You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: simple_tcp_server.go
    path of file: ./repos/the-way-to-go_ZH_CN/eBook/examples/chapter_15
    
    the code of the file until where you have to start completion: // Simple multi-thread/multi-core TCP server.
package main

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

const maxRead = 25

func main() {
	flag.Parse()
	if flag.NArg() != 2 {
		panic("usage: host port")
	}
	hostAndPort := fmt.Sprintf("%s:
    
func initServer(hostAndPort string) *net.TCPListener {
	serverAddr, err := net.ResolveTCPAddr("tcp", hostAndPort)
	checkError(err, "Resolving address:port failed: '"+hostAndPort+"'")
	listener, err := net.ListenTCP("tcp", serverAddr)
	checkError(err, "ListenTCP: ")
	println("Listening to: ", listener.Addr().String())
	return listener
}