title: Xcode 9 - Downloadable xip file is corrupt from apple site
body: <p>I have downloaded the new Xcode 9 build from the Apple website</p>
  
  <p><a href="https://developer.apple.com/xcode/" rel="noreferrer">https://developer.apple.com/xcode/</a></p>
  
  <p>However, I am getting the following error when extracting the file</p>
  
  <p><a href="https://i.stack.imgur.com/GzjPJ.png" rel="noreferrer"><img src="https://i.stack.imgur.com/GzjPJ.png" alt="enter image description here"></a></p>
  
  <p>Is this a known issue with the downloadable file or do I need to do something else in order to extract the <code>xip</code> file.</p>
  
  <p>My Mac config</p>
  
  <pre><code>High Sierra
  System Version: macOS 10.13 (17A352a)
  Kernel Version: Darwin 17.0.0
  </code></pre>