ctlmgr,worker: set PYTHONUNBUFFERED for subprocesses

artiq/devices/ctlmgr.py

@@ -81,9 +81,12 @@ class Controller:
                 logger.info("Starting controller %s with command: %s",
                             self.name, self.command)
                 try:
+                    env = os.environ.copy()
+                    env["PYTHONUNBUFFERED"] = "1"
                     self.process = await asyncio.create_subprocess_exec(
                         *shlex.split(self.command),
-                        stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+                        stdout=subprocess.PIPE, stderr=subprocess.PIPE,
+                        env=env)
                     asyncio.ensure_future(
                         LogParser(self._get_log_source).stream_task(
                             self.process.stdout))

artiq/master/worker.py

@@ -81,10 +81,13 @@ class Worker:
             if self.closed.is_set():
                 raise WorkerError("Attempting to create process after close")
             self.ipc = pipe_ipc.AsyncioParentComm()
+            env = os.environ.copy()
+            env["PYTHONUNBUFFERED"] = "1"
             await self.ipc.create_subprocess(
                 sys.executable, "-m", "artiq.master.worker_impl",
                 self.ipc.get_address(), str(log_level),
-                stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+                stdout=subprocess.PIPE, stderr=subprocess.PIPE,
+                env=env)
             asyncio.ensure_future(
                 LogParser(self._get_log_source).stream_task(
                     self.ipc.process.stdout))