14     list_node_t *tail;  member
30     list->head = list->tail = NULL;  in list_new_internal()
104   return list->tail->data;  in list_back()
111   return list->tail;  in list_back_node()
126     if (list->tail == prev_node) {  in list_insert_after()
127         list->tail = node;  in list_insert_after()
145     if (list->tail == NULL) {  in list_prepend()
146         list->tail = list->head;  in list_prepend()
163     if (list->tail == NULL) {  in list_append()
165         list->tail = node;  in list_append()
167         list->tail->next = node;  in list_append()
168         list->tail = node;  in list_append()
185         if (list->tail == list->head) {  in list_remove()
186             list->tail = next;  in list_remove()
195             if (list->tail == node) {  in list_remove()
196                 list->tail = prev;  in list_remove()
215         if (list->tail == list->head) {  in list_delete()
216             list->tail = next;  in list_delete()
225             if (list->tail == node) {  in list_delete()
226                 list->tail = prev;  in list_delete()
241     list->tail = NULL;  in list_clear()