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Generate an XKCD #936 style 4 word passphrase (fast)

Terminal - Generate an XKCD #936 style 4 word passphrase (fast)
echo $(shuf -n4 /usr/share/dict/words)
2011-08-30 03:10:06
User: bohwaz
Functions: echo
Generate an XKCD #936 style 4 word passphrase (fast)

Some snippets posted are slow on big dictionaries, this one is fast.


There are 5 alternatives - vote for the best!

Terminal - Alternatives
echo $(grep "^[^'A-Z]\{3,7\}$" /usr/share/dict/words|shuf -n4)
2011-09-07 22:03:45
User: cbbrowne
Functions: echo grep

This restricts things 3 ways:

1. No capitalized words, hence no proper names.

2. No apostrophes.

3. Restricts size to range (3,7)

Know a better way?

If you can do better, submit your command here.

What others think

On Ubuntu you need to install a dictionary, like the wamerican or wbritish. A lot of words have apostrophes and other characters you might not want in your password.

Comment by floydwilde 190 weeks and 4 days ago

To get rid of the apostrophes.

Use: echo $(cat /usr/share/dict/words |grep -v "'"|shuf -n4)

Comment by d1v3rdown 190 weeks and 3 days ago


echo $(shuf -n4 /usr/share/dict/words|sed "s/'s//g")

D1v3rdown, you could have skipped the cat:

echo $(grep -v "'" /usr/share/dict/words |shuf -n4)

Also, grepping the whole file triples the time of the shuf, but the sed on the results barely changes it. Of course we're only talking about 0.02-0.06 seconds, but hey!

Comment by splante 190 weeks and 1 day ago

I prefer to get rid of proper names, as well as words involving apostrophes, which makes it a bit longer.

Comment by cbbrowne 189 weeks and 3 days ago

Your point of view

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