Golang UDP multicast not working in windows10 - go

Question

I developed an example that uses udp multicast to send and receive data,it work at linux but not wort at window10.
I try to developed another udp multicast application by Java, it works in the same environment!
Where is the problem?
Golang code:
package main
import (
"flag"
"fmt"
"net"
"strings"
)
var (
bind = flag.String("bind", "239.255.0.0", "bind")
port = flag.Int("port", 2222, "port")
cmd = flag.String("cmd", "server", "Command")
)
func main() {
flag.Parse()
addr, err := net.ResolveUDPAddr("udp4", fmt.Sprintf("%s:%d", *bind, *port))
if err != nil {
panic(err)
}
switch *cmd {
case "server":
{
startServer(addr)
}
case "client":
{
startClient(addr, strings.Join(flag.Args(), ""))
}
}
}
func startServer(addr *net.UDPAddr) {
conn, err := net.ListenMulticastUDP("udp4", nil, addr)
if err != nil {
panic(err)
} else {
fmt.Println("Server was started")
}
var buff = make([]byte, 1600)
for {
l, remoteAddr, err := conn.ReadFromUDP(buff)
if err != nil {
panic(err)
}
fmt.Printf("read data from %v, data: %s\n", remoteAddr, string(buff[0:l]))
}
}
func startClient(addr *net.UDPAddr, msg string) {
conn, err := net.DialUDP("udp4", nil, addr)
if err != nil {
panic(err)
}
l, err := conn.Write([]byte(msg))
if err != nil {
panic(err)
} else {
fmt.Printf("Wrote byte length %d\n", l)
}
conn.Close()
}

Answer 1

Eureka!
The problem was caused by "The Winsock version of the IP_MULTICAST_LOOP option is semantically different than the UNIX version of the IP_MULTICAST_LOOP option":
In Winsock, the IP_MULTICAST_LOOP option applies only to the receive path.
In the UNIX version, the IP_MULTICAST_LOOP option applies to the send path.
https://learn.microsoft.com/en-us/windows/win32/winsock/ip-multicast-2
How to set IP_MULTICAST_LOOP on multicast UDPConn in Golang