texts:
Since I own two FPGA:s I want to get started mining. It doesn't matter which currency I am mining, only that it works. I would prefer to do mining of Bitcoin, Ether, Dash or LItecoin but anything that works with my FPGA will do.

My FPGAs are Altera DE2 and Altera DE2-115. I already checked out one project that was too old (it used the getwork call which has been deprecated.

Any suggestions what I should do? I know C programming and some electronics and VHDL so I can find my way around a complicated installation or building it.


texts: How to increase the speed of synchronisation?

texts: What ways are there to increase the speed of synchronisation of the network, assuming the use of the main Bitcoin client?


texts:
I need to extract last wallet transaction. But seems  listtransaction has some wrong logic. When I perform this function
listtransactions '*' 50 9

it just return me first records not last. In my case I have 11 records, so it return me record 1 and 2, instead of 10 and 11 as I expected. Thus I get first two records instead of last. Maybe I understood something wrong or missed some other params?


texts: Can you use lower dual fuel electricity rates to run a crypto miner for heating with a second back up heat source?

texts: Dual fuel electricity rates are significantly lower than standard rates.  There are devices made in Russia that are specifically sold as Bitcoin mining space heaters.  Is it permitted to use a crypto currency miner for heating and thus qualify for the lower energy rates?


texts:
I set up my bitcoind to run on tor network.
When I list peers, I get 8 outbound connections and 4 inbound, which all have

"addr": "127.0.0.1:46310",
"addrlocal": "****.onion:8333",

where the addrlocal addres is mine listening address.

Why are there inbound connections to myself?


texts: What python code is necessary to convert the integers of a bitcoin public key into the proper hex version thereof?

texts:
If I get a public key of two integers, x and y values what code is necessary to convert them into their hex versions without any additional letters, or numbers?  This is half a Python programming question and half a bitcoin question though I think it is better asked here due to the familiarity with bitcoin requirements.
Pseudo code:

xpublickey = 20091690549896866803343277351761137627937393619088856147056855893222768847187
ypublickey = 69823032225116710867248379519530157435196049639426167980995931003755153241086
hexpublickey = "04" + hex(xpublickey) + hex(ypublickey)

I don't know what code is necessary to turn it into (as the above code does not work):

042C6B7E6DA7633C8F226891CC7FA8E5EC84F8EACC792A46786EFC869A408D29539A5E6F8DE3F71C0014E8EA71691C7B41F45C083A074FEF7AB5C321753BA2B3FE


texts: Why so many warnings about importing private keys?

texts: Blockchain.info and other products make you read dire (but vague) warnings that "you must be an expert" before you can import private keys.  What's that all about?


texts: I keep hearing about MAST, what is it and what does it do?

texts:
So, somebody asked me about MAST yesterday.

Apparently, it's formalized in BIP114 – Merkelized Abstract Syntax Trees.

I couldn't explain what it was and what advantages it'll bring us.

What are MAST, and how will they help with scaling?


texts:
How do I determine if the current transaction is an outgoing or an incoming transaction from looking at the following API response?

https://blockstream.info/api/address/1A6HUTtraLwTg48AwpQxPwLmTnDGSSJteG/txs


texts:
What are the tangible benefits of decentralisation?

This question was posed to me by my parents. Under that this question might incur a lot of wrath from this community.

When my parents lose their ATM cards, they can go to the bank to queue up to get their ATM card if they provide their identification card.

Unlike the above scenario, when one loses his/her private key, one loses access all his BTC.

Hence this question -- Other than removing intermediaries, what are the tangible/immediate benefits of decentralisation? Frictionless commerce, etc.

Nathan Aw


texts: how to compile brainflayar in window based Linux

texts:
hi can any one explain how they do it like this 1EpisodeiV111111111111111111wbq9i2 1ANewHope1111111111111111111vnYm6D 1itisAPeriodofCiviLWarRebeLyzK2rV 1SpaceshipsStrikingFromA111vh24Fi 1HiddenBaseHaveWonTheirFirstVCugGV 1VictoryAgainstTheEviL111123YSBKF 1GaLacticEmpire1111111111111xsW5HG 1DuringTheBattLeRebeLSpies11ybfhTP 1ManagedToSteaLSecretPLansToxvKf4K 1TheEmpiresULtimateWeapon11zoRcyn 1TheDEATHSTARAnArmoredSpacezUyCHa 1StationWithEnoughPowerTo11vFTWwP 1DestroyAnEntirePLanet1111122KUcy5 111111111111111111112xT3273 111111111111111111114ysyUW1 1111111111111111111141MmnWZ 1111111111111111111114oLvT2 1PursuedByTheEmpiresSinisterypjWrk 1AgentsPrincessLeiaRacesHomewxuNTT 1AboardHerStarshipCustodian1yhX6zg 1ofTheStoLenPLansThatCan111zCJt3F 1SaveHerPeopLeAndRestore111yULD1y 1FreedomToTheGaLaxy1111111122roNk3

last 6 char dont care

but how it is possible can any one help me to gen address in specific private key from to option

i try to use brainflayar , bitcoin-rnn , blockparser but unable to compile i run Linux Ubuntu command line in windows pls help


texts: Is there a risk of double-spending when making a face-to-face transaction?

texts: When exchanging funds or services face-to-face, is there a risk of a double-spending attack? If there is, how could it be technically done?


texts: How to download bitcoin blockchain without core?

texts: I tried to download the entire blockchain using bitcoin-core but i took about 9 days and eventually gone corrupted and i had to delete and restart. Any source to download through torrent or regular browser download?


texts: Python source code for issuing a new altcoin?

texts:
I was wondering if anyone here know a python source code for making an altcoin? I found some tutorial on C++, but since I am not familiar with the language I cannot understand the code fully?
And if there are not any python code for that, what is the reason?


texts: RPC Command to send from multiple accounts to one account (default - "") in same wallet

texts:
I have small amounts in multiple accounts in the same wallet. I want to send all of them to default account (usually named as ""). Is their any RPC command available for this scenario?

Thanks in advance


texts: Please help me understand primecoin mining performance

texts:
I've just started mining primecoin over my hp proliant dl380 g5 server with e5420.

So I'm using ypool.net as the pool and using their latest software: jhPrimeminer_RdBBeta4.0F2_x64.zip

When I check the site stats I see i get a value of 0.0514 share/h. Is this all good or am I having poor performance?

As I'm new to primecoin, having difficulties to understand it.


texts:
I have a problem.
IS this a massive scam?
I invested £3,000 all in all with digital-miners.com the trader kept telling me that I could w/d my money anytime with no problem. Today I was told by my trader that I was no longer going to be trading with them as ''there were too many investors'' and a blockchain broker or someone like that would ring me, when I kept asking my trader about transferring money, he just kept saying the other person would ring me and kept avoiding the question.
When the other person rang me they said I had the money/bitcoin in my account but would need to send 10% £3,700 in advance to get the £37,000 in my account and it was now in a locked wallet. I can still trade with the money as I tried, but he says I can't get the money or bitcoin without paying the fee to liquidate it. I told him I don't need him to liquidate it, he can just send the Bitcoin to my Exodus account, but he said he can't do that without the fee as it is now in a locked wallet.
Anyone can help with advice on this would be appreciated. It was not done consensually and I don't understand why a trader would just drop me like that with £37,000 in my account unless it is to try to scam me out of the £3,700 to try to get the £37,000 that will never appear.
UPDATE... The guy who rang me about liquidating my funds has now said Digital-miners.com would allow the money to be refunded back to my account if I took down the post I made on trust pilot.. he said they would ring me about it.. I am still waiting for the call.


texts: In Peercoin style Proof of Stake, can one person 'stake' for another's address?

texts:
The parameters included in the staking are listed here:

// ppcoin kernel protocol
// coinstake must meet hash target according to the protocol:
// kernel (input 0) must meet the formula
//     hash(nStakeModifier + txPrev.block.nTime + txPrev.offset + txPrev.nTime + txPrev.vout.n + nTime) < bnTarget * nCoinDayWeight
// this ensures that the chance of getting a coinstake is proportional to the
// amount of coin age one owns.
// The reason this hash is chosen is the following:
//   nStakeModifier:
//       (v0.3) scrambles computation to make it very difficult to precompute
//              future proof-of-stake at the time of the coin's confirmation
//       (v0.2) nBits (deprecated): encodes all past block timestamps
//   txPrev.block.nTime: prevent nodes from guessing a good timestamp to
//                       generate transaction for future advantage
//   txPrev.offset: offset of txPrev inside block, to reduce the chance of
//                  nodes generating coinstake at the same time
//   txPrev.nTime: reduce the chance of nodes generating coinstake at the same
//                 time
//   txPrev.vout.n: output number of txPrev, to reduce the chance of nodes
//                  generating coinstake at the same time
//   block/tx hash should not be used here as they can be generated in vast
//   quantities so as to generate blocks faster, degrading the system back into
//   a proof-of-work situation.
//

I don't see anything that proves ownership of the coins that were staked in a particular output. I assume there must be something, though, or else anyone could stake with anyone else's UTXOs. What am I missing?

Maybe it is just a requirement that there be a transactions spending the output be included in the block? If so, then if someone created that initial transaction, then they could give it to someone else and let them do the manual labor of checking once per second to see if their stake succeeds?


texts: How to return Tx to mem pool from orphan block

texts:
This question is centered around the implementation of how transactions on an orphan block return to the mem pool.

In my understanding, once a block becomes orphan all it's transactions (that aren't on other non-orphan blocks) need to return to the mem pool.

Do we start from genesis block until we reach the last block of the active chain checking every transaction along the way, or is it there a more efficient algorithm that's based on some constraint/property that allows the algorithm to start from a more recent block?

Proto code for starting from the genesis block:

Blockchain blockchain = ...
function Dictionary<Key, Tx> deleteOrphanTx (Dictionary<Key, Tx> orphanTx) {
    foreach (Block currBlock : blockchain.getBlocks())
        foreach (Tx tx : currBlock.getTx())
            Key txKey = tx.getKey();
            if(orphanTx.contains(txKey)
                orphanTx.remove(txKey);
    return orphanTx;
}


texts: When exactly do the transactions get validated?

texts:
I have some gaps in my understanding to the life cycle of the transaction that I want someone to help me fill them specially with the validation.

What I understand about the life cycle with my questions:

1) Transaction is signed off by the user through the wallet app and broadcasted to the blockchain network.

The question at this step is: does the wallet app perform any kind of transaction validation that requires to check the whole history of the blockchain at this level ?

2) The broadcasted transaction is now sent to many nodes on the network, and these nodes forward/ "propagate" the transactions to other nodes till all the nodes have this transaction in their "pool of unconfirmed transactions" ?

Tell me if I'm getting any part wrong or not in it's right order

3) Each miner will pick some transactions and start the mining (doing the proof of work till finding a correct hash)

At this level when the miner picks the transactions, does he perform a validation of each transaction that requires full scan of the history of the blockchain ?

4) When the miner solves the block, he will broadcast that block along with the hashed value he produced to the blockchain network in the same way the transaction was broadcasted to some nodes and propagated to the rest. Then the nodes will hash the block header to verify whether or not it produces the same hash so they can accept that block.

