gotimeouts.go

package main

import (
    "fmt"
    "net"
    "sync"
    "time"
)

func main() {
    addr := net.TCPAddr{
        IP:   net.IPv4(127, 0, 0, 1),
        Port: 12346,
    }
    wg := sync.WaitGroup{}
    wg.Add(1)
    go func() {
        l, _ := net.ListenTCP("tcp4", &addr)
        conn, err := l.Accept()
        if err != nil {
            panic(err)
        }
        fmt.Println("accepted")
        for {
            conn.SetReadDeadline(time.Now().Add(time.Second * 5))
            b := make([]byte, 1024)
            fmt.Println("reading")
            n, err := conn.Read(b)
            fmt.Println("read")
            if err != nil {
                fmt.Println("err:", err)
                time.Sleep(time.Millisecond * 100)
            } else {
                fmt.Printf("read %v; %#v (%T)\n", b[:n], err, err)
            }
        }
        wg.Done()
    }()

    wg.Add(1)
    go func() {
        conn, _ := net.DialTCP("tcp4", nil, &addr)
        time.Sleep(time.Second)
        fmt.Println("client writing")
        n, err := conn.Write([]byte{1, 2, 3, 4, 5})
        fmt.Println("wrote", n, err)
        fmt.Println("client sleeping")
        time.Sleep(time.Second * 3)
        n, err = conn.Write([]byte{6, 7, 8, 9, 0})
        fmt.Println("wrote", n, err)
        time.Sleep(time.Second * 3)
        fmt.Println("client closing")
        conn.Close()
        wg.Done()
    }()

    wg.Wait()
}