Generate an XKCD #936 style 4 word password

cat /usr/share/dict/words | grep -P ^[a-z].* | grep -v "'s$" | grep -Pv ^.\{1,15\}$ | shuf -n4 | tr '\n' ' ' | sed 's/$/\n/'
The first grep rejects capitalised words since the dict has proper nouns in it that you mightn't want to use. The second grep rejects words with ending in apostrophe s, and the third forces the words to be at least 15 characters long.
Sample Output
counterproductive unreasonableness multimillionaires extemporaneously

By: bugmenot
2011-08-15 01:03:48

12 Alternatives + Submit Alt

What Others Think

You almost never need cat and grep in the same command.
dbbolton · 562 weeks and 1 day ago
grep '[a-z]\{15,\}' /usr/share/dict/words
putnamhill · 562 weeks and 1 day ago
I love the commands where cat(1) is piped into grep(1). Gives me a warm fuzzy feeling inside. :)
atoponce · 561 weeks and 3 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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