The question here is: do the nodes perform another validation at all the transactions sent with the block header to verify they are real transactions not fake ones created by the miner who solved the block ?

Does the validations on these transactions require a check against all the history of the blockchain ?

I know how merkle trees hash multiple transactions and that any modification to a transaction's hash will change the merkle root's value, but my question here is how is that helpful ? wouldn't the miner who already faked up any of the transactions have the right merkle root for all the transactions in the block since he is the one who added them in the first place ? My point is how does merkle root help ? what value does it add ? what kind of attack does it prevent ?

The last question is the consensus, from its definition it is that all nodes agree that they are at the same level with the new block. I know the PoW, but how all the nodes check and communicate together to acknowledge that all of them got the same block ?


texts: How to generate the hash of public key in Bitcoin

texts:
I'm trying to hash the public key with SHA256 and then ripemed160 and get the hash. but it gives the wrong hash

Public key:  2b4632d08485ff1df2db55b9dafd23347d1c47a457072a1e87be26896549a8737

Hash should be: 93ce48570b55c42c2af816aeaba06cfee1224fae

Imports System.Security.Cryptography
Imports System.Text
Imports System.Globalization
Imports System.Numerics

Private Function HexStringToByteArray(ByVal shex As String) As Byte()
    Dim B As Byte() = Enumerable.Range(0, shex.Length).Where(Function(x) x Mod 2 = 0).[Select](Function(x) Convert.ToByte(shex.Substring(x, 2), 16)).ToArray()
    Return Enumerable.Range(0, shex.Length).Where(Function(x) x Mod 2 = 0).[Select](Function(x) Convert.ToByte(shex.Substring(x, 2), 16)).ToArray()
End Function

Private Sub Button12_Click(sender As Object, e As EventArgs) Handles Button12.Click

Dim public_key as String = "2b4632d08485ff1df2db55b9dafd23347d1c47a457072a1e87be26896549a8737"
   Dim pubkey_hash As String

    Dim sha256 As SHA256 = SHA256Managed.Create()
    Dim bytes As Byte() = System.Text.Encoding.Unicode.GetBytes(public_key)
    Dim hash As Byte() = sha256.ComputeHash(bytes)
    Dim stringBuilder1 As New StringBuilder()

    For i As Integer = 0 To hash.Length - 1
        stringBuilder1.Append(hash(i).ToString("X2"))
    Next

    bytes = HexStringToByteArray(stringBuilder1.ToString())

    Dim ripemd160 As RIPEMD160 = RIPEMD160Managed.Create()
    Dim hash_160 As Byte() = ripemd160.ComputeHash(bytes)

    Dim stringBuilder2 As New StringBuilder()

    For i As Integer = 0 To hash_160.Length - 1
        stringBuilder2.Append(hash_160(i).ToString("X2"))
    Next

    Dim arr() As Char = stringBuilder2.ToString

    pubkey_hash = arr.tostring
    TextBox14.Text = pubkey_hash

   End Sub

and is there any way I can shorten this code? loops & if statements etc


texts:
I have some doubts about naming in witness script/transaction.

P2SH-P2WSH (multisig)

WITNESS_SCRIPT = OP_3 <public key1> <public key2> <public key3> <OP_2>

(is it witness script or redeem script? For now I will call Witness script)

SCRIPTHASH= SHA256 (WITNESS_SCRIPT)

is it Witness script Hash or redeem script Hash?

REDEEM_SCRIPT=0020+SCRIPTHASH

is it redeem script? Maybe it's the redeem script because it is in Scriptsig. (Witness version + Witness program)

In scriptPubKey
hash160 of (0020+SCRIPTHASH).

What is its name? Hash160 of ?

And We have OP_HASH160 <Redeem script hash?> OP_EQUAL

P2SH-P2WPKH

KEYHASH = hash160(<public key>)

REDEEM_SCRIPT=0014+KEYHASH

is it redeem script or witness script? For now I Will call redeem script.

In scriptPubKey
hash160 of (0020+SCRIPTHASH).

What is its name? Hash160 of ?

And We have OP_HASH160 <Redeem script hash?> OP_EQUAL

P2WPKH NATIVE

WITNESS SCRIPT = hash160(<public key>)

In scriptpubkey
0014+WITNESS_SCRIPT

OP_0 <20 bytes witness script hash>

P2WSH NATIVE

WITNESS SCRIPT = <OP_2> <pubkey1><pubkey2><pubkey3><OP_3> <OP_CHECKMULTISIG>

WITNESS_SCRIPT_HASH = HASH160 (WITNESS SCRIPT)

In scriptpubkey

0020+WITNESS_SCRIPT_HASH

OP_0 <32 bytes witness script hash>

P2WPKH NATIVE and P2WSH NATIVE should be ok


texts:
Background how I got here:
I have a very old wallet file in .dat format (from 2017)
The backup is as far as I remember just a copy of the wallet file from bitcoin-core's ~/.bitcoin directory.
I tried opening it in "modern" bitcoin-core by:

copying the wallet file into ~/.bitcoin/wallets/walletName/walletName.dat
adding the wallet name to list in ~/.bitcoin/settings.json

Now, upon starting bitcoin-core I get this message:
Error: Failed to load database path '/home/{redacted}/.bitcoin/wallets/OldWallet_1'. Data is not in recognized format.

So, having no meaningful results in google other than pywallet, I decided to try importing it to electron... and discovered that electron doesn't have an option to import bitcoin-core wallets (wtf?).
I did find some information about "pywallet", I tried using it to recover information from my .dat file, I had to modify it a bit since my encryption password is really long and has many weird characters in it so passing it as an argument for script execution is incredibly difficult.
I managed to get list of all addresses defined in this file and "encrypted_privkey" for each address.
I didn't manage to get it to decrypt anything, because the script crashes with "Segmentation Fault (core dumped)" (everyone loves C/C++).
The question:
So, my question is, given I know the password to this wallet (I think I also recovered the encryption salt) and I have "encrypted_privkey" list, how do I decrypt them so I can import them in electron?
[edit]
I just tried importing my dashcoin wallet to dash-core, I get the same error message, so it's very likely that something about the wallet file format has changed during the time I wasn't using cryptocurrencies.
If anyone knows how to "upgrade" the file format, please let me know, it'll also solve the problem.


texts: Is there an Android Bitcoin app that can interact with other Android Apps on the same device?

texts:
Suppose I'm developing a Bitcoin-based Android app.  It could do anything: user pays Bitcoins to play a game, order a pizza, accept charitable donations.  Whatever it does, it does it in Bitcoins, and it's targeted to people who are Bitcoin savvy and probably already have the ability to access Bitcoins on their Android device.  I don't want to deal with the user's wallet, nor do I want the user to have to trust their wallet to my app.

I can think of two ways to do this:

1) there already is a Bitcoin wallet app that runs an  Android Provider that my app can access.  When I need to send Bitcoins from the wallet, my app communicates with the Provider, and the other app gets the user's approval and protects their wallet from my app stealing their Bitcoins.
2) There is a Bitcoin wallet app that I can send an Android Intent to, and as in #1 that other app confirms the user's approval before any Bitcoins leave the wallet.

So I have two questions:

Am I missing another way to do this?  To make an app that can send the user's Bitcoins without me touching the wallet directly but using some other app they already trust?  (And without cutting and pasting a Bitcoin address.)
Assuming this is the way to do it, are there any such Android apps?

A search of Google Play for "Bitcoin" turns up many results, but from a small sample the only ones I've seen that actually transfer Bitcoins seem to work off QR codes or NFC.  They will interact with other Android devices, but I don't see one that interacts with other Android apps on the same device.  But then again, I doubt the description for end users would have information like that.


texts: Are there any laws that govern the use of crypto currencies in the international law?

texts: I want to start up a Bitcoin exchange in Kampala Uganda but I want to first know what the law says on crypto currencies.


texts: "Fork choice rule" : A general term? or a specific algorithm?

texts:
Is "Fork choice rule" a general term including all the algorithms used for choosing a branch among other branches in a fork (including longest chain rule in Bitcoin etc) ?
Or is it a specific algorithm designed for Casper Ethereum ?


texts: How does the Bitcoin Standard Client wallet encryption work?

texts:
I encrypted my wallet using Bitcoin QT, then closed the application. When I restarted Bitcoin QT, it did not ask for the passphrase. But I could still access the wallet.

How is it possible to access an encrypted wallet without the passphrase?

Does it save the passphrase somewhere?

What is the purpose of encrypting a wallet and not requiring the passphrase?

If you re-install Bitcoin QT do you need to enter the passphrase?

What if you transfer the wallet.dat file to another computer? Would you need the passphrase to access it?

Do you need the passphrase to access a backup of the wallet file?

Do you need the passphrase to access a copy of the wallet file?

I searched and did not find basic information about using Bitcoin QT. Is there documentation somewhere?


texts: Recipient calculation in verifyTransactionBytes for Ardor

texts:
I'm trying to add verifyTransactionBytes to my app.  I am currently stuck because of transaction.recipient !== data.recipient.  I don't understand how transaction.recipient will ever equal data.recipient.

data.recipient equals ARDOR-64L4-C4H9-Z9PU-9YKDT

However,  transaction.recipient equals 12686039152117651770352583052021228896653772998482022211948610002430512793010043372255281183988421160450227631016638876582933743874739812608892576232835541561180017189881475915550182092483428449468438018195304514943626747005224233901130236596723251118266281272406204049816147466250586545776300564249483796886483621200942491492199171631589798205980673

This doesn't really surprise me, because I don't see how an ARDOR address gets generated from transaction.recipient = String(helpers.byteArrayToBigInteger(byteArray, pos));

Which looks like it should return a number, not a string.  What am I missing


texts: Is it possible to specify a default change address?

texts:
Is it possible to enable default change address on my bitcoin-qt (aka bitcoin-core) client?

I'm using a webservice that monitors my balance (based on public keys) and whenever I send a transaction my balance goes to 0.0000 because my whole funds end up in a random change address.

I know there is a coincontrol option to specify a change address, but sometimes I forget to enter an address. Is there any way to configure the client to use a default change address? Where all changes end up?


texts: How is a Transaction protected from tampering before inclusion in a Block?

texts:
Using the terminology from: https://en.bitcoin.it/wiki/Protocol_specification#tx

What prevents an attacker operating a rogue client from replacing the tx_out[] of a transaction with values that assign the output of the transaction to the attacker?

The tx_in[] is unchanged (and presumably valid), but the outputs now benefit the attacker.

A new hash can then be calculated and announced by the rogue client using the inv message.

If nothing prevents this occurring, how does the Bitcoin network prevent this rogue transaction from being included in a block?

[Not having anyway to comment at this point]

Thanks David, that clarified greatly my [mis]understanding of the documentation at:

https://en.bitcoin.it/wiki/Script#Crypto

The OP_CHECKSIG description says in part:

  The entire transaction's outputs, inputs, and script (from the most
  recently-executed OP_CODESEPARATOR to the end) are hashed.

I'd thought "the entire transaction" was the preceding transaction, not the redeeming transaction, that was signed as you describe.

