从 python 脚本使用 cat 命令时收到错误消息 "raise CalledProcessError(retcode, cmd)"

Question

我正在使用我之前使用的包子流程：

from subprocess import check_call, STDOUT
import os
import sys

for file in os.listdir('directory/'):
    if '1' in file:
        for file_ in os.listdir('directory/'):
            if '2' in file_:
                command = f"cat directory/file1 directory/file2 > directory/file3"
                check_call(command.split(), stdout=sys.stdout, stderr=STDOUT)

整个错误信息：

cat: >: No such file or directory
cat: directory/file3: No such file or directory
Traceback (most recent call last):
  File "/home/script.py", line 12, in <module>
    check_call(command.split(), stdout=sys.stdout, stderr=STDOUT)
  File "/usr/lib64/python3.6/subprocess.py", line 311, in check_call
    raise CalledProcessError(retcode, cmd)
subprocess.CalledProcessError: Command '['cat', 'directory/file1', 'directory/file2', '>', 'directory/file3']' returned non-zero exit status 1.

当我运行命令

cat directory/file1 directory/file2 > directory/file3

在 Linux 上工作正常。

有人知道问题出在哪里吗？

Answer 1

check_call 不支持像“>”这样的 shell 操作，如果你想这样做，你需要一个子 shell:

import subprocess
import os

for file in os.listdir('directory/'):
    if '1' in file:
        for file_ in os.listdir('directory/'):
            if '2' in file_:
                command = f"cat directory/file1 directory/file2 > directory/file3"
                process = subprocess.Popen(command, shell=True, stdout=subprocess.PIPE)
                out, err = process.communicate()

                print("STDOUT:" + str(out))

从 python 脚本使用 cat 命令时收到错误消息 "raise CalledProcessError(retcode, cmd)"

Getting the error message "raise CalledProcessError(retcode, cmd)" when using the cat command from a python script

python

linux

subprocess