#!/usr/bin/bash parse() { while read line; do [ "${line:0:1}" = '#' -o "${line:0:1}" = ';' ] && continue line="${line## *}" [ -z "$line" ] && continue set -- $line case "$1" in ('u') echo "user($2)" echo "group($2)" # TODO: user:group support ;; ('g') echo "group($2)" ;; ('m') echo "user($2)" echo "group($3)" ;; esac done } while read fn; do parse < "$fn" done