Thank you again for helping me out.


texts: Is a private key used up when part of the bitcoins it controls are sent?

texts:
Here is my current understanding of Bitcoin:

I have 10 bitcoins in my wallet.

If I send 5 bitcoins to someone else, I am sending the private key from my wallet to somebody's public key address.

Those are combined into a new transaction that is later confirmed by miners. The miners confirm that I owned the bitcoins by checking my private key, and that the receiver's public key is valid.

Then, the miners create a new private key that is sent to the receiver's wallet.

On a simple True/False basis, is everything I have said right so far?

If so, what happens to the remaining 5 bitcoins in my wallet?  Do they magically get a new private key, or what? How does my wallet know how many I have left, and how do the remaining bitcoins get a new identity?


texts: How do I remove hard coded seeds from the bitcoin source code?

texts:
I'm experimenting with blockchains at home and in my debug logs are lots of errors showing that my nodes are trying to get addresses from the hard coded seed nodes, I know I can use connect to turn off this behaviour but I don't want to have to include that in my bitcoin.conf file.
I am using Bitcoin v0.10.

Any hints greatly appreciated :)


texts: Is an exchange a good substitute for a mixing service?

texts: Isn't an exchange such as MtGox essentially a mixing service? I might be wrong, but can somebody trace coins when they are paid to one address, possibly exchanged, and another amount is paid back from another exchange address back to you? As long as you don't pay back the coins to the same address, and amount is not exactly the same, can this even be traced through blockchain?


texts: Why don't Bitcoin Full Nodes who are not Miners get compensated?

texts: Why don't full nodes who are not miners get compensated for running, storing and validating the network?


texts: If I abandon a slow to verify transaction is my wallet recredited?

texts:
Just tried to transfer some bitcoins to my new trading account online to get some cash out. But as luck would have it the transactions were all massively backlogged and I apparently did not use enough fee to get enough miner's attention to push it out. Was stuck in the limbo of non-verified so tried to see if I could cancel or bump the fees. Since it was not yet verified I did restarted my bitcoin Core with the wallet option to wipe unconfirmed transactions so I could get the client to ungray the "abandon" button. That worked. But now I am unsure if the bitcoin was recredited to my wallet since I forgot to write down the pre/post balances.

When this transaction falls out of mempool (I presume it will) does the wallet get recredited or did that happen automatically when I abandoned the transaction? Just want to make sure I have not just lost some bitcoins in limbo forever...


texts: How can a government ban trading in bitcoin since the people can trade in overseas exchange?

texts:
Recently, bitcoin fell because South Korean government threatened to ban trading. What I fail to understand is how can cryptocurrency trading be banned? Citizens can always trade anonymously in overseas exchange. What can governments do about it if they cannot track the anonymous trading that takes place?

https://www.reuters.com/article/us-southkorea-bitcoin/uproar-over-crackdown-on-cryptocurrencies-divides-south-korea-idUSKBN1F10YG?


texts:
I forked the openwallet-android so that I could add my coin - (placeholders) placeh.io.

The openwallet-android connects to electrumx server. I am able to get my chain to load correctly in electrumx server. The openwallet correctly reads the balance from the address / inputs and you can see your balance through the wallet.

However, when I try to broadcast a transaction I am getting the message:

"mandatory-script-verify-flag-failed (signature must be zero for failed check(multi)sig operation)"

From placehd/placeh network.

Here is some additional information, this is the rawtransaction that is being published. If I try to send the raw transaction in the placeh-cli client, it will not succeed and produces the same error when done manually

Raw Transaction:

placeh-cli decoderawtransaction

01000000017477f59250a8d8a7d94ba5dcc196222c0b6c92849cad210735b4380b24c03b13010000006a473044022053b17723e8a90846fc341006f5f63d5776df619f33cec82d8065e836508672c6022036298087c2f37c3002c4897b74e7de6af8c608c89cbcef07ada9c5551c85f2810121031dc78b8c254649e204b81641f70497980ca6b5574f837001c962930580d1372dffffffff02c00e1602000000001976a914a117ed0f4e2afe1e1b8d2b0253408a7830f2b55688ac0093e651020000001976a914c472af380586ed1638686731cc1eda3c60363ec788ac00000000
{
  "txid": "de045f2220d0b9f34060336c9ed3badc7c22741fec3aa1d87ff24264c3c1fb5e",
  "hash": "de045f2220d0b9f34060336c9ed3badc7c22741fec3aa1d87ff24264c3c1fb5e",
  "version": 1,
  "size": 225,
  "vsize": 225,
  "locktime": 0,
  "vin": [
    {
      "txid": "133bc0240b38b4350721ad9c84926c0b2c2296c1dca54bd9a7d8a85092f57774",
      "vout": 1,
      "scriptSig": {
        "asm": "3044022053b17723e8a90846fc341006f5f63d5776df619f33cec82d8065e836508672c6022036298087c2f37c3002c4897b74e7de6af8c608c89cbcef07ada9c5551c85f281[ALL] 031dc78b8c254649e204b81641f70497980ca6b5574f837001c962930580d1372d",
        "hex": "473044022053b17723e8a90846fc341006f5f63d5776df619f33cec82d8065e836508672c6022036298087c2f37c3002c4897b74e7de6af8c608c89cbcef07ada9c5551c85f2810121031dc78b8c254649e204b81641f70497980ca6b5574f837001c962930580d1372d"
      },
      "sequence": 4294967295
    }
  ],
  "vout": [
    {
      "value": 0.35000000,
      "n": 0,
      "scriptPubKey": {
        "asm": "OP_DUP OP_HASH160 a117ed0f4e2afe1e1b8d2b0253408a7830f2b556 OP_EQUALVERIFY OP_CHECKSIG",
        "hex": "76a914a117ed0f4e2afe1e1b8d2b0253408a7830f2b55688ac",
        "reqSigs": 1,
        "type": "pubkeyhash",
        "addresses": [
          "FLWtv6SuocTFMozTZvdZAhroJLehVjLKhs"
        ]
      }
    },
    {
      "value": 99.64000000,
      "n": 1,
      "scriptPubKey": {
        "asm": "OP_DUP OP_HASH160 c472af380586ed1638686731cc1eda3c60363ec7 OP_EQUALVERIFY OP_CHECKSIG",
        "hex": "76a914c472af380586ed1638686731cc1eda3c60363ec788ac",
        "reqSigs": 1,
        "type": "pubkeyhash",
        "addresses": [
          "FPjqHpEzdYAbxVG2acxz8GWGAPmJsWj6oP"
        ]
      }
    }
  ]
}

I believe this may have something to do with the way that the openwallet is constructing the raw transaction. I would like to update the libraries so that it will be able to broadcast the transaction correctly.


texts: Is there a way to squeeze more hashing rate from a weak hardware?

texts:
I have a computer has two graphic cards ATI Radeon HD 5450, which are almost not used at all.

The computer is running permanently and is used only for office work and data storage.

I tried to setup the minig there and I was i bit disappointed by the hashing power.

GuiMiner was hasning at 2 x 10Mh/s, CGMiner is a bit better, it does 2 x 14Mh/s.

Are those graphic cards so weak that it is not possible to squeeze a bit more out of that?
I can get a third of this hashing rate on the CPU of my 5 years old notebook.

I use just the default settings and I mine by executing cgminer -o host:port -u user -p password -l 1 -T


texts: Which wallets can send to native segregated witness output addresses today?

texts: Which wallets today are able to send to P2WPKH addresses starting with bc1qf…?


texts: sendrawtransaction without downloading blockchain

texts:
Is it possible to use sendrawtransaction without downloading the blockchain? Or will bitcoind reject the broadcast since it can't validate the inputs?

If the client does block it by default, is there any way to force it to send it?


texts: Are Tor .onion-addresses IP address independent?

texts: Is it possible to move the node to a different IP address and keep the existing (=preciously open and funded) channels functional?


texts:
I am using multibit and I need to buy some bitcoin (real money needed) and sell bitcoin(real money needed too)

But I cannot find any article on google that guide you how to make the money payment in transaction.

how can I pay or recieve money when I try to buy or sell bitcoin？

thank you so much


texts: Since Bitcoin has no central system, where do network request go?

texts:
I heard bitcoin and other cryptocurrencies have no central system.
BUT where do you send the transaction id?
There must be a server to send the data to!?
It probably is a simple question but, that's the thing I never understood on bitcoin and cryptocurrency.


texts: bitcoin address to Hash 160 public key : not consistantly reversible?

texts:
When I use blockchain.info tools or bitcointoolkit.info tools

to convert an address, such as 1MCNpVGDY7BGjJyWZL5FJZiaVkQEiuxy8H
to a hash 160 public key : I get dd894dfc0f473c44cc983b5dd462bc1b393f7498

However, if i convert 3MtPk2kf61VepUfwgRjqjC5WeGgxE4rRPS
i get the SAME 160 hash address ie dd894dfc0f473c44cc983b5dd462bc1b393f7498

I am baffled by this. I thought a hash 160 should UNIQUELY convert between it and the Address and back ???

I also found other address that convert back fro hash160 to the wrong address....

thanks for any clarification.....

9a278585c51203bca9f0e5c107814ecef6f2aa12


texts: Is there a counterparty whitepaper? What about a specification?


texts: Sent Bitcoin to my electrum wallet address without hitting request first now it says its confirmed and i have no money after requesting it after Isent it. Can I still receive my coin


texts: How do I backup my wallet with bitcoin-cli over RPC?

texts:
hendry@knuckles ~ $ bitcoin-cli backupwallet /home/hendry/backup.dat
error code: -1
error message:
boost::filesystem::status: Permission denied: "/home/hendry/backup.dat"

Reddit couldn't help me https://www.reddit.com/r/BitcoinBeginners/comments/aftb91/am_i_running_bitcoin_core/

This is no permission problem.

hendry@knuckles ~ $ touch backup.dat
hendry@knuckles ~ $ ls backup.dat
backup.dat
hendry@knuckles ~ $ rm backup.dat

I suspect the bitcoind -server which runs in isolation as "nobody" is trying to access my home directory, which is a bit of a concern. My user's .bitcoin directory looks fine:

hendry@knuckles ~ $ find .bitcoin/
.bitcoin/
.bitcoin/mempool.dat
.bitcoin/wallets
.bitcoin/wallets/wallet.dat
.bitcoin/wallets/db.log
.bitcoin/wallets/.walletlock
.bitcoin/.lock
.bitcoin/chainstate
.bitcoin/chainstate/000003.log
.bitcoin/chainstate/CURRENT
.bitcoin/chainstate/MANIFEST-000002
.bitcoin/chainstate/LOCK
.bitcoin/fee_estimates.dat
.bitcoin/banlist.dat
.bitcoin/blocks
.bitcoin/blocks/index
.bitcoin/blocks/index/000003.log
.bitcoin/blocks/index/CURRENT
.bitcoin/blocks/index/000004.log
.bitcoin/blocks/index/MANIFEST-000002
.bitcoin/blocks/index/LOCK
.bitcoin/blocks/index/000005.ldb
.bitcoin/blocks/rev00000.dat
.bitcoin/blocks/blk00000.dat
.bitcoin/peers.dat
.bitcoin/bitcoin.conf
.bitcoin/debug.log


texts:
I searched already but I couldn't find anything about the structure of a bitcoin.

