_setup_writeSingleOption "$mask" $d/mask
_setup_writeSingleOption "$prefix" $d/prefix
- test "$dev" -o "$SETUP_NETDEV" || \
+ test -n "$dev" -o -n "$SETUP_NETDEV" || \
echo $"No device specified for interface '$idx'; do not forget to set the 'nodev' option" >&2
}