Description GIOExtensionPoint provides a mechanism for modules to extend the functionality of the library or application that loaded it in an organized fashion. An extension point is identified by a name, and it may optionally require that any implementation must by of a certain type (or derived thereof). Use g_io_extension_point_register() to register an extension point, and g_io_extension_point_set_required_type() to set a required type. A module can implement an extension point by specifying the GType that implements the functionality. Additionally, each implementation of an extension point has a name, and a priority. Use g_io_extension_point_implement() to implement an extension point. It is up to the code that registered the extension point how it uses the implementations that have been associated with it. Depending on the use case, it may use all implementations, or only the one with the highest priority, or pick a specific one by name. To avoid opening all modules just to find out what extension points they implement, GIO makes use of a caching mechanism, see gio-querymodules. You are expected to run this command after installing a GIO module.