title: Windows HID Device Name Format
body: <p>There are various ways to retrieve the Windows "Device Name" of a HID device, <a href="http://msdn.microsoft.com/en-us/library/windows/desktop/ms645597(v=vs.85).aspx" rel="noreferrer">GetRawInputDeviceInfo</a> with RIDI_DEVICENAME being one way to do it.</p>
  
  <p>Given the example name:</p>
  
  <p>\?\HID#VID_FEED&amp;PID_DEAD#6&amp;3559c8ea&amp;0&amp;0000#{378de44c-56ef-11d1-bc8c-00a0c91405dd}</p>
  
  <p>I'm wondering if there is any documentation whatsoever on what is what in this string?</p>
  
  <p>\?\HID#VID_AAAA&amp;PID_BBBB#C&amp;DDDDDD&amp;E&amp;FFFF#{GUID}</p>
  
  <p>So the obvious ones are A(VID), B(PID) and the GUID on the end. What I'm wondering is what EXACTLY are C, D, E and F? </p>
  
  <p>It seems that C and D are unique even if you plug in two of the exact same HID devices which is great for my problem, but I'd feel more comfortable if I could know exactly how this is determined on a per OS basis, or at least that it follows some known format.</p>
  
  <p>I have been googling like a madman trying to figure this out, am I missing something obvious?</p>
  
  <p>Thanks in advance</p>