Reference Manual - 1.0.0
IDirectFB   EnumDisplayLayers

Enumerate all existing display layers.

EnumDisplayLayers (
  IDirectFB   * thiz,
  DFBDisplayLayerCallback   callback,
  void   * callbackdata
);

Calls the given callback for each available display layer. The callback is passed the layer id that can be used to retrieve an interface to a specific layer using IDirectFB::GetDisplayLayer().