# $FreeBSD$ bad=0 for i in 0 1 2 3; do for j in 0 1 2 3 4 5 6 7; do for k in 0 1 2 3 4 5 6 7; do case $i$j$k in 000) continue ;; esac set -- "$(printf \\$i$j$k@)" set -- "${1%@}" ff= for f in /dev/null /dev/zero /; do if [ -e "$f" ] && [ ! -e "$f$1" ]; then ff=$f fi done [ -n "$ff" ] || continue if { true <$ff$1; } 2>/dev/null; then echo "Bad: $i$j$k ($ff)" >&2 : $((bad += 1)) fi done done done exit $((bad ? 2 : 0))