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// Copyright © 2016 Alan A. A. Donovan & Brian W. Kernighan.
// License: https://creativecommons.org/licenses/by-nc-sa/4.0/

// See page 219.
//!+

// Clock1 is a TCP server that periodically writes the time.
package main

import (
    "io"
    "log"
    "net"
    "time"
)

func main() {
    listener, err := net.Listen("tcp", "localhost:8000")
    if err != nil {
        log.Fatal(err)
    }
    for {
        conn, err := listener.Accept()
        if err != nil {
            log.Print(err) // e.g., connection aborted
            continue
        }
        handleConn(conn) // handle one connection at a time
    }
}

func handleConn(c net.Conn) {
    defer c.Close()
    for {
        _, err := io.WriteString(c, time.Now().Format("15:04:05\n"))
        if err != nil {
            return // e.g., client disconnected
        }
        time.Sleep(1 * time.Second)
    }
}

//!-