My understanding is that a bitcoin, which is different AFAIK from a bitcoin address, can be interpreted as a string of numbers and characters (alphanumeric). How long is a bitcoin string (min/max)?

I found here (https://blockexplorer.com/block/000000000000000002109f32aeac7a036232b0116f939326651e739a28e6d6b6) now a size of: 934325 bytes for a particular bitcoin. Could this be the length of the particular bitcoin?

PS: I searched always for length and not for size...


texts: What happened to the bootstrap.dat provided by bitcoin.org?

texts:
I could download a bootstrap.dat.torrent from  bitcoin.org before, but it is no longer available. Does bitcoin.org still maintain it?

Is there another source for downloading a bootstrap.dat? I am stuck with a 0.9.x version of BitcoinCore for testing purposes, and the bootstrap.dat would improve synchronization for me.


texts: I am a motivated first timer in Hawaii! Looking for friend/mentor

texts: I've set up a Blockchain account, because I've spent a couple days on all the Davi sets, researching and gaining all these satoshi, but my account balance is still current at zero. After all that work I thought I'd see something. I started microwallets, and been doing all things new. I could really appreciate someone to help walk me through some steps. I'll keep researching and I'm a voracious student. Many thanks


texts: Bitcoin: error parsing json in bashscript to send BTC using sendmany command

texts:
I am simulating a bitcoin network on my machine for which I have written a bash script to simulate the transactions between the nodes. When I use the sendmany option of bitcoin-cli to send transactions I am getting an json parsing error reported by bitcoin-cli.

Code:

#!/bin/bash
MAX_NODES=2
MY_PATH=/home/ubuntu/test
CLIENT=/usr/local/bin/bitcoin-cli

declare -a addr

function fcomp() {
        /usr/bin/awk -v n1=$1 -v n2=$2 'BEGIN{ if (n1>n2) exit 0; exit 1}'
}

json="'{"

#get addresses to send
for ((i = 1; i <= MAX_NODES; i++));
do
    addr[$i-1]="$($CLIENT -regtest -rpcport=$((16500 + $i)) -datadir=$MY_PATH/$i/ getnewaddress myaccount)"
    if [ "$i" -lt "$MAX_NODES" ]
    then
        json="$json\"${addr[$i-1]}\":0.00001, "
    else
        json="$json\"${addr[$i-1]}\":0.00001"
    fi
done

json="$json}'"
echo $json

#loop to send money to other nodes
for ((i = 1; i <= MAX_NODES; i++));
do
        balance=`$CLIENT -regtest -rpcport=$((16500 + $i)) -datadir=$MY_PATH/$i/ getbalance`
        if fcomp $balance 0.002; then
                $CLIENT -regtest -rpcport=$((16500 + $i)) -datadir=$MY_PATH/$i sendmany myaccount $json
    fi
done

echo json output:

'{"mj2FrDhEomSzyQtRoGY78oVRPcQs5L5o95":0.00001, "mkxnkT3kx9dsFS8V3qYydpL1o5F5MfwCvM":0.00001}'

This gives me an error as:

error: Error parsing JSON:'{"mj2FrDhEomSzyQtRoGY78oVRPcQs5L5o95":0.00001,

I tried all possible combinations of quotes, double quotes and escape sequences but failed. If I copy paste the output of echo $json to a manual bitcoin-cli sendmany command it works perfectly fine.


texts: How to install bitcoind (Bitcoin Core) on Ubuntu?

texts: I want to install a command line-only full node bitcoind on a mini PC with 4GB RAM and Ubuntu. What are the steps to do it and how can I check if it works?


texts: Can you differentiate the miners from the normal clients, by doing some frequency analysis on ip-addresses that announce new blocks? Or will the new block propagate so fast around the network by normal clients that it's impossible.


texts:
I mistakenly sent some bitcoins to a wrong address. The mistake was from the wallet address I was given. An extra letter was added, making the address 35 digits. Is there a way I can reach the owner of the wallet address I mistakenly sent it to? Please help me.

This is the wrong address that bitcoin was sent to
114dW3JX2sPPLVDnX4H8u2vsMc4CEJ3rVYf
It's a blockchain wallet.


texts: Is it possible to exchange Polish Zloty for Bitcoin with CoinFloor Exchange?

texts:
CoinFloor is an exchange that accepts deposits and withdrawals of fiat currencies EUR, GBP, USD and PLN. One can trade EUR, GBP and USD for bitcoin, but not PLN.

In fact it doesn't seem possible to trade PLN for anything, not even other fiats. Of course, it doesn't make much sense for them to accept PLN if you can't do anything with it, so I could be mistaken. If I deposit PLN, is it possible to trade it? How can this be done this?


texts: Can new OP codes be added with a soft fork?

texts:
I understand that P2SH transaction types were added "softly" by repurposing a Tx message that is already valid, so old nodes won't reject them in blocks.

Is there a similar method to adding new script OP codes without a hard fork? In other words, how will old nodes interpret "No Op" commands after they have been repurposed for the upgraded protocol?


texts: I am getting this error when I try to run example_test.py. Is there anything I am doing wrong?


texts: Extracting information from utxo for offline processing

texts:
I would like to extract as much information about the utxo set (all unspent transactions) up to a given block height, including value and scriptpubkey.

This information is meant to be inserted into a database and processed offline for some statistical analysis. I have been looking at multiple alternatives including bitcoind, bitcoin-ruby, libbitcoin and others, but cant figure out how to do this. Perhaps my programming skills arent that hot.

Hoping someone can help me out. Thanks!


texts:
Trying to send HTTP Post request to GDAX with auth. The 'GET' requests work fine and I'm unsure if I am passing the json params correctly as I keep getting Bad Request.

private static JsonObject LimitOrder(String symbol, boolean side, String quantity, String price)
    {
        BigDecimal dPrice = new BigDecimal(price);
        BigDecimal dQuantity = new BigDecimal(quantity);
        String sSide = side?"buy":"sell";
        String param  ="{\"size\":\""+dQuantity.toString()+"\",\"price\":\""+dPrice.toString()+"\",\"side\":\""+sSide+"\",\"product_id\":\""+symbol+"\",\"post_only\":true}";

        try
        {
                String timestamp= Instant.now().getEpochSecond()+"";
                String accessSign = getAccess(timestamp,"POST","/orders");
                String apiKey = properties.getProperty("key");
                String passphrase = properties.getProperty("passphrase");

                URL url = new URL("https://" + properties.getProperty("host") + "/orders");
                HttpURLConnection connection = (HttpURLConnection)url.openConnection();
                connection.setDoOutput(true); // Triggers POST.
                connection.setRequestProperty("Content-Type", "application/json; charset=UTF-8");
                connection.setRequestProperty("CB-ACCESS-KEY", apiKey);
                connection.setRequestProperty("CB-ACCESS-SIGN", accessSign);
                connection.setRequestProperty("CB-ACCESS-PASSPHRASE", passphrase);
                connection.setRequestProperty("CB-ACCESS-TIMESTAMP", timestamp);
                connection.setRequestProperty("accept", "application/json");
                connection.setConnectTimeout(5000);
                connection.setReadTimeout(5000);

        //      System.out.println("WRiting: " + param);
              try (OutputStream output = connection.getOutputStream()) {
                output.write(param.getBytes("UTF-8"));
              }

              String status = connection.getResponseMessage();
                System.out.println("STATUS: "+status);

                BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
                String inputLine;
                StringBuffer content = new StringBuffer();
                while ((inputLine = in.readLine()) != null) {
                    content.append(inputLine);
                }
                if(content.length()>0){
                System.out.println(content);
                }else{
                     System.out.println("Empty Response");

                }
                in.close();

                connection.disconnect();
            }catch(Exception e) {
                e.printStackTrace();
            }
        return null;
    }

and the access sign method below:

 private static String getAccess(String timestamp, String method, String path) throws NoSuchAlgorithmException, InvalidKeyException {
        String secret = properties.getProperty("secret");
        String prehash = timestamp+method+path;

        Mac sha256_HMAC = Mac.getInstance("HmacSHA256");
        byte[] secretDecoded = Base64.getDecoder().decode(secret);
        SecretKeySpec secret_key = new SecretKeySpec(secretDecoded, "HmacSHA256");
        sha256_HMAC.init(secret_key);

        return Base64.getEncoder().encodeToString(sha256_HMAC.doFinal(prehash.getBytes()));
    }


texts: Why does Bitcoin RPC load wallet too slowly?

texts:
I'm trying to load old wallet (which I have not been opening for months) and it takes too much time (~minutes). In this time seems like I can't do any further requests to RPC. After this new calls to this wallet takes milliseconds.
Is it true, that Bitcoin somehow synchronize old wallet with the current state of the network and that's why it takes so much time?


texts: what is the explanation of "witness version" and its usage?

texts:
What is the witness version and how is it used?

A segwit transaction is comprised of:
[nVersion][marker][flag][txins][txouts][witness][nLockTime]

From the BIP: "A witness field starts with a var_int to indicate the number of stack items for the txin."

Where does the witness version come in and in what scenarios can it be used?

Secondly, why does it say witness field starts with a var_int to indicate the number of stack items for the txin -- isn't witness data just signature? Or it simply refers to transactions that have more inputs, and the leading var_init just counts the number of inputs, thus signatures expected?


texts:
Taking the question a step back.

I'm looking to build payment using bitcoin myself. The whole point of bitcoin is decentralisation and sovereignty.

Basically I need High Availability set up for bitcoin full node myself with no single point of failure. So that my website can reliably transact and receive payments.

== Original Text ==
Any one know or tried running bitcoin core server with the data stored on a NAS and a load balancer in front of it?

I'm basically looking for some kind of high availability set up (on aws with autoscaling group / EFS / ELB)


texts: Has anyone experienced money wire from Bitfinex to a european bank? How are the fees applied?

texts: I try to find the best way to cash-out when needed. I use Bitfinex lately and I see that they have a good fee structure (https://www.bitfinex.com/fees - if you know something better let me know). However, I am curious that if it is the same Europe. Is there any one who experienced this and give some information regarding all the fees and disposals I need to consider?


texts: Does sending the "max amount" with given feerate require crafting the transaction twice?

texts:
To make a transaction of "max amount" with a given feerate, is there a shorter procedure than the following?

Craft transaction with with one output
Sign it
Consider the signed length - multiply it with the feerate
Subtract the difference
Set the dest amount
Re-sign it


texts: Why is it recommended to "not send round number amounts when making payments" for increased privacy?

texts:
I got this advice today to increase my Bitcoin privacy:

Do not send round number amounts when making payments (eg send 0.00104103 BTC, instead of 0.001 BTC)

Why do they say this? Why does the amount matter? And either way, it's not like I normally can "decide" how much the amount is, unless shuffling coins around my own wallets?


texts: how can i get blockchain private key using just my wallet address

texts: Please i can get a  private key using the 12 phrases of my wallet using Bip32 but how can i get my wallet private key without the phrases and just having the wallet address


texts: How does bitcoins power consumption compare to other financial institutions/exchanges? (ie banks, stock exchanges)

texts:
So recently in the news there has been some negative reporting bout bitcoins power consumption. "the Bitcoin network is consuming power at an annual rate of 32TWh—about as much as Denmark."  arstechnica

The article makes this look like a bad thing by comparing it to Denmarks power consumption,  But I'm wondering how bitcoins power consumption compares to A) other crypto currencies,  B)  to other financial instuments like The New York Stock Exchange, Nasdaq, or the the US banking system.  I can't seem to find this information by googling.

