go upd 广播

client.go

package main

import (
	"fmt"
	"net"
	"time"
)

func main() {
	var (
		conn net.Conn
		err  error
	)

	if conn, err = net.Dial("udp", "192.168.197.255:8080"); err != nil {
		panic(err)
	}

	defer func() {
		if err := conn.Close(); err != nil {
			fmt.Println(err.Error())
		}
	}()

	for {
		if _, err = conn.Write([]byte("hello guys")); err != nil {
			fmt.Printf("err: %s", err.Error())
		}
		time.Sleep(time.Second * 3)
	}
}

　　

server.go

package main

import (
	"bufio"
	"fmt"
	"net"
)

func main() {
	var (
		conn   *net.UDPConn
		err    error
		reader *bufio.Reader
	)

	if conn, err = net.ListenUDP("udp", &net.UDPAddr{
		IP:   net.IPv4(0, 0, 0, 0),
		Port: 8080,
	}); err != nil {
		panic(err)
	}

	defer func() {
		if err := conn.Close(); err != nil {
			panic(err)
		}
	}()

	for {
		reader = bufio.NewReader(conn)
		data := make([]byte, 1024)
		_, err := reader.Read(data)
		if err != nil {
			fmt.Printf("err: %s", err.Error())
			continue
		}
		fmt.Printf("result: %s\n", string(data))
	}
}