zmostp/tests/echo-server/main.go

package main

import (
	"flag"
	"fmt"
	"net"
)

var flagHelp bool
var flagEcho bool

func main() {
	flag.BoolVar(&flagHelp, "h", false, "print help")
	flag.BoolVar(&flagEcho, "e", false, "echo (send back what received)")
	flag.Parse()
	if flagHelp {
		flag.PrintDefaults()
		return
	}
	ln, err := net.Listen("tcp", ":12450")
	if err != nil {
		fmt.Println("Error listening:", err.Error())
		return
	}
	defer ln.Close()

	fmt.Println("Listening on :12450")

	for {
		// 接受连接
		conn, err := ln.Accept()
		if err != nil {
			fmt.Println("Error accepting connection:", err.Error())
			return
		}
		fmt.Println("Client connected:", conn.RemoteAddr())

		// 在新的goroutine中处理连接
		go handleConnection(conn)
	}
}

func handleConnection(conn net.Conn) {
	defer conn.Close()

	// 循环读取数据并回显
	for {
		buf := make([]byte, 1024)
		// 读取数据
		n, err := conn.Read(buf)
		if err != nil {
			fmt.Println("Error reading:", err.Error())
			return
		}

		// 打印接收到的数据
		fmt.Println("Received:\n", string(buf[:n]))

		// 发送回去
		if flagEcho {
			_, err = conn.Write(buf[:n])
			if err != nil {
				fmt.Println("Error writing:", err.Error())
				return
			}
		}
	}
}