如何在python中调用外部程序并检索输出并返回代码?

时间:2009-04-01 19:25:10

标签: python return-value external-process

如何使用python脚本调用外部程序并检索输出并返回代码?

5 个答案:

答案 0 :(得分:62)

查看subprocess模块:一个简单的例子如下......

from subprocess import Popen, PIPE

process = Popen(["ls", "-la", "."], stdout=PIPE)
(output, err) = process.communicate()
exit_code = process.wait()

答案 1 :(得分:15)

按照Ambroz Bizjak之前的评论,这是一个对我有用的解决方案:

import shlex
from subprocess import Popen, PIPE

cmd = "..."
process = Popen(shlex.split(cmd), stdout=PIPE)
process.communicate()
exit_code = process.wait()

答案 2 :(得分:2)

在此处查看子流程模块:http://docs.python.org/library/subprocess.html#module-subprocess。它应该得到你需要做的。

答案 3 :(得分:2)

经过一些研究,我有以下代码,对我来说效果很好。它基本上实时打印stdout和stderr。希望它可以帮助其他需要它的人。

stdout_result = 1
stderr_result = 1


def stdout_thread(pipe):
    global stdout_result
    while True:
        out = pipe.stdout.read(1)
        stdout_result = pipe.poll()
        if out == '' and stdout_result is not None:
            break

        if out != '':
            sys.stdout.write(out)
            sys.stdout.flush()


def stderr_thread(pipe):
    global stderr_result
    while True:
        err = pipe.stderr.read(1)
        stderr_result = pipe.poll()
        if err == '' and stderr_result is not None:
            break

        if err != '':
            sys.stdout.write(err)
            sys.stdout.flush()


def exec_command(command, cwd=None):
    if cwd is not None:
        print '[' + ' '.join(command) + '] in ' + cwd
    else:
        print '[' + ' '.join(command) + ']'

    p = subprocess.Popen(
        command, stdout=subprocess.PIPE, stderr=subprocess.PIPE, cwd=cwd
    )

    out_thread = threading.Thread(name='stdout_thread', target=stdout_thread, args=(p,))
    err_thread = threading.Thread(name='stderr_thread', target=stderr_thread, args=(p,))

    err_thread.start()
    out_thread.start()

    out_thread.join()
    err_thread.join()

    return stdout_result + stderr_result

答案 4 :(得分:2)

我开发了一个小库(py-execute),它允许您执行外部程序,检索输出和重新编码,同时实时在控制台中输出:

>>> from py_execute.process_executor import execute
>>> ret = execute('echo "Hello"')
Hello
>>> ret
(0, 'Hello\n')

您可以避免通过模拟user_io打印到控制台:

>>> from mock import Mock
>>> execute('echo "Hello"', ui=Mock())
(0, 'Hello\n')

我写的是因为普通的Popen(在Python 2.7中)我在执行长输出的命令时遇到了麻烦