Problems using ArduinoMDNS with WiFiSpi about wifispi HOT 13 CLOSED

any Arduino core and networking library that supports the new virtual UDP::beginMulticast(...) method

// multicast version to set fields before open  thd
uint8_t EthernetClass::socketBeginMulticast(uint8_t protocol, IPAddress ip, uint16_t port)
{
	uint8_t s, status[MAX_SOCK_NUM], chip, maxindex=MAX_SOCK_NUM;

	// first check hardware compatibility
	chip = W5100.getChip();
	if (!chip) return MAX_SOCK_NUM; // immediate error if no hardware detected
#if MAX_SOCK_NUM > 4
	if (chip == 51) maxindex = 4; // W5100 chip never supports more than 4 sockets
#endif
	//Serial.printf("W5000socket begin, protocol=%d, port=%d\n", protocol, port);
	SPI.beginTransaction(SPI_ETHERNET_SETTINGS);
	// look at all the hardware sockets, use any that are closed (unused)
	for (s=0; s < maxindex; s++) {
		status[s] = W5100.readSnSR(s);
		if (status[s] == SnSR::CLOSED) goto makesocket;
	}
	//Serial.printf("W5000socket step2\n");
	// as a last resort, forcibly close any already closing
	for (s=0; s < maxindex; s++) {
		uint8_t stat = status[s];
		if (stat == SnSR::LAST_ACK) goto closemakesocket;
		if (stat == SnSR::TIME_WAIT) goto closemakesocket;
		if (stat == SnSR::FIN_WAIT) goto closemakesocket;
		if (stat == SnSR::CLOSING) goto closemakesocket;
	}
#if 0
	Serial.printf("W5000socket step3\n");
	// next, use any that are effectively closed
	for (s=0; s < MAX_SOCK_NUM; s++) {
		uint8_t stat = status[s];
		// TODO: this also needs to check if no more data
		if (stat == SnSR::CLOSE_WAIT) goto closemakesocket;
	}
#endif
	SPI.endTransaction();
	return MAX_SOCK_NUM; // all sockets are in use
closemakesocket:
	//Serial.printf("W5000socket close\n");
	W5100.execCmdSn(s, Sock_CLOSE);
makesocket:
	//Serial.printf("W5000socket %d\n", s);
	EthernetServer::server_port[s] = 0;
	delayMicroseconds(250); // TODO: is this needed??
	W5100.writeSnMR(s, protocol);
	W5100.writeSnIR(s, 0xFF);
	if (port > 0) {
		W5100.writeSnPORT(s, port);
	} else {
		// if don't set the source port, set local_port number.
		if (++local_port < 49152) local_port = 49152;
		W5100.writeSnPORT(s, local_port);
	}
	// Calculate MAC address from Multicast IP Address
    	byte mac[] = {  0x01, 0x00, 0x5E, 0x00, 0x00, 0x00 };
    	mac[3] = ip[1] & 0x7F;
    	mac[4] = ip[2];
    	mac[5] = ip[3];
    	W5100.writeSnDIPR(s, ip.raw_address());   //239.255.0.1
    	W5100.writeSnDPORT(s, port);
    	W5100.writeSnDHAR(s, mac);
	W5100.execCmdSn(s, Sock_OPEN);
	state[s].RX_RSR = 0;
	state[s].RX_RD  = W5100.readSnRX_RD(s); // always zero?
	state[s].RX_inc = 0;
	state[s].TX_FSR = 0;
	//Serial.printf("W5000socket prot=%d, RX_RD=%d\n", W5100.readSnMR(s), state[s].RX_RD);
	SPI.endTransaction();
	return s;
}