子流程库将不会执行compgen [英] Subprocess library won't execute compgen

问题描述

我正在尝试在Linux(Lubuntu)机器上提供每个命令的列表.我想在Python中进一步处理该列表.通常，要在控制台中列出命令，我会写"compgen -c"，它将结果打印到stdout.

I am trying to make list of every command available on my linux (Lubuntu) machine. I would like to further work with that list in Python. Normally to list the commands in the console I would write "compgen -c" and it would print the results to stdout.

我想使用Python子进程库执行该命令，但它给了我一个错误，我不知道为什么.

I would like to execute that command using Python subprocess library but it gives me an error and I don't know why.

代码如下:

   #!/usr/bin/python

   import subprocess

   #get list of available linux commands
   l_commands = subprocess.Popen(['compgen', '-c'])

   print l_commands

这是我遇到的错误:

   Traceback (most recent call last):
     File "commands.py", line 6, in <module>
       l_commands = subprocess.Popen(['compgen', '-c'])
     File "/usr/lib/python2.7/subprocess.py", line 679, in __init__
       errread, errwrite)
     File "/usr/lib/python2.7/subprocess.py", line 1249, in _execute_child
       raise child_exception
   OSError: [Errno 2] No such file or directory

我被困住了.你们能帮我吗?如何使用子进程执行compgen命令?

I'm stuck. Could you guys help me with this? How to I execute the compgen command using subprocess?

推荐答案

compgen 是内置的bash命令，在shell中运行它:

compgen is a builtin bash command, run it in the shell:

from subprocess import check_output

output = check_output('compgen -c', shell=True, executable='/bin/bash')
commands = output.splitlines()

您也可以将其写为:

output = check_output(['/bin/bash', '-c', 'compgen -c'])

但是它把必需部分( compgen )放在最后，所以我更喜欢第一个变体.

But it puts the essential part (compgen) last, so I prefer the first variant.

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