Python的Subprocess.Popen with Shell = True.等到完成 [英] Python's Subprocess.Popen With Shell=True. Wait till it is completed

问题描述

提交一个复杂的 cmd 字符串，该字符串由可执行文件的完整文件路径组成，多个标志，参数，参数，输入和输出似乎需要我设置 shell = True strong>否则为子进程.Popen除了简单的可执行文件路径(文件路径中没有空格)之外，还无法理解其他任何复杂的东西.

Submitting a complex cmd string made of a full file path to an executable, the multiple flags, arguments, parameters, inputs and outputs seems to require me to set shell=True otherwise subprocess.Popen is not able understand anything more complex than just a simple path to executable (with no spaces in a filepath).

在我的示例中，我有一个很长的cmd:

In my example I have quite a long cmd:

cmd = " '/Application/MyApp.app/Contents/MacOS/my_executable' '/Path/to/input/files' -some -flags -here -could -be -a -lot '/full/path/to/output/files' "

将此cmd提交给 subprocess.Popen 会导致错误，提示有关路径的某些内容而无法找到它.

Submitting this cmd to subprocess.Popen " results to an error that complains on something about the path and not being able to find it.

所以不要使用:

proc = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)

check_call 似乎运行良好:

proc = subprocess.check_call(cmd, shell=True)

有趣，只有在 shell 设置为 True

shell=True 

subprocess.check_call 与提供的cmd一起使用.

the subprocess.check_call works with a supplied cmd.

副作用是其余代码似乎可以继续运行，而无需等待 subprocess.check_call(cmd，shell = True)首先完成.

The side effect is that the rest of the code seems proceeds running without waiting for subprocess.check_call(cmd, shell=True) to finish first.

设计代码的方式是，其余执行依赖于subprocess.check_call(cmd, shell=True)的结果.

The code is designed the way that the rest of the execution is dependent on a result of subprocess.check_call(cmd, shell=True).

我想知道是否有强制代码执行以等待subprocess.check_call(cmd，shell = True)完成的方法.预先感谢！

I wonder if there is anyway to enforce the code execution to wait till subprocess.check_call(cmd, shell=True) is finished. Thanks in advance!

推荐答案

正如@mikkas建议将其用作list一样，这是一个有效的示例:

As @mikkas suggest just use it as a list here is a working example:

mainProcess = subprocess.Popen(['python', pyfile, param1, param2], stdout=subprocess.PIPE, stderr=subprocess.PIPE)

# get the return value from the method
communicateRes = mainProcess.communicate()

stdOutValue, stdErrValue = communicateRes

您正在呼叫python.exe pyfile param1 param2

通过使用communicate()，您可以将stdout和stderr作为Tuple

By using communicate() you can get the stdout and stderr as a Tuple

您可以使用python方法split()将字符串拆分为列表，例如:

You can use python method split() to split your string to a list for example:

cmd = "python.exe myfile.py arg1 arg2"

cmd.split(" ")

输出:

['python.exe', 'myfile.py', 'arg1', 'arg2']

这篇关于Python的Subprocess.Popen with Shell = True.等到完成的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！