diff --git a/mcts/mcts_main.cc b/mcts/mcts_main.cc
index fd91597..652bdd0 100644
--- a/mcts/mcts_main.cc
+++ b/mcts/mcts_main.cc
@@ -233,7 +233,7 @@ std::pair<bool, std::string> GTPExecute(MCTSEngine &engine, const std::string &c
             engine.Move(-1, -1);
         }
         engine.Move(x, y);
-        fprintf(stderr, "%s\n", engine.GetDebugger().GetLastMoveDebugStr().c_str());
+        std::cerr << engine.GetDebugger().GetLastMoveDebugStr() << std::endl;
         return {true, ""};
     }
     if (op == "genmove") {
@@ -246,7 +246,7 @@ std::pair<bool, std::string> GTPExecute(MCTSEngine &engine, const std::string &c
         GoCoordId x = -1, y = -1;
         engine.GenMove(x, y);
         engine.Move(x, y);
-        fprintf(stderr, "%s\n", engine.GetDebugger().GetLastMoveDebugStr().c_str());
+        std::cerr << engine.GetDebugger().GetLastMoveDebugStr() << std::endl;
         return {true, EncodeMove(x, y)};
     }
     if (op == "final_score") {
@@ -267,6 +267,7 @@ void GTPServing(std::istream &in, std::ostream &out)
 {
     auto engine = InitEngine(FLAGS_config_path);
     InitMoves(*engine, FLAGS_init_moves);
+    std::cerr << std::flush;
 
     int id;
     bool has_id, succ;
diff --git a/scripts/start_gpu.bat b/scripts/start_gpu.bat
index 3d03ec9..95e070c 100644
--- a/scripts/start_gpu.bat
+++ b/scripts/start_gpu.bat
@@ -15,6 +15,6 @@ echo log to %CD%\log >&2
 md log 2>NUL
 
 echo start mcts_main >&2
-call x64\Release\mcts_main --config_path=%config% --gtp --log_dir=log --v=1
+x64\Release\mcts_main --config_path=%config% --gtp --log_dir=log --v=1
 
 popd
\ No newline at end of file