Python Error handling cant except error's

Question

I am trying this code:

try:
    res = subprocess.Popen('bgpq3 -4 {} -m 24 -l {}'.format('MAIyNT- 
AS38082','12414'), shell=True,
    universal_newlines=True,
    stdout=subprocess.PIPE).communicate()[0]
except Exception:
       print("Wrong")
       #do this code

The output is ?

ERROR:Unable to parse prefix 'MAIyNT-AS38082', af=2 (inet), ret=0
ERROR:Unable to parse prefix MAIyNT-AS38082
ERROR:Unable to add prefix MAIyNT-AS38082 (bad prefix or address-family)

so i am not able to use Error handling!!

Any Idea?

No because when i use the command without stderr and subprocess ! i get the same error — ete eteq, Oct 04 '18 at 11:54
try: res = subprocess.Popen('bgpq3 -4 {} -m 24 -l {}'.format('MAIyNT- AS38082','12414') , shell=True, universal_newlines=True, stdout=subprocess.PIPE).communicate()[0] except Exception: print("Wrong") this is work for me may be you need to format code to properly — Jignasha Royala, Oct 04 '18 at 11:55
bgpq3 -4 MAIyNT-AS38082 -m 24 -l AS38082 Results the same error — ete eteq, Oct 04 '18 at 11:56

Jab · Answer 1 · 2018-10-04T12:33:37.287

0

You're only handling errors of type exception here. You only need to use except:. This way you're catching all errors that occur in the code.

try:
    #your code
except Exception as e:
    #handle the exception

For more information refer to the docs I got from a quick google ;)

edited Oct 04 '18 at 12:33

answered Oct 04 '18 at 11:57

Jab

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Thanks for the knowledge. @Gsk I was only suggesting as a quick dirty fix. I edited my answer. Although yours is more useful. – Jab Oct 04 '18 at 12:34

score 0 · Answer 2 · answered Oct 04 '18 at 12:00

when you write except Exception: you are not catching all the exception: the system exit errors and OS errors (as BaseException, SystemExit, KeyboardInterrupt and GeneratorExit) are excluded.

Most of the exceptions of subprocess are OSError.
Since you did not report the full traceback of the error, I may only assume that you're getting one of these errors, and you can catch them using:

except subprocess.CalledProcessError:

or

except OSError:

as PEP 8 suggest, you should NOT use except: alone, even if it will work in your case.
As a rule of thumb, always catch the exact exception you espect to be raised!

don't you have also a line where the error occurs or something else? — Gsk, Oct 04 '18 at 12:10

Python Error handling cant except error's

2 Answers2