pacman-list-disowned-files

#!/usr/bin/env sh

tmp=${TMPDIR-/tmp}/pacman-disowned-$UID-$$
db=$tmp/db
fs=$tmp/fs

mkdir "$tmp"
trap 'rm -rf "$tmp"' EXIT

pacman -Qlq | sort -u > "$db"

find /etc /opt /usr ! -name lost+found \( -type d -printf '%p/\n' -o -print \) | sort > "$fs"

comm -23 "$fs" "$db"