Mini Shell

#!/usr/bin/sh

usage() {
	cat <<-EOF
	Usage: create-cracklib-dict [options] wordlist ...
	
	This script takes one or more word list files as arguments
	and converts them into cracklib dictionaries for use
	by password checking programs. The results are placed in
	the default compiled-in dictionary location.
	
	If you wish to store the dictionary in a different location,
	use the cracklib-format and cracklib-packer commands directly.
	
	Options:
	  -o, --output <file>   Alternative output file for cracklib-packer
	  -h, --help            This help output
	
	Example:
	create-cracklib-dict /usr/share/words
	EOF
	if [ -n "$*" ] ; then
		echo 1>&2
		echo "Error: $*" 1>&2
		exit 1
	else
		exit 0
	fi
}

output=""
while [ -n "$1" ] ; do
	case $1 in
		-o|--output) output=$2; shift;;
		-h|--help)   usage;;
		--)          break;;
		-*)          usage "unknown option '$*'";;
		*)           break;;
	esac
	shift
done

[ -z "$*" ] && usage

exec cracklib-format "$@" | cracklib-packer ${output}