python subprocess.popen ping fails after no response

Asked Feb 27 '15 at 17:59

Active Feb 27 '15 at 17:59

Viewed 24 times

I have ping function below using subproces

def ping_sub1(a):
            with open(os.devnull, "wb") as limbo:
        for ip in a:
            result = subprocess.Popen(["ping", "-c", "1", "-w", "1", ip], stdout=limbo, stderr=limbo).wait()
            if result:
                a.remove(ip)
    return a

I run with 'a' list below where 123.123.123.123 is not responsive. It looks like it's removed from list but then program stops...it works only fine if all addresses are responsive.

>>> a=['10.29.1.1', '123.123.123.123', '123.123.123.123', '10.29.21.208']
>>> pingtest4.ping_sub1(a)
['10.29.1.1', '123.123.123.123', '10.29.21.208']
>>> pingtest4.ping_sub1(a)
['10.29.1.1', '10.29.21.208']
>>> pingtest4.ping_sub1(a)
['10.29.1.1', '10.29.21.208']
>>>

Please advise

asked Feb 27 '15 at 17:59

irom

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Don't modify a list while iterating over it. – Ashwini Chaudhary Feb 27 '15 at 18:02
Don't remove items from a list you are looping over; it will work if you loop in reverse or remove `ip` addresses *after* looping. – Martijn Pieters Feb 27 '15 at 18:02
here's how you could [`ping` multiple hosts using `subprocess` module in Python](http://stackoverflow.com/a/12102040/4279) – jfs Feb 27 '15 at 20:44

python subprocess.popen ping fails after no response

0 Answers0