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. What *can* happen and you must be aware of is duplicated transactions. Satoshi sort of assumed this could never happen because everything is hash based, 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 be able to process the older parts of the chain that have this. There is a BIP that covers the new rule. -- Want fast and easy access to all the code in your enterprise? Index and search up to 200,000 lines of code with a free copy of Black Duck#174; Code Sight#153; - the same software that powers the world's largest code search on Ohloh, the Black Duck Open Hub! Try it now. http://p.sf.net/sfu/bds___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] Self-dependency transaction question...
On Sunday, 13 July 2014, at 7:32 pm, Richard Moore wrote: P.S. If it is valid, another question; what would happen if a transaction was self-referencing? I realize it would be very difficult to find one, but if I could find a transaction X whose input was X and had an output Y, would Y be a new valid utxo, without being a generation transaction input? Even if you could find such a transaction that contained its own digest, and even if such a transaction were valid, it still couldn't conjure new coins into existence. The sum of the outputs must be less than or equal to the sum of the inputs (except in the case of a coinbase transaction). If a transaction were to spend its own output, then the input would be completely used up by the output, leaving no balance for a second output. -- Want fast and easy access to all the code in your enterprise? Index and search up to 200,000 lines of code with a free copy of Black Duck Code Sight - the same software that powers the world's largest code search on Ohloh, the Black Duck Open Hub! Try it now. http://p.sf.net/sfu/bds ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] Self-dependency transaction question...
I believe tx have to be ordered sequentially within a block. Also since a tx is referenced by it's hash, it's practically impossible to make a self referential tx. Aaron Voisine breadwallet.com On Sun, Jul 13, 2014 at 4:32 PM, Richard Moore m...@ricmoo.com wrote: Hey all, I'm working on the UTXO database for my Python implementation of bitcoind and have found a situation I did not realize was valid, but since it seems to be, had a quick question. If you look at block #546 the 4th transaction's first input uses its own block's 3rd transaction as an input. https://blockchain.info/block/5a4ded781e667e06ceefafb71410b511fe0d5adc3e5a27ecbec34ae6 My question is, would the other way be valid, that is, could the 3rd transaction of a block, use the 4th transaction from the same block as an input? Or are transactions processed strictly top to bottom? Thanks, RicMoo P.S. If it is valid, another question; what would happen if a transaction was self-referencing? I realize it would be very difficult to find one, but if I could find a transaction X whose input was X and had an output Y, would Y be a new valid utxo, without being a generation transaction input? .·´¯`·.¸¸.·´¯`·.¸¸.·´¯`·.¸¸.·´¯`·.¸¸.·´¯`·.¸(((º Richard Moore ~ Founder Genetic Mistakes Software inc. phone: (778) 882-6125 email: ric...@geneticmistakes.com www: http://GeneticMistakes.com -- Want fast and easy access to all the code in your enterprise? Index and search up to 200,000 lines of code with a free copy of Black Duck#174; Code Sight#153; - the same software that powers the world's largest code search on Ohloh, the Black Duck Open Hub! Try it now. http://p.sf.net/sfu/bds ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development -- Want fast and easy access to all the code in your enterprise? Index and search up to 200,000 lines of code with a free copy of Black Duck#174; Code Sight#153; - the same software that powers the world's largest code search on Ohloh, the Black Duck Open Hub! Try it now. http://p.sf.net/sfu/bds ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
Re: [Bitcoin-development] Self-dependency transaction question...
On Sun, Jul 13, 2014 at 10:25 PM, Aaron Voisine vois...@gmail.com wrote: I believe tx have to be ordered sequentially within a block. Also since a tx is referenced by it's hash, it's practically impossible to make a self referential tx. Correct. A TX will not reference a later TX in the same block (or itself). This would be a good invalid-block test to add to the test suite. Any volunteers? -- Jeff Garzik Bitcoin core developer and open source evangelist BitPay, Inc. https://bitpay.com/ -- Want fast and easy access to all the code in your enterprise? Index and search up to 200,000 lines of code with a free copy of Black Duck#174; Code Sight#153; - the same software that powers the world's largest code search on Ohloh, the Black Duck Open Hub! Try it now. http://p.sf.net/sfu/bds ___ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
