listen.go

package main

import (
	"bufio"
	"log"
	"net"
)

func handle(conn *net.TCPConn) {
	defer conn.Close()
	addr := conn.RemoteAddr()

	br := bufio.NewReader(conn)

	for {
		line, err := br.ReadString('\n')
		if err != nil {
			log.Printf("[%v] unable to read a line: %v\n", addr, err)
			return
		}
		log.Printf("[%v] %s", addr, line)
	}
}

func main() {
	l, err := net.ListenTCP("tcp4", &net.TCPAddr{IP: net.IPv4(0, 0, 0, 0)})
	if err != nil {
		log.Fatalf("unable to open a tcp port: %v\n", err)
	}
	log.Printf("listening for tcp connections on %v\n", l.Addr())
	for {
		conn, err := l.AcceptTCP()
		if err != nil {
			log.Fatalf("unable to handle a new incoming connection: %v\n", err)
		}

		log.Printf("accepted a connection: %v\n", conn)
		go handle(conn)
	}
}