Subprocess.Popen：将stdout和stderr克隆到终端和变量

Question

Subprocess.Popen：将stdout和stderr克隆到终端和变量

是否可以修改以下代码以从'stdout'和'stderr'打印输出：

• 印在终端上（实时），

• 最后存储在out和errs变量中？

代码：

#!/usr/bin/python3# -*- coding: utf-8 -*-import subprocessdef run_cmd(command, cwd=None):
    p = subprocess.Popen(command, cwd=cwd, shell=False,
                         stdout=subprocess.PIPE,
                         stderr=subprocess.PIPE)
    outs, errs = p.communicate()
    rc = p.returncode
    outs = outs.decode('utf-8')
    errs = errs.decode('utf-8')

    return (rc, (outs, errs))

Answer 1

要在单个线程中逐行捕获并同时显示子进程中的stdout和stderr，可以使用异步I / O：#!/usr/bin/env python3import asyncioimport osimport sysfrom asyncio.subprocess import [e-mail] read_stream_and_display(stream, display):     """Read from stream line by line until EOF, display, and capture the lines.     """     output = []     while True:         line = yield from stream.readline()         if not line:             break         output.append(line)         display(line) # assume it doesn't block     return b''.join(output)@asyncio.coroutinedef read_and_display(*cmd):     """Capture cmd's stdout, stderr while displaying them as they arrive     (line by line).     """     # start process     process = yield from asyncio.create_subprocess_exec(*cmd,             stdout=PIPE, stderr=PIPE)     # read child's stdout/stderr concurrently (capture and display)     try:         stdout, stderr = yield from asyncio.gather(             read_stream_and_display(process.stdout, sys.stdout.buffer.write),             read_stream_and_display(process.stderr, sys.stderr.buffer.write))     except Exception:         process.kill()         raise     finally:         # wait for the process to exit         rc = yield from process.wait()     return rc, stdout, stderr# run the event loopif os.name == 'nt':     loop = asyncio.ProactorEventLoop() # for subprocess' pipes on Windows     asyncio.set_event_loop(loop)else:     loop = asyncio.get_event_loop()rc, *output = loop.run_until_complete(read_and_display(*cmd))loop.close()