subprocess python filenotfounderror:[winerror 2]

Question

我一直在使用Jupyter Notebook 从kaggle学习主成分分析),但是当我运行这段代码时

     from subprocess import check_output
     print(check_output(["ls", "../input"]).decode("utf8"))

我在下面收到了一个错误

FileNotFoundError Traceback (most recent call last)
<ipython-input-3-de0e39ca3ab8> in <module>()
      1 from subprocess import check_output
----> 2 print(check_output(["ls", "C:/Users/wanglei/Documents/input"]).decode("utf8"))

D:\Anaconda3\lib\subprocess.py in check_output(timeout, *popenargs, **kwargs)
    624 
    625     return run(*popenargs, stdout=PIPE, timeout=timeout, check=True,
--> 626                **kwargs).stdout
    627 
    628 

D:\Anaconda3\lib\subprocess.py in run(input, timeout, check, *popenargs, **kwargs)
    691         kwargs['stdin'] = PIPE
    692 
--> 693     with Popen(*popenargs, **kwargs) as process:
    694         try:
    695             stdout, stderr = process.communicate(input, timeout=timeout)

D:\Anaconda3\lib\subprocess.py in __init__(self, args, bufsize, executable, stdin, stdout, stderr, preexec_fn, close_fds, shell, cwd, env, universal_newlines, startupinfo, creationflags, restore_signals, start_new_session, pass_fds)
    945                                 c2pread, c2pwrite,
    946                                 errread, errwrite,
--> 947                                 restore_signals, start_new_session)
    948         except:
    949             # Cleanup if the child failed starting.

D:\Anaconda3\lib\subprocess.py in _execute_child(self, args, executable, preexec_fn, close_fds, pass_fds, cwd, env, startupinfo, creationflags, shell, p2cread, p2cwrite, c2pread, c2pwrite, errread, errwrite, unused_restore_signals, unused_start_new_session)
   1222                                          env,
   1223                                          cwd,
-> 1224                                          startupinfo)
   1225             finally:
   1226                 # Child is launched. Close the parent's copy of those pipe

路径是正确的,似乎来自子进程的所有调用都会失败.

有谁知道为什么会这样？

Answer 1

此代码运行该ls命令,该命令可在所有符合POSIX的系统上使用.

您正在使用Microsoft Windows.默认情况下,Microsoft Windows不符合POSIX.例如,没有ls二进制文件.因此,子进程找不到该文件ls,从而发出一个FileNotFoundError.

您可以在Windows上安装Microsoft的Bash,它将为您提供ls.

但是,列出目录的pythonic和更便携的方法不是首先使用子进程,而是内置os.listdir:

import os
print(os.listdir('../input'))