texts: How can some exchanges/services afford to pay for customers transaction fees?

texts:
Some exchanges and services (e.g. CoinBase, Bitstamp) pay for the transaction fees for their customers when the customers send bitcoins from their wallet/account.

They might have tens of thousands of transactions going out of customers wallets everyday. The 0.0001btc fees might add up really quickly and become a large cost to them.

Are they making transactions wait so that they can send to many at once? If they have enough transactions going out this might work as the customer won't feel a few seconds of delay.

Or do they create a unique transaction for each? If so, how can they afford it?


texts:
In 2013 I transferred 5,02 BTC to my Bitcoin Core wallet.
My Bitcoin version v0.8.1.0-g34d62a8-beta QT is version 4.8.4

After the transfer I locked the wallet with a password, wrote the password down and now, after 4 years I wanted to send the bitcoins out but it tells me my password is wrong.

I tried several solutions I found on the internet, none of them worked. Do you know a solution? I use both windows and Linuxmint. The wallet was on a Linuxmint computer installed on an USB-stick.


texts: How are SIGHASH flags encoded into a signature?

texts:
This page describes SIGHASH flags:

  OP_CHECKSIG extracts a non-stack argument from each signature it evaluates, allowing the signer to decide which parts of the transaction to sign. Since the signature protects those parts of the transaction from modification, this lets signers selectively choose to let other people modify their transactions.

But how can I extract the SIGHASH flags from the signature?


texts: Segfault when attempting to run cgminer on ubuntu 10.04

texts:
I recently wanted to try mining some crypto-currency, and litecoin seemed to be a good way to start since it doesn't require too specific hardware.
However, running cgminer after install (which was completed without errors) ends in Segfault.

Machine configuration :
Ubuntu 10.04
ATI Mobility Radeon HD 4500 series

I might be missing some packages, since no tutorial has the same list, but since the install didn't complain, I assumed everything was OK.

The steps used so far :

got the cgminer-3.7.2 x86_64.tar.bz2 (seems to be the last that supports GPU mining)
installed AMD APP SDK 2.9
mkdir amdapp_2-9

cd amdapp_2-8
tar -zxvf ~/Downloads/AMD-APP-SDK-v2.9-lnx64.tgz
sudo ./Install-AMD-APP.sh
sudo reboot

installed ADL SDK 6.0

mkdir ADL_SDK
cd ADL_SDK
mv ~/Downloads/ADL_SDK_6.0.zip .
unzip ADL_SDK_6.0.zip
cp include/* ../cgminer/ADL_SDK

installed cgminer

CFLAGS="-O2 -Wall -march=native -I /opt/AMDAPP/include/" LDFLAGS="-L/opt/AMDAPP/lib/x86_64" ./configure --enable-opencl --enable-scrypt
make
make install

did some exports

export DISPLAY=:0
export GPU_USE_SYNC_OBJECTS=1
export GPU_MAX_ALLOC_PERCENT=100

And finally, I wanted to test via

./cgminer -n

That failed miserably, as all I got was a Segfault.

Here is the result of the configuration step :

cgminer 3.7.2
------------------------------------------------------------------------

Configuration Options Summary:

libcurl(GBT+getwork).: Enabled: -lcurl
curses.TUI...........: FOUND: -lncurses
OpenCL...............: FOUND. GPU mining support enabled
scrypt...............: Enabled
ADL..................: SDK found, GPU monitoring support enabled

Avalon.ASICs.........: Disabled
BFL.ASICs............: Disabled
KnC.ASICs............: Disabled
BitForce.FPGAs.......: Disabled
BitFury.ASICs........: Disabled
Hashfast.ASICs.......: Disabled
Icarus.ASICs/FPGAs...: Disabled
Klondike.ASICs.......: Disabled
ModMiner.FPGAs.......: Disabled

Compilation............: make (or gmake)
CPPFLAGS.............:
CFLAGS...............: -O2 -Wall -march=native -I /opt/AMDAPP/include/
LDFLAGS..............: -L/opt/AMDAPP/lib/x86_64 -lpthread
LDADD................:  -lcurl   compat/jansson-2.5/src/.libs/libjansson.a -lpthread -L/opt/AMDAPP/lib/x86_64 -lOpenCL    -lm  -lrt

Installation...........: make install (as root if needed, with 'su' or 'sudo')
prefix...............: /usr/local


texts: Is there any "permissionless" blockchain "without a native coin"?

texts:
We may certainly say that a "permissioned" blockchain cannot have a native coin (or cryptocurreny) since in permissioned blockchain we need a permission to be eligible to participate for transactions validation and so having a native coin in a permissioned blockchain is not meaningful.

