Specifies the type of the module initialization function. If a module contains a function named g_module_check_init() it is called automatically when the module is loaded. It is passed the #GModule structure and should return null on success or a string describing the initialization error.
Specifies the type of the module function called when it is unloaded. If a module contains a function named g_module_unload() it is called automatically when the module is unloaded. It is passed the #GModule structure.