- * system. Linux types should use `TUN_UNET' and build the `usernet'
- * module. BSD types should use `TUN_BSD' to use the built-in `tun'
- * devices. */
+ * system. Linux types should say `TUN_LINUX' for the TUN/TAP driver if
+ * using kernel 2.4.0 or later, or say `TUN_UNET' for 2.2-series kernels and
+ * build the `usernet' module. BSD types should say `TUN_BSD' to use the
+ * built-in `tun' devices.
+ */