data which is passed to func when this hook is invoked
the default @finalize_hook function of a #GHookList calls this member of the hook that is being finalized
flags which are set for this hook. See #GHookFlagMask for predefined flags
the function to call when this hook is invoked. The possible signatures for this function are #GHookFunc and #GHookCheckFunc
the id of this hook, which is unique within its list
pointer to the next hook in the list
pointer to the previous hook in the list
the reference count of this hook