package main

import (
    "fmt"
    "net/http"
    "sync"
)

func main() {
    fmt.Println("start...")
    var urls = []string{
        "https://www.baidu.com/",
        "https://www.cnblogs.com/",
        "https://www.oschina.net/",
    }

    var wg sync.WaitGroup
    for _, url := range urls {
        wg.Add(1)
        go fetch(&wg, url)
    }
    wg.Wait()
    fmt.Println("...end")
}

// fetch
func fetch(wg *sync.WaitGroup, url string) (string, error) {
    defer wg.Done()
    response, err := http.Get(url)
    if err != nil {
        return "", err
    }
    fmt.Println(fmt.Sprintf("request %s - response %s", url, response.Status))
    return response.Status, nil
}