Operate on a byte level instead of utf8 strings only

pipe_io_server/pipe_writer_thread.py

@@ -17,13 +17,13 @@ class PipeWriterThread(Thread):
     @terminate_process_on_failure
     def run(self):
         try:
-            with open(self._pipe_path, 'w') as pipe:
+            with open(self._pipe_path, 'wb') as pipe:
                 while True:
                     message = self._write_queue.get(block=True)
                     if message is None:
                         self._stop_event.set()
                         break
-                    pipe.write(f'{message}\n')
+                    pipe.write(message + b'\n')
                     pipe.flush()
         except BrokenPipeError:
             self._stop_event.set()
@@ -34,4 +34,4 @@ class PipeWriterThread(Thread):
 
     def unblock(self):
         self._write_queue.put(None)
-        open(self._pipe_path, 'r').close()
+        open(self._pipe_path, 'rb').close()