static nio_t *open_tap_device(const char *dev_name)
{
  nio_t *nio;

  printf("Opening TAP device %s\n", dev_name);
  nio = create_nio_tap((char *)dev_name);
  if (!nio)
    fprintf(stderr, "unable to open TAP device\n");
  return nio;
}
static nio_t *open_tap_device(const char *dev_name)
{
  nio_t *nio;

  printf("Opening TAP device %s\n", dev_name);
  nio = create_nio_tap((char *)dev_name);
  if (!nio)
    fprintf(stderr, "unable to open TAP device\n");
  return nio;
}