title: closesocket hangs
body: <p>I've been debugging for days and I have finally found something.</p>
  
  <p>My code for some reasons is blocking in <code>closesocket()</code> forever.</p>
  
  <p>Thats the reason all my IOCP threads were slowly dying...</p>
  
  <p>The debugger is showing that <code>closesocket()</code> call is frozen in 
  <code>NtWaitForSingleObject(0xXXXX, 0, 0);</code></p>
  
  <p>The socket in question is a UDP socket.</p>
  
  <p>The UDP thread which managed that socket has been force closed by <code>TerminateThread()</code>.</p>
  
  <p>Is there any reason for this to happen and anyway to fix?</p>
  
  <p>OS: Windows Server 2008 R2 Enterprise x64</p>
  
  <p>Language: C++ (With Visual Studio 2010)</p>