texts: Is there an application or a site grouping addresses by user graphically?

texts:
Addresses can be grouped as belonging to the same user (or, better, same "account") by grouping together the addresses that participate as inputs to a single transaction, and doing it transitively. This has been done in the recent paper by Shamir and Ron, by some previous researchers and can be done by znort's parser. I know this is not 100 % accurate but I'm fine with it.

What I'm looking for is a site that displays the results of such grouping graphically, possibly with transactions between accounts as well.

I've read about such a site on bitcointalk.org, but I can't find the topic any more. I'm looking for the url of the (now possibly defunct) site or the bitcointalk topic describing it.


texts: How to create a cryptocurrency backed by an asset (say a fiat currency or physical commodity)

texts:
I want to create a cryptocurrency for use between myself and a collection of friends (as a proof of concept).

Assuming that I want to peg my cryptocurrency to (say) the Chinese Renminbi and the price of Wheat, what would be the steps in creating such a cryptocurrency?


texts: Bitcoin transaction stuck since almost 3 weeks

texts:
about 3 weeks before (06th December) I have send a bitcoin transaction from my Ledger Nano S to my Bitfinex account and until today (25th December) it still didn't get confirmed.
I have no clue why it takes so long as I am sure that I ticked the high fee.
The transaction is mentioned as an open deposit in my Bitfinex account already, but it had 0/3 confirms after 2 weeks, so I baught a paid accelerator service (https://pushtx.btc.com/) where I paid 80 USD and finally it started to get confirmed, but so far it has 416/3 confirms. How can I need so many confirms?

The TXID is: a3b9d2eef1305a845ebe4e1c0c5fe813f10dfbf7c6f39553a71ca829e885b5c0

I would highly appreciate if you guys could help me. Either it will be received on my Bitfinex account or back to my Ledger does not matter, I just want to have it somewhere since I am worried that I am loosing the BTC in the transaction.

Thank you guys in advance and I wish you a merry Christmas!


texts: Transaction taking a long time to confirm, now it doesn't even show up on Bitcoin Explorer

texts:
UPDATE: Electrum now says the transaction is "Local" and now I have an option to "broadcast", should I do that?
OP:
So, I'm trying to spend a small amount of bitcoin on a website (not relevant) and I send over 0.0010346 BTC with a fee of 0.0000543 BTC  ( 30.2 sat/byte ) and it's been almost 24 hours, and it still hasn't confirmed. The website stated it saw my payment, and will convert my BTC into balance once the BTC gets confirmed, and it's stressing me out because I'm afraid my BTC was lost somehow... I'm generally new to BTC so any help is appreciated.
The transaction used to show up on Bitcoin Explorer (blockstream.info) which is what my wallet (electrum) directs me do, and now it doesn't?!? Really stressing me. Transaction id is c4bea179e5e772b131c475f9030088b67dea5054a545713dc32458829fa61598


texts: How does the hash of a coinbase transaction differ for the same miner?

texts: Based on the format of a coinbase transaction described here: What is the format of the coinbase transaction?, I don't see how the all the coinbase transactions for a given miner do not all have the same hash assuming the miner was just using a single pubkey and the block rewards were the same. If they all have the same hash then when you spend one of them, you effectively use them all because that transaction hash has now been used as an input. Clearly that wouldn't make sense, so how are they ensured to be unique transaction hashes?


texts: Who were the Bitcoin maintainers before 2014? When did maintainers gain/lose merge access?

texts:
The Bitcoin lead maintainer and co-maintainers have merge access (i.e. they can approve changes to Bitcoin source code). We can see who the maintainers were since 2014:
https://github.com/bitcoin/bitcoin/blob/master/contrib/verify-commits/trusted-keys

Is this a complete/accurate list of maintainers since 2014?
Is there a list of when maintainers had merge access before 2014?


texts:
We're a Foundation with board members across various countries. We have some difficulty setting up a bank account. It's definitely easier to create a Bitcoin wallet, but we want more than that.

Here are some conditions:

We want to keep track and control funds without too much overhead.
We want unique addresses for each donation, so a e.g. multisig electrum wallet wouldn't be ideal.
We don't mind relying on a 3rd party service.
We don't have a bank account yet (so BitPay might not work for us).

What would be a good solution for us?


texts: What are some open source blockchain projects?

texts:
I was trying to build a blockchain to host my cryptocurrency.For that I was searching for some open source blockchain projects and I came across Best blockchain open source projects which mentioned names like :

Eris
MultiChain
HydraChain
OpenChain

I was concerned whether these projects allow you to build your own blockchain or they just let you build something like a Dapp on their blockchain?


texts: What is the actual reason for using boost:signals for few functions?

texts:
The src/main.cpp has RegisterNodeSignals and UnregisterNodeSignals to register the functions as boost signals as below:

void RegisterNodeSignals(CNodeSignals& nodeSignals)
{
    nodeSignals.GetHeight.connect(&GetHeight);
    nodeSignals.ProcessMessages.connect(&ProcessMessages);
    nodeSignals.SendMessages.connect(&SendMessages);
    nodeSignals.InitializeNode.connect(&InitializeNode);
    nodeSignals.FinalizeNode.connect(&FinalizeNode);
}

Let us pick InitializeNode as an example. The actual invocation happens in src/net.cpp which invokes the function defined in src/main.cpp:

GetNodeSignals().InitializeNode(GetId(), this);

I have the following question:

Why cannot we simply call this function? Why should we complicate with boost library and signals?
Has it got to do with performance of threads? If yes, then why only the 5 functions in RegisterNodeSignals


texts: Have I backed up my wallet sufficiently?

texts:
I'm trying to make sure I'm backing up my bitcoin wallet sufficiently. I only have about $60.00 worth, so I'm not looking for super secure encryption or anything. I just want to make sure I can restore my wallet if my computer crashes.

Anyway, I'm using MutliBit. I went to Tools -> Export Private Key.  I then selected a location on my network drive, added a password, and hit the export button.

If something happens to my computer, I could just redownload the multibit client and install it on another computer, and then use the Restore Private Key function and direct it to the file on my network drive to restore my wallet.  Is that correct?


texts: What prevents broadcasting of fraudulent transactions

texts: I see a lot of questions and articles about why someone can't generate fake coins, maliciously attack the network, and essentially security discussions focused on the generation and interception of coins.  With the blockchain being described as a ledger, what prevents someone from simply broadcasting a transaction moving a small amount (fractions) of coins from one account to theirs?  Or can coin movements only be originated from the source address?


texts: Why would Mt. Gox's Open Transaction method still require six confirmations?

texts:
When withdrawing using Mt. Gox, one of the checkboxes is marked "Open Transaction" and it shows that this requires "6 Confirmations".

This is used if you might be paying another Mt. Gox account but want it to go through the blockchain rather than as a transaction handled internally by Mt. Gox and thus no corresponding transaction in the blockchain is made.

Since the input for the transaction is coming from Mt. Gox's own wallet, there is no concern over double spending.  Why would Mt. Gox require six confirmations for these if the recipient is another Mt. Gox account?


texts: How do I still have connections without forwarding port 8333?

texts:
First of all, this isn't a problem I am having, I'm just curious how this works.

If you run your node with port 8333 open, you'll receive a large amount of connections after being online for a while.

If you run your node without port 8333, you still have connections, but it usually won't exceed around 7 connections.

My stupid simpleton logic tells me I should have no connections if that port isn't open, but that clearly isn't the case.

So my specific questions are:
How do I have any connections at all without using port 8333?
If it is using another port, why is the limit at 7?
The node still relays txs to peers, just less of them, so I'm assuming it is not a security issue?


texts: What is the relationship of ckeypool and ckeystore?

texts: In the source, there are ckeypool and skeystore. I wonder what is the relationship of them and why need both.


texts: What is the reference algorithm for validating a Bitcoin address?

texts:
I need to validate Bitcoin addresses in an application I'm developing; I have found various code samples for various languages (even on StackOverflow), but none specific for the one I am using (C#); also, all of those samples seem to come from volunteers around the world, but I've been unable to find an "official" reference algorithm for address validation.

This links explains how an address is generated, but even it has some dubious statements, like "this is the most commonly used Bitcoin Address format" at the end of the article; also, it doesn't explain how to actually validate one if you're not doing the address generation.

What is the official, reference algorithm for checking the validity of a Bitcoin address?

Of course, I'm only interested in syntactic validity; I don't care if the address was ever actually used, if it has any Bitcoin balance, or if the user really is in possession of the associated private key.

Please avoid code samples, as they are language-specific; what I'm asking for is a detailed description of the steps required for validation, so that it can be implemented in any language of choice.


texts: Let's say I have Blockchain wallet, and I want to use another andoid app, or other wallet. Can I do it? Will there be a fee?


texts:
Are Bitcoins truly untraceable or only pseudonymous to certain extents?

For example:

If somebody wants to buy Bitcoins with a Credit Card (e.g. through a third-party service) then they transfer them to a Bitcoin address.
After that they send them to a second third-party service, which allows them to International Bank Transfer them to a fiat currency.

Can the Credit Card company or any of the third-party services trace the transactions?
Which precautions could somebody take to make the transactions more untraceable and what are the pitfalls? (e.g. coin joins, coin mixing, etc.)


texts: How does the Bitcoin client check for double spend?

texts: When the Bitcoin client looks at the input of a transaction, it know the hash of the previous transaction from which the funds are coming, however then, how does it know that this output has not been spent already? Does it need to scan the whole blocklist for another transaction spending that same output? Isn't that very inefficient?


texts: Can I still claim the pre-fork BCC with a current balance of 0 from Bitcoin Core wallet?

texts: I had BTC in my Bitcoin Core wallet before the BCC fork, but I didn't claim the BCC before transferring my BTC to another wallet after the fork.  Is it possible to claim the pre-fork BCC even though my Bitcoin Core wallet balance is currently 0?  If yes, how do I go about claiming the BCC from my Bitcoin Core wallet?


texts: Does Bitcoin Core v0.17.0 run on native wayland?

texts:
I'm trying to run bitcoin core v0.17.0 on Wayland on Fedora 29. When I run bitcoin-qt I receive

  Warning: Ignoring XDG_SESSION_TYPE=wayland on Gnome. Use QT_QPA_PLATFORM=wayland to run on Wayland anyway.

Running with QT_WPA_PLATFORM=wayland yields

  QSocketNotifier: Can only be used with threads started with QThread

Is there a configuration change that will allow bitcoin core v0.17.0 to run on native wayland? Or what is the best way to provide a bug report to the core devs regarding wayland issues?


texts: Where in ~/.bitcoin are mempool and UTXO pools written?

texts:
Where in ~/.bitcoin are the two pools in question stored when their size grows above the size set by dbcache and maxmempool in bitcoin.conf.
Is UTXO pool written to such location at Bitcoin Core's shutdown?


texts: Why does Armory enforce a minimum transaction fee?

texts:
When I send coins using the standard bitcoin.org client I can set the transaction fee to 0.  However in Armory client there is a transaction fee of .0005 and you cannot override it to less.

