FSEventStreamCreateRelativeToDevice:如何获取deviceID的根文件夹？

import UIKit

let deviceID = UIDevice.current.identifierForVendor?.uuidString

let fileManager = FileManager.default
let documentsDirectory = fileManager.urls(for: .documentDirectory, in: .userDomainMask).first!
let rootFolderURL = documentsDirectory.appendingPathComponent(deviceID ?? "UnknownDeviceID")

// 创建一个名为"example.txt"的文件
let fileURL = rootFolderURL.appendingPathComponent("example.txt")
fileManager.createFile(atPath: fileURL.path, contents: nil, attributes: nil)

// 读取文件内容
if let fileContent = fileManager.contents(atPath: fileURL.path) {
    let contentString = String(data: fileContent, encoding: .utf8)
    print(contentString ?? "Unable to read file content")
}

// 删除文件
try? fileManager.removeItem(at: fileURL)