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8 votes
Accepted

If you have the required mining power, is it possible to mine your transaction in the next block without propagating it to the network?

Yes, since miners (pools) construct the blocks they mine, they can insert any valid transactions they want, including transactions that were never broadcasted to the wider network. They don't even ...
Vojtěch Strnad's user avatar
8 votes
Accepted

What is the circular dependency in signing a chain of unconfirmed transactions?

What is the circular dependency here if only tx1 depends on tx0? Since tx1 depends on tx0, the txid of tx0 must be known before tx1 can be created and signed. However the legacy transaction format (...
Ava Chow's user avatar
  • 70.9k
7 votes

Block Health at 94.82%, why do nodes accept this?

Why do Nodes accept blocks that have so many intentionally excluded transactions? Because nodes do not get do discriminate between blocks. If a block follows the consensus rules, it must be accepted. ...
Pieter Wuille's user avatar
7 votes

I messed up? Am I saddled with a $2000 tx fee?

There's no feerate that you must use other than greater than the minimum of 1 sat/vbyte. You can choose to pay a lower feerate if you are willing to wait a bit. However, the feerates that you show are ...
Ava Chow's user avatar
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6 votes

How does node discovery and miner discovery work?

I am wondering how nodes discover other nodes Nodes learn about other nodes through: DNS seeds (which run crawlers that maintain databases of network nodes) From their peers (nodes gossip IP ...
Pieter Wuille's user avatar
6 votes

How to parse a raw transaction field by field?

This is one method to parse a bitcoin transaction manually, one level above the script level. Parsing a Bitcoin Transaction By Hand This tutorial follows the lessons taught by Base58 Bitcoin ...
Luciana Ferreira's user avatar
6 votes

Is there still a digital signature loophole in Bitcoin transactions?

Does the problem of repeating the value r still persist today in Bitcoin transactions? If your question is whether Bitcoin signatures are still vulnerable if their nonces are generated in a bad way: ...
Pieter Wuille's user avatar
5 votes

What will happen if I try to broadcast a transaction before the established locktime block height passed?

The transaction will not be relayed across the network and it will simply be as if the transaction never happened in the first place.
Ava Chow's user avatar
  • 70.9k
4 votes

Can someone explain nLockTime?

The locktime is a transaction field that can be used to prevent a transaction from being included in the blockchain until some point in the future. If every input’s sequence number is set to the ...
Murch's user avatar
  • 76k
4 votes
Accepted

How to differentiate between BTC transactions and BRC20 transactions on a blockchain?

How to differentiate between BTC transactions and BRC20 transactions Well, you can't because they are not disjoint sets, all BRC-20 transactions are also BTC transactions. You identify BTC ...
RedGrittyBrick's user avatar
4 votes
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How to build a transaction using bitcoinjs-lib

In P2SH, the output script is created by applying HASH160 (SHA256+RIPEMD160) to the redeem script, which is then revealed at spend time. So if you created the previous output, you should know what the ...
Vojtěch Strnad's user avatar
4 votes
Accepted

How is this transaction valid?

The signature is actually valid. The sighash is 8cc2772af5af61583c5a7ae89f777d3173afa470ce8b1bfa5f8d4b9a54635ccb and you'll find that the signature does indeed validate. So the question is how is this ...
Ava Chow's user avatar
  • 70.9k
4 votes
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Querying Non-Block Inclusion Evicted Mempool Transactions in Bitcoin Core >25.0

There is no RPC that can provide information about evicted/expired/conflicted mempool transactions. The reason these mechanisms exists is because the mempool is limited in size (configurable how much)....
Pieter Wuille's user avatar
4 votes
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Supposedly six OFAC sanctioned transactions were missing from blocks. Which transactions are these?

The answers to these questions are in the article linked in the tweet you're screenshotting: Which transactions is this user talking about? Their txids are: ...
Pieter Wuille's user avatar
4 votes

How to tell congestion info on the Bitcoin network?