I was under the impression that transaction fees were set by the user, and that the transaction fee determined the priority of your transaction on the network...so why does Armory force this?

In fact when I sent coins with fee of 0 via bitcoin client it went through faster than when sending the coins back with a fee of 0.0005 with armory...?


texts: Btc unconfirmed in recievers block chain wallet from last 9 days

texts:
I sent btc to the address on 27 th august 1PnNad5w5LDFuUudVMnrb7tAVP4U7jUHyr

But in his blockchain wallet it showing  still pending.
What to do now.suggest me please

txid cca36806a1fbad4738a15be7a0a3528af278501350d873f6f4577cd5d789322e


texts: Can two private keys generate the same (public) Bitcoin address?

texts:
I know that private key is generated randomly by wallet. Is it possible that wallet generate the same address which is used in Bitcoin?

In other words:
Given two private keys ka ≠ kb, is it possible that they both generate the same public Bitcoin address?


texts: Unable to establish connection to bitcoin using json and php

texts:
I'm newbie to bitcoins. Im trying to get the info, as much as I can.
I'm trying to get the information by using getinfo() method that is mention in api documentation.
The code i have tried is mentioned below.

   require_once('jsonRPCClient.php');
        $bitcoin = new jsonRPCClient('http://identifier:identiferpass@rpc.blockchain.info:443');
 print_r($bitcoin->getinfo());

I have googled it but didn't find the solution. I'm not getting what is the issue in the above code.

I just want to create a hello world connection. Any suggestions will be appreciated. Thank you


texts: Why do people burn Bitcoin or other cryptocurrencies?

texts:
Burning is the process of destroying some of your tokens.

In the old days, this was done by sending them to an unexistend (or at least unclaimed, as far as known) address. Nowadays, some cryptocurrencies provide special 'burn' calls that can be used instead (and are easier for other parties to prove by that the tokens were burnt).

But wy do people burn their Bitcoin or other cryptocurrencies?


texts: I have a Bitcoin ABC full node. How do I split off Bitcoin SV?

texts:
I have some BCH in a Bitcoin ABC full node, which is currently running 0.18.5. I want to obtain the corresponding Bitcoin SV without spending on both chains at the same time and losing the BSV. I am capable of running a Bitcoin SV full node, with the same or a different wallet. Is it safe to spend these coins as is, or is there some special process for splitting them?

Unfortunately I haven't been able to find any useful information online, other than "send it to an exchange" which I really don't want to do. Even bitcoincash.org has no useful information and seems to want to pretend that nothing significant even happened.


texts:
The Blob Vault is a part of the Ripple project.
What is it?

The project should get a reamdme.


texts: long time ago I changed my computer but I have bitcoin adress and privet key (13 words). Now how can I access my wallet ? (my wallet has Bitcoin core). Please help me


texts: Does IBB make money? Where does its earning come from?

texts:
Slightly off topic, but perhaps it is still marginally on topic because it's about a Bitcoin-oriented business:

IBB is an "Islamic bank, acting according to the Sharia (Islamic law), charging 0% interest on BTC loans".

Is it a profit-oriented business? A charity? Does it make money? Where do its budget come from? (I saw they're advertising on the Bitcoin forum today)

I know they issued some GLBSE stocks, that might explain the source of the money - are Muslims effectively "donating" to this bank by purchasing stocks?


texts: Using vanitygen To generate addresses for different cryptocurrencies

texts: I know how to use vanitygen but how do you determine the number that will correspond to the -X parameter for a different cryptocurrency? For example it is -X 30 for Dogecoin.


texts: Looking for Bitcoin/Crypto payment processor that will split payments (pay multiple people from sale)

texts: I'm looking for a crypto payment gateway that will allow me to accept payment for a product. It should support splitting the payment between multiple crypto wallets (multiple people).


texts: Self-hosted Bitcoin wallet for Linux with API?

texts:
I'm looking for some Bitcoin wallet software I can host locally on my Linux server that provides either an API or webhooks for detecting when Bitcoin transactions have completed. I also need a way to initiate transactions (i.e. tell the wallet to send Bitcoins to an address).

Does anyone know of anything? I know there is coinpunk, but I don't see anything about it having such functionality.


texts: Check when transaction was added to the mempool?

texts: I know how to check when a specific transaction was included in the block. But how do I check when my bitcoind node first saw it? I would like to estimate for how long the transaction stayed unconfirmed after it was broadcasted.


texts: New to bit coin use. I have noticed over the past few months that the exchange rate has ballooned from 13 to now 22 $ a coin, this presents a problem, prices are almost never adjusted to account for the massive inflation; how is the rate set and are there ways of getting bit coins  (I use spendbitcoins.com) are a fairer rate. I would also like to say that if inflation on the coins continues to rise it will put a lot of market places out of business.


texts: Does BitMinter not use CPU's for mining at all?

texts: I just started using BitMinter on several computers. They have decent GPU's that are detected and working fine, but I'd like to be able to use my CPU's also and I can't seem to find any method to enable it.


texts: Why is Bitcoin Core not asking me to enter the decryption key for my allegedly "encrypted" wallet.dat?

texts:
I created a wallet.dat with Bitcoin Core on a new PC. Then I encrypted it with the GUI menu.
When I reloaded that computer, I was shocked to see that Bitcoin Core did NOT ask me to decrypt/unlock the wallet.dat -- it just loaded it right back up. The only indication I got that it was encrypted was that the "Encrypt wallet" menu item was disabled/greyed out. Not even a small text saying: "This wallet is encrypted."
Obviously, this made me feel as if it was not encrypted at all. So, assuming that Bitcoin Core had saved some kind of decryption file on my other computer from which it auto-decrypts it or something, I transferred the wallet.dat over to my current computer, also running Bitcoin Core. Same thing there: the only indication that it's encrypted is that disabled menu item.
Nothing else. I'm able to read the labels and see all the receive addresses and everything. Since the wallet has no actual Bitcoins in it yet, I can't test to make a transaction, but hopefully, at least that will prompt for the decryption passphrase.
Is there something I'm missing? Why isn't encrypting a wallet.dat actually encrypting its data? Is this like that idiotic practice that WinZip/ZIP format used to do where you could see all the files and the filenames but just couldn't read the file contents without the password? I never understood the point of that, and I certainly don't understand the point of Bitcoin's encryption if all it does is prevent you from sending coins away, but still allow you to snoop on the labels and receive addresses and all that.


texts: Where can I get historic data series of cryptocurrency prices?

texts:
Where can I get a time series of (date, bitcoin price in USD).

Any suggestions?

UPDATE

I would highly appreciate JSON for better input into code.


texts: I'm interested in getting data on bitcoin adoption by country. Is there a way of mapping bitcoin addresses to countries of origination?


texts: Is there any useful documentation on using the MtGox API with node.js?

texts:
I have been looking for some help building a platform using node that works with the MtGox api. It seems easy to make request, but I am confused about how to pass a parameter.

Right now my code starts off like below. I can hit the server and get basic market data but I don't know how to do anything else....

request = require('request');

APIResponder = require('../libraries/apiresponder');

exports.market_data = function(req, res, next){
  request('https://mtgox.com/api/1/BTCUSD/ticker', function (err, response, body) {
    console.log(response);
    console.log(body);
    APIResponder.respond(res, response);
  });
};


texts: bitaddress.org paper wallet vs. single wallet

texts: After generating a single wallet (at bitaddress.org), the paper wallet option at the top shows a different public address?  Why is the public address different?


texts: Understanding BIP 143 [hash computation, lockTime, sequence number, witness format]

texts:
I'm trying to grasp some of the concepts presented in BIP 143. These are the things I'm stuck on:

(1) A new hash format is presented. This new format is used to create a hash, which when signed with a private key, acts as a signature for an input. If my transaction contains a mix of input types (e.g. P2PKH and P2WPKH, for example), and I'm signing the P2PKH input, do I still use the original hash format that was used in the past or shall I use this new format? It appears the new format is only used when signing the P2WPKH inputs, correct?

(2) In the past, I've always set lockTime to 0x00. Why is it set to 0x11 in the BIP 143 example?

(3) In the past, I've always set sequenceNumber to 0xffffffff. Why is is set to 0xeeffffff in the BIP 143 example?

(4)I can't quite figure out the format of the witness section. Clearly, there should be one entry for each input. And for the P2PKH input it's just set to zero. But what comes next? According to this, each entry consists of an integer indicating the number of "stack items for the corresponding txIn", and then each stack item consists of a size indicator and the payload of the stack item. But what are the stack items and what is their order? Presumably this is where I'd put my input script and signature, right?


texts: How does the wallet prioritise keypool addresses imported via importmulti?

texts:
I want to use importmulti to import 100 addresses from an xpub descriptor.

If I set keypool: true as one of the arguments the keys get added to the keypool.

How does the wallet prioritise which keys it generates when calling getnewaddress? Will it prioritise the imported addresses or do I have to request the imported address via the label argument in getnewaddress? What if I don't add a label argument to the importmulti command?


texts: Is it possible that two miners mine blocks with different headers because they include different transactions

texts: Ok, it's a yes or no question: miners can include different transactions in a block, so does that mean that they search for different nonces


texts: Print all states of getting from a random 256 bit private key to a corresponding encoded BTC address

texts:
I wonder if it is possible to print what's going on under the hood regarding the process of getting from a random binary number to a BTC address.

It will look something like this:

Input: a random 256 binary number

Output: print()

Printing all possible sequential states from that number to a BTC address.

PRIVATE KEY STATES

binary privKey [k] -> decimal privKey -> hexadecimal privKey -> WIF privKey

PUBLIC KEY STATES

decimal pubKey print(x,y) -> print K where [K=(x,y)] -> hexadecimal PubKey (A) -> print A=RIPEMD160(SHA2569(K))

It will help a lot of people interested in the details of creating BTC addresses, from the elliptic curve private to public key process (K=k*G) to the other encoding steps until the final address.

On GitHub and other places, .js or .py libraries just print the WIF key and the address, and sometimes the hexadecimal public key as well.

Thanks.


texts: What does the `gen` option in bitcoin.conf do?

texts: The gen option isnt copiously described in the sample bitcoin.conf file  ... does that mean that the daemon started up will attempt to mine for coins?


texts: anyone attempted a multiple p2sh(multisig) send (ideally using python)?

texts: I attempted to use pycoin to do a "create_signed_tx" in python, but had no joy: Do you think it might be technically possible to use spendables(UTXOs) from multiple source P2SH wallets in a single push to the network ? Anyone done this successfully yet(ideally using python)?


texts:
Blockchain miners calculate the hash of (block data + nonce value). They actually guess (are looking for) nonce in order to get hash staring with a defined number zeroes. (The number of required starting zeros in hash value define the difficulty of finding a nonce that fits - proof of work).

