Here are a few title options based on your provided article, focusing on the question-and-answer format, while highlighting goroutines and parallel file downloads: **Option 1 (Focus on Goroutines):**

Golang Download Multiple Files in Parallel Using Goroutines

Is it possible to download and save files in parallel using goroutines? To demonstrate, let's delve into a provided code snippet written in Golang.

<code class="go">import (
    "encoding/json"
    "fmt"
    "io"
    "io/ioutil"
    "net/http"
    "net/url"
    "os"
    "path/filepath"
    "sync"
)
...

func main() {
    ...

    var wg sync.WaitGroup
    for i, file := range flr.FileList {
        wg.Add(1)

        go download_file(file, tr, &wg)

        if i >= 2 {
            break
        }
    }
    wg.Wait()
}

...
func download_file(file File, token TokenResponse, wg *sync.WaitGroup) {
    ...
    wg.Done()
}</code>

Understanding the Solution:

The issue arises because the main goroutine exits before all the goroutines spawned to download files complete. To rectify this, a sync.WaitGroup is introduced to track the number of goroutines running. Before the main goroutine exits, it waits until all the goroutines (running concurrently) complete.

Within each goroutine, the wg.Add method increments the count, indicating the creation of a new goroutine. After successfully downloading a file, the wg.Done method is called, decrementing the count and signaling the completion of a goroutine.

Once all the goroutines complete, the wg.Wait() method in the main goroutine unlocks and allows the main program to proceed.

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