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Comment by __david__ | Hacker News Reader

If you're on linux you can usually just do:

    shuf -n 5 /usr/share/dict/words

On Mac OS X you need coreutils for shuf, which you can get from brew (it's called gshuf once installed).

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I would be very cautious about using shuf for password generation, since it doesn't use a cryptographically-secure random number generator (I just checked the source).

Edit: I see that shuf permits the use of custom seeds, so you can do the following, and it will be secure:

    shuf -n 5 --random-source=/dev/urandom /usr/share/dict/words

Or:

  python -c 'import random;w=open("/usr/share/dict/words").readlines();print " ".join([random.choice(w).strip() for _ in range(5)])'

To get rid of the newlines

    shuf -n 4 /usr/share/dict/words | xargs | sed 's/ //g'

Or slightly more simply:

    echo `shuf -n 5 /usr/share/dict/words`

Maybe add this to your .bashrc file?

    randword()
    {
      if [ -z $1 ]; then
        echo `shuf --random-source=/dev/urandom -n 5 /usr/share/dict/words`
      else
        echo `shuf --random-source=/dev/urandom -n $1 /usr/share/dict/words`
      fi
    }

Test output:

    kobra@stormforge blah $ randword 4
    crackpots fragmentation maximally Bradly's
    kobra@stormforge blah $ randword 6
    turnover's nonproliferation's bestowal's sulkier hillbilly Narmada
    kobra@stormforge blah $ randword
    Marciano fibulas roadwork mobilizations organics
    kobra@stormforge blah $ randword
    coins bronzed housemother's forefather supposing

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