My question is do all miners guess/try nonces from the same pool or range (this way they actually non-efficiently test the same guesses many times) or they somehow split the pool of possible nonces among themselves in order not to try the same nonces multiple times?


texts: Bitcoin core stopped sync'ing (without downloading all the data). How can I make it resume the synchronization?

texts:
I am extremely new to this concept but just decided to try. Unfortunately I did not do my homework before playing with my money.
I bought some coins and I sent them to my Bitcoin core wallet (that I had just installed, knowing nothing about the fact that it needed to sync first). I realized that since it wasn't synchronized I would need to wait until it finished downloading all of the data for me to have access to that money.

the problem is that my bitcoin core just stopped downloading data with the loading bar still in the middle and it is no longer synchronizing.

How can I make my bitcoin core complete to download all the data?


texts: How can I find a Bitcoin private key that I saved in a text file?

texts:
I certainly saved my private key in a text file previously,
but I don't know where now.

Is there any way to recover my private key?


texts: If a hard fork occurs and is broadcast to the bitcoin network, is there any manual intervention for miners to accept the fork?


texts: Step by step example to redeem a P2SH output required

texts:
I have been following BIP16 in creating a P2SH transaction. I want to create a simple (one signature) P2SH. I am getting an error when trying to broadcast the tx. Error is 16:  mandatory-script-verify-flag-failed (Signature must be zero for failed CHECK(MULTI)SIG operation)
To be clear, I am not trying multisig. What I am doing can be best described as P2SH-P2PK, though I have not seen this term.
This is the only example given in BIP16, so this should work.
Here is what I have tried (testnet):
private key: BB2AC60BC518C0E239D5AF9D8D051A6BDFD0D931268DCA70C59E5992
public key: 039f53e45f8f18b8ed294378bda342eff69b2053debf27fbede7d2d6bd84be6235
(compressed)

redeemScript: [{pubKeySize,pubKey}] [OP_CHECKSIG]
21039F53E45F8F18B8ED294378BDA342EFF69B2053DEBF27FBEDE7D2D6BD84BE6235AC

redeemScriptHash: RIPEMD160(SHA256(redeemScript))
323D0E8A083E98010299109337850D05DD6157F7

p2shAddress: Base58Check(0xC4 + redeemScriptHash) (C4 for testnet)
2MwprvB9tUMtX4vK8zJK8K329fNu79CJgR7

The above address has two UTOXs on testnet:
UTXO1: e434a13cac79dc3d26e7279bff05c0f071a2df03e2ba6ca13c88f0e82dca9998:0
UTXO2: 9b4943e7ab5f4512e42c94254eb6aab4c6823ce06d4ff816b7ce4fda155a2571:0

I now want to spent both UTXOs and keep following outputs:
Out1: 2MwprvB9tUMtX4vK8zJK8K329fNu79CJgR7 34000000 Satoshis
Out2: 2N8hwP1WmJrFF5QWABn38y63uYLhnJYJYTF 100000000 Satoshis

I created the tx as follows:

Create unsigned transactions with all scriptSigs empty

For each input to sign, set its scriptSig to redeemScript: 21039F53E45F8F18B8ED294378BDA342EFF69B2053DEBF27FBEDE7D2D6BD84BE6235AC,   keeping other scriptSigs to empty.

Serialize the new tx and append SIGHASHALL bytes (0x01) in little endian 4 bytes

Double Sha256 above and sign resulting value. Add one byte 0x01 to signature to indicate SIGHASH_ALL. Let sig be the resulting value.

Set the scriptSig as:
[0x00] [{sigSize, sig}] [{pubKeySize, pubKey}] [OP_CHECKSIG]

I am assuming that the following scriptPubKey will be used:
[OP_HASH160] [{scriptHashSize, scriptHash}] [OP_EQUAL]
The following are the k, r and s values for each input's signature:
Input 1:
k = 98790447509501799195296257240616657470656053786701275200434341714298778299820
r = 96398386359095408146340664941016369169423137684113382189227162443480418477689
s = 62903510511574365450545635776206168644738316078298063260649088246548574249129

Input 2:
k = 109372172176680138721552873719725202562296645126925021083510279924852033069204
r = 105162394984132461723584277789901247831150698039237112243693144757926439529504
s = 62903510511574365450545635776206168644738316078298063260649088246548574249129

After this, I am getting the following error in bitcoind for sending the tx:
error code: -26
error message:
16: mandatory-script-verify-flag-failed
(Signature must be zero for failed CHECK(MULTI)SIG operation)

What am I doing wrong?
EDIT: Thanks to the answer by arubi, I found there were two issues with the above steps. First thing, I was doing wrong was not encoding the redeemScript as stack data. Second thing, I was doing wrong was putting [0x00] in scriptSig. After fixing that, Step 5 should be:

Set the redeemScript as [{pubKeySize, pubKey}] [OP_CHECKSIG]

Set the scriptSig as [{sigSize, sig}] [{redeemScriptSize, redeemScript}]


texts: Do most small miners join mining pools? Is "pay-per-share" the dominant approach?

texts:
Is it correctly understood that most individual/small miners join mining pools?

Is "pay-per-share" (or some variations thereof) the most popular mining pool approach, which means that the pool pays a miner a guaranteed payout depending on the hash rate provided by the miner? In other words, the pool absorbs all the risk from how much mining rewards the pool actually earns.

If 1-2 are true, then, for a given miner, the question whether to mine or not simply becomes a question of whether the cost of running the mining equipment and paying the pool fees is less than or greater than the current mining reward which depends on the current price of Bitcoin. Is that an accurate description?


texts: Lightning LND - Send Payment Both Ways Within Same Channel

texts:
Me and my friend are testing Raspibolt running LND 0.6 Beta. We noticed the following problem/limitation:

When I opened a channel with him, I could send him payments (via invoice) without any problems (direct connection). But when he tried to pay me (via invoice), the transaction tried to go through other nodes rather than going directly to my node. Then we closed the channel and tried the other way around. He opened a channel with my node and I could receive payments from him but I couldn't send him any payments directly. Transaction one again tried to go through other nodes.

Why is this happening?


texts: Why is it not possible to replay transactions?

texts:
What if a miner takes a transaction which is already on the chain and adds it to a new block to earn the fee once more?

Which mechanism prohibits replay attacks of this type?


texts: Why would a miner mine with a difficulty other than 'the' difficulty?

texts: Why would a miner mine with a difficulty other than the network difficulty? Both of these questions describe miners mining in such a way. What's the benefit of this? What even does it mean?


texts: Electrum Wallet How to use "Child Pays for Parent"

texts:
my transaction is here: https://blockchain.info/tr/tx/cb371b331e99eccb2d7447f4fe02417812ad066de21843fa156d4890e2cdf329
The reciever is a exchange wallet I don't know the reciever's private key.
it got stuck for hours and I need them immediately. I used electrum wallet for the first time and I have forgetten tick "replaceable". So now I can't change fee.
Once, I used "child pays for parent" property but now I couldn't see on electrum wallet. How can I unstuck it? or How can I use " Child Pays for Parent" feature ? I really searched for hours but I couldn't use it.

note: and I open for other answers.. for example how to stop braoadcasting transaction? is it possible?
This is the weakest side of bitcoin, I think :(


texts: Get public or private key from address with C-lightning

texts:
I'm studying Lightning network and I use c-lightning.
I can Get a new address with newaddr method, but I can't find private key.
My address is bcrt1qmckts70jsq2u5886lgcq2yn7xjmp97t09zlrg, how can I retrieve it's public key?
Where Can I find it's private key?
$ bitcoin-cli validateaddress bcrt1qmckts70jsq2u5886lgcq2yn7xjmp97t09zlrgj                                                              │
{                                                                                │
  "isvalid": true,                                                                                │
  "address": "bcrt1qmckts70jsq2u5886lgcq2yn7xjmp97t09zlrgj",                                                                            │
  "scriptPubKey": "0014de2cb879f28015ca1cfafa3005127e34b612f96f",                                                                       │
  "isscript": false,                                                                                │
  "iswitness": true,                                                                                │
  "witness_version": 0,                                                                                │
  "witness_program": "de2cb879f28015ca1cfafa3005127e34b612f96f"                                                                         │
}


texts: How can one estimate the difficulty change?

texts:
I understand that the difficulty is growing and think that it should be possible to estimate how quickly that happens. I would like to analyze the previous difficulty progression and feel that I then should be able to predict the change in difficulty for the next year.

Are there already calculators that predict the change in difficulty? Where can I find a chart that compares the Bitcoin price to the difficulty progression?


texts: Am I really understanding how the "Trezor Model T", and hardware wallets in general, work?

texts:
Getting increasingly paranoid about losing my coins, I've yet again (for probably the 20th time by now) went looking for hardware wallets. The only semi-reasonable one seems to be the two Trezors. All the others seem fishy/unreliable to me.
But as I read and watch and listen, it seems like even the "premium" Trezor Model T requires "OS support" and even to go to a webpage (not hosted on the device itself) to actually use it. Its operations are not at all self-contained in the device itself.
Up until now, I always had the idea that the Trezors (even the first model) is entirely self-contained, and only plugs into a computer in order to use its network capabilities to be able to send coins and update its data. (Of course, doing all the validations and verifications on the device, so it doesn't have to trust the network or the computer it's plugged in to.)
Actually, I vaguely had the idea that I would be able to buy one and then physically take it with me somewhere, without any computer around, and sort of "beam" any amount of my coins into another person's Trezor or even other hardware wallet...
None of this seems to be the case. Even the expensive model with the touch screen appears to be entirely reliant on the "host computer" to do anything besides storing the coins. I bet the special Trezor "coin control panel" webpage doesn't even support my browser (I don't run spyware), and who knows how long that will stay online? I don't want to rely on some company's website, or require special "OS support" for my hardware wallet. That's why it's a hardware wallet! For it to be stand-alone.
Am I missing something fundamental? Are there no "actual" hardware Bitcoin wallets which can do everything by themselves: send and receive coins without any computer? I don't even have wireless Internet at home, but most people apparently have, so I definitely expected it to be using "wifi" on its own, but this doesn't seem to be the case?!
I really tried to find this out by myself before asking.


texts: What are the contents of the wallet.dat file? What is Key pool, default key and reserve keys?

texts:
There is this https://en.bitcoin.it/wiki/Wallet simple explanation of the contents of a wallet.dat file from bitcoin-core/bitcoin-qt.

I have some questions about this:

What is the default key? Does this refer to the address is use by default for spending bitcoins? So, does it refer to the private key?
What are reserve keys? Are these the public/privte keypairs representing my addresses? But why reserve?
What is the Key pool? Is it a collection of addresses (i.e. private/public keypairs), and if so, why are they pregenerated, if I can generate a new address at any time with no cost?

