如何在python shell脚本中使用上次执行命令的返回码

Question

Dollar question mark ($?) is used to find the return value of the last executed command and I want to use it in my script but it does not work.

python version : 3.7 Library : subprocess

I searched the answer but I can't find the suit answer in python.

I tried the following code, but it doesn't work :

#!/usr/bin/python
import subprocess
subprocess.call(["ls","-l"])
if $? == 0 :
    print("is ok\n")       

Answer 1

subprocess.call will return the code and you can store it inside variable:

import subprocess
rv = subprocess.call(["ls","-l"])  # <-- result of the call is stored inside `rv` variable
if rv == 0 :                       # <-- check the variable
  print("is ok")                   # <-- no need to put additional '\n' to print statement

Prints:

... the result of `ls -l`
is ok

Answer 2

call returns an object with a returncode attribute you can check.

result = subprocess.call(["ls", "-l"])
if result.returncode == 0:
    print("is ok")