package main

import (
        "net"
        "sync"
        "time"
        "runtime/pprof"
        "os"
)

func main() {
        ch := make(chan bool)
        go func() {
                var mtx sync.Mutex
                ln, err := net.Listen("tcp", "127.0.0.1:8121")
                if err != nil { panic(err) }
                ch <- true
                _, err = ln.Accept()
                if err != nil { panic(err) }
                mtx.Lock()
        }()

        <-ch

        var buf [16*1024]byte
        conn, err := net.Dial("tcp", "127.0.0.1:8121")
        if err != nil { panic(err) }
        for i := 1; i < 100; i++ {
                go func() {
                        for {
                                _, err = conn.Write(buf[:])
                                if err != nil { panic(err) }
                        }
                }()
        }

        time.Sleep(1*time.Second)
        pprof.Lookup("goroutine").WriteTo(os.Stdout, 1)
}