So, if I have two addresses in use in my bitcoin-core client, does that mean, that I am using 2 keypairs from the keypool? And the others are just not showing yet in the user interface, but are already created?

What does the following sentence mean (it is refering to the key pool):

This pooling feature was added so backups of the wallet would have a certain number of keys that would be used in the future.


texts:
I set up MultiBit Wallet 0.5.13 with three wallets and bought 1BTC to practice with.

From Wallet 1 I moved .25BTC to Wallet 2,
then 0.1 BTC from Wallet 2 to Wallet 3.

Wallets 2 and 3 both have correct balances: There are 0.1499BTC in Wallet 2 and 0.1BTC in wallet 3 (the slight difference was caused by the transaction fee).

However, in Wallet 1, which should have about 0.75BTC, the client shows 1.6695BTC.

When I try to move 1.5BTC out of Wallet 1, it says there are not enough BTC to do that... but the "Balance" shows:  1.6695 in the balance box on the top left when I am on Wallet 1.

Any idea what is happening?


texts: Bitcoin RPC estimatesmartfee argument keys necessary?

texts:
I am attempting to use a PHP RPC Wrapper to connect to bitcoind for RPC API calls, estimatesmartfee, more specifically.

My question is, do I need to specify the argument keys, or just the values?

For example, the below is with just the values

public function getSmartFeeEstimate($blocks)
{
    $command = new \Nbobtc\Command\Command('estimatesmartfee', [$blocks, 'CONSERVATIVE']);
    $response = $this->client->sendCommand($command);
    $contents = $response->getBody()->getContents();

    return $contents;
}

or do I need to specify the keys as well, for example...

public function getSmartFeeEstimate($blocks)
{
    $command = new \Nbobtc\Command\Command('estimatesmartfee', ['conf_target' => $blocks, 'estimate_mode' => 'CONSERVATIVE']);
    $response = $this->client->sendCommand($command);
    $contents = $response->getBody()->getContents();

    return $contents;
}

Normally I would just try each one and see what the functions return, however, I am in regtest mode, and its returning the same thing for both, which leads me to believe that it's ignoring the arguments and just telling me its not working...

{"result":{"errors":["Insufficient data or no feerate found"],"blocks":2},"error":null,"id":null}


texts:
Have problem. Sorry duplicate. and still not understand works

And on Bitcoin-QT

PS im confused how to back that money ~_~(cancel it)


texts: What does the 'n' in nLockTime and nSequence stand for?

texts: I know what nLockTime and nSequence do, but I'm just curious about where the 'n' comes from. Thanks


texts: How does namecoin compare and contrast to bitcoin?

texts:
Possible Duplicate:
  What are Namecoins?

It seems to me, a bitcoin newbie, that namecoin is something entirely different but has some similarities.   I would like to hear it from the bitcoin community what they think of namecoin and what it seeks to accomplish.


texts: Parsing a SegWit transaction, what are stack items in witness data

texts:
For every input we can have multiple stack items, what do these represent?
As a reference this question is helpful

Are these defined here?
For eg. P2WPKH would have a signature followed by a pubkey, (so two stack items)


texts: Blockchain.info returns "None Standard Script Output" when submitting a transaction?

texts:
I dont know what is wrong

var insight = new Insight('https://insight.bitpay.com','livenet');
insight.getUnspentUtxos('1MkZVyKqNB5jpJDpfhp4TkDikFwdQM44he', function(err, utxos) {

if (err) {
        console.log('Error in getUnspentUtxos: ' + err);
    } else {
        console.log('utxos' + ' :' + JSON.stringify(utxos, undefined, 2));

        var transaction = new bitcore.Transaction()
        .from(utxos)
        .addData('pime')// Add OP_RETURN data.
        .to('1J4u97VGMz4GV7YFfRjtKLDchZ5zjiKLu4',15000)
        .fee(1000)
        .change('1AG1c1t3FAAEFdxmzm3wTg7XAnRGSwX5QA')
        .sign(privateKey);

        console.log(transaction.serialize());

        //console.log(transaction);

    }
});

This is the result: http://pastebin.com/raw.php?i=YNaHBcmU


texts: How to extract the signature of a transaction using bitcoinj

texts: I am trying to extract the signatures from a transaction. What is the best way to do this given a com.google.bitcoin.core.Transaction object I just received from the network?


texts: Will Bitcoin suffer from a mining Tragedy of the Commons when mining fees drop to zero?

texts:
One issue that I haven't seen clearly addressed is the possible Tragedy of the Commons in Bitcoin's future (see this answer). 40 years into the future, the only significant direct benefit for honest miners is transaction fees, as the block reward is almost zero.

The potential problem here is Tragedy of the Commons - it is possible that while the entire network will benefit from miners, the financial incentive for any individual honest miner to mine will be too small, so fewer miners "than necessary" will mine, leaving the network open to 51% attacks. In this scenario, the Bitcoin network will fall pray to frequent attacks and will effectively disintegrate. Also consider extensions like Open Transactions, that might make conducting transactions on the real Bitcoin network unnecessary for most users, who will flock to 2nd level networks and reduce the miner's rewards from TX fees even more.

As Bitcoin is being designed and promoted as a Future Proof system, people have tried to analyse the system's economic behavior in this future.

What analysis has been done on this problem? Is the problem likely to happen (speculative question, I know ... but back up your arguments)? If there is a likely problem in the current implementation, what are some possible way to adjust the protocol in the future to combat this problem?

Update - please see here, I described a possible scenario that leads to network insecurity because of this issue.

Update 2 - linking to a recent thread I created on the forum about this.

Update 3 - Added a wiki entry.


texts: Is the otherwise promising Ripple set to become a great currency fraud?

texts:
The Ripple system is really interesting, but on one point I can't help thinking part of it is a great scheme to make the founders (and OpenCoin) ridiculously rich. The reason that makes me wonder is that 100 billion XRP were initially created, and of these 20 billion are kept by the founders and 80 billion were given to OpenCoin (from their wiki). OpenCoin plans to give away some XRP, and sell some XRP, but it's not clear in what proportions or how much. No new XRP will ever be created, and the value of XRP will increase gradually as more people demand it for transactions (and XRP is the native currency of Ripple and will be the most convenient transaction medium inside Ripple). XRP also have intrinsic value in that they are strictly necessary to perform transactions, and because XRP used for transactions are destroyed the total amount of XRP in the system will decrease steadily.

So we have a system where the founders and OpenCoin have control over almost all purchasing power. Moreover, because of this, they can keep exchange rates of XRP as high as they like by keeping supply low. If Ripple would take off and be widely adopted, the founders and OpenCoin would get unimaginably rich because of the big shares in the fiat currency they created.

It makes me think of the famous quote: "Give me control over a nation's currency and I care not who makes its laws." It doesn't apply in full because the founders and OpenCoin won't create more currency, but owning all currency from the beginning will have the same effect over the foreseeable future.

So is this nothing more than a smart fraud that's incredibly big in scope? Are there any indications that the supply of XRP will get some kind of fair distribution?


texts:
How do i get the mtgox bid , current_volume or other things using Bitcoincharts API?

for example:http://api.bitcoincharts.com/v1/trades.csv?symbol=mtgoxUSD

gives you the latest trades...but what if i want only the bid value how would i do it using the url above?

thanks


texts: I have a 0.16.3 Bitcoin Core wallet running. I have incoming transactions allowed and I have lots of incoming connections. However, I fail to see my node on the map of Bitnodes; it says it's unreachable, also I have tried to appoint it as a trusted node to my Samourai wallet, and Samourai also fails to connect to my node.


texts: Duplicate r value for an address: only an issue for a multi-input Tx?

texts:
I've modified the r-scan Python code to look beyond the 50 Txs the Blockchain.info API usually returns.

My modifications take all the r values for my address and look for duplicates, but a commented out section of code makes mention of just checking the TxIDs which have more than one input script.

Is it only Txs with multiple inputs that are the problem?


texts: Why was giving someone else my 12 word backup a bad idea?

texts: I lost my bitcoin last night when someone on blockchain support asked me to tell them my 12 word backup in order to reverse my bitcoin transaction that was unconfirmed at that time. Finally, my balance remained zero. Can someone explain to me what happened? Is there any chance for me to recover my funds?


texts:
I want to understand how the mining process works so that I can code up my own bitcoin miner. Does anybody have pseudo code of a bitcoin miner that will help me achieve this?

Also, help with an implementation in C++ will be helpful.


texts: What software/hardware is required to mine with an FPGA?

texts:
I have been looking for a device that would allow me to mine Bitcoins without too much noise and heat. Something relatively small that I could keep in a shelf without worrying too much about it.

A rig with GPUs is too noisy so I looked into FPGAs, but I have no idea what these devices are. From what I understand, an FPGA is just a card (like a GPU) so I would still need to keep a computer on 24/7, right?

So do I need special hardware/software to connect an FPGA to my computer or does it work like a GPU?


texts: How does a transaction using a Bitcoin payment code BIP 47 look like on the blockchain?

texts: Having that payment code addresses are untracable, how does a transaction look like in a block explorer if someone sends a payment to a reusable payment code?


texts: Where on the web can I find out the current total blockchain size?

texts:
This question partially asked the same thing, but only got a response for viewing the size when you have the client installed.

I want to know the total blockchain size without having to install the client and download the blockchain.


texts: Is blockchain the only technology for p2p decentralised global network?

texts: Are there any p2p decentralised cross border network structure out there?


texts: How do you broadcast a transaction programatically?

texts: What is the best way to broadcast a transaction to the network programatically? I know that blockchain.info has /pushtx but I'm pretty sure it rejects XHR requests from external sources because of CORS.


texts: how to set the transactions fee using the RPC call?

texts:
I am creating the web wallet for the bitcoin , I want to allow web wallet users to set the transactions fee .

Is their is any rpc call available for setting the transactions fee (for setting transactions priority) ?


texts: v0.13.1 wallet - connect failed: Network is unreachable (101)


texts: Why is liquid so inactive and (according to statistics) not being used yet?

texts:
After years of development 3 Months ago Liquid (the side chain project) was announced. If you look at https://liquid.horse/ you can find the following statistics as of right now:

Sidechain Stats Genesis Block September 27, 2018 Sidechain
Transactions  3458
Sidechain Blocks  125344 / 223.9 MB
Expected / Missing Blocks 144622 / 19278 (15.38%)
Entry (peg-in) Transactions   96
Exit (peg-out) Transactions   30
Liquid Federation Wallet  25.26 BTC / $97,905 USD

125k blocks of which 97% are empty but with a memory footprint of 223 MB of data to store 3458 transactions within the sidechain seems pointless at this time.
When liquid was announced several exchanges and services announced to run a liquid Server.

Is it just taking time for those players to integrate liquid properly?
When will this take off?


texts:
I am giving this a try to see if I can do bitcoin mining. I took a Windows laptop and installed GUIMiner on it. I then connected to bitminter pool on http://mint.bitminter.com:8332 using my ID. When I click to start Mining, I get this message "ValueError: need more than 1 value to unpack". The summary then says "connection problems".

