示例：IPv4 输出组播接口

¥Example: IPv4 outgoing multicast interface

所有系统都在所需的物理接口上使用主机的 IP：

¥All systems use an IP of the host on the desired physical interface:

const socket = dgram.createSocket('udp4');

socket.bind(1234, () => {
  socket.setMulticastInterface('10.0.0.2');
}); 拷贝