Exercise 8.8: Using a select statement, add a timeout to the echo server from Section 8.3 so that it disconnects any client that shouts nothing within 10 seconds.

gopl Exercise 8.8.go

package main

import (
	"bufio"
	"fmt"
	"io"
	"net"
	"time"
)

func main() {
	l, err := net.Listen("tcp", ":8080")
	if nil != err {
		panic(err)
	}
	for {
		con, err := l.Accept()
		if err != nil {
			continue
		}
		go func(c net.Conn) {
			defer c.Close()
			ch := make(chan string)
			go func(ch chan<- string) {
				s := bufio.NewScanner(c)
				for s.Scan() {
					ch <- s.Text()
				}
			}(ch)
			for {
				select {
				case <-time.After(10 * time.Second):
					fmt.Println("time out")
					return
				case text := <-ch:
					io.WriteString(c, text)
				}
			}

		}(con)
	}
}