What am I doing wrong?


texts: Is there an easier way to run multiple altcoins in one service than operating each daemon?

texts:
I am interested how to operate multiple currencies in one service like modern trading platforms do: Cryptsy(496 trading pairs), Bittrex (328 trading pairs), Poliniex(172 trading pairs).

The only way I see is to install all the daemons of each currency, but maybe there is some other more easy solution.


texts: How to make Simplecoin's powerpool to support Litecoin Segwit?

texts:
I tweek the code transation.py  https://github.com/simplecrypto/cryptokit/blob/master/cryptokit/transaction.py#L150 add:

    if (self.default_witness_commitment is not None):
        data += b'\x00'
        data += b'\x01'

https://github.com/simplecrypto/cryptokit/blob/master/cryptokit/transaction.py#L173 add:

    if (self.default_witness_commitment is not None):
        combs = self.default_witness_commitment.decode("hex")
        data += b'\x6a'
        data += self.varlen_encode(len(combs)+4)
        data += b'\xaa\x21\xa9\xed'
        data += combs

to match the BIP141  :https://github.com/bitcoin/bips/blob/master/bip-0141.mediawiki#specification

However when I run it . I always getting
CoinRPCException: Block decode failed

Any expert could help on this problem?

Reference:
base on the proposal: https://litecoincore.org/ltc-segwit-pool.pdf
and some reference :https://github.com/thrasher/eloipool/commit/d488480c263c57a1e5151a6db3090d1413d3a054
https://github.com/zone117x/nodestratumpool/pull/115
https://github.com/UNOMP/nodemergedpool/pull/4


texts: Withdraw and wallet lock race conditions?

texts:
I'm working on a site that has wallet-like functionality in ruby/rails. I'm wondering the best way to process withdraws. My first inclination is to do something like this:

def process_withdraw
  client.wallet_passphrase(ENV['wallet_password'], 10) # unlock the wallet for 10 seconds
  client.send_to_address(address, amount) # send coins
  client.wallet_lock # re-lock the wallet
end

However, I'm concerned that with many concurrent withdraws I could run into race conditions. For example, if "Process A" unlocks the wallet and sends coins, but then "Process B" jumps in and unlocks the wallet but before it can send coins, "Process A" locks the wallet. So when "Process B" tries to send, the wallet is locked.

Is this a legitimate concern? Do I need to re-lock the wallet or is it safe enough to just wait for the 10 second timeout? Is it worth writing some sort of queue system for my client?

Thanks a lot in advance!


texts: Balance doesn't show up after import in multibit

texts:
I'm trying to import a private key that I exported from Blockchain, I import it, the right public key is created, but no transactions show up or balance?
I've imported a bunch of private keys. and this is the first time I've run into something like this.
Could it be the date? The key is exported in the right Bitcoin-QT format. What could it be?
How can I enable 0 confirmation spending? I want to use it between addresses that I use so I don't need to worry about double spending; I really don't want to alter the source code and all that.


texts: Online wallet for betting / customer profile?

texts:
I am looking for a system that provides users with the option to deposit and withdraw BTC to a generated address.

Basically something that works like https://primedice.com/play and https://dicecoin.io/

On top of this, perhaps there is an all-in-one bitcoin dice system?

Thanks!


texts:
The release page for Samourai Wallet 0.96.03 lists an APK hash but does not have a downloadable APK file.

From the available zip or tar.gz files how can I locate (or create) an APK file to compare against the hash listed in GitHub?


texts: So I've read this article about how to start mining, and I've started mining, now how do I stop mining? the article seemed to neglected that part..


texts: Can you use the same seed for normal BTC and Lightning wallets?

texts: If I generated 24 words from a Ledger Nano, can I import these to a lightning network wallet e.g. Eclair?


texts: what is the source of bitcoin for trading site like koinexcoinbase/etc...?

texts:
I understand sites like koinex/coinbase/etc.. credit bit coins when we try to buy bitcoins from them.

How do they (koinex/coinbase/etc..) get bitcoins to give it to users when they buy? are they doing mining and getting coins? or do they buy bitcoins from somebody who is mining ?


texts: What qualifies as proof of residency for AML in the USA?

texts:
I am in a unique situation of not owning or renting property and no need for utilities.  I've tried to contact several exchanges to find out what are all the acceptable forms of proof of residency, but none of them respond.  I don't want to send money until I am sure I can meet the AML requirements, but I can't figure out if I can meet them.  And I don't want to deal with exchanges that are not AML compliant.

Is there a definitive list of documentation?

EDIT:  It's been almost two weeks with no response from 3 different exchanges.  Is there really no list of acceptable standards?  Is it save to send money and just find out if they accept what I can provide?


texts: How to watch lots of wallet addresses for new bitcoin transactions?

texts:
I need to watch many wallet addresses for new bitcoin transactions as they enter new blocks. I also need this transaction data to make updates on my end

What are my options?


texts: Does ASIC miners leave a trace in the mining history of bitcoin?

texts:
I have a research interest in understanding the spread of innovation, and the adoption of ASIC machines in the Bitcoin mining community is particularly relevant.

Does ASIC machines typically leave a trace in the blocks that they mined? Would a particular type of machine leave such trace/record/identifier in the transaction record?


texts:
Maybe a simple answer

From what I can research so far

Is Eloipool the only public Server avaiable that is not parked or deprecated and that has support for the ASIC chips using stratum  ?

Is there any support for Non Linux based solutions ?

Thanks in Advance

(I can take it Doc give it too me straight) :S


texts: What are the alternatives to downloading the 6GB block chain?

texts:
I hail from a state where bandwidth is yet at a premium. Typical download speeds, in my experience as a dialup ADSL user, range from 10KBps up to 70KBps. Inclement weather may cause packet loss if not outright link failure. Over the last few months several ISP hereabouts have responded to service requests speaking of issues at the gateway.

Granted the issues I face are local but my intent here should be pretty clear - What are the alternatives to downloading the multi-GB (and growing!) block chain?


texts:
According to this post: What are the keys used in the blockchain levelDB (ie what are the key:value pairs)?

One type of the keys in leveldb of bitcoin is formed in the following way

  'b' + 32-byte block hash

I wrote the following code in go but I got "not found".

genesisBlockHash := "000000000019d6689c085ae165831e934ff763ae46a2a6c172b3f1b60a8ce26f"
hashBytes, _ := hex.DecodeString(genesisBlockHash)
keyBytes := append([]byte("b"), hashBytes...)
data, err := db.Get(keyBytes, nil)

Where did I do wrong? How can I add 'b' to the hash?

Tried a simple case:

  'R' -> 1-byte boolean ('1' if true): whether we're in the process of reindexing.

Go code

data, err := db.Get([]byte("R"), nil)

But I still got "not found". Why...

Tried file.

  'f' + 4-byte file number -> file information record.

I could get some data. I think the following code should retrieve the "blk00000.dat" block file information, right?

readFile(db, []byte{0, 0, 0, 0})

func readFile(db *leveldb.DB, file []byte) {
    data, err := db.Get(append([]byte("f"), file...), nil)
    if err != nil {
        log.Println(err)
        os.Exit(1)
    }
    // read data
}


texts: Is there any open source tool to verify segwit transaction without publishing it?

texts:
I have created below transaction:

020000000001016c6bb8dbaa1e6b25d1267487b22206275c90a5aa8c28eb3c3aa87c97d717cf460000000017160014b6f9a9a9f51190e22798f85983c4f53fab1385a4ffffffff01faba00000000000017a914d6894287b4a028cd75ee8649ea3d59dba76ee55487024730440220373a133c6cbb6086d3e6c7152b3dda362c54dd7b2cdee60f40b862bd4cc4e012022008f034ac4c955e78a33833e485590e7598a9a19cd2196901e2e6f4d147dac4030121029d7cf71205e62ff34ff56ccd695e073397bf3330879dad2d2ffeff703748feb800000000

This is P2SH-P2WPKH signed transaction created by my python program. My intention is to validate my code without loosing bitcoins in the process. I did not find an option in bitcoin-cli to validate it. If there is any open source bitcoin client or online tool i can use to validate it, it will help in my testing.


texts:
I was previously putting my bitcoins into btcjam, but as there are no longer any secured loans I was thinking about moving my bitcoins into something else that will generate some profit over time while keeping the bitcoins in circulation. Coinlenders.com looked promising except for

 This is a demo instance of the CoinLenders Bitcoin Bank Script. While this demo is fully functional, nothing is real, and nothing is an investment.

What have you been doing with your bitcoins other than spending them?

I would like something that is low effort, low risk. Low return is fine; I was planning on sitting on most of my bitcoins anyways.


texts:
I have read conflicting reports on whether Thailand declared Bitcoin illegal or not. What has happened and how did it affect Bitcoin commerce in Thailand?

To what degree are there restrictions? I.e. which out of the common actions (possession, personal transactions, mining, private trading and commercial trading) with bitcoin are illegal?


texts: Automatically close the bitcoin-qt when enable SSL for RPC

texts:
I Just try to enable SSL for bitcoin-qt RPC call. I follow the SSL on RPC
link to archive my target. But I am getting the following error and close the bitcoin-qt automatically.

I am using the bitcoin-qt 0.16.3


texts: Prevent rounding errors when displaying bitcoin values in javascript

texts:
What is the correct way to prevent Floating Point Precision errors when displaying bitcon values in javascript? I've seen many answers on the topic, but they all seem to have their drawbacks.

Here's what I've tried:

I've chosen to store bitcoin values in satoshis, then simply convert to float on the front end using simple math. Is this correct? I'm trying to avoid float precision errors. It seems to work as intended when testing with a calculator as reference, but I would love to know for sure.

var units = {

    // In satoshis
    coin: 100000000,

    format_to: function(val) {
        // 1 BTC = 10^8 Satoshis
        return (val / units.coin).toFixed(8);
    },

    format_from: function(val) {
        // Parse the string as float the multiply * coin.
        return (parseFloat(val) * units.coin);
    }

};


texts: Method not found when I use bitcoin-cli to generate blocks under regtest mode

texts: As the picture shows,I am really confuesd.


texts: How do you perform double-SHA-256 encoding?

texts:
The Bitcoin Protocol-specification gives an example of double-SHA-256 encoding.

  hello
  2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824 (first round of sha-256)
  9595c9df90075148eb06860365df33584b75bff782a510c6cd4883a419833d50 (second round of sha-256)

I've tried various SHA256 calculators and the first encoding matches no problem, but the second always resolves to

  d7914fe546b684688bb95f4f888a92dfc680603a75f23eb823658031fff766d9

I've also tried UPPERCASE and swapping the byte endianness.


texts:
Calling

https://blockchain.info/multiaddr?cors=true&active=15PFsB56YYXwXSW6byaxHXfgGz2ySWnDzN

I get a json response which I can not figure out if it has some sort of error or that I'm mistaken.

