Python 子进程 ping -h Returns 退出状态 2

Question

我想使用 Python 捕获 ping -h 输出，它导致退出状态 2。

我正在 Linux 主机上工作。

 import subprocess
 
    
    class Network_Ping ():
      
    

        def Get_Ping_Help(self):
            res = subprocess.check_output(['ping', '-h'], universal_newlines = True)
            print (res)
   
    def main():
     obj = Network_Ping()
     obj.Get_Ping_Help()


    if __name__ == "__main__":
      main()

这是输出

`Traceback (most recent call last):
  File "Network_Ping.py", line 42, in <module>
    main()
  File "Network_Ping.py", line 35, in main
    obj.Get_Ping_Help()
  File "Network_Ping.py", line 20, in Get_Ping_Help
    res = subprocess.check_output(['ping', '-h'], universal_newlines = True)
  File "/usr/lib/python3.8/subprocess.py", line 411, in check_output
    return run(*popenargs, stdout=PIPE, timeout=timeout, check=True,
  File "/usr/lib/python3.8/subprocess.py", line 512, in run
    raise CalledProcessError(retcode, process.args,
subprocess.CalledProcessError: Command '['ping', '-h']' returned non-zero exit status 2.`

该命令似乎在 shell 上正常执行。这个错误的原因是什么？我该如何解决？

Answer 1

遵循 Barmar 解决方案

这是 ping 的正常行为，但 shell 没有显示； Shell 不 return 退出状态。我们可以通过:

ping -h;echo $?

为避免检查退出状态，我们可以将subprocess.check_output()替换为subprocess.run()

并成功捕获输出。

   res = subprocess.run(['ping', '-h'],capture_output=True, text = True)

   print(res.stderr)

Python 子进程 ping -h Returns 退出状态 2

Python Subprocess ping -h Returns Exit Status 2

linux

subprocess

ping

python-3.x