如何使用asyncio从子进程中流式输出stdoutstderr，然后获取其退出代码？

如何使用asyncio从子进程中流式输出stdout / stderr，然后获取其退出代码？

到目前为止，我想出的解决方案使用SubprocessProtocol来接收子进程的输出，并使用关联的传输来获取该进程的退出代码。我不知道这是否是最佳选择。我的方法基于JF
Sebastian对类似问题
的回答。

import asyncioimport contextlibimport osimport localeclass SubprocessProtocol(asyncio.SubprocessProtocol):    def pipe_data_received(self, fd, data):        if fd == 1: name = 'stdout'        elif fd == 2: name = 'stderr'        text = data.depre(locale.getpreferredencoding(False))        print('Received from {}: {}'.format(name, text.strip()))    def process_exited(self):        loop.stop()if os.name == 'nt':    # On Windows, the ProactorEventLoop is necessary to listen on pipes    loop = asyncio.ProactorEventLoop()    asyncio.set_event_loop(loop)else:    loop = asyncio.get_event_loop()with contextlib.closing(loop):    # This will only connect to the process    transport = loop.run_until_complete(loop.subprocess_exec(        SubprocessProtocol, 'python', '-c', 'print('Hello async world!')'))[0]    # Wait until process has finished    loop.run_forever()    print('Program exited with: {}'.format(transport.get_returnpre()))