The central concepts of D-Bus are modelled in a very similar way in dbus-glib and GDBus. Both have a objects representing connections, proxies and method invocations. But there are some important differences: dbus-glib uses libdbus, GDBus doesn't. Instead, it relies on GIO streams as transport layer, and has its own implementation for the the D-Bus connection setup and authentication. Apart from using streams as transport, avoiding libdbus also lets GDBus avoid some thorny multithreading issues. dbus-glib uses the GObject type system for method arguments and return values, including a homegrown container specialization mechanism. GDBus relies uses the #GVariant type system which is explicitly designed to match D-Bus types. The typical way to export an object in dbus-glib involves generating glue code from XML introspection data using dbus-binding-tool. GDBus does not (yet?) use code generation; you are expected to embed the introspection data in your application code.

dbus-glibGDBus#DBusGConnection#GDBusConnection#DBusGProxy#GDBusProxy#DBusGMethodInvocation#GDBusMethodInvocatoindbus_g_bus_get()g_bus_get_sync(), also see g_bus_get()dbus_g_proxy_new_for_name()g_dbus_proxy_new_sync(), also see g_dbus_proxy_new()dbus_g_proxy_add_signal()not needed, use the generic #GDBusProxy::g-signaldbus_g_proxy_connect_signal()use g_signal_connect() with #GDBusProxy::g-signaldbus_g_connection_register_g_object()g_dbus_connection_register_object()dbus_g_connection_unregister_g_object()g_dbus_connection_unregister_object()dbus_g_object_type_install_info()introspection data is installed while registering an object, see g_dbus_connection_register_object()dbus_g_proxy_begin_call()g_dbus_proxy_call()dbus_g_proxy_end_call()g_dbus_proxy_call_finish()dbus_g_proxy_call()g_dbus_proxy_call_sync()dbus_g_error_domain_register()g_dbus_error_register_error_domain()dbus_g_error_has_name()no direct equivalent, see g_dbus_error_get_remote_error()dbus_g_method_return()g_dbus_method_invocation_return_value()dbus_g_method_return_error()g_dbus_method_invocation_return_error() and variantsdbus_g_method_get_sender()g_dbus_method_invocation_get_sender()