Questions tagged [transaction-input]

Questions about the mechanics of redeeming a UTXO in an input script.

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Is it possible to retrieve input addresses of bitcoin transactions from raw blk.dat files?

I'm developing a script that processes blk.dat files from bitcoin core. So far, I am able to retrieve the following attributes for transaction inputs: "vin", "index", "...
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How do I determine whether an input or output is segwit? - revisited

This is a discussion that has already been had here, but bear with me. We're gonna be talking about tx faae7e55db14a32e083cbf6a91db8a5ab6a3b05e050d9cefdec80b47f966848e all I got is the encoded ...
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Is there software that can scan for reused R-values?

Is there any up-to-date program that can check for reused R-value for a specific Bitcoin address? (I don't want to scan the whole blockchain, just for a particular address.)
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1 answer
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How to interpret vin/vout on a Bitcoin transaction?

I used nownodes api to get this response on a transaction: ( [txid] => 38ac1348219f8aa9349f497bfa6f8d05f775cafbbd26354867d22ca84f15e1e1 [version] => 2 [vin] => Array ( ...
1 vote
1 answer
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How is a Bitcoin transaction signed using ECDSA?

I am quite familiar with the way secp256k1 ECDSA works as well as the equations that are utilised. However, I have no idea how this ECDSA applies to signing Bitcoin (SegWit Format) and transferring it ...
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3 votes
1 answer
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How do you commit to the previous output's amount when signing a segwit input with rust-bitcoin?

I'm trying to sign a segwit transaction in rust-bitcoin. To start with, my transaction setup looks as follows: let previous_output = OutPoint::new(Txid::from_hex("...
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2 votes
1 answer
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Segwit includes the input amount in the SignatureHash. What possible attack can this prevent?

Legacy transactions only include transaction components in the SignatureHash, but segwit transactions also add the amounts of inputs in the SignatureHash. Quoting from the Mastering Bitcoin Book: ...
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What is the script signature and PUSHDATA operation? [duplicate]

In bitcoin transactions, there is a part of the transaction known as the scriptSig. What does this mean? Also, what is the scriptSig (PUSHDATA opcode) operation.
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1 vote
1 answer
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Track the expenditure of an output with Bitcoin-qt via the REST API

How do you find the transaction whose input, vin, is a given output, vout? For example, the following is the JSON representation of the block with height 1000; here the mining reward is locked behind ...
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Invalid input scripts? Why are they included? Is there a correct way to identify them? [duplicate]

Transaction 88025f2bfa2435a7036a865ea0b4748491d21f9b8cfd72788e9d1c9aa8977e7d is valid, but its one and only input has an invalid script. (There are many transactions like this, but this one will ...
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2 votes
1 answer
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What is the weight of a P2TR input?

I'm looking for a detailed explanation of the weight, vsize and serialized length of a P2TR input, in the same vein as How big is the input of a P2PKH transaction?.
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What is the size and weight of a wrapped segwit single-sig input?

I'm looking for a detailed explanation of the exact weight, vsize and serialized length of a P2SH-P2WPKH (wrapped-segwit single-sig) input, in the same vein as How big is the input of a P2PKH ...
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0 votes
2 answers
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Why is the previous output index 4 bytes?

Using this post to define the format of a transaction: Create Output with a bunch of input Why is the previous utxo index (also called the previous output index) 4 bytes? The maximum output index ...
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Can I trace Bitcoin transactions using spent_transaction_hash?

I've spent some time analyzing Bitcoin transaction data and found out that the input column has this value called "spent_transaction_hash". In the dataset, the definition of this value is &...
0 votes
1 answer
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P2SH-Multisig transaction not going through

I have some funds locked in a testnet P2SH address which requires 2-of-3 signatures. This is the address: 2NEKRqUqoDtsELzpBa5wuWEiJeVbio5cSa2 and the 3 keys: #1 - ...
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1 vote
1 answer
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What exactly is signed in "prev_out"?

What is signed by scriptSig? I use my private key to sign data from the unspent transaction? I sign the "prev_out" object? I read that the signature in "prev_out" is there to ...
1 vote
1 answer
61 views

What is the exact size and weight of a 2-of-2 P2WSH input?

I'm proofreading an article mentioning the cost reduction of P2TR for Lightning channels in comparison to P2WSH. To that end, I'm looking for the precise weight, vsize and serialized length of a 2-of-...
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1 vote
1 answer
389 views

What is "Witness"?

What really is "Witness"? I saw this data in blockchain and can not identify what it really is. Here is the dump of transaction for example. TX hash = ...
1 vote
1 answer
23 views

How is the input and output fields serialised in a transaction?

I'm trying to write a parsing function to find the input and output fields in a serialised transaction. My problem is that I can find the number of inputs and outputs using the varint byte(s), but not ...
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Understanding transaction input and ouput

The definition of bitcoin transaction input and output that is there on the web is: Input = address from which money was sent, Output = address to which money is received 1. But when I looked at one ...
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Confused about input and output spending limitations and consolidation

I am sure the answer to this is trivial to someone who already knows the answer, but not to me. I recently wanted to spend some received bitcoin for the first time and discovered that the associated ...
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1 answer
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What does this Pubkey mean?

I just started learning about Bitcoin, and am sorta familiar with p2pk and p2pkh. I just found this input on a Bitcoin blockchain explorer: It looks like the Pkscript can be "solved" (I'm ...
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2 answers
42 views

How 1 address can create 14 inputs in output transaction to 1 direct address?

Check this address 1NM3apKLeDGKiFsd6gu1o4nh52efi38iEv The reason of this extremely high fee because of 14 inputs But why 1 address generate 14 inputs instead 1?
3 votes
1 answer
582 views

What is the size and weight of a P2WPKH input?

I'm investigating diverging P2WPKH input size calculations on two Bitcoin projects and some blog posts. I'm looking for a detailed explanation of the exact weight, vsize and serialized length of a ...
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3 votes
1 answer
630 views

How can the segwit witness data be "off-chain"? What does it really mean?

I have several questions regarding the segwit witness data. My current understanding is as follows. Before segwit, the witness data was part of the input that the user had to provide so that they ...
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194 views

How many addresses can be in input and output of a transaction

I have read through this question and i understand that there can be many sender and receiver addresses within 1 transaction(i'm new to bitcoin transaction, previous i was working with ethereum where ...
2 votes
1 answer
216 views

How is the UTXOs of each partially-spent TxIn determined?

My current understanding of a transaction is as follows: a transaction (Tx) can have multiple inputs (which are previous unspent transactions = UTXOs), let's call them the TxIn a Tx can have multiple ...
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Relation between transaction fees and inputs [duplicate]

So this might appear as a duplicate of some of the other questions on this stackexchange, but I feel most of the questions have failed to ask a question that I am really interested in. I want to ...
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1 vote
1 answer
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Is sharing a signed input safe?

Is it possible to decode the private key from a signed input? For example: From this signed input hex... ...
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5 votes
1 answer
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What are the sizes of single-sig and 2-of-3 multisig taproot inputs?

There was a Twitter discussion about the sizes of inputs and Taproot came up. What are the input sizes for Taproot inputs? Please cover both the key path spend (single-sig or default spend) and 2-of-...
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More Input-Values than necessary. How and why is this possible? No it is not the fees!

The TXID I am talking about: 21179a8560a0a0906f0c3396af338f74528130d46b65b7f0c79c378d343b3177 blockchain.com link: https://www.blockchain.com/btc/tx/...
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How to know where number of inputs field ends in a transaction if it is not a fixedsize field?

I know that we parse a transaction in bytes. So there are 2 quesions that I search for the answers of: 1- Can VarInt field -that gives the number of inputs in a transaction- be more than 2 hex digits(...
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How do I calculate the sum of transaction inputs?

I am attempting to calculate the mining fee of a transaction, given it's unsigned transaction hex by taking difference between the sum of the inputs and outputs. I also have access to an array of ...
0 votes
1 answer
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Is it possible to reference an input outpoint more than once in a transaction?

For example, could you have the following transaction: A --> B A --> C Where A is an input txid and index, and B and C are outputs? The reason I'm asking is because I believe with SIGHASH_SINGLE ...
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5 votes
2 answers
211 views

Can signature be re-used to cash out everything in the address?

I Know for the P2PK locking script it was like this [pubkey] <OP_CHECKSIG> and then an unlocking script is provided as simple as this: [sig] But if it works like this, others can simply grab ...
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1 answer
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Do transactions need to be signed

I always thought a transaction can be accepted when all its inputs are correctly provided with their unlock script (which usually contains a signature) ——yes transactions may also be rejected with ...
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1 answer
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Input of a transaction

If i want to send 0.2 bitcoin to Bob, will my transaction (in the input field) contain the list of all my previous transactions (both the ones in which i received bitcoins and the ones in which i sent ...
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1 answer
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Usage of PkScript as a part of Inputs of a Transaction

I've seen transactions with PkScripts as part of Inputs eg : Example of such a transaction Could anyone please explain how this PkScript is used ?
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1 vote
1 answer
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How to create a bitcoin transaction without inputs

How can I create a transaction without inputs and it will be broadcasted but of course won't get confirmed? I would like the simplest method to do this
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Can addresses used in a single tx be assumed to be from the same wallet?

can addresses of input of a single tx be always considered as belonging to same account? Above is a sample transaction on bitcoin. Here, input addresses are 3P2hJg8iRSBExAjd9yQGaazCLPFLeGB3hU (0....
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2k views

How to get input address and amount from vin using bitcoin core rpc

I am trying to find details of every transaction using bitcoin core rpc. First, I using bitcoin-cli getblock to get the block data, then use bitcoin-cli getrawtransaction to get the transaction ...
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1 vote
1 answer
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What does is mean to have input from multiple wallet addresses?

I've trying to parse some data from the blockchain as provided by blockchain.info My question is about transactions that have multiple inputs like this one: https://www.blockchain.com/btc/tx/...
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OP_EQUAL not working properly

I went to https://siminchen.github.io/bitcoinIDE/build/editor.html to try some bitcoin scripting and I wrote this script: <1PUzZ61FSVTn12CafJC85Vy1ts3BoFcXdU> OP_HASH160 <...
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805 views

How to manually sign a transaction with multiple inputs and multiple outputs?

I'm developing transaction constructor, but i faced several problems. To some of which i found answer in How to sign a transaction with multiple inputs?, for the rest i'll try to explain: When we ...
1 vote
2 answers
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What’s the purpose of checking for input overflow?

Everyone knows this famous fix for block 74638 which still exists in other files. But there’s something I can’t understand, why check for inputs overflow since it’s not possible to have enough utxo ...
4 votes
1 answer
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Maximum number of inputs per transaction

In theory, what is the maximum number of inputs per transaction? Is it defined primarily by the maximum number we can store on the 9 byte varint? How big of a number can be stored on 9 bytes? Would ...
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5 votes
1 answer
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Are all UTXOs locked by an address spent in a transaction?

Imagine I have 2 UTXOs locked by my address, each of which allows me to spend 5 bitcoins. If I subsequently want to send just 2 bitcoins to someone else, will both UTXOs be used as inputs in the ...
9 votes
2 answers
3k views

How do virtual size, stripped size and raw size compare between legacy address formats and native segwit?

This answer states that SegWit doesn't reduce transaction size. If this is true, why is it cheaper to send a SegWit transaction?
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2 answers
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Reference an UTXO of a transaction that has not been yet mined

How to reference an UTXO that has not been yet mined? I want to prepare a transaction and, before spreading it, use its UTXO as input for another relative timelocked transaction. Then, spread the ...
1 vote
1 answer
851 views

bitcoinj java library not decoding input addresses for some transactions

I'm trying to "extract" sender's addresses from OP_RETURN Bitcoin transactions, but my code is not working properly. getWalletAddressOfSender(final Transaction tx) public static Address ...
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