int main (int argc, char *argv[])
{
	struct si4713_rnl rnl;
	int fd = open("/dev/radio0", O_RDWR);
	int rval;

	if (argc < 2)
		return -EINVAL;

	if (fd < 0)
		return fd;

	sscanf(argv[1], "%d", &rnl.frequency);

	rval = ioctl(fd, SI4713_IOC_MEASURE_RNL, &rnl);
	if (rval < 0)
		return rval;

	printf("received noise level: %d\n", rnl.rnl);

	close(fd);
}