How does bitcoins power consumption compare to other financial institutions/exchanges?


texts: What's the difference between all kinds of bitcoin addresses (Single, multisig, etc...) also compared to all bitcoin forks?

texts: Bitcoin addresses start with 1. Multisig/Script addresses start with 3. Other forks of bitcoin have single letters that are different at the beginning. Is this letter simply and only prepended to the address after calculating it from the public key, or is there more math to be done in certain cases?


texts: What happens if everyone discovers much faster way of solving hash function problem (mining)?

texts:
The question is not about how bitcoin mining works, but rather how bitcoin system adapts to progress in ability to tackle proof-of-work problems.

Suppose that proof-of-work problems used for bitcoin mining become very easy to solve. (eg. P=NP with very fast practical polynomial-time solver, though of course unlikely, but let me play a hypothetical game.) Then it seems that bitcoin system would collapse - 32-bit nonce may be insufficient to counter how fast proof-of-work can be done, in case that this becomes reality.

Is there any part in the current bitcoin implementation that would protect the bitcoin ecosystem from this type of collapse? Is the "difficulty target" system enough to resolve the hypothetical issue?


texts: Bitcoins sent to address i cannot access, funds are unused Pls Help me get them back

texts: So yesterday i was sending some bitcoin to deposit on my whaleclub.co account like i had done once previous before with no issues, although this time it is saying that my bitcoins were sent to a different address other than mine. As i look at my coinbase transactions and follow the transaction my sent bitcoins remain in that address. How do i get them back ? Any help would be awesome.


texts:
caling getDepth.php I stumbled on some data that contains bids that are higher than asks. That can be seen in orderbook data with the following unix timestamps (for getting human readable date use $date -d@[unixtime]):
1325249854
1325249914
1325249975
1325319825
1325441984
1325545019
1325595982
1325597938
1325625735
1325645568
1325660473
1326656827
1328089365
1328089676
1328089737

So does MtGox stream "orders as arrived" without any processing or is this some kind of anomaly? From 6. 2011 till 9. 2012 with about 3min resolution I counted around 300 instances of such anomalies. Any thoughts on what could be going on? Is this common for other exchanges?


texts: I forgot what wallet is connected to an address. Is there anyway to figure out at least what wallet i used ?

texts: I had to put in an address on a site in case of returns or what not. i use multiple wallets since i have multiple accounts. One of my first accounts received a return and i can not figure out what wallet i used. It is a web wallet which i have narrowed down to three possible sites. I found the address that the money was sent to but is there anyway to figure out what wallet just by using the address attached to the account? i have the public,private, and encrypted keys to each of the 3 wallets that i use. is there anyway to find it using one of those keys? ( no i am not dumb enough to give my private key to anyone)


texts: How do internet wallets connected to full blockchain nodes

texts: How do internet wallets such as Coinbase connect to the a blockchain node? Doesn’t the node itself create a default wallet object on startup? How is this replaced by internet wallets which hold multiple address until account credentials.


texts: How to properly backup a address with private key after 'addwitnessaddress' command

texts:
I've received my balance to my addresss that starts with 3 which is after 'addwitnessaddress' command.

I'd like to know that how do I properly backup my balance to keep safety.

Bitcoin Core has a function that called backup wallet to the 'wallet.dat', but there is a in unexpectable case by file corruption.

I tried keep it save by using 'dumpprivkey ' to get my priv key.

But the console says, "Address does not refer to a key". So I googled it and found it has related with something called P2SH.

It's little bit hard to understand for me to use Bitcoin.

Can some help me out to backup my balance only using by Bitcoin Core client instead of 'wallet.dat'?

Thanks!


texts: Why so many transaction send bitcoins to the sender?

texts:
While browsing the blockchain I noticed that there are a lot of transactions that send bitcoins to the sender (most part of the transaction) and a tiny fraction to another address.

E.g. this transaction sends more than 99% to the sender and the rest to another address.

What is the purpose of those kind of transactions?


texts: Are transactions containing zero-value output accepted by miners?

texts: Would miners generally accept a transaction that has one of its output values set to zero? Can the acceptance in this case depend also on the scriptPubKey associated with the zeroed output?


texts: What is the current (Feb 2012) "bus factor" of the standard client?

texts:
Bus Factor (Youtube) is the

  total number of key developers who would need to be incapacitated (as
  by getting hit by a bus) to send the project into such disarray that
  it would not be able to proceed

What is the current bus factor of the Bitcoin standard client?


texts: When will the Bitcoin Cash difficulty adjust next?

texts:
Bitcoin Cash adjusts its difficulty downwards if there is, roughly speaking, a 12 hour gap between blocks. At least that's my understanding.

Difficulty has dropped to about a quarter of what it was because if that and more blocks are coming in now.

Does this not mean that the new difficulty rules will no longer be triggered now? It seems difficulty has adjusted enough to never again trigger the rules with high likelihood.

That would mean that the next difficulty change happens through the regular mechanism. This regularly happens every two weeks but because the hash rate is still so low it could be far longer than that.

The last 30 blocks took about 21 hours. Normally, 21 hours would have produced 126 blocks on average. So it seems the speed we are seeing is roughly a quarter of the normal speed despite the lower difficulty.

And that seems to imply that this difficulty period will take roughly 8 weeks to complete assuming that the hash rate on that chain stays the same.

Is this assessment correct?


texts: So let's say I'm developing a mining device that has some basic Ethernet or Wifi capabilities, but defiantly cannot run bitcoind. Let's also say that this device is open-source, so I cannot host a server for all of everyone. Is there some server somewhere that is running bitcoind that all of these devices could access (for free) or are there only paid options?


texts: What is the safest way to rename my altcoin from "bitcoin" to "myaltcoin" in the source code?

texts:
Some Context

I am creating my own altcoin for learning purposes and have successfully built the bitcoin code from source with my own genesis block.

Now is it time for me to change the name of the coin, so that it is truly my own alt coin.

To do this, I presume that I must change every instance of bitcoin to myaltcoin in the code, so that when I run bitcoin-qt (after the change I hope to be able to run myaltcoin-qt), everything inside the GUI will say myaltcoin and not bitcoin.

How I propose to do this...

I figure that the best way to do this would be to do some kind of case sensitive find and replace, to recursively go through all files and directories and the strings in the files, changing every instance of bitcoin to myaltcoin

The Question

What is the safest way to do this in the linux terminal? To do this safely I assume I must:

Account for case sensitivity.
Replace file names of bitcoin to myaltcoin
Replace text instances of bitcoin to myaltcoin within files
Replace bitcoin to myaltcoin in directory names

I presume there is some way to do this with find, but I'm not sure what the best way is.


texts: What is the probability of different public key hash that produce the same checksum value

texts:
checksum = 1st4byte(sha256(sha256(PubKeyHash)))
checksum1 = 1st4byte(sha256(sha256(PubKeyHash1)))
What is the P(checksum == checksum1)? where PubKeyHash != PubKeyHash1
Is it 1/(2^^32)?


texts: All the full nodes in Bitcoin network validate a new block as soon as it is mined and propagated on the network, by verifying the nonce and the resulting block hash.  Now the question is that, Do full nodes validate each transaction in the Block, based on its complete history of input and outputs to check for any error?


texts: Pushing tx to the network via AJAX, without installing bitcoin

texts: Is there any web service anywhere that allows me to push raw transactions to the network via an ajax call? Blockchain's pushtx only works if you copy/paste so I can't build around it.


texts: How to broadcast a transaction anonymously

texts:
Is it possible to broadcast a transaction to the network without revealing my personal IP address? My first guess is to connect bitcoind over Tor with proxy=127.0.0.1:9050. Is it the good way to do it or do I have other options?

Thanks.


texts:
I was wondering how it was possible because of the following thinking:

Let's assume that Bitcoin Cash's hashpower is smaller than Bitcoin's. Then they would start mining at the same point in the Blockchain and one of them would find the next block. If it were Bitcoin's, both would mine from this new block because both would accept the new block. If it were Bitcoin Cash's, then Bitcoin would ignore the new block and a fork would happen.

But, as Bitcoin would, on average, find more blocks than Bitcoin Cash, and their blocks are accepted by Bitcoin Cash, the fork would never really occur because the longest valid chain would be Bitcoin's.

Bitcoin Cash miners would be flipping between their and Bitcoin's blockchain.

What am I missing?


texts: Will mining Bitcoin slow or stop other computers on my home network? My son wants to set up a computer to mine Bitcoin but I have a daughter that attends a virtual school and uses the internet. I have charter with 30 mb/s


texts: How do I view the "change" addresses in my wallet? listreceivedbyaddress 0 true doesn't work

texts:
I just sent a test account 5 BTC. I see in the output 1.38BTC was "change" and needs to be sent back to my wallet.

Where can I find the contents of 1F39Qj4E3HnbnyYgan5CZa37spGfHro8eK, and was expecting to find it there, but I typed listreceivedbyaddress 0 true and don't see it


texts: SPV Bloom filter construction, are false positives taken from the blockchain or just due to matching with other addresses

texts:
It is my understanding that the false positive addresses generated by an SPV bloom filter do not need to necessarily be on the blockchain (ie. be addresses that have been used already).
Is that a correct way of thinking about SPV bloom filters?


texts:
I run a site which is essentially an e-commerce platform where buyers connect with sellers and all transactions happen in Bitcoin. I worry about sellers on the site continuously buying their own items on the site to gain visibility (more sales means higher ranking on the front page).

Is it possible to detect whether an incoming transaction originated from the same bitcoin wallet?

I am thinking that I could run a tree/graph traversal of transactions starting at a given payment address and see if I end up at that same address again. But I'm not sure how this would work with wallets where each payment generates a new address from a master public/private key pair. As far as I know, it's not possible to tell whether two addresses originated from the same MPK.

PS: Maybe wash sale is not the correct term here.


texts: Any documentation available that would help developing a Bitcoin Client?

texts:
I want to start developing a Bitcoin Client in a new language. For this I'm looking for references and resources that could be used to as a guide. Some kind of comprehensive guideline of what a client should include. But haven't been really successful so far. Does anybody knows about something like this?

EDIT:
I'm aiming for a full node with wallet capabilities


texts: Zerocash: how to verify that a mint transaction is correct

texts:
I'm reading the whitepaper of zerocash and I don't understand how a mint transaction works. Here are my following questions:

How do you prove that you have enough bitcoins to form a certain amount of zerocoin?
How are the bitcoins locked? What makes you not able to mint bitcoins and using both zerocoins and bitcoins (doubling the value of your bitcoins)?

