmd: up and running", [multiline]),
+    ?line {match,_} = re:run(Data, "^name foobar at port", [multiline]),
+    ?line ok = close(Sock),
+    ok.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
 buffer_overrun_1(suite) ->
     [];
 buffer_overrun_1(doc) ->
@@ -968,7 +989,7 @@ epmdrun(Epmd,Args0) ->
 	       O ->
 		   " "++O
 	   end,
-  osrun("\"" ++ Epmd ++ "\"" ++ Args ++ " " ?EPMDARGS " -port " ++ integer_to_list(?PORT)).
+  osrun("\"" ++ Epmd ++ "\"" ++ " " ?EPMDARGS " -port " ++ integer_to_list(?PORT) ++ Args).
 
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%