Python:在 Linux 上，subprocess.Popen() 与 shell = True 一起工作很奇怪

Question

如果我在 Windows 上执行以下 python 代码:

import subprocess
subprocess.Popen( [ 'python', 'foo' ], shell = True ).communicate()

如预期的那样，我将错误写入标准输出:

python: can't open file 'foo': [Errno 2] No such file or directory

但是如果我在 linux(ubuntu，OSX - 任何)上执行相同的代码，我会启动交互式 python REPL 而不是这个文本!像这样:

user@debian:~/Documents$ python test.py
Python 2.7.3 (default, Jab 2 2013, 16:53:07)
[GCC 4.7.2] on linux2
Type "help", "copyright", "credits" or "license" for more information
>>>

为什么会有这种奇怪的行为？使用参数 ('foo') 执行 python 解释器必须在所有平台上将其置于评估模式，而不是进入 REPL 模式。

Answer 1

这在文档中有详细说明:

The shell argument (which defaults to False) specifies whether to use the shell as the program to execute. If shell is True, it is recommended to pass args as a string rather than as a sequence.

On Unix with shell=True, the shell defaults to /bin/sh. If args is a string, the string specifies the command to execute through the shell. This means that the string must be formatted exactly as it would be when typed at the shell prompt. This includes, for example, quoting or backslash escaping filenames with spaces in them. If args is a sequence, the first item specifies the command string, and any additional items will be treated as additional arguments to the shell itself.

(强调我的)