/ server.go /

package main

import (

"fmt""net""os")

func checkError(err error) {

if err != nil { fmt.Println("Error: %s", err.Error())os.Exit(1)}}

func recvUDPMsg(conn *net.UDPConn) {

var buf [20]byte

n, raddr, err := conn.ReadFromUDP(buf[0:])    if err != nil {            return    }    fmt.Println("msg is ", string(buf[0:n]))    //WriteToUDP    //func (c *UDPConn) WriteToUDP(b []byte, addr *UDPAddr) (int, error)    _, err = conn.WriteToUDP([]byte("nice to see u"), raddr)    checkError(err)

}

func main() {

udp_addr, err := net.ResolveUDPAddr("udp", ":9098")checkError(err)

conn, err := net.ListenUDP("udp", udp_addr)    defer conn.Close()    checkError(err)    //go recvUDPMsg(conn)    for {            recvUDPMsg(conn)    }

}

/ client.go /

package main

import (

"fmt""net""os"// "io")

func main() {

conn, err := net.Dial("udp", "127.0.0.1:9098")defer conn.Close()if err != nil { os.Exit(1)}

conn.Write([]byte("Hello world!"))    fmt.Println("send msg")    var msg [20]byte    conn.Read(msg[0:])    fmt.Println("msg is", string(msg[0:10]))

}