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Due to complete lack of documentation on the subject, how would the pseucode for creating a transaction look using the following functions: createrawtransaction signrawtransaction and sendrawtransaction.
I receive the user transaction for incoming coins on IncomingTxID, when I create a raw transction I want to include at least some of those coins so if they won't confirm, neither will his payout.
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I am assuming you want to accomplish something akin to what SatoshiDice does. Here is how it can be done, using API calls with the Bitcoin-Qt/bitcoind client:
listunspent - you get the list of all unspent transactions
You determine which ones you want to spend
You use createrawtransaction to create your inputs / outputs, taking txid and vout from the list of transactions that you have that are playing, as well as a list of transactions that constitute a "money supply" for you.
Use signrawtransaction to sign the created transaction
Use sendrawtransaction to send the signed transaction
That should be pretty much it. I have implemented some of that code myself and it is pretty easy once you get a hang of it all.
7One bit of caution -- in the raw transaction, any inputs used that are not fully spent go to the miner. So be very careful when composing raw transactions. – Stephen Gornick – 2013-03-18T17:49:29.737
How about fee calculation? – Shamoon – 2013-07-29T14:12:45.107
@Shamoon http://bitcoinfees.com/ - you base them on the number of inputs and outputs.
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A good way to see this (and also a non-automated method to do this) is available through BrainWallet:
3One bit of caution -- in the raw transaction, any inputs used that are not fully spent go to the miner. So be very careful when composing raw transactions. – Stephen Gornick – 2013-03-18T17:50:41.437
How to do this is documented in Mastering Bitcoin (1st ed.), §"Using Bitcoin Core’s JSON-RPC API from the Command Line", §§"Creating, Signing, and Submitting Transactions Based on Unspent Outputs".
– Geremia – 2017-11-28T19:53:19.737Related: C# API for Bitcoin
– goodguys_activate – 2012-11-26T17:37:21.227