context

[asu126]

• http://www.flysnow.org/2017/05/12/go-in-action-go-context.html

package main

import (
	"fmt"
	"time"
	"golang.org/x/net/context"
)

func main() {
	ctx, cancel := context.WithCancel(context.Background())
	c2 := make(chan string, 1)

	go func(ctx context.Context) {
		for {
			select {
			case <-ctx.Done():
				fmt.Println("监控退出，停止了...")
				return
			default:
				fmt.Println("goroutine监控中...")
				time.Sleep(2 * time.Second)
				if 2==2{
					c2 <- "Wait repo sync end, repo sync successful ..."
				}
			}
		}
	}(ctx)
	// time.Sleep(10 * time.Second)

	select {
			case res := <-c2:
				cancel()
				fmt.Println(res)
			case <-time.After(10 * time.Second):
				fmt.Println("Wait repo sync timeout ...")
				fmt.Println("可以了，通知监控停止")
				cancel()
				return
			}
	//为了检测监控过是否停止，如果没有监控输出，就表示停止了
	fmt.Println("下载中...")
	time.Sleep(5 * time.Second)
}