return node;
}
+list_t *list_append(list_t *head, void *data)
+{
+ list_t *last = head;
+ while (last->next)
+ last = last->next;
+ list_t *node = new0(list_t);
+ node->data = data;
+ node->prev = last;
+ if (last) last->next = node;
+ return last ? head : node;
+}
+
list_t *list_remove(list_t *head, list_t *node)
{
list_t *next = node->next;