From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sog-mx-3.v43.ch3.sourceforge.com ([172.29.43.193] helo=mx.sourceforge.net) by sfs-ml-3.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1X73Pc-0002uy-HE for bitcoin-development@lists.sourceforge.net; Tue, 15 Jul 2014 14:08:56 +0000 Received-SPF: pass (sog-mx-3.v43.ch3.sourceforge.com: domain of hotmail.ca designates 65.55.111.76 as permitted sender) client-ip=65.55.111.76; envelope-from=pmlyon@hotmail.ca; helo=BLU004-OMC2S1.hotmail.com; Received: from blu004-omc2s1.hotmail.com ([65.55.111.76]) by sog-mx-3.v43.ch3.sourceforge.com with esmtps (TLSv1:AES256-SHA:256) (Exim 4.76) id 1X73Pb-0003Vm-B6 for bitcoin-development@lists.sourceforge.net; Tue, 15 Jul 2014 14:08:56 +0000 Received: from BLU170-W39 ([65.55.111.71]) by BLU004-OMC2S1.hotmail.com with Microsoft SMTPSVC(7.5.7601.22712); Tue, 15 Jul 2014 06:56:21 -0700 X-TMN: [TtLPDiRVUTZW2K1IrQuQA0u81L+kioBU] X-Originating-Email: [pmlyon@hotmail.ca] Message-ID: Content-Type: multipart/alternative; boundary="_6ee2a025-56d5-43bb-85ee-8b8474780adc_" From: Paul Lyon To: Mike Hearn , Richard Moore Date: Tue, 15 Jul 2014 10:56:20 -0300 Importance: Normal In-Reply-To: References: <35E6FF51-F9C4-4973-8489-B364E7C27C14@ricmoo.com>, MIME-Version: 1.0 X-OriginalArrivalTime: 15 Jul 2014 13:56:21.0739 (UTC) FILETIME=[8F25B3B0:01CFA034] X-Spam-Score: -0.5 (/) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. See http://spamassassin.org/tag/ for more details. -1.5 SPF_CHECK_PASS SPF reports sender host as permitted sender for sender-domain 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (pmlyon[at]hotmail.ca) -0.0 SPF_PASS SPF: sender matches SPF record -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [65.55.111.76 listed in list.dnswl.org] 1.0 HTML_MESSAGE BODY: HTML included in message X-Headers-End: 1X73Pb-0003Vm-B6 Cc: Bitcoin Dev Subject: Re: [Bitcoin-development] Self-dependency transaction question... X-BeenThere: bitcoin-development@lists.sourceforge.net X-Mailman-Version: 2.1.9 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 15 Jul 2014 14:08:56 -0000 --_6ee2a025-56d5-43bb-85ee-8b8474780adc_ Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable Thankfully those two duplicated transactions were never spent when they fir= st appeared. Because of that=2C I chose to not not add them to the UTXO at = all when they first appear. When the duplicates appear they get added to th= e UTXO successfully because the earlier=2C conflicting versions are not pre= sent. That way you can carry on assuming that all transaction hashes are un= ique=2C and enforce that rule over the entire blockchain. Date: Mon=2C 14 Jul 2014 13:18:22 +0200 From: mike@plan99.net To: me@ricmoo.com CC: bitcoin-development@lists.sourceforge.net Subject: Re: [Bitcoin-development] Self-dependency transaction question... Conceptually all transactions in the block chain lie on a single timeline. = The fact that we quantise that timeline into blocks is in many ways neither= here nor there - it's still a strict line. =0A= What can happen and you must be aware of is duplicated transactions. Satosh= i sort of assumed this could never happen because everything is hash based= =2C but forgot that duplicating coinbases is possible and at one point this= did happen. It was banned by a rule change afterwards but you still must b= e able to process the older parts of the chain that have this. There is a B= IP that covers the new rule.=0A= =0A= ---------------------------------------------------------------------------= ---=0A= Want fast and easy access to all the code in your enterprise? Index and=0A= search up to 200=2C000 lines of code with a free copy of Black Duck=AE=0A= Code Sight=99 - the same software that powers the world's largest code=0A= search on Ohloh=2C the Black Duck Open Hub! Try it now.=0A= http://p.sf.net/sfu/bds _______________________________________________=0A= Bitcoin-development mailing list=0A= Bitcoin-development@lists.sourceforge.net=0A= https://lists.sourceforge.net/lists/listinfo/bitcoin-development = = --_6ee2a025-56d5-43bb-85ee-8b8474780adc_ Content-Type: text/html; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable
Thankfully those two duplicated = transactions were never spent when they first appeared. Because of that=2C = I chose to not not add them to the UTXO at all when they first appear. When= the duplicates appear they get added to the UTXO successfully because the = earlier=2C conflicting versions are not present. =3BThat way you can ca= rry on assuming that all transaction hashes are unique=2C and enforce that = rule over the entire blockchain.

Date: = Mon=2C 14 Jul 2014 13:18:22 +0200
From: mike@plan99.net
To: me@ricmoo= .com
CC: bitcoin-development@lists.sourceforge.net
Subject: Re: [Bitc= oin-development] Self-dependency transaction question...

Conc= eptually all transactions in the block chain lie on a single timeline. The = fact that we quantise that timeline into blocks is in many ways neither her= e nor there - it's still a strict line. =3B
=0A=

What can =3Bhappen and you must be aware of = is duplicated transactions. Satoshi sort of assumed this could never happen= because everything is hash based=2C but forgot that duplicating coinbases = is possible and at one point this did happen. It was banned by a rule chang= e afterwards but you still must be able to process the older parts of the c= hain that have this. There is a BIP that covers the new rule.
=0A=

=0A=
-----------------------------------------------------------------------= -------=0A= Want fast and easy access to all the code in your enterprise? Index and=0A= search up to 200=2C000 lines of code with a free copy of Black Duck=AE=0A= Code Sight=99 - the same software that powers the world's largest code=0A= search on Ohloh=2C the Black Duck Open Hub! Try it now.=0A= http://p.sf.net/sfu/bds
_______________________________________________= =0A= Bitcoin-development mailing list=0A= Bitcoin-development@lists.sourceforge.net=0A= https://lists.sourceforge.net/lists/listinfo/bitcoin-development
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