As an example of the last question, let's say I have 10BTC, I create a zerocoin worth 10BTC, I send it anonymously to Alice, then I make a traditionnal bitcoin transaction of my 10BTC to Bob, what makes this impossible?

If you can't spend the 10BTC anymore (before it has been trasnformed into zerocoin), does that mean we can know how much coin you have minted (eventhough we cannot know how you have spent it)?


texts: Is it posible to create a transaction output that can either be reddemed by privK of Addr A or by privK of Addr B AFTER certain blockheight?

texts:
I am thinking about how to secure your Bitcoin savings.

One idea I had was to create sort of a "backup" address B for an address A which stores the bitcoins. So what I want to achieve is that you are able to spend your bitcoins with the private key of A at any time. But in case you lose access to the private key of A you are also able to spend the bitcoins with the private key of B but only after a certain amount of time (i.e. blocks) has passed.

Would something like that be possible with the Bitcoin scripting language? And if so, how would one achieve this?

Thanks in advance.


texts: Can there be a half segwit, half normal Bitcoin transaction?

texts:
I was wondering if it's feasible to compile a bitcoin transaction that is somewhere in between (segwit and non-segwit), maybe one of these scenarios. I'll call the non-segwit inputs, normal inputs just for the sake of simplicity.

Use one normal UTXO input and one segwit input
Use Segwit inputs but have normal outputs
Have a transaction with two outputs, one Segwit and one normal

If the answer to any of these is yes (maybe doesnt apply to the last scenario), what would be the case for transaction malleability? would the final transaction be still vulnerable to transaction malleability as the signature is still in the main transaction object?


texts: What will happen to bitcoin if the world population increases?

texts:
I've been trying to find an answer to this question but without success. I have a question on scaling, but not of the technical kind.

Assume that the entire world switches to using bitcoin as its only form of money. What will happen with the fixed number of 21 mil bitcoins in an ever increasing population on the globe?

Will they just distribute thinner and thinner to all the people? Will its value increase? Will people just get paid a salary of 0.0000000132 BTC (or similar) in the future?


texts: Bitcoin Core - Go back to a specific block?

texts: I have a full node of Bitcoin Core wallet. I would like to know if it's possible to delete data after a certain block. For example Bitcoin is currently at block 504385. There was a fork around block 500000 and I would delete all block data after that so I can use the blockchain data I have with the new fork wallet.


texts: Find used addresses of an HD wallet xpub (Extended private Key)

texts:
End goal is to find all used addresses of a xpub programmatically, in batches, by querying a local node.

This PHP tool ( https://github.com/dan-da/hd-wallet-addrs ) extracts 'normal' addresses from an HD bitcoin wallet . Now I have to query a local bitcoin node to find out whether the extracted addresses have been used or not.

Whether an address has been used or not can easily be found out by querying the node one address at a time ( https://bitco.in/en/developer-reference#getreceivedbyaddress ). Which works but is too slow.

How can the same be done in batches ? i.e is there a Core function call or something to check info about a group of addresses ?

or any other way this can be accomplished ?

Thanks


texts: Does the ZeroCoin protocol fulfill its promise of anonymity?

texts:
Zerocoin is a new cryptographic extension to Bitcoin that (if adopted) would bring true cryptographic anonymity to Bitcoin.

Has anyone seriously analyzed the protocol and verified it works as advertised?


texts: Litecoin explorer that accepts M-prefixed segwit addresses?

texts:
Just realized that the litecoin explorer I was using (blockcypher) doesn't allow me to input M-prefixed segwit addresses (more info).

Any other litecoin explorer that can do this?


texts: What does the version number in the blockheader represent

texts:
While looking up how a block get mined I stumbled over the version number in the header - which is used to "keep track of changes to the protocol".

But even in the last 5 blocks of the chain (at the state of writing) there were 4 different version numbers - so my questions are:

"What does the version number represent?" followed by "Will a mined block with a random version number get rejected - or could a miner simply use it as an extension of nounce (and thereby effectively double the length of the nounce)


texts: In his recent paper, Vitalik often mentions the term "honest nodes". What do we mean by that exactly?


texts: My unconfirmed BTC transaction on blockchain just disappeared

texts: I had an unconfirmed BTC transaction on blockchain.com for about 2 days plus and now I log in and there's no transaction again. I checked blockchain.info using the hash; all wiped nothing is showing, my BTC is gone. Please what should I do? Blockchain support aren't responding either.


texts: Is there a reliable source where I can download the blockchain as a text file?  Or perhaps is it included in my bitcoin-qt folder after it synchronizes with the network?


texts: Why might MultiBit not show a transaction that was sent to me?

texts:
So i recently bought a bitcoin from a vendor , and i had it sent to my Address in multibit.

Now the problem is , the money isn't there and i'm not sure what to do.

He told me to get bitcoin (program) and now it's starting to download a chain. Currently it's at 95000.

I'm not sure what to do exactly , as i'm worried i may have lost my funds.

What can i do at this point? Do i wait till the Blockchain is finished or should i import my wallet from Multibit to Bitcoin?

Thanks guys!

-D


texts: Basic point multiplication with G in libsecp256k1

texts:
I'm trying to work out a minimal example with the bitcoin core secp256k1 library but am a bit lost due to the many options available. Concretely, I simply want to use libsecp256k1 to multiply the generator point G as defined by the standard with an integer k, ie H = k*G.

So far, I found secp256k1_scalar_mul, which multiplies two scalars and secp256k1_fe_mul which multiplies two field elements, while close neither is what I'm looking for. So I was wondering if someone could point me to a suitable function in libsecp256k1?

Thanks!


texts: How do I import my 12 Breadwallet seed words into Electrum?

texts: When I write them into Electrum during the restore from seed box, the Next button is disabled.


texts: Hard time distinguishing change and withdraw amount for P2SH address

texts:
I am trying to extract the exact amount of BTC deposited and withdrawn from BTC address (from hardware wallets like Trezor, ledger nano, ...). So if the address is pay-to-pubkey-hash then I can easily track amount through its transaction id hash -> outputs   BUT when the address is pay-to-script-hash then I am having a hard time recognizing which one is Change and which one is withdrawing amount from Txn Hash detail. Is there any way to distinguish change and withdraw amount for P2SH address.
eg:
P2SH: https://api.blockcypher.com/v1/btc/main/txs/87d5fa33ae3f1754bb1618c8559b8451f64de1e396627fad65a19b74b2c72b86 ( difficulty finding)

https://api.blockcypher.com/v1/btc/main/txs/d7cdb1f910ac15d99ee98a28c276ccfccd5fd6592cf01528eb57a871e789b709 ( This is easier as output is withdraw amount)


texts: Any exchange available for using virtual cards like Payoneer?

texts:
Is there any bitcoin exchange available for trading bitcoin with virtual cards like payoneer? I know there is coinmama and locabitcoin, but they are mostly P2P. Is there something like cex.io ? Unfortunately cex doesn't support virtual cards.

Thanks.


texts:
The way I understand mining is that you hash the previous block hash with the new transaction files and a variable to get certain amount of zero in the hash. So the stronger your hash power is the faster you find the new block hash. My problem is that thinking about it this way means that only the one with the highest hashing power will find the block first and get rewarded, then what are the others with lower hashing powers doing ? and how do they get rewarded ?

and do you get rewarded when you find the hash or you get rewarded every second of mining proportionally to your hashing power ? because the websites that offers hashing powers shows your balance to be continuously increasing and not as expected to increase step by step with each hash found.


texts: What are the mining spec differences between Bitcoin and Litecoin?

texts: Obviously, Litecoin mining requires less computational power as it it more CPU friendly, but does this mean that if you switch a GPU Bitcoin miner To Litecoin mining you will be wasting your resources?


texts:
Are there any ways to avoid limitation for api calls (5/sec)?

I need the info about transactions and balance (of certain account), UTXOs and the ability to broadcast my transaction.

Currently I am using public blockchain explorers such as

https://www.blockcypher.com/

https://chain.so/

https://etherscan.io

However they have limits on their calls, which is unacceptable for cases if my service in use of at least 1000-2000 people.

I am begginer, so after some surfing I understood that the only way to tackle that issue is by saving the info in my own database or run my own full nodes (for each currency I have - eth/etc/bitcoin/btc/doge/dash.. etc)
which might be pretty expensive and time-consuming.

Can you suggest any good solution?

Thank you!


texts: Mining for nil-transaction blocks only - gaming the incentive scheme by rogue miners / consortium?

texts:
I understand that there is incentive to include transactions where the output is less than the input so that the block creator can pocket the difference. But I'm wondering if that is really worthwhile in terms of hashing rate?

I know that overall having transactions is a good thing for the currency, but what if a particular miner only cares about their block finder's reward?

This is my understanding of the hashing process:

SHA256 process (image from Coursera Bitcoin course)

The hash input is split into 512-bit input-blocks, and then the compression function (in yellow) is run once for each input-block (including the output of the previous result).

Assuming that the smallest possible bitcoin-block is < 1024 bits (please correct me if I'm off), then hashing for no transactions will take 4 compressions.

AFAIK, the largest block size is 1MiB, or 8,000,000 bits, requiring 15,625 compression functions, more than 3,900 times longer than for a nil-transactions block.

Will it will take about 3,900 times as long to hash a 1MiB block as to hash a nil-transaction block?
If this is correct within an order of magnitude, then wouldn't it be better to increase the probability of finding a block approx. 3,000 times rather than collecting one block's worth of transaction processing reward?
What is the average transaction fee collection per block?
What if a small consortium of miners took up this strategy for personal profit, riding on the backs of the miners who cared about the ecosystem as a whole and kept it afloat?


texts: How is my real identity linked to my bitcoins?

texts:
I am new to bitcoin and would like some clarification on its anonymity.
Example: i buy bitcoins from an exchange and send them to my bitcoin wallet.
The addresss that i sent the bitcoins to would be linked to my real identity, i get that part, but what if i create a new address? Or create an entirely new wallet? Would that address in any way be linked to me? Currently it seems to me that the only way to be anonymous, is to buy bitcoins themselves anonymously. Thank you


texts: Someone deposited money into my blockchain wallet but says I must check on my Bitcoin address spam. Where is that on Blockchain because it does not appear on my transactions.


texts:
sorry for the stupid question but I can not understand that I have missed.
I'm trying to use the wallet for removing unused addresses. I get a message has been deleted successfully, but the client I still see those addresses, it seems that the removal does not work. Maybe I missed something, please help.


texts: Test environment for bitcoin transactions/wallets

texts:
I want to build a pet project which would use bitcoin for sending/receiving and see balance of wallets involved changed.
What are my options for having a local env that would allow me to perform these operations in a way similar to real environment?


texts:
I'm running a docker image with a bitcoin node (version v0.16.3.0-g49e34e288) and it's taking more than week to synchronize, having only synchronized 54% of the blockchain. I'm running it with the "prune=550" and "disablewallet" options. I there any way to speed up the synchronization process?

Thank you


texts: Do you sign only the previous output of transaction?

texts:
I need to confirm that I understand how transactions work in the Bitcoin network. Ok, so:

Alice is a network node. Alice wants to send bitcoins to someone in the network. Alice is creating a transaction using her wallet.
Every transaction has inputs and outputs. The inputs of every transaction are just references to some previous outputs of some other, older transactions that previously sent funds to Alice addresses.
To send bitcoins Alice needs to resolve the puzzle given in the scriptPubKey of a previous transaction's output by using her scriptSig which her wallet generates upon making a transaction. Basically Alice just needs to prove that she is in control of private key (related to address previous bitcoins were sent to) by signing the new transaction.

Did I get these steps right?
My confusion started when I was exploring the hash type because I saw many sentences that said the Output of a transaction is signed correctly. With my understanding (from above) I assume that the previous output is signed correctly? And therefor, an input of a new transaction is considered valid. But I couldn't find confirmation for this. Am I missing something? Thank you!


texts:
I am running GUIMiner and Triplemining server. I currently have just under 100 "shares" accepted.

What does this mean? What are accepted shares used for? How do accepted shares relate to "blocks"? How does this relate to a Bitcoin?


texts: How to upgrade the current installed Bitcoin Core on Ubuntu to the latest version (0.21 v)

texts: Just wondering how can I securely upgrade the current version of my Bitcoin Core to the latest released version without losing any data. It is all installed on a Ubuntu VM. The instructions I found are like downloading and installing the new version regardless of the existing one. Thanks in advance.


texts: How blockchain.info calculate the value transacted

texts:
Having this address: https://blockchain.info/address/19tqZYnP9youKtbene2FZiZtZyJYaLeBDw

The last transaction says that this address received 0.0236 BTC

But even knowing the value in and the value out I am not able to calculate that value:
https://blockchain.info/tx/831c976cb54f27e5a496db749fc9e865c8e077006225d1dfaf61d998fe5a3186

In:
---
15Rhv2dsEjFaHzMhPsjGmFxgqCRhCmggjj (0.04583825 BTC - Output)
13LwYeB93Bmo2aWqGyK1ybtF9JiupPFVey (0.029625 BTC - Output)
1BxdV34eTe1YJBJpScGx6jRRVDQBeRf5qj (0.00696224 BTC - Output)

Out:
----
1BTvKHzbfm3RjPMxDZSsG2YYuaEHgfdJNP - (Spent) 0.00045884 BTC
1NCLWFw6F2nJ2pgBWy96K37rbx7VSLZs66 - (Unspent) 0.00239111 BTC
1D7BNbWBPuL22TW6WuoSq5sRrbPAxeJw8g - (Spent) 0.0156 BTC
19tqZYnP9youKtbene2FZiZtZyJYaLeBDw - (Unspent) 0.0236 BTC
1wLbaePtYhh2t5Cgd5NF59LX6Pooe1yLH - (Spent) 0.00920259 BTC
3HXAkXTYvtLzYuudDfNZBMSoueUtvdwXAz - (Unspent) 0.03036754 BTC

What I tried is sum all the In's and then substract the Out that has been spent and the fees.

What I am doing wrong? How I can calculate 0.0236 BTC


texts: How can you make sure that there will be routes with large enough balances to handle transactions?

texts:
I'm creating a "Megathread" regarding the Lightning Network and have been fielding questions. To help obtain the correct answers with sources, I'm reaching out to the Bitcoin StackExchange.

I was asked to make a separate post for each question.

Thank you in advance for helping the community understand more about this great technology.


texts: Unexplained Segwit transaction results in wrong balance (mixed address transaction?)

texts:
I sent 0.005 BTC from my Ledger Nano wallet (Segwit) to my Bitstamp wallet.
When checking my new balance on a public address reader, an additional 0.603 BTC was removed. I then checked the transaction online on blockchain.info and the 0.603 BTC went to an unknown-to-me address (I never authorized nor performed this second transaction).
My Ledger Nano wallet (Segwit) balance on my Ledger Desktop app always showed the correct balance (with only -0.005 BTC) when the other sites all showed the incorrect balance ( -0.603 -0.005 BTC).
I finally transfered the total remaining balance from my Ledger nano to Bitstamp as a test, and I got back the 0.603 BTC missing.
What is interesting is that the total of the transaction (authorized
0.005 + unauthorized 0.603) is equal to a transaction I have done two weeks before (from an exchange to my Ledger Nano).

Can someone explain to me what happened? By not understanding what happened, I am fearful of other unexpected transactions and wonder if I should still use my Segwit address.

Thank you


texts: Txindex=1: how to recognise the blockchain with this option?

texts:
This might be a dumb question: I started the Bitcoin daemon for an initial blockchain download. It immediately started downloading, I edited the Bitcoin.conf file with txindex=1. Stopped and restarted the daemon. How can I be sure the blockchain has txindex=1 correctly set? Should I reminded with the command line Bitcoind -reindex

How can I understand “looking” at a blockchain (day I downloaded from a torrent) that has txindex=1? Thanks


texts:
It is De facto standard that address should not be reused, and even Bitcoin officially emphasis address should not be reused. Does the same condition apply for Multi-signature address ?, If Yes apart from privacy what is the need ?
Thanks


texts: In Pieter Wuille's presentation on Segregated Witness, he often mentioned "fraud proofs". What exactly are they? Do physical users actually have to go out of their way to manually produce these proofs to alert other nodes of misbehaviour? How do fraud proofs relate to witness scripts?


texts: What does it mean ''Unconfirmed change may be issued''?

texts: After i send some BTC the left over BTC came back and goes to a new Address in my Wallet, how come ? What does it mean ''Unconfirmed change may be issued'' ?


texts: If we know transaction ID can we check more info about it on the web?

texts:
Just curious?

I mean are there ways to see that info publicly?


texts: How long does it take for an unconfirmed transaction to drop from the mempool?

texts:
I have a transaction currently in unconfirmed limbo for 24+ hours. It was from an old 0.15 bitcoin core wallet, and I guess the fee was set too low. The old version of bitcoin-qt does not support replace by fee, so I have attempted to issue a double spend with higher fee. The double spend is not being picked up though, and the transaction id does not show up on any block viewer sites.
Will the original transaction drop from the mempool after a certain time period? Is there another way to issue the double spend to make it work and take precedence over the original?


texts: How can I import my public key from a mnemonic seed phrase to receive a payment?

texts: I installed Trust Wallet on my Android smartphone. I carefully wrote down the reminder words in the proper order and hid them. I know where they are.  How do I use the words to get the key (public or private) for receiving bitcoins into the wallet from, say, Coinbase?


texts: Android Bitcoin Wallet, zero balance after keys import

texts: I imported all my private keys (including those of change addresses) to Andreas Schildbach's Bitcoin Wallet  from bitcoin-qt and my balance is still zero. This disagrees with Blockchain, which clearly shows non-zero final balance. What is the reason and how can I fix it?


texts: Help With Raw Transaction Fee - Absurdly High Fee

texts:
I've been working on my Litecoin wallet for a while now. But I can't seem to control the transaction fee when I make raw transactions.

I know how to send transactions with Litecoin-Qt GUI:
https://live.blockcypher.com/ltc/tx/2b2f0aab9d2661840a60b172dcda24f359e85b7dbd0810e7afb2d3a6c0b8e59c/

No problem with that, the fee was 0.00017 LTC and was included in the next block. The vsize of this TX = 170, which explains the 0.00017 LTC fee.

But I'm also working on my own wallet on my VPS with the Litecoin-CLI. I made a raw TX, signed it and sent it. This happened:
https://live.blockcypher.com/ltc/tx/32ceefc7f377ad53c91922dffe62e6fd19e48a46d6afb4d610c2c090646404dc/

A transaction fee of 0.1 LTC!!! And the vsize is just 192.

I went back to the litecoin.conf file and it has the paytxfee=0.001 parameter. Which means it would cost me 0.001 LTC/kB. maxtxfee wasn't turned on yet, but now it is with a value of 0.001. When I try to send now, it just prompts me with: "error":{"code":-26,"message":"256: absurdly-high-fee"}.

What am I doing wrong?

(Yes I'm testing my wallet on the mainnet, I'm stupid)


texts: I'm trying to find out if I invested in bitcoin years ago, how can I find my bitcoin?

texts: For whatever reason I remember investing in bitcoin when it first got started, unfortunately I don't have my old computer or old files anymore. If there is anything you could do to help that would be wonderful. Thank and have a great day.


texts:
I'm using the blockchain API to make a "send to many transaction". In the recipients I only put other people addresses, but somehow the API sends the remainder of my balance back to me.

For example:

  https://blockchain.info/tx/b4c3203815fdf61616c0a2358fa0388e734bf53503f0a659d3c9fc7863da8adc

I had 0.01 btc in my wallet. I sent 0.0000543 BTC to two different recipients, but somehow my whole balance got spent and my 0.0097914 BTC got sent back to me. I didn't ask for this.

EDIT: It also happens on a singular transaction:

  https://blockchain.info/tx/2eb4273313e27c2ede86844c58f687dc535aeaa5207e9a9c4a526a032cd5143a

I've inspected the API calls and they are correct. My address is no where to be seen in it.

Why is this happening?


texts:
How to create, sign, and send a transaction using electrum wallet RPC ?

I have experience create/sign/send a transaction using bitcoind wallet since I just have to using bitcoind RPC. But on electrum I couldn’t find that the RPC command to do that.

The only thing I want is send bitcoin from electrum wallet but from specific addresses.


texts: How do exchanges store and transfer bitcoin?

texts:
When I buy bitcoin on an exchange I instantly get them and can withdraw my coins 5 seconds after the transaction. This means the exchange must record your account balance in some database independent of a bitcoin wallet (otherwise buying the coins would take ~10 minutes) and when I withdraw them it is sending a request to withdraw X bitcoin from the exchanges wallet.

However, when I check the wallet that BTC is coming from on blockchain.info etc the source wallet is always different, and I'm unable to see what wallet's balance over time.

How are exchanges storing bitcoin so you can buy/sell on the exchange instantly, and how are they managing that system for withdrawls?


texts: I generated a paper wallet. Then search Blockchain.com with the public key. There are 2 blockchain results with same public key. 1) BTC address and 2) BCH address. This is confusing. How can I generate a public key that is only for BTC address?


texts: How can I check what mining algorithm does an altcoin use?

texts:
Where in the sourcecode files can this be checked?

For example, lets get a specific coin:

Chronon
https://github.com/ChrononGroup/Chronon

In what file can one check the mining algorithm?


texts: Is there any way to find out latest bitcoin transaction of a particular address in bit-cli, without knowing the txid?

texts:
I would like to find out the immediate last transaction of addressA.

But so far, I can only do this, bit-li gettransaction <txid> then bit-cli decoderawtransaction <hex>

But I want to do something like this:

bit-cli lasttransactionto <addressA>

How can I do that, without knowing the tx id??


texts: How can I make MultiBit go one year back and then replay the blockchain?

texts:
Like a year ago, I got a some bitcoins. I was using Bitcoin-Qt back then. Because reading the whole blockchain since then takes a lot of time, I got MultiBit, created a new wallet and imported my private keys from Bitcoin-Qt.

The problem is that MultiBit only goes back a few days (looks like one day before I created my wallet in MultiBit) to replay the blockchain. So the balance shown is wrong. The function "Reset Blockchain and Transactions" doesn't help.

How can I make it go one year back and then replay the blockchain? At least I think that's what I need, I just don't know how.

Thanks in advance.

EDIT:

Thanks for the help. Yes, I have imported them all. I've just reset again. I see that MultiBit goes back to November 2013 and starts replaying the blockchain from there. But that's just too late. It should go back to January 2013 instead. I just double checked one of the receiving addresses on blockchain.info. The transaction took place on 16th of January 2013 and the money from that address hasn't been spent yet.


texts: Do you need multiple wallets to manage your cryptocurrencies?

texts: I was wondering those who have many different coins, do they need multiple wallets? or one wallet with that supports different coins is enough.


texts: Have the Bitcoin developers resigned to the idea of changing the mining algorithm to an ASIC-resistant one?

texts: Mining centralization is a big Bitcoin problem, and the development of ASICs is one of the main causes of this, but I haven't found a lot of discussion about changing the mining algorithm to a more ASIC-resistant one. Is this because there is some kind of contract between the big miners and the Bitcoin developers, to not change it ever? Or there is some work in progress?


texts: If a fundamental bug is found in bitcoin does that mean that the only way to patch it would be a hard fork? I'm confused at how this software that only has one version is running for 10 years without even a bug?


texts:
according to bip39, I maked 12 mnemonic words and then get a 512 bit seed from them.

now I want to know how must I convert this seed to private key ?

what functions must I use ?

please introduce me libraries for browser javascript.

although I know that I must use ECDSA and secp256k1.

but I do not know exactly what the steps are?


texts: Is pruning of the merkle tree implemented in the bitcoin android wallet?

texts:
I know that satoshi's client doesn't prune, because we need to store all the transactions so that we can send them to other nodes.  But does this android bitcoin wallet from de.schildbach prune?  Space on a smartphone is at a higher premium so it seems like a good place to prune.

And how much space would pruning save?  Has it ever been checked?


texts: How to get total transactions on the network with RPC

texts:
I have seen no concrete answer to this question anywhere.
I assume it is possible to get the total number of successful transactions on the bitcoin network using bitcoin-cli command because most explorers provide this information.
How can i get this information from a fully synced node?


texts: What is the difference between "time" and "timereceived"?

texts:
https://bitcoincore.org/en/doc/0.20.0/rpc/wallet/listsinceblock/ :

"time" : xxx,                        (numeric) The transaction time expressed in UNIX epoch time.
"timereceived" : xxx,                (numeric) The time received expressed in UNIX epoch time.

What?
In the output, every single "transaction" appears to have the exact same time and timereceived timestamps, killing my theory that time meant when the transaction was sent and timereceived referring to when the local Bitcoin Core first "saw" it.
It feels like I've asked about every single little part of Bitcoin Core online by now. I cannot fathom how anyone can get anything related to Bitcoin done when the documentation is this nonsensical/nonexistent.


texts:
On testnet I sent a transaction

I believe this was for TBTC1.000 and a 0.0001 fee: i.e. inputs - outputs = 0.0001.

When I try to claim the transaction I am only allowed to claim 1 - 0.001. If I claim (what I expect to be) the full amount (TBTC1.000) I receive an err #26.
If I claim TBTC0.9999 everything works

I presume I'm doing something wrong, and would be happy to understand what that is.

Thanks for any suggestions


texts: Why do some transactions have more than one input?

texts:
I know a normal transaction has 1 input and 2 outputs (if there is change that is the second output).

But what about this scenario?

Lets say I'm withdrawing bitcoin from my gemini account and want to calculate the fees. How would I even know if it's 7 addresses sending (which would make the byte size of the transaction larger = higher miner fees) or just 1 address sending?

To further elaborate on test-net here is our system with withdrawing btc to another wallet:
https://test-insight.bitpay.com/tx/8bc3db6a4a119e369752a52f0be39ae3a4d579adcdc49e9d92429b920000f934
https://test-insight.bitpay.com/tx/553a27e38a73ed90c792b70add3c3f894e94955440205917ee754787c17ea62b
https://test-insight.bitpay.com/tx/cecf112c7e3494826b165f4bcbeca9ef20cc800dce3d433c04b070e4fbc1da81

Here is when I deposited back into our wallet (from copay wallet that supports test net):
https://test-insight.bitpay.com/tx/5871e5957ef6ec67a336de01e6f3e4f6f4cffd9986d2f5db181fdcbf6b00d1e0


texts: How would a centralized block chain work?

texts:
If I'm a company who pays my employees and my supply chain with my own currency created on a block chain and they can spend it wherever it is accepted, would I need a POW or POS scheme to maintain the veracity of the ledger of transactions?  Or is there a way to validate the transactions and history of the ledger via centralized control?   Could it work like this:

Only my company could create my currency, so there's no way to counterfeit it.
Everyone who accepts my currency uses software at the point of sale that verifies the transaction and the history of the ledger.
Each unit of currency is embedded with personal ID that transfers to the next person with their personal ID until it eventually recycles back to me, the issuer.

Would I be able to eliminate double spending and fraud in a centralized system without the miners?


texts: getheaders request being ignored by peers

texts:
It seems my 'getheaders' request is being ignored by peers. I've followed the implementation: https://en.bitcoin.it/wiki/Protocol_documentation#getheaders without success.
If I change it to 'getblocks' then it returns an inv[500] message just fine. But for some reason, it's not returning a 'headers' packet when requesting headers.
I'm connected to over 100 peers, and still no success.
Has anyone else had similar trouble before? Any guidance is appreciated.
The request values are as follows:
    magic=3908297187
    command=getheaders
    length=69
    checksum=1021834552
    payload=[version=70013, hashCount=1, blockLocatorHash=[00000000839a8e6886ab5951d76f411475428afc90947ee320161bbf18eb6048], hashStop=0000000000000000000000000000000000000000000000000000000000000000]

and the encoded bytes are:
e3e1f3e876657273696f6e000000000069000000a4d49d4e7d11010004000000000000002cb0db5d73010000000000000000000000000000000000000000ffff7f000001208d000000000000000000000000000000000000ffff0fa518f420a100ecfbdaa2585542132f626974636f696e6a2d73763a302e302e372f0000000000

Just to note, when serializing, i reverse the blockLocatorHash bytes as mentioned in the wiki.
Cheers,


texts: Problem mining Genesis Block in Dash Clone

texts:
Good morning, I need help !! I have cloned other coins (scrypt and SHA256), but I found a big problem with the DASH CLONE.
After having completed the DASHCLONE project. When I can not do the genesis block (tried with QT and tried with daemon) it does not mine .........! getgenerate = true, but do not mine!
the log writes this:

CMasternodeSync::ProcessTick -- nTick 1189 nRequestedMasternodeAssets 0 nRequestedMasternodeAttempt 0 nSyncProgress -0.250000

Thank you


texts: Can I explicitly specify a path for Lightning payment?

texts:
From what I understand, in the current Lightning implementations payments work as follows:

calculate best N paths according to some metric (like, total fees);
try to perform the payment through the best path;
if it fails, try the next one, until one succeeds.

Is there a way, using standard APIs and implementations, to specify the path for the payment explicitly? For example, how can I find the best 10 paths and then try to execute the payment through path number 4?


texts:
Kind of a long story, I'll try to be consice -

Back in 2013 I've opened 2 wallets at blockchain.com (back then it was blockchain.info) and I have funds in both wallets.
Tried to access the wallets about 3 years ago. Everything was OK with the first one, but when I've tried to access the second wallet, I did not got the confirmation mail from the site.
After some help from their support, I've figured that I've used 2 different mail accounts to the wallets and I don't have access to the second mail anymore.
I've asked the support team to change my 2FA mail of the second wallet to the mail address that I use today, which they did.
After the change was done, I tried again to access the wallet. I got the confirmation mail, but when I clicked it, the login page displayed the sad message of "Cannot decrypt wallet, wrong password", although I'm sure I have the correct password (read on and understand howcome I'm so sure).
Tried to use the recovery phrase - the recovery page asked my 12 words phrase, while mine is 17 words.
Wrote to the support once again, and they reffered me to a different recovery page, one that uses 17 words, since my wallet is now considered "legacy" wallet.
Recovered the password and guess what? It is the exact password that I have. I've double and triple checked it, but it is the same password.
Once again I've tried the support team, but all the responses that I got where the same - we don't store the passwords and we cannot help you.
Found recently the wallet.aes.json file of that wallet, I've decrypted it (using python script from this site. I've use my password and the file was decrypted correctly, showing my my public address, wallet guid and some other data.

To conclude - It looks to me that something went wrong with the site's copy of my wallet - either in the process of upgrading the site (even though my second wallet is OK), or in the process of changing my 2FA mail address), but they won't help me anymore.
My question -
What should I do next?
I know that there is an option to "import" my wallet.aes file to the site, with this link, but is it the right thing to do? The wallet is already in their database, so can it be "imported"?
Can I import that file to another site and gain access to my wallet?
Thanks :)


texts:
I am planning to write a site that receive payments in Bitcoin.

The client add products to the cart, then during check out I will create a Bitcoin address to let him pay for it (each cart gets a unique address). I found the code to create multiple address here. I plan to use the NBitcoin library.

How do I verify the Bitcoin address has been paid? I'm planning to use a service like blockchain.info, but I only have the following information

destination Bitcoin address (my generated address)
the amount it should receive

Is there an easy way to use blockchain.info to query that my address was really paid using C#? I read the API but it is confusing.


texts: How to use downloaded blockchain on ubuntu?

texts:
I am using a fresh install of Bitcoin and have no wallet with coins at this time, and want to use the Bitcoind service in short time (loading blockchain using bitcoind will take days because of slow pc, can not wait for that also because PC can't run all day). So I decided to download the blockchain from http://eu1.bitcoincharts.com/blockchain/.

But how do you use it? I am using Ubuntu 10.4 and Bitcoin 0.7.0. I already placed the downloaded files in .bitcoin directory and then run bitcoind but then it just started downloading the blockchain from the network, ignoring my downloaded files.

Thank you in advance.


texts: How to generate Bitcoin private - public keys with ECDSA module?

texts: Pretty same question was asked here, but maybe there is a way to generate keys using ecdsa module in just a few lines of code?


texts: Is it faster to retrieve bitcoins from exchanges than fiat?

texts:
Quite often there are threads on various forums and complains on IRC channels that this or that exchange is not "playing nice" and has withdrawals (to a fiat currency like USD) taking a very long time. Very often invariably the excuse is that there has been a problem and that "employees are processing the backlogs" or something like that.

What about transferring bitcoins from the same exchange to your own bitcoin wallet? Is it something that also takes weeks and where the same excuses about backlogs are used? Or are the bitcoin transfer from exchanges to the wallet of your choice something that happens quite fast?


texts: How can I best implement Bitcoin in my business?

texts:
Is there any good tutorial, discussion or implementation of bitcoind for business?
What's the best Bitcoin.conf?
How to expose the Bitcoind API to the internet?
How to guarantee confidentiality, integrity and availability?

Basically I'm looking for advices on how not to turn my small online shop into the new mybitcoin.com :)