01-11-waitgroup-eg.go

package main

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

/**
WaitGroup の使い方
*/
func main() {
	var wg sync.WaitGroup

	wg.Add(1)
	go func() {
		defer wg.Done()
		fmt.Println("now 1st go func")
		time.Sleep(1 * time.Second)
		fmt.Println("now 1st go func done")
	}()

	wg.Add(1)
	go func() {
		defer wg.Done()
		fmt.Println("now 2nd go func")
		time.Sleep(3 * time.Second)
		fmt.Println("now 2nd go func done")
	}()

	fmt.Println("befer wait")
	wg.Wait()
	fmt.Println("Done")
}