- * On return to io_loop, the connection will be closed. It doesn't have
- * to be the current connection and it doesn't need to be idle. No more
- * IO or callbacks will occur.
+ * The connection is immediately freed: it doesn't have to be the
+ * current connection and it doesn't need to be idle. No more IO or
+ * callbacks will occur, but if a function was added by io_set_finish()
+ * it will be called with the current errno preserved.