Server：

package main

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

func worker(conn net.Conn) {
    defer conn.Close()
    for {
        reader := bufio.NewReader(conn)
        var buf [128]byte
        n, err := reader.Read(buf[:]) // 读取数据
        if err != nil {
            fmt.Println("Read msg from client failed ,err: ", err)
            break
        }

        resStr := string(buf[:n])
        fmt.Println("收到Client的数据：", resStr)
        conn.Write([]byte(resStr)) // 发送数据
    }
}

func main() {
    listen, err := net.Listen("tcp", "127.0.0.1:9000")
    if err != nil {
        fmt.Println("Listen failed,err: ", err)
        return
    }

    for {
        conn, err := listen.Accept() // 建立链接
        if err != nil {
            fmt.Println("Accept failed, err: ", err)
        }
        go worker(conn) // 启动一个 goroutine 处理
    }
}

Client: 

package main

import (
    "bufio"
    "fmt"
    "net"
    "os"
    "strings"
)

func main() {
    conn, err := net.Dial("tcp", "127.0.0.1:9000")
    if err != nil {
        fmt.Println("err: ", err)
    }
    defer conn.Close()

    cReader := bufio.NewReader(os.Stdin)
    for {
        input, _ := cReader.ReadString('\n')
        info := strings.Trim(input, "\r\n")
        if strings.ToUpper(info) == "Q" { // 如果输入q/Q,就退出
            return
        }
        _, err := conn.Write([]byte(info)) // 发送数据
        if err != nil {
            buf := [512]byte{}
            n, err := conn.Read(buf[:])
            if err != nil {
                fmt.Println("Client receive msg err: ", err)
                return
            }
            fmt.Println(string(buf[:n]))
        }
    }
}