The response show results in transaction 1206412 = 0.01206412BTC added to balance 0BTC should get 1206412 = 0.01206412BTC, however we get balance = 1201206412 = 12.01206412BTC, I think it's error in blockchain.info api or could you explain how the balance is calculated.


texts:
I understand that a dar red line on Slush pool hash rate means a block has been discovered by the pool.

What does the blue line mean around 5AM?


texts: Problem using op_checksequenceverify (op_csv) with relative time flag

texts:
i have trouble in using op_csv. The spending condition is not match to my expectation.

FUNDING

Redeem Script Hex: 03010040b27576a91451d2a5e04d25ceaa86e600a6ec34bd24431c675d88ac
Redeem Script Asm: 03<010040> OP_CHECKSEQUENCEVERIFY OP_DROP OP_DUP OP_HASH160 14<51d2a5e04d25ceaa86e600a6ec34bd24431c675d> OP_EQUALVERIFY OP_CHECKSIG

P2SH base85 address: 2NFRizqW8XpNQm7nxYvFpYTvYsy3BqgsEx2 (bitcoin testnet3)

Based on my mentioned redeem script, i set time parameter as 1 along with OP_CHECKSEQUENCEVERIFY. Now my expectation is once blockchain confirms this TX, supposedly, miner will accept my spending TX after 512 seconds.

here is my funding tx
https://testnet.smartbit.com.au/tx/318462c4f6fef6e3c4fc58e8803c1ca43f20d162ca41d5c74f9e89725d8b300d

SPENDING

02000000010d308b5d72899e4fc7d541ca62d1203fa41c3c80e858fcc4e3f6fef6c4628431000000008b483045022100f995ccfb8ce2bda36c4ec0f37f067ee6c87c58043155b3a583da201ffaaa4db50220794d23e402b3f0a9579ab9bb8fbb573eba8cffed27542c162b629aa0f914b10d01210292dbb331c39d84611fbaa8e225d781ec50c2ed21fbf311bfeb869042f4b3e1781f03010040b27576a91451d2a5e04d25ceaa86e600a6ec34bd24431c675d88ac0100400001d40c0600000000001976a91451d2a5e04d25ceaa86e600a6ec34bd24431c675d88ac00000000

i set this TX's version as 2 and input's nsequence as 03010040. Now, i am waiting for blockchain to confirm my funding tx. Not so long, my funding tx was confirmed with date 2019-11-24T10:46:05Z. Now, I expect that 2019-11-24T10:46:05Z + 512 seconds = 2019-11-24 10:54:37 is time miner will accept my spending tx. As the result once my funding TX has been confirmed then i can spend immediately without any relative time restriction. ANYONE know what is happening?

here is my spending tx
https://testnet.smartbit.com.au/tx/a68a821e06c1156d5fe80f3662c941142ed2ce1a57e597ce05bf167bce21fe2d

P/S: i further test by changing time parameter in redeem script from 1 to 4 and 5, then the result is slightly match to my expectation.


texts: How do I create a new address in the Bitcoin-Qt client?

texts:
I am using a Mac and downloaded Bitcoin-Qt as my wallet, and it has "synchronised". However, I am unable to use this program to generate a new address. I click on "new address", and all it makes me do is enter an address and name it…

Is it safe to use a website like Instawallet to "create" an address for me, and then  use this address to receive coins with Bitcoin-Qt?

If two different people are using the same Bitcoin address, in a client like Bitcoin-QT, and if both receive money to the very same address, how will the network know who "owns" the bit coins associated to that address?

What is this "Private Key"? Is there a private key for every Bitcoin address? Where do I find it?

Lastly, if I want to sell my bitcoins, how does the "Private Key" play into all of this?


texts:
As of 2014, miners that successfully mine a block are entitled to 25 bitcoins.

Can miners refuse to receive those 25 bitcoins, thereby reducing the total number of bitcoins that will ever be mined?


texts: What languages can I write plugins for c-lightning in?

texts: I know that there's a Python library available for writing plugins for c-lightning. What would I need to do to for example use a JVM language like Scala?


texts: multiple deposits using the same address for investment

texts:
i am new to the bitcoin thin and i want to know if i can keep the same adress for send and recive some money.
I use multibit HD wallet.
Beyond the line is what the help of he investment party tells me but since i am new i do not realy understand.

– There is no registration — you are identified via your bitcoin address only.

– Do not use Shared coin transaction.

– You are able to make multiple deposits using the same address.

– Until your payment is confirmed in the bitcoin network (included into a block), it is not deposited and does not appears in the list of recent payments. It can take several minutes, sometimes up to one hour, to mark the transaction as confirmed.

please some help/advise.
thanks.


texts: Is it a bad idea to use a bitcoin wallet address in a domain name or URL?

texts: Aside from it forever being public and kind of marrying a business to a wallet.


texts:
I want a bitcoin cash ABC chain (BCHABC) testnet faucet.
Cause 15th Nov. onwards after a hard fork on bitcoin cash network existing bch faucets are not working. Even questions over here are also not upto the mark https://github.com/Bitcoin-ABC/bitcoin-abc/issues?utf8=%E2%9C%93&q=faucet


texts: What is #Hash in bitcoin from a layman's perspective?

texts: I am currently reading through the paper on bitcoin and being from a non IT background, I am unable to understand the use/function of hash


texts: How long a high-priority transaction takes to evaluate

texts:
I am missing something so far in reading this (excellent resource). I read the part about transactions for the most part, but I don't understand the actual code evaluation part, and how long it takes. So if you have a low-priority transaction (because of a low-fee), it could take "a long time" to run, or potentially never. If you have a high-priority transaction (high fee), then it will get run "quicker" or "with higher probability". My question is what actually is happening between the moment of a transaction being "created" and it being "added to a block". I wonder if your code is actually run before the transaction is actually added to the block and validated, or it's never run until fully validated. I wonder because this seems like a huge performance slow-down in resource-intensive applications, and I wonder what people do there.

Here it says:

  A new block, containing transactions that occurred since the last block, is "mined" every 10 minutes on average, thereby adding those transactions to the blockchain.

So my question then basically is, if your code doesn't evaluate until that 10 minutes passes, or when the code actually evaluates. Basically what happens between a transaction being created and when it is incorporated into a block.


texts: Multibit Classic Wallet broken - Ballence unspendable

texts:
I loaded in my multibit classic wallet the other day, into a fresh install with the intent of migrating it to multibit HD, however when i tried to spend some of this bitcoin, the transactions never chose to confirm. In fact blockchain.info shows them as pruned from database. It seems this has corrupted my wallet in some way as it shows my spendable balance as $0 when this is wrong, it's ~$130. How can i clear these bugged transactions and spend the rest of my coin? I don't care even if i have to loose the bugged transactions. I have tried resetting the blockchain transactions in multibit, and it's done me no good what so ever. This was all 3 days ago. I would try using bitcoin core to see if that would remove the fault except i don't really want to tie up 122 GB of space over this.

How can i fix/remove/ignore these transactions to spend the rest of my unaffected bitcoin? Or has the damn thing just wasted all my money?


texts:
Is there a maximum size for any given transaction?

I just created this tx:

http://blockexplorer.com/testnet/tx/194173dcc07b396433d5725abe76d52b10d42ebd3d1d10b465429f87fee12a52

and although it seems to get confirmed I would like to know if adding more inputs or outputs (and thus increasing its size) could result in an undesired outcome.

Similar question (that doesn't answer my question, though): What is the maximum size of a transaction?


texts:
When BTC is mined, it is sent to the BTC wallet. The duration of the transaction can be up to 24h for online wallets.
 Is the duration faster, when transferring BTC to a “cold wallet”?


texts: How can I know if the blockchain network is with all fake nodes.What if i create my block network with all my fake nodes to validate transactions?


texts: What other wallets can import Qt's backup .dat file?

texts: I've been using Bitcoin Qt on my work computer (my only working computer at the moment) but last week Windows 7 decided that the program's bypassing the firewall to download the blockchain was a security risk and blocked it from doing so. I'm not the network administrator and fiddling with the firewall settings I can access hasn't done anything. While it is absolutely possible that I am missing some obvious solution, I've given up on fixing this. what I'd like to do now is download another offline wallet - one that does not need the entire blockchain - and import my Qt backup. I've tried MultiBit & Electrum, neither of which seem to work (although, again, it is possible that I'm missing something). Is there another program I can use? Should I wait until my laptop is fixed and just re-install BTC Qt on that? Am I out of luck?


texts: Are There Abbreviations/Acronyms/Codes for Cryptocurrency Exchanges?

texts: I wonder if there are any abbreviations/acronyms/codes for exchanges like Cryptsy, Kraken, and Ccex. Similar to abbreviations as seen for coins in Bitcoin = BTC and Litecoin = LTC.


texts: How to exchange a cryptocurrency from an address that's not in a wallet

texts:
Possibly dumb question here (and first-time poster).

I have a Coinbase account with several different cryptocurrencies in it. I recently used ShapeShift to exchange ether (ETH) from my Coinbase wallet to Ripple (XRP).

To do this I generated an XRP address using http://ripplepaperwallet.com. Then, in Coinbase, I sent my ETH to a provisional address generated by ShapeShift, after which they immediately deposited XRP into my generated address.

Here's the question: how do I now spend or use that XRP address? I'm only now realizing it's not hosted by any wallet, so I have no idea how to spend it or exchange it. (I'm trying to get it into the Binance exchange, if possible.) I have both the private key and the address, so in theory I should be able to access the funds, right?


texts: How to get coin address balance from *coind server?

texts:
Im running *coind on my local ubuntu box.

I see that "*coind getbalance [account]" will get me the total balance of a user account. And thats good and that works fine.

How do I get the balance of a individual users wallet (assuming they have more than 1 wallet associated with their account). For example, I have Wallet 1 with 10 coins and Wallet 2 with 20 coins for a total balance of 30 coins. How do I check the balance of the individual wallet (wallet 1 or wallet 2)?

I dont see any commands to view an individual addresses balance.


texts:
Can someone please explain these fuzzy understanding?
I am trying to implement my proper demo application of blockchain, but now I discover that many concepts are not that clear..

1- how do miners in a network learn that there is a new transction added in one block? is there some party responsible for notifications or something? after getting this information, must a miner re-copy the whole blockchain to his local computer?

2- As I understand, mining is done on blocks in bitcoin. So if someone add a transaction to a valid block, does this mean that the block has to be re-mined?

3- finally who decide to create a new block? is there some conditions on the size of the block or is it unconditional unlimited process?


texts: HD Wallet Child Private Key Derivation Function

texts:
I was trying to understand the specs on CKD function from both the bip32 standard and Mastering Bitcoin book, I couldn't understand how a private key is derived from the left side of the extended key.

