main-loop.go

// Loop and make 50 go routines or cncurrent function calls....
for count < 50 {
	// Size (in no. of bytes) that has to be requested from the server
	size := int64(bpc)
	
	// If all that left is less than itself download the rest
	// This generally happens in the last connection....
	if total-size < size {
		size = total
	}
	
	// Naming the temp file for the connection....
	// Not necessary still little organised with numbers.
	// Name the files with some random string and store them in the `files` array
	num := fmt.Sprint(count + 1)
	if count+1 < 10 {
		num = fmt.Sprintf("0%s", num)
	}
	filename := filepath.Join("/tmp/", outfile, fmt.Sprintf("%s-%s", outfile, num))
	files = append(files, filename)
	// Open that temp file
	f, err := os.OpenFile(filename, os.O_CREATE|os.O_RDWR, 0755)
	check err
	// Add a Job to the Waitgroup
	c.Add(1)
	// This function will be described bottom....
	go Out(f, c, count, from, size, written)
	// Calculate the size left to be downloaded.
	total -= size
	// Calculate from which byte size the next request has to be made.
	from += size + 1
	// Increment the loop variable....
	count++
}