sync url session data task

main.swift

//
//  main.swift
//  test
//
//  Created by 張子晏 on 2017/6/3.
//  Copyright © 2017年 張子晏. All rights reserved.
//

import Foundation

let semaphore = DispatchSemaphore(value: 0)
let url = URL ( string: "https://www.apple.com" )!
let request = URLRequest ( url: url )
let task = URLSession.shared.dataTask ( with: request ) { ( data, response, error ) in
    let httpResponse = response as! HTTPURLResponse
    let statusCode = httpResponse.statusCode
    if (statusCode == 200) {
        print("Everyone is fine, file downloaded successfully.")
    } else  {
        print("Failed")
    }
    semaphore.signal() // releasing the resource
}

task.resume()
semaphore.wait()  // requesting the resource