`mkarchiso` creates two files in `${airootfs_dir}` by using output redirection: - [x] `printf '' > "${airootfs_dir}/etc/machine-id"` in `_cleanup_airootfs`, - [x] `printf '%s\n' "${iso_version}" > "${airootfs_dir}/version"` in `_make_version`. If any of these are existing symlinks, then the `printf` output would be written to the symlink target. It can be a big issue in case the symlink resolves to a path outside `${airootfs_dir}`. These files should be removed with `rm -f` before being are written to.