if (element_len != 4) return -1;
int decode_rivergauge(unsigned char *element, int element_len) {	// 0x42 River Flow Gauge - 1/64 m^3/sec, centimeters	unsigned int flow;	unsigned int height;	float flowm;	float heightm;	if (element_len != 4) return -1;	flow = get16(element);	height = get16(element+2);	flowm = (float)flow / 64;	heightm = (float)height / 100;	lprintf(T_OPENTRAC, "River flow rate: %f Cu M/Sec  Height: %f M\r\n",			flowm, heightm);	return 0;}