+}
+
+/**
+ * gtk_tree_sortable_set_sort_func:
+ * @sortable: A #GtkTreeSortable
+ * @sort_column_id: the sort column id to set the function for
+ * @sort_func: The comparison function
+ * @user_data: (allow-none): User data to pass to @sort_func, or %NULL
+ * @destroy: (allow-none): Destroy notifier of @user_data, or %NULL
+ *
+ * Sets the comparison function used when sorting to be @sort_func. If the
+ * current sort column id of @sortable is the same as @sort_column_id, then
+ * the model will sort using this function.
+ */
+void
+gtk_tree_sortable_set_sort_func (GtkTreeSortable *sortable,
+ gint sort_column_id,
+ GtkTreeIterCompareFunc sort_func,
+ gpointer user_data,
+ GDestroyNotify destroy)
+{
+ GtkTreeSortableIface *iface;
+
+ g_return_if_fail (GTK_IS_TREE_SORTABLE (sortable));
+ g_return_if_fail (sort_func != NULL);