title: How to save kext configuration between sessions
body: <p>I am writing an OS X audio driver which will do some audio filtering. The driver kext is loaded on device connection and unloaded when device is unplugged. Driver configuration parameters are delivered via userspace application and can be changed during the device session.</p>
  
  <p>If the helper app is closed then the driver will use the last received parameters (or fallback to default). However, instead of using default configuration every time the device is plugged in, it would be nice if the driver would load and store its configuration on kext load/unload respectively.</p>
  
  <p>If I'm not mistaken, <a href="https://msdn.microsoft.com/en-us/library/windows/hardware/ff565537(v=vs.85).aspx" rel="nofollow">Windows uses registry for this type of thing</a>. I found <a href="http://lists.apple.com/archives/darwin-kernel/2003/Dec/msg00052.html" rel="nofollow">this</a> message dating from year 2003, in which this sort of behavior is discouraged, and the only way to do it is to introduce a daemon which will launch on boot and will look after the kext.</p>
  
  <p>Is there another (maybe easier) way to do the same thing 13 years later?</p>