the GApplication
class uses GDBus, which reliably works on Linux, *BSD, Windows, and MacOS X.
on Windows, the first connection to the session bus using the GDBus API will result in a new process spawning a GDBusDaemon
instance; the address for the newly created session bus will be stored inside a named mutex, and all new processes requiring that mutex will be able to connect to the same session bus. this way it's possible to reuse the same mechanism of acquiring a name on the session bus on all platforms.