Synchronously flushes connection. The calling thread is blocked until this is done. See g_dbus_connection_flush() for the asynchronous version of this method and more details about what it does.
a gio.Cancellable or NULL
TRUE if the operation succeeded, FALSE if error is set
GException on failure.
2.26
Synchronously flushes connection. The calling thread is blocked until this is done. See g_dbus_connection_flush() for the asynchronous version of this method and more details about what it does.