golang-study/base/goroutine/sync/main.go

package main

import (
	"fmt"
	"sync"
)

var wg = new(sync.WaitGroup)

func hello(i int) {
	defer wg.Done()
	fmt.Println("hello:", i)
}

func main() {
	for i := 0; i < 100; i++ {
		// 开启一个单独的 goroutine 任务
		wg.Add(1)
		go hello(i)
	}

	fmt.Println("main")
	// 等待所有线程结束
	wg.Wait()
}