investigate IPv6 status of Alexa Top Sites

digger.py

import subprocess

with open('top-1m.csv') as f:
    for line in f:
        idx, domain = line.rstrip().split(',')
        try:
            result = subprocess.check_output(["dig", domain, "A"])
            result_a = 0 if 'ANSWER: 0' in result else 1
        except subprocess.CalledProcessError:
            result_a = 2
        try:
            result = subprocess.check_output(["dig", domain, "AAAA"])
            result_aaaa = 0 if 'ANSWER: 0' in result else 1
        except subprocess.CalledProcessError:
            result_aaaa = 2
        print "%s,%s,%d,%d" % (idx, domain, result_a, result_aaaa)

result-1k.csv

result.txt

$ awk -F, '$3==1&&$4==1{n+=1}END{print n}' result-1k.csv
176

$ awk -F, '$3==1&&$4==0{n+=1}END{print n}' result-1k.csv
798

$ awk -F, '$3==0&&$4==1{n+=1}END{print n}' result-1k.csv


$ awk -F, '$3==0&&$4==0{n+=1}END{print n}' result-1k.csv
26

$ echo 176/798 | bc -l
.22055137844611528822