Create a nicely formatted secret

wachtwoordmaker.sh

#!/bin/bash
set -e

# defaults
num=24
grp=5

# ugly hack: arithmetric expansion $(()) will return 0 for non-integer arguments
if [ $(($1)) != 0 ]
then
	num=$1
fi

if [ $(($2)) != 0 ]
then
	grp=$2
fi

pwgen -s $num  -1 | perl -pe 's/.{'$grp'}(?!$)/$&-/g'

exit 0