title: Using System.Runtime.InteropServices but HandleRef is not found
body: <p>I'm trying to use Swig to wrap Raknet for use with Unity, but I can't build the generated C# files because I have 2,300+ errors saying:</p>
  
  <pre><code>The type or namespace name 'HandleRef' could not be found
  </code></pre>
  
  <p>From what I can tell, HandleRef is a struct in the "System.Runtime.InteropServices" namespace. However, I definitely have the statement</p>
  
  <pre><code>using System.Runtime.InteropServices;
  </code></pre>
  
  <p>at the top of the appropriate files. Additionally, I have mscorlib in my References.</p>
  
  <p>I'm extremely confused as to what's going wrong. Am I doing this wrong? Is there some factor I'm missing? How can I get this to build?</p>
  
  <p>(I'm using Visual Studio Express 2012 on Windows 8, if that makes any difference.)</p>