   [C++ /DLLs] Events across DLL boundaries
  Though similar to this thread I want to ask this question in a different way.I would like to be able to raise an event in a dll that can consumed within an application that uses that dll without compiler dependency or whatever.  I'm sure this has been done many times before so what is your approach?I am unable to use the Windows message queue because it's likely neither application or dll would have a Window anyway.   
  Well, you could have your dll export a set of functions that in turn are used to set function callbacks. Each callback would be called when the associated event occured inside the dll.Another approach would be to use the Windows message queue via a  message only window. Your dll would export a function that would be called by the application to set the handle of the message only window. The dll could then send and post messages to the window which would be handled by the app specefied message handler.   