<html><head></head><body>Excuse me, yes, for previously-signed transactions this is required. We might consider some limits on UTXO-chain-from-before-the-fork-length and likely something like move towards only allowing one transaction per block from the old mode over time.<br>
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I highly disagree that compatibility with existing transaction signing software should be considered (but for hardware which cannot be upgraded easily we do need to consider it). Wallets which can upgrade should, as much as possible, upgrade to a new form to maximize chain divergence and are going to end up having to upgrade to know a new header format anyway, so am extra few lines of code to change a transaction version should be trivial.<br><br><div class="gmail_quote">On January 26, 2017 12:21:37 PM EST, Gavin Andresen <gavinandresen@gmail.com> wrote:<blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
<div dir="ltr"><div class="gmail_extra"><div class="gmail_quote">On Wed, Jan 25, 2017 at 10:29 PM, Matt Corallo via bitcoin-dev <span dir="ltr"><<a href="mailto:bitcoin-dev@lists.linuxfoundation.org" target="_blank">bitcoin-dev@lists.linuxfoundation.org</a>></span> wrote:<br /><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div id=":1m6" class="a3s aXjCH m159d8d262b0da180">To maximize fork divergence, it might make sense to require this. Any<br />
sensible proposal for a hard fork would include a change to the sighash<br />
anyway, so might as well make it required, no?</div></blockquote></div><br />Compatibility with existing transaction-signing software and hardware should be considered.</div><div class="gmail_extra"><br /></div><div class="gmail_extra">I think any hard fork proposal should support a reasonable number of reasonable-size old-sighash transactions, to allow a smooth transaction of wallet software and hardware and to support anybody who might have a hardware wallet locked away in a safe deposit box for years.</div><div class="gmail_extra"><div><br /></div>-- <br /><div class="gmail_signature" data-smartmail="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div dir="ltr"><div>--<br />Gavin Andresen<br /></div><div><br /></div></div></div></div></div></div>
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