timer.go

package main

import (
	"fmt"
	"math/rand"
	"time"
)

func worker(pipeline chan<- int, counter int) {
	t := rand.Intn(10)
	d := time.Duration(t)
	fmt.Println(t)
	time.Sleep(time.Second * d)
	pipeline <- counter
}

func main() {
	timer := time.NewTimer(2 * time.Second)
	pipeline := make(chan int, 100)
	counter := 0

	for {
		timer.Reset(2 * time.Second)
		counter++
		go worker(pipeline, counter)

		select {
		case <-timer.C:
			fmt.Println("time out")
		case data := <-pipeline:
			fmt.Println("receive ", data)
		}
	}

}