However, on the other hand, can we say that having a native coin/cryptocurrency for a "permissionless" blockchain is crucial? Or is there any permissionless blockchain without native coin? In that case, how to ensure security and how to motivate miners/validators for participation in transactions validation?


texts:
Trying to get stratum working on my server.

When I start the server everything looks ok except I get this message:

***** Is service_repository missing? Add service_repository module to your python path!

Clients can connect on port 3333 but instantly get disconnected. I suspect it is to do with the error above.

I cannot seem to find any service_repository - so dont know what path to add to my PYTHONPATH?

Any ideas?


texts: How much space does armory and the latest version of Bitcoin-Qt take up, together?

texts: It seems like Armory and Bitcoin Core are taking up 78GB so far, and it's not even done downloading.  How much more space will I need?  Is it possible to get rid of some of the data after it is all done?   So far the Building Databases step has taken up the most GB.  I'm using it on Ubuntu.


texts: Options for accessing my BTC after host went down

texts:
Years ago I had put BTC into a store wallet. The store went bust and I didn't get to transfer my BTC into another wallet before I lost access to it.
I can still see the balance on blockchain.info and I have the PIN code provided to me by the store to verify my ownership of the coin, but I don't know if I can access it, and if I can, how would I go about it?


texts: I have looked everywhere but cannot find out whether the Black Arrow Prospero X-1 has a USB port for connecting to a computer (and interfacing with miner to start mining). Does it have one?


texts: How to spend from the "master_private_key": “df484533kf5mzv83892a234a44ae9z83m832987a82mqwmdkks018121204v95las9"

texts:
I made a backup of an outdated command line interface BTC wallet, here is an example:
"master_private_key": “df484533kf5mzv83892a234a44ae9z83m832987a82mqwmdkks018121204v95las9"

How can I import this key into another wallet?


texts:
is there a way to have BTC sent from somewhere to my wallet and then that amount is immediately transferred to USD? I know that Coinbase offered this once but they have since removed that feature. I am just wondering if there is a similar service out there.

Thanks.


texts: Withdraw and deposit in cryptocurrency exchange website

texts:
In an exchange website we just book trades in our database and just when user want to withdraw his BTC balance we make a real transaction in bitcoin network for him. Consider a scenario that a user deposits 2 BTC and after some trades he now owns 5 BTC. His public address balance is 2 BTC and server must send 5 BTC to user's address. So server need to do more than one transaction: 2 BTC from his own deposit address and the rest 3 BTC from another address that server manages. In this scenario we must pay fee for at least 2 transaction. We usually in withdrawal take fee just for one transaction from user. The problem is now server must pay the other fees?
What is the solution for this problem?

In BTC scenario I want to use blockchain.com's wallet app api. As I understood, we can have lots of publuic address corresponding to one extended public key of wallet. So we assign each user to a different public address in time of deposit. In time of withdraw, we can pay from blockchain's wallet to withdraw address of user. Am I right about this approach?
I can generate new address of blockchain wallet with "http://localhost:3000/merchant/$guid/new_address" url. But this url just generte BTC address. How an I generate new address for ethereum and bitcoin cash in block chain.com api?

Is it possible to use such this solution for ethereum, litecoin and ...

If not, how can I manage the problem of many users deposits and withdraw in an exchange site?

Excuse me for number of questions

Thank you in advance


texts: How to get the balance of a wallet using only bash interface?

texts:
I need to get the balance of specifics wallets only by using bash terminal tools without installing anything new to the OS (An old customized Ubuntu Server)

Any idea how to do it? Thanks in advance.


texts: Coimarketcap api data different from coinmarketcap.com

texts:
I am using popular Coinmarketcap API request:

https://pro-api.coinmarketcap.com/v1/cryptocurrency/listings/latest?limit=100&convert=ETH

In response percentChangeFor24h and some other parameters are always different from what is show on coinmarketcap.com. Do I miss something or data is just irrelevant? Could it be from timezone? I have not found any way to change timezone into requests itself.


texts: Do miners have to hold all the blocks in memory?

texts:
Running a miner node, one would have to verify transactions. This includes checking all the inputs of all the transactions.

Does this mean that a miner must hold all the block-chain in memory (currently about 8.7 GB)? If not, how can a miner find previous transaction (a transaction input does not have an indication to the block containing it)?


texts: Is there any 'Metamask-like' app for Bitcoin?

texts:
9 months ago someone asked this same question: Metamask-like web3 inject for bitcoin but I was wondering if there had been be any changes since then.
I'm currently looking for a Chrome extension that allows you to validate Bitcoin users based on their wallets, It does not matter if it's not a Chrome extension, I just need some app that could accomplish this.
I'm working in a project using Metamask for login users, and I need to find out if there is a way of archieving this with Bitcoin (and other cryptocurrencies), so if you know something about the topic it would be great to hear you.


texts: Why are transactions grouped into blocks? (how are transactions put into blocks)

texts:
Why are transactions grouped into blocks (PART 3)?

Lets say we have just put a block on the blockchain. Now miners start forming new blocks and try to guess new hash values. The miners are putting transactions into their formed block (with a hash guess)? Which of the unconfirmed transactions do they put into the block (all unconfirmed or a subset)?
Is putting a transaction into a block a way of stating that transaction has been validated? How does this guarantee the transaction, miner put in the block, is valid?


texts: How can I run an Electrum console command from outside Electrum (in Linux)?

texts:
I want to use my electrum wallet balance in my another python application.
How do I make a call to the getbalance() function?


texts: Why does the amount of sats in a lightning payment channel amounts vary if no txns are occuring?

texts:
I recently got my lightning node up and running (went the easy route via Casa node).
I noticed that I was having a difficult time tracking the amount of sats in a given channel..I wasn't doing any transactions with them, but they seemed to vary up and down 1000 sats up, 2000 down, etc.

Confused, I finally opened up a payment channel only to watch it, see how it moves, with a nice round number: 1,000,000 satoshis.

It's still in pending state (trying to open it up with ACINQ node for little miner money, still hasn't been picked up by a btc miner)...anyways..it's still in pending state, but the amount now lists "989,869 sats Pending" not 1 million sats as I tried to open the channel with. . .

Should'nt satoshi quantity stay the same for a given channel (if it's all opened up and no txns are occuring, or if as in my case it's in pending state?). Does the bitcoin price going up or down affect the amount of btc/satoshis in a channel?


texts: Why don't addresses in an (unencrypted) wallet.dat file seem to match addresses that would be generated by the private keys in the wallet?

texts:
I've been messing around with an empty wallet file using the 'pywallet' utility, and have come across something I can't understand.

A dump of the unencrypted wallet readily reveals a list containing entries such as:

        "addr": "1NpYUPpz2E4fhYfoJRfUApa5hSPcrpCGaT",
        "hexsec": "d38c1f602bc0bc90a54c5d743b3b75460c4aeeb1dc6ad62d3c6758c3714998a0",
        "reserve": 1,
        "sec": "5KRTGtTczAwef7vdDfm9knDyKMoaa8XHJURnMZnQFd5qkWVJtsB"

The second/fourth entries are obviously the private key.  However, if I input this key at (for instance) bitaddress.org, it generates

        1EEYqeJHkubdhcrHvH7ajpSBEALXMygoD8 (address)
        1HoVqjG35pW3AQ7wtYtA72tSpyLyP4vDLp (compressed address)

neither of which match ANY of the other addresses listed in the dump.  I can't find an explanation for this anywhere, and I'm wondering what the ramifications of losing, say, the first address in the key entry ('1NpYUP...')  or the addresses in the pool are if they don't actually correspond to the private keys in the file.

Just a heads up - do not post your private key in public unless you'll no longer be using that Bitcoin address

Thanks in advance!


texts:
Some countries view Bitcoin as a commodity, some see it as a currency (and some ban it, but that's another story).

I read a few articles, but in layman's terms, what are the main differences about a commodity and a currency?


texts: Which bitcoin client distribution to use on a secure pen drive?

texts:
I have just purchased an Ironkey. Which version of bitcoin client can run without needing installation or download of the blockchain? One which may connect to a server to access blockchain info?

So essentially I can plug it in anywhere and send money direct from the secure drive.


texts: My BTC is taking way too long to transfer

texts:
I earned 0.4 BTC from constant mining. (I use 50BTC). So I clicked payout, and sent them all to my BlockChain account. It's been "In Process" for about 1 day. What's the problem here? Does it usually take this long? Is it because they got hacked recently?

How can I get these BTC to transfer? By the way, the BTC was removed from the 50BTC account, but it's not yet in the BlockChain. Is it suppose to do this?

Thanks.

Sorry for being a noob, it's my first time with BTC.


texts: Timeout error when importing private key to bitcoinABC

texts:
When importing private key to bitcoinABC, error occurs!

error: couldn't connect to server: timeout reached (code 0)
(make sure server is running and you are connecting to the correct RPC port)

How can I solve the problem?


texts: Can Artificial Intelligence be used to mine BitCoins faster?

texts:
Can Artificial Intelligence be used to find more efficient mining algorithms?

Is there only one algorithm that can be used to mine?

EDIT: Asking about running the SHA(SHA(block header)) more efficiently to mine Bitcoin, not chainging the Bitcoin mining algorithm.


texts: Is it possible for two nodes to view blockchains differently?

texts:
Is there a chance, that at some point in time, two blocks will have different number of confirmations, according to different nodes? Like, with difference up to 3-4 confirmations?

The problem I'm having that I have Iquidus Explorer set up as my SolarCoin blockchain viewer and I have 6 as min. number of confirmations until it gets picked up and written in a database, but sometimes, transactions are written there before they show 6 or more confirms here.

Thanks in advance!


texts: How to transfer bitcoins from blockchain.info?

texts: I want to transfer bitcoins from blockchain but I don't know how. I have a bither and I want to transfer it there. How to transfer bitcoins from blockchain.info to bither?


texts: How do you delete an account in Bitcoin Core?

texts:
I am attempting to allow multiple bitcoin addresses to be created per account, but how can I delete them using the standard API? There doesn't seem to be a function for that.

E.g. the acccount "Test" :

Array (
[0] => 1JQQXBRrG5h7uW8StVtJRcGEdb4YYTqnas
[1] => 1LP8VeKDNKAgErCnYVAFvGMnrGbM3oHe6u
[2] => 1LwTx3a7hy4FZ5EJMxcPnRG9ap8AUwd2cm
[3] => 1AtbnW8dPuzp6jVnAvipiJR4o1BupCcU8D
[4] => 1K7FyNgmJ4ryjKgNz9ybxzQcYrGDEbYEUX
[5] => 1Ng77Nq1SF46MDZnz4pEirCEbbiHZ1Wthp
[6] => 175FKAiJSC9wA12BPcYZD6drTYLxXXChdZ
)

What if the user just wants to delete 1JQQXBRrG5h7uW8StVtJRcGEdb4YYTqnas?

Cheers!


texts:
New to Lightning, and I'm having a hard time understanding something about the incentive system.
So, if block sizes remain fixed, and transaction fees become prohibitively expensive one day, owing to future btc popularity, won’t there be an incentive to cheat in channels, knowing that the cost to settle on chain is prohibitive?

Who’s going to broadcast a refund transaction that costs (one day, e.g.) $100 in fees, just to claw back a few cents from an uncooperative channel node? Isn’t that an incentive for massive micro-cheating?

Sorry if i’m massively misunderstanding how this works. Is there a way to create a channel that guarantees any side can broadcast the refund without incurring extra costs?


texts: BitFinex API call returns 400 bad request

texts:
Trying to get authentication with BitFinex to work. Docs here: https://www.bitfinex.com/pages/api

  Say the client wants to make a request to POST

  https://api.bitfinex.com/v1/order/new

  With a payload of { "request":"/v1/order/new", "nonce": "1234", "option1": ... }

  The nonce provided must be strictly increasing.

  To authenticate a request, use the following:

payload = parameters-dictionary -> JSON encode -> base64
signature = HMAC-SHA384(payload, api-secret) as hexadecimal
send (api-key, payload, signature)

  These are encoded as HTTP headers named:
  X-BFX-APIKEY X-BFX-PAYLOAD X-BFX-SIGNATURE

Here is the c# code, which follows the above example, but generates a HTTP 400 Bad Request. Any ideas how to fix?

        long nonce = DateTime.Now.ToUnixTimestampMS(); //returns a strictly increasing timestamp based number e.g. 1402207693893

        string path = "https://api.bitfinex.com/v1/balances";
        string paramDict = "{\"request\": \"/v1/balances\",\"nonce\": \"" + nonce + "\"}"; //ie. {"request": "/v1/balances","nonce": "1402207693893"}
        string payload = Convert.ToBase64String(Encoding.UTF8.GetBytes(paramDict));

        //API Sign
        HMACSHA384 hmac = new HMACSHA384(Encoding.UTF8.GetBytes(APISECRET));           //My API SECRET
        byte[] hash = hmac.ComputeHash(Encoding.UTF8.GetBytes(payload));
        string hexHash = BitConverter.ToString(hash).Replace("-", "");

        NameValueCollection headers = new NameValueCollection();
        headers.Add("X-BFX-APIKEY", APIKEY);                                            //My API KEY
        headers.Add("X-BFX-PAYLOAD", payload);
        headers.Add("X-BFX-SIGNATURE", hexHash);

        //POST data
        try
        {
            //create post request
            HttpWebRequest request = (HttpWebRequest) HttpWebRequest.Create(path);
            request.KeepAlive = true;
            request.Method = "POST";

            //add headers
            request.Headers.Add(headers);

            //write out payload
            byte[] byteArray = System.Text.Encoding.UTF8.GetBytes(paramDict);
            request.ContentLength = byteArray.Length;
            using (var writer = request.GetRequestStream()){writer.Write(byteArray, 0, byteArray.Length);}

            //read reply
            using (var response = request.GetResponse() as System.Net.HttpWebResponse)
            {
                using (var reader = new System.IO.StreamReader(response.GetResponseStream()))
                {
                    //get reply (JSON)
                    string responseContent = reader.ReadToEnd();
                }
            }
        }
        catch (Exception e)
        {
            //always throws an exception here
            Debug.WriteLine(e.Message);
        }


texts: Without knowing private public key any one can withdraw btc from address. Is it possible?'

texts:
Actually I am using blockcypher API for creating address of btc and storing all records in my database with private and public key of individual address and assign that to particular users.
But few days before from my users address balance will become zero.Amount transfer into some other address.How is this possible?
Please help me out from this Its very risky.

Thanks in advance.


texts: I am currently working on reward halving changes for a test coin and i have added all the necessary changes but my question is how do i safely test this new halving without affecting production. I understand bitcoin has testnet but is there a way to test the altcoin halving. May be connecting two daemons with each other to create a closed network? Thank you in advance.


texts: Problem integrating Bitcoin daemon with PHP

texts:
I have installed the daemons of Bitcoin, Litecoin and Dogecoin on the same server. All three of them are up and running, but the Bitcoin daemon does not reply with anything when I run bitcoind getinfo. It may be network issues or something like that. I have installed PHP on the same server and created an index.php file in the /var/www/ folder.

Content of index.php file:

<?php
    include_once('Bitcoin.php');
    include_once('jsonRPCClient.php');
    $dogecoin = new jsonRPCClient('http://user:pass@localhost:8332/');
    print_r($dogecoin->getinfo());
?>

Content of Bitcoin.php:

<?php
    class Bitcoin (
        // @var string
        private $username;
        // @var string
        private @password;
        // @var string
        private $url;
        // @var string
        private $id;

        public function __construct($url,$username,$password)
        {
            $this->url=$url;
            $this->username = $username;
            $this->password = $password;
            $this->id = 1;
        }

        public function __call($method,$params)
        {
            $params = array_values($params);

            $request = json_encode(array(
                                       'method' =>strtolower($method),
                                       'params' => $params,
                                       'id' => $this-> id));
            $curl = curl_init();
            curl_setopt($curl,CURLOPT_RETURNTRANSFER, 1);
            curl_setopt($curl, CURLOPT_HTTPHEADER, Array("Content type:application/json"));
            curl_setopt($curl, CURLOPT_URL, $this->url);
            curl_setopt($curl, CURLOPT_USERPWD, $this->username.":".$this->password);
            curl_setopt($curl, CURLOPT_POST, TRUE);
            curl_setopt($curl, CURLOPT_POSTFIELDS, $request);
            $response = curl_exec($curl);
            curl_close($curl);

            if(!$resposne)
            {
                throw new Exception('Unable to connect to '.$this->url, 0);
            }
            $response = json_decode($response,true);
        }

        Then there are a condition to throw a different error upon a different situation.

    }


texts: Mempool filled with 14KB transactions, tons of inputs, 0.15 mBTC fee

texts:
With the blockchain experiencing extremely high transaction volumes (most blocks at the 1MB size limit), I am interested in studying the "backlog" of transactions in the memory pool on my own full node. In order to make such an analysis meaningful, I want only "honest" transactions in my mempool (loosely defined as: transactions that should be mined someday).

I've tried adjusting minrelaytxfee to 0.0001, but I find