1 2T=$(mktemp -d "${TMPDIR:-/tmp}/sh-test.XXXXXXXX") || exit 3trap 'rm -rf "$T"' 0 4 5set -C 6echo . >"$T/a" && 7[ -s "$T/a" ] && 8{ ! true >"$T/a"; } 2>/dev/null && 9[ -s "$T/a" ] && 10ln -s /dev/null "$T/b" && 11true >"$T/b" 12