+1 for the new field, overloading fields with new meaning is definitely not a good idea. Something like nExpireAt with a block height sounds reasonable to me, but we need to document that the usual caveats with blockchain reorgs apply. On Wed, Aug 6, 2014 at 4:08 PM, Jeff Garzik wrote: > ...because nLockTime is the exact opposite of expiration. A locked TX > begins life invalid, and becomes valid (not-expired) after nLockTime passes. > > A new field containing expiration time would work. > > > > On Wed, Aug 6, 2014 at 10:44 AM, Tom Harding wrote: > >> >> How is eventual expiration of a tx that started life with an nLockTime in >> the future "breaking", any more than any other tx expiring? >> >> >> >> On 8/6/2014 6:54 AM, Mike Hearn wrote: >> >> We could however introduce a new field in a new tx version. We know we >> need to rev the format at some point anyway. >> >> >> On Wed, Aug 6, 2014 at 2:55 PM, Jeff Garzik wrote: >> >>> ...and existing users and uses of nLockTime suddenly become worthless, >>> breaking payment channel refunds and other active uses of nLockTime. >>> >>> You cannot assume the user is around to rewrite their nLockTime, if it >>> fails to be confirmed before some arbitrary deadline being set. >>> >>> >>> >>> On Wed, Aug 6, 2014 at 12:01 AM, Tom Harding wrote: >>> >>>> ... >>>> >>> >> If nLockTime is used for expiration, transaction creator can't lie >>>> to >>>> help tx live longer without pushing initial confirmation eligibility >>>> into the future. Very pretty. It would also enable "fill or kill" >>>> transactions with a backdated nLockTime, which must be confirmed in a >>>> few blocks, or start vanishing from mempools. >>>> >>> >> > > > -- > Jeff Garzik > Bitcoin core developer and open source evangelist > BitPay, Inc. https://bitpay.com/ > > > ------------------------------------------------------------------------------ > Infragistics Professional > Build stunning WinForms apps today! > Reboot your WinForms applications with our WinForms controls. > Build a bridge from your legacy apps to the future. > > http://pubads.g.doubleclick.net/gampad/clk?id=153845071&iu=/4140/ostg.clktrk > _______________________________________________ > Bitcoin-development mailing list > Bitcoin-development@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/bitcoin-development > >