The book just says the right side becomes the chain code and the left side becomes the private key, after some research online I read someone using terms like tweaks and modulus n,  G which are confusing me since they were not mentioned in the book and not so much in the specification itself.

Please help me clarify on how exactly a private key is derived from the left side of output, and the relationship with all those non mentioned parts like the modulus n (Which  n?), tweak (??), multiply by G ( What's G?) since all these terms are not well documented.


texts: bitcoind validateaddress extended info.. somtimes there, somtimes not, why?

texts:
I have noticed sometimes ./bitcoind validateaddress [addr] produces an extended output, like this:

./bitcoind validateaddress mjYvqa4tC4oEC2ATQrcJh9Ux3CLcszW5J9
{
    "isvalid" : true,
    "address" : "mjYvqa4tC4oEC2ATQrcJh9Ux3CLcszW5J9",
    "ismine" : true,
    "isscript" : false,
    "pubkey" : "03ab4a26a0d577bb4dd5c46b49c1dd19a30a582a5b317f952e490eaac86564fdc0",
    "iscompressed" : true,
    "account" : ""
}

And other times, when I validate and address it looks like this: (why?)

./bitcoind validateaddress n3t74UDtWZtBSVbF5DLxm4ViFiU7rRY5gm
{
    "isvalid" : true,
    "address" : "n3t74UDtWZtBSVbF5DLxm4ViFiU7rRY5gm",
    "ismine" : false
}


texts: Physical objects on the blockchain as data?

texts:
I have been wondering about the company that stores diamonds via the Blockchain using it as a ledger to follow each diamond individually from where it is mined through the world. Each diamond has a unique 'passport' and so it is impossible for it to get lost or for it to enter the black market. Can anybody explain to me how this works in terms of how the information about the diamond is broken into categories in order for it to be fully described. Also, does a physical 'passport' travel with each diamond everywhere? Are these stored on a specific blockchain designed particularly for the diamonds?

Thanks


texts: If more than one coin did the "mini-blockchain" proposal, would that make the weaker coin vulnerable?

texts:
So, I was reading this paper as a proposal to the ever growing blockchain problem. In summary, it's security is provided without a full blockchain by having a proof chain with these fields:

Previous proof block hash
block header hash

Now this is all fine, but one problem I see is what if 2 coins were to adopt this scheme? If one chain was vastly more powerful than another, than an attacker could take the other blockchain and build fake transactions and blocks onto it and then introduce it to the weaker coin's peers. The peers would see it as having a higher overall difficulty/length and adopt it. Other than verifying the genesis block's hash and embedding it within the peer/wallet software, is there any other way to prevent this attack? The paper also mentions trimming extremely old proof blocks, but that doesn't appear to be possible to securely do if the genesis block could be pruned from the proof chain.


texts:
Let's say I generated some coins with a given address and I want to send a specific amount of coins to a specific addresses, and move the remaining balance to another specific address. I want to do it all using bitcoind and an RPC call. It would be easy if it wasn't for the variable fee, based on the size of the transaction; just calculate the difference between what is in the first address and what needs to be paid out, and send the rest to the other address.

Is there some way to set an address in bitcoind that is to receive all the change, or to get some information on what the fee for the given transaction should be?


texts:
I trying to script the launch of cgminer based on a crontab.

Using a crontab entry that fires up a bash shell script that launches cgminer. Running the script directly launches cgminer flawlessly. Running the script from crontab always give the "no gpus usable" error.

I have triple checked that all vars are set (DISPLAY, GPU_MAX_ALLOC_PERCENT, GPU_USE_SYNC_OBJECTS=1), that the paths are correct, etc.

The entry is in the crontab accessible when being (sudo -s).

Any clues on what could be wrong ?

Again, drivers and SDK are installed correctly as everything works correctly when I launch the script manually.

The script launches cgminer with a basic cmd :

cd dir_where_cgminer_is_stored
./cgminer -c /folder/myconfig.conf

Thanks


texts: How does IBLT_diff reveal the transactions that needs to be retrieved?

texts:
I understand IBLT (Invertible Bloom Lookup Tables) and as far as I know it is used to increase propagation speed by only sending the transactions to a full node that its missing instead of sending all transactions. In Gavin's specification it is mentioned that we do:

IBLT_diff = IBLT_new - IBLT_us

What I understand from this is that the full node checks and after comparing its IBLT with the miner's IBLT, the full node figures out which transactions are missing.
Then full node requests the transactions missing from the miner. Is this correct?
In the middle of the specification, it says that they are not using the full transaction hash and then it says that in order to prevent brute forcing it adds a salt to it. May I know why they are doing this and if so then how does full node know the transaction hash to request from if its truncated.


texts: What blockchain (or similar technologies) allow for "splitting" the network, offline?

texts:
There were a few ideas on how to make the blockchain hierarchical, and also splitting it to allow for splits.

Are there any proposed/non implemented ideas that accomplish this with Bitcoin or any technology?


texts: BIP70 who issues the transactions, wallet or payment_url server?

texts:
The BIP70 specs I'm reading confuse me about who broadcasts the underlying transactions to the bitcoin network. My reading seems to suggest that both the user's wallet and the server at the payment_url do.

Is that true, or is it the user's wallet unless a payment_url is specified in the payment request, in which case the server at the payment_url does?


texts: signrawtransaction is not a function on bitcoin core V0.17.1

texts:
I'm using npm bitcoin-core ^2.0.0 to get access to my bitcoind (v0.17.1 MAC)

My code:

let signedRawTx = await btcClient.signRawTransaction(rawTx, [], [privateKey], 'ALL');

I get an error message telling me that signrawtransaction is deprecated, use signrawtransactionwithkey instead.

My problem: I tried to mixed uppercase letters like this:

btcClient.signRawTransactionWithKey(...)
btcClient.signrawtransactionwithkey(...)
btcClient.signRawTransactionWithkey(...)
...

with always the same kind of error:

signRawTransactionWithKey is not a function...

In my text editor, I can see all the available functions for btcClient, signRawTransaction is in the list but nothing like signRawTransactionWithKey.
If I type help in the console of bitcoind, I can see signrawtransaction and signrawtransactionwithkey.

Any advice ?


texts: How can I measure the "health" of Bitcoin?

texts:
What are the metrics that matter when evaluating the overall "health" of Bitcoin?

What are the thresholds?

Specifically

Economic (e.g. velocity, days destroyed, market volume & beta)
Technical (e.g. rate of difficulty change, block size, tx fees, size of the chain)
Diversity of stakeholders (who are the market movers, large investors, what are their intents: profit vs stability)
etc.

Specifically, I'm trying to get an understanding of financial health of a system that proclaims to be superior to the one it's trying to replace (or compliment).


texts: What is the character limit for sending an Ardor message to another account?

texts: I'm sending a message on the Ardor blockchain to another account, but what is the message character limit?


texts: I'm trying to run Bitcoin on a weak computer, which client consumes the least resources?

texts:
I am running the standard client on a weak computer (Windows environment). It often is slow and unresponsive, and takes a noticeable chunk of the hard drive. I would want to replace it with some alternative client that offers the same functionality (mainly, running as server and supporting the standard Bitcoin API), while also consuming less system resources.

Which Bitcoin client consumes the least system resources and is the best fit for weak computers?


texts:
Usually, when some bad guy do something, he requests a payment using Bitcoins. Given that the demanded payment is not common, wouldn't be easy to trace the attackers when they retrieve the money back? Assuming that the bad guy wants to retrieve all the money.

For example:

A) X requests 1000000 BTC.

B) Y is monitoring all transactions and notice about a payment of 1000000 BTC to qwerty

C) Y reports to all banks about the address qwerty, as it looks suspicious due to that recent income.

D) X goes to Z to withdraw the money, but as Z knows about that address, it blocks the funds and call the police.


texts:
What happend if I share my private key with my partner? Can we spend bitcoins together without collisons from the same wallet?
Me and my friend are using BlockChain.info - what will happend when we import same private key? Can this destroy this wallet?


texts: salvagewallet is not in the Bitcoin Core Console

texts: I want to try the -salvagewallet command, but it is not in the console. What is the command line syntax?


texts:
Im a student at Sri Lanka institute of information technology and I am reading for cyber security BSc. I'm supposed to do a research project  with a group of four people within an year. We are preferring to do our research project in bitcoin domain.  We are supposed to come up with a software component which will address an existing issue in current bitcoin system. Please provide us with some opinions to come up with a valuable idea on our research project.
What is a good critical issue to address?
Any suggestions to address that issue?
Thank you.


texts: Dogecoin Core Wallet 1.10 - Help - Encrypt Wallet Option not available to allow staking

texts:
Help,

I am new to staking using crypto currency wallets.

I have download the Dogecoin Core Wallet 1.10 and the Encrypt Wallet Option is greyed out. How can I encrypt this wallet for staking please? I have other wallets for other crypto currencies that are all staking fine.

Thanks in advance.

Declan


texts: Is it possible for a decentralized currency to have untraceable transactions?

texts:
I have been reading a bit about Bitcoin recently and am fascinated with the project and think it has great potential.

However, one thing I think it needs in order to gain mass popularity is to make it so if you give someone your address they can't just go and see all of your previous transactions.

I know in Bitcoin one is supposed to create a new key for every transaction, but not many people will be willing to do that. I don't think most people care about having complete anonymity for every transaction they make - but in the case of Bitcoin if you don't care about that then the person can see your entire transaction log.

Would there be a way to have both? I am no expert in Crypto (obviously) but could you perhaps have one address (say your email address) and every time you use it the system generates a new hash-address automatically and sends that. So then if someone just knew your email address that you give people to pay you they could not see the transactions you made because your hash-adress that is in the blockchain is not directly linked to it.

This likely will not work but I am wondering if anyone else has thought about this? I think it is what is needed.

Any comments would be awesome!


texts: Does GNOME or KDE desktop enviroment matter, at running a BitcoinCore node?

texts:
I have just installed Debian 9 (my first linux OS), and I am now choosing my Desktop enviroment. I have doubts at choosing between GNOME and KDE.

I know that both are conpatible with BitcoinCore, but my concern comes from the UI differences. The KDE and Bitcoin Core UI are both runed by Qt and GNOME is runed by GTK.

Does this have any significance?


texts: Finding IP addresses of all bitcoin miners

texts: I understand that the transactions don't have any IP info in them but I am curious to know if it is possible to enumerate over list of all the IP addresses involved in mining?


texts: Delegating the creation of a transaction

texts:
This question might seem quite strange. but I am wondering if its possible to delegate the creation of a transaction to a third party, without having to trust them with your private key?

In the same way that with credit cards you can preauthorise a transaction, i'm wondering if its mathematically possible to do the same with bit coins. What I'm thinking of is having the client create the transaction, from the private key, and then forward the transaction to, and only to the authorising body. That way they would then hold a cryptographically secure transaction which at a later time if appropriate they could distribute to the rest of the bitcoin network.

so specifically:

Does this leave open the risk of that person double spending the same bitcoin?
Is there a mathematical window between the point when the private key is no longer required, and when the distribution process has begun.  (e.g.  adding it the current block?)
Has anyone solved this already?

