Python子进程将 child 的输出输出到文件和终端？

Question

我正在运行一个脚本，该脚本使用

执行多个可执行文件

subprocess.call(cmdArgs,stdout=outf, stderr=errf)

当 outf/errf 为 None 或文件描述符时(stdout/stderr 的不同文件) .

有什么方法可以执行每个 exe，以便将 stdout 和 stderr 一起写入文件和终端？

Answer 1

call()功能只是Popen(*args, **kwargs).wait() .您可以直接调用 Popen 并使用 stdout=PIPE 参数从 p.stdout 读取:

#!/usr/bin/env python
import sys
from subprocess import Popen, PIPE
from threading import Thread


def tee(infile, *files):
    """Print `infile` to `files` in a separate thread."""

    def fanout(infile, *files):
        with infile:
            for line in iter(infile.readline, b""):
                for f in files:
                    f.write(line)

    t = Thread(target=fanout, args=(infile,) + files)
    t.daemon = True
    t.start()
    return t


def teed_call(cmd_args, **kwargs):
    stdout, stderr = [kwargs.pop(s, None) for s in ["stdout", "stderr"]]
    p = Popen(
        cmd_args,
        stdout=PIPE if stdout is not None else None,
        stderr=PIPE if stderr is not None else None,
        **kwargs
    )
    threads = []
    if stdout is not None:
        threads.append(
            tee(p.stdout, stdout, getattr(sys.stdout, "buffer", sys.stdout))
        )
    if stderr is not None:
        threads.append(
            tee(p.stderr, stderr, getattr(sys.stderr, "buffer", sys.stderr))
        )
    for t in threads:
        t.join()  # wait for IO completion
    return p.wait()


outf, errf = open("out.txt", "wb"), open("err.txt", "wb")
assert not teed_call(["cat", __file__], stdout=None, stderr=errf)
assert not teed_call(["echo", "abc"], stdout=outf, stderr=errf, bufsize=0)
assert teed_call(["gcc", "a b"], close_fds=True, stdout=outf, stderr=errf)