#!/usr/bin/env bash min_uid=1000 declare -i _id=$(expr $min_uid - 1) while true ; do ((_id++)) $(id $_id > /dev/null 2>&1) && continue $(cat /etc/group | cut -d ':' -f3 | grep -q $_id 2> /dev/null) && continue break done echo echo " Next free uid/gid pair:" echo echo -e " uid: \033[1m$_id\033[m" echo -e " gid: \033[1m$_id\033[m" echo exit 0