Edit for clarity:

The key aspect is the ability for someone other than the person sending the bitcoin to 'hold the transaction' and at a later date to either forget the transaction (so it never left the original wallet) or to distribute the transaction, so it is accepted by the bitchain as having been transferred.

It would be required that the only trust that the sender needs to have is that the transaction holding place is trusted to either distribute or drop the transaction fairly.  In particular that they do not obtain access to transfer additional money later, or different amounts etc..


texts: Why does Bitcoin Core's API report the wrong amount of my wallet *while a transaction is being processed* (but not once fully confirmed)?

texts:
Note: For privacy purposes, I'm using made-up amounts here for the most part.
I had 0.0305 BTC in my wallet. I then made a transaction of 0.01 BTC.
My Bitcoin Core GUI immediately started saying: 0.0205 BTC, but the RPC API says 0.0105.
When it's confirmed/settled, the RPC API goes back to saying the same thing as the GUI: 0.0205.
This confuses me. Why does it temporarily show a smaller number in the RPC API compared to the GUI? If it has to do with the transaction fee, why does this not reflect in the GUI?
The "pending" amount in the GUI says 0.00000000 BTC, so it's not like that explains it either. It's not taking the "pending" amount into consideration in the API response. I use getbalance to get it: https://bitcoincore.org/en/doc/0.21.0/rpc/wallet/getbalance/
The difference between the before/after 6 verifications sum is 0.0128 BTC. I don't know if that tells you anything or if it's fixed each time. It's certainly not the transaction fee. All I know is that I've noticed this every time I've made a transaction in the last year or so. (Note: I'm not saying that this is some "new thing" -- only that I've only noticed it for that long, probably because I barely used to pay attention at all to how many BTC I had when they were worth so little.)
What can explain this?


texts: Will Schnorr Multi-signatures completely replace ECDSA?

texts:
I stumbled upon the fact that schnorr signatures will most probably replace the current ECDSA system in a future BIP.

Is it worth learning about ECDSA or this will become obsolete/useless/confusing knowledge ?

Or should I go straight into schnorr signatures, for example how will it impact a model like this


texts: Is it possible to reach same address in HD wallets?

texts: Is it possible to reach same address (same private key) with different mnemonics and different derivation paths in an implant based on BIP32,BIP39 & BIP44 combination?


texts:
I'm having issues starting dogecoind after compiling in ubuntu 12.04 x64 running in VirtualBox on win 7 ultimate x64

here's what i've tried from inside dogecoin/src after make -f makefile.unix:

sudo su
./dogecoind -server -listen -daemon -rpcuser=dogerpc -rpcpassword=dogerpcpw -rpctimeout=30 -rpcport=8334 -rpcallowip=192.168.1.* -rpcallowip=127.0.0.1 -testnet

and i get:

Error: To use the "-server" option, you must set a secure rpcpassword in the configuration file:
/root/.dogecoin/dogecoin.conf

so i do:

cd ~/.dogecoin
emacs dogecoin.conf

i save the following parameters:

rpcuser=dogerpc
rpcpassword=dogerpcpw
rpcport=8334
rpcallowip=192.168.1.*
rpcallowip=127.0.0.1
server=1
daemon=1
listen=1
testnet=1

i even chmod 777 dogecoin.conf to be sure everyone on God's green earth could access it so that wouldn't be a problem, but still the same error when trying to start up dogecoind

would much appreciate any help/tips!


texts: Which one is safer for a cold storage bitcoin-core or electrum?

texts: Since bitcoin core and electrum uses different method in generating the wallet (BIP39 & BIP32). I wonder which one is the safer option to use for cold storage?


texts:
Is there any Web API available for us to query Blockchain data in hex format?

The format should follow the standard (https://en.bitcoin.it/wiki/Block#Block_structure) structure rather than JSON.


texts: How can 6.10 ₿ be the average value of a Bitcoin transaction (lately)?

texts:
Number of Bitcoins sent in the last 24 hours: 1.84 million ₿.
Number of Bitcoin transactions in the last 24 hours: ~301,900.
This becomes on average 6.10 ₿ per transaction. That's shocking to me. Since I just started with this little "formula", I don't know how normal/unusual this is.
It sounds extremely strange. I would've guessed that 0.01 ₿ or something would be the most common amount. Not multiple Bitcoins at once. Certainly not 6.10 ₿ on average.
Is this an extreme 24 hours in that sense? Or is this normal?! Or has there been some really MASSIVE single one which skews the average for today grossly?


texts:
I'm looking for a command line address calculator, where I can put in my private exponent and get out a bitcoin address in Base-58 encode. Does anyone know some free software that will allow me to do this? Basically like http://brainwallet.org/ but off line.

Thanks.


texts:
I am using LND (most recent version 0.6.1-beta) and I have a lot of pending channels in state
pending_open_channels
which are stuck for many days (perhaps because of low fee and  full mempool) so I want to reset those transactions from my LND/bitcoind or just increase a fee so that could be mined and the channel open.

What options do I have? Can I just delete/reset all pending channels somehow? Or wait or what.

Many thanks for your attention and ideas.


texts:
Suppose that someone seized my seed with a phrase of 12 words. I deliberately changed the order of words in a phrase in such a way that the only way to get a real phrase is to go through all the possible combinacies of the current 12 words.

1) How many combinations will it be necessary to go through an attacker in order to find a real seed? How long can it take?

2) Do you find such precaution really effective?


texts:
Is it possible to enable a 2 of 3 transaction without the escrow component defined as "nobody can run off with the funds but the funds have to exist"

In a scenario where A wants to pay C and requires intermediary B for multisig.

Is it possible for A to authorize a transaction with B and C with one partially signed signature, and then B and C can combine that signature to create a transaction? B and C will have several ways to determine if funds are available from A, but for sake of brevity lets assume A has funds


texts: Windows 7 : Unable to start bitcoin server using daemon in regtest : bitcoind -regtest -daemon

texts:
I am trying to start bitcoin server in regtest mode using bitcoind -regtest -daemon command on my windows 7 operating system. Error I am getting is
daemon is not supported on this operating system.

My bitcoin configuration is:

regtest=1
rpcuser=username
rpcpassword=password
rpctimeout=30
rpcallowip=192.168.1.1/24
rpcport=8332
rpcconnect=127.0.0.1
rpcssl=1
# OpenSSL settings used when rpcssl=1
rpcsslciphers=TLSv1+HIGH:!SSLv2:!aNULL:!eNULL:!AH:!3DES:@STRENGTH
rpcsslcertificatechainfile=server.cert
rpcsslprivatekeyfile=server.pem

gen=1
keypool=100
paytxfee=0.00001000

I am a novice so please bear with me if this is a basic question. Tried multiple times but getting same daemon not supported error.


texts: How exactly does the network know if the miner has put forth a valid proof of work?

texts:
If all that the miner needs to do is find a hash with a certain number of leading 0's of the block's header, couldn't they just find a random hash with the required number of 0's that isn't necessarily the hash of the block header? How would the nodes know?

How exactly do the nodes decide if the proof of work is valid? What protocol is used for this?


texts: So the question is can i start mining(solo)/using my wallet for transactions or whatever when my wallet is not sync'd? I've tried to mine solo but it doesn't work =(.


texts: Is there a uniform measure of "difficulty", that when multiplied by price, will give "profitability of one hour of mining"?

texts:
I recently open Bitcoin Pie, a site that compares crypto-currencies.

Given the exchange rate in BTC, I would like to add another column that tells "relative mining profitability", regardless of the hardware used.

So, if at a given moment, BTC mines at difficulty X, NMC at Y, and FooCoin at Z, with the conversion rates to BTC being 1, N_BTC, and F_BTC respectively, just comparing X, Y*N_BTC, and Z*F_BTC should give an indication of which one a rational miner should mine.

What is a good number to use in the difficulty column? Where are the APIs for it? Is it just plain "difficulty", or is it some other number?

I'm not sure how to take merged Namecoin mining into account here. Any ideas?

CPU and GPU coins should not be measured on the same scale.


texts: What would you call bitcoin wallet that give access to private keys unlike coinbase.com for example?

texts:
Any Suggestions?

I suggest Non-custodial Bitcoin Wallet, But i feel it's not appropriate.


texts: Bitcoins mysteriously transferred out of my wallet?

texts:
I started mining bitcoins a few months ago, picked up a couple ASIC miners and have had my computer using them. I've been mining using Slush pool. I had my settings set to send bitcoins to my address when I reached 0.1 bitcoins.

I finally reached that yesterday, and Slush sent me my 0.1 (actually, it sent 0.1000341, because I was slightly above). The transaction can be seen as the second transaction on this page: https://blockchain.info/address/1LxLWPmzh3uMCmTwterHoFkrQagsFoF3Wm

Now, that was great, I now have 0.1 bitcoins! Then, when I got home from work today, I checked my bitcoin wallet and I noticed that it said I have 0 bitcoins! I checked the transactions, and there's a second one listed. The second one listed is for the exact amount I just received, with a transaction date/time of "28 Feb 2014 01:49", just under 8 hours after I received the bitcoins. (transaction listed at the top of the link posted above)

Does anyone know what happened? Did someone break into my wallet? Wouldn't they need my private key and my password to do that? Is there something else going on that I don't know about?


texts: How does BIP 0070 work for me, the user?

texts:
BIP 0070 (the payment protocol) is included in Bitcoin-core 0.9.0. The main idea behind it is to simplify the sending of bitcoins to a service by making it a more p2p thing.

My question is this, from the user's perspective, how would this work? Does a website give me a link or button to click and then I authorize a payment?


texts: I'm digging further into the open Taproot PR. Can you explain the bip340_test_vectors?

texts:
I'm digging further into the open Taproot PR. I found these bip340_test_vectors.
They have secret keys, public keys, aux_rand (auxiliary randomness), message, signature and whether the signature verifies or not. Can you explain why the signatures that fail are failing?


texts:
I have Successfully integrated Bitcoin To get payment so to verify Transaction from given address, I use
https://blockchain.info/multiaddr?active=$address|$address
, which is working for Bitcoin.

So now I want to integrate Bitcoin Cash. For Bitcoin cash what is the base URL from blockchain.info.

I search for this many places. I am not able to find a solution.

Plz suggest me to integrate for test net for bitcoin cash too.


texts: When creating a block, who actually generates the 25 bitcoins that act as a reward?

texts:
I realise that somebody who manages to find a new block in the blockchain gets 25 bitcoins as a "reward".

Where do these bitcoins actually come from? How are they minted? How are they actually generated? What's the "everyman's" explanation of what happens, in the blockchain, so that these "new" 25 bitcoins are actually created?