* children (recursively) before finally freeing the memory. It returns
* NULL, for convenience.
*
- * Note: errno is preserved by this call.
+ * Note: errno is preserved by this call, and also saved and restored
+ * for any destructors or notifiers.
*
* Example:
* p = tal_free(p);
* TAL_NOTIFY_FREE is called when @ptr is freed, either directly or
* because an ancestor is freed: @info is the argument to tal_free().
* It is exactly equivalent to a destructor, with more information.
+ * errno is set to the value it was at the call of tal_free().
*
* TAL_NOTIFY_STEAL is called when @ptr's parent changes: @info is the
* new parent.