There's really no such thing as "congestion" in Bitcoin. Rather, Bitcoin has a limit on how many transactions it can process, which is 1 block (1 MvB/4 MWU, around 2000-4000 transactions) ...
Vojtěch Strnad's user avatar
4 votes
Accepted

What could this OP_RETURN value be

The decoded OP_RETURN output OUT:D304E780755F46E62A42884421E39AF06342F0A4989704EE02989043769C4F93 matches the transaction identifier of the Ethereum transaction you mention first ...
Murch's user avatar
  • 76k
4 votes
Accepted

What happens if all transactions are being used?

A transaction ID is a 256 bit hash of transaction header data, so it is a 256 bit integer number. There can only be two to the power 256 distinct numbers that can be stored in 256 bits. Bitcoin now ...
RedGrittyBrick's user avatar
3 votes
Accepted

What fields of a coinbase transaction can be empty?

Would a block be accepted in which the coinbase transaction has an empty input scriptSig field? Is there an example of such? No, for unknown reasons there is a consensus rule that the coinbase input ...
Pieter Wuille's user avatar
3 votes

HOW TO SPEND P2SH with Redeem Script Hex?, Already make the transaction but still have some error

"scriptsig-not-pushonly" refers to the consensus rule that the scriptSig of a P2SH input must only include push operations (see BIP16). Your scriptSig not only includes opcodes other than ...
Vojtěch Strnad's user avatar
3 votes
Accepted

Trying to make SIGHASH_SINGLE transaction

I understand that second input can be not signed (really?). No, it can and still must be signed. The use of SIGHASH_SINGLE does not remove the need to produce a valid signature. The script ...
Ava Chow's user avatar
  • 70.9k
3 votes
Accepted

When the validity of scriptPubKey is checked?

If the transaction output scripts are only executed at the time they are attempted to spent, does it mean that in scriptPubKey (transaction output script) we can write whatever we want and its ...
Vojtěch Strnad's user avatar
3 votes

Block Health at 94.82%, why do nodes accept this?

Why do Nodes accept blocks that have so many intentionally excluded transactions? Bitcoin nodes do not implicitly discriminate against any nodes that are submitting new blocks and proper proof of ...
Poseidon's user avatar
  • 653
3 votes
Accepted

How to identify a transaction input type?

Looking at the transaction in raw (serialized) format, neither inputs nor outputs have their own type. In other words, it is not indicated anywhere what type they are. However, there are certain ...
dassd's user avatar
  • 1,099
3 votes

How to schedule a BTC transation in 3 years later?

Share a pre-signed transaction containing the appropriate nlocktime with the recipient.
Egg's user avatar
  • 111
3 votes

Bitcoin Core RPC for transactions of a new address without rescanning

You can rescan an address, or a bunch of addresses as defined by a range descriptor, using the scantxoutset RPC command. This will give you the current UTxOs paying to this (set of) address(es). ...
Antoine Poinsot's user avatar
3 votes
Accepted

Is it correct to say that "each transaction input is signed independently"?

You are correct, and the text is misleading. In general, every transaction input signature signs information from all over the transaction, including other inputs. This does not actually involve the ...
Pieter Wuille's user avatar
3 votes

I messed up? Am I saddled with a $2000 tx fee?

To add to the other answer: the size (and, thus, the cost) of your transaction depends on the number of inputs. Even though you might have sent the mining rewards to the same address, those ...
C-Otto's user avatar
  • 452
3 votes
Accepted

How do I find out who sent me Bitcoin?

In Bitcoin, it is generally not possible to attribute transactions to a single person without external knowledge of someone claiming that they made the transaction. There are no "from" ...
Ava Chow's user avatar
  • 70.9k
3 votes

What is the circular dependency in signing a chain of unconfirmed transactions?

In Bitcoin funds are tracked in the form of Unspent Transaction Outputs (UTXOs). When building a transaction you declare exactly which UTXO you are spending by providing the UTXO’s outpoint. The ...
Murch's user avatar
  • 76k
3 votes

Can a spend before a timestamp condition be put on a Bitcoin UTXO?

You can do this by creating a P2WSH output with the following script: OP_IF <condition 1> OP_ELSE <timestamp> OP_CHECKLOCKTIMEVERIFY OP_DROP <condition 2> OP_ENDIF Then ...
Vojtěch Strnad's user avatar

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