1 0388c856 2025-03-12 boredpast #!/bin/sh
 2 0388c856 2025-03-12 boredpast # entropy: calculates the entropy of a password given the length and number of
 3 0388c856 2025-03-12 boredpast # possiblities
 4 0388c856 2025-03-12 boredpast 
 5 0388c856 2025-03-12 boredpast num=0
 6 0388c856 2025-03-12 boredpast [ "$1" = '-n' ] && { num=1; shift; }
 7 0388c856 2025-03-12 boredpast [ "$#" -ne 2 ] && { echo "usage: ${0##*/} [-n] possibilites length " 1>&2; exit 1; }
 8 0388c856 2025-03-12 boredpast echo "l($1^$2)/l(2)" | bc -l | xargs printf "%.2f"
 9 0388c856 2025-03-12 boredpast [ "$num" -eq 0 ] && printf " bits of entropy"
10 0388c856 2025-03-12 boredpast printf "\n"