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Random password generating function

Terminal - Random password generating function
mkpasswd() { head -c $(($1)) /dev/urandom | uuencode - | sed -n 's/.//;2s/\(.\{'$1'\}\).*/\1/p' ;}
2009-11-19 14:27:52
User: taliver
Functions: head sed uuencode
-3
Random password generating function

This uses urandom to produce a random password. The random values are uuencoded to ensure only printable characters. This only works for a number of characters between 1 and 60.

Alternatives

There are 6 alternatives - vote for the best!

Terminal - Alternatives
< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c6
2009-02-24 09:43:40
User: Blackbit
Functions: head tr
11

If you want a password length longer than 6, changing the -c6 to read -c8 will give you 8 random characters instead of 6. To end up with a line-feed, use this with echo:

# echo `< /dev/urandom tr -dc _A-Z-a-z-0-9 | head -c6`

dd if=/dev/urandom count=200 bs=1 2>/dev/null | tr "\n" " " | sed 's/[^a-zA-Z0-9]//g' | cut -c-16
openssl rand 6 -base64
2011-10-05 14:24:41
User: Le_Jax
0

just change 6 to 9 or 12 or more (multiple of 3) to have bigger password

Know a better way?

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What others think

Actually, you can just do "head -c $1". I originally was diving by 3 to reduce the amount of random characters needed (in case I switched to random), but then forgot that I stopped doing any math on the value.

Comment by taliver 251 weeks and 5 days ago

And, actually, a little smaller is:

mkpasswd() { head -c $1 /dev/urandom | uuencode - | sed -n '2s/.\(.\{'$1'\}\).*/\1/p' ;}

Comment by taliver 251 weeks and 5 days ago

Your point of view

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