def create
      ptr = ::FFI::MemoryPointer.new(:pointer, 1)
      self.class::Klass.create(ptr)        
      @handle = ptr.get_pointer(0)
      true
    end
def create
      ptr = ::FFI::MemoryPointer.new(:pointer, 1)
      self.class::Klass.create(ptr)        
      @handle = ptr.get_pointer(0)
      true
    end
Create a pointer for this Device handle .. must be called before open or anything else.
 Called automatically when objects are instantiated in block form.