The model is simple. Each application using DCOP is a client. They communicate to each other through a DCOP server, which functions like a traffic director, dispatching messages/calls to the proper destinations. All clients are peers of each other.
Two types of actions are possible with DCOP: "send and forget" messages, which do not block, and "calls," which block waiting for some data to be returned.
Any data that will be sent is serialized (marshalled, for you CORBA fellows) using the built-in QDataStream operators available in all of the Qt classes. This is fast and easy. In fact it's so little work that you can easily write the marshalling code by hand. In addition, there's a simple IDL-like compiler available (dcopidl and dcopidl2cpp) that generates stubs and skeletons for you. Using the dcopidl compiler has the additional benefit of type safety.
An in-depth discussion of the motivation and usage of DCOP can be found in the KDE 2.0 Development book. Further information is available here. A tutorial is also available. DCOP's serialization format is formally documented.
Preston Brown [email protected]