Return-Path: Received: from smtp1.linuxfoundation.org (smtp1.linux-foundation.org [172.17.192.35]) by mail.linuxfoundation.org (Postfix) with ESMTPS id 7974949F for ; Sun, 1 Oct 2017 20:44:27 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.7.6 Received: from zinan.dashjr.org (zinan.dashjr.org [192.3.11.21]) by smtp1.linuxfoundation.org (Postfix) with ESMTP id 18D94467 for ; Sun, 1 Oct 2017 20:44:26 +0000 (UTC) Received: from ishibashi.localnet (unknown [IPv6:2001:470:5:265:a45d:823b:2d27:961c]) (Authenticated sender: luke-jr) by zinan.dashjr.org (Postfix) with ESMTPSA id 81CB938A0070; Sun, 1 Oct 2017 20:43:23 +0000 (UTC) X-Hashcash: 1:25:171001:mark@friedenbach.org::rKtRU+ncghIUmfI0:bPklK X-Hashcash: 1:25:171001:roconnor@blockstream.io::EcArDCXSpRD6YidL:DHtM X-Hashcash: 1:25:171001:bitcoin-dev@lists.linuxfoundation.org::+An6+ywuxm9zx6Bs:dSQyd From: Luke Dashjr To: Mark Friedenbach Date: Sun, 1 Oct 2017 20:43:18 +0000 User-Agent: KMail/1.13.7 (Linux/4.12.5-gentoo; KDE/4.14.34; x86_64; ; ) References: <201710010113.30518.luke@dashjr.org> In-Reply-To: X-PGP-Key-Fingerprint: E463 A93F 5F31 17EE DE6C 7316 BD02 9424 21F4 889F X-PGP-Key-ID: BD02942421F4889F X-PGP-Keyserver: hkp://pgp.mit.edu MIME-Version: 1.0 Content-Type: Text/Plain; charset="gb18030" Content-Transfer-Encoding: quoted-printable Message-Id: <201710012043.18742.luke@dashjr.org> X-Spam-Status: No, score=-2.3 required=5.0 tests=RCVD_IN_DNSWL_MED, RP_MATCHES_RCVD autolearn=disabled version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on smtp1.linux-foundation.org Cc: Bitcoin Protocol Discussion Subject: Re: [bitcoin-dev] Version 1 witness programs (first draft) X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.12 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 01 Oct 2017 20:44:27 -0000 On Sunday 01 October 2017 8:39:11 PM Mark Friedenbach wrote: > What about an optional commitment to witness size in bytes? The value zero > meaning =A1=B0I don=A1=AFt care.=A1=B1 I would argue that it should be a = maximum however, > and therefor serialized as part of the witness. The serialization of this > would be very compact (1 plus the difference between actual and maximum, > with zero meaning not used.) Could just do SIGHASH_WITNESS_SIZE in addition to SIGHASH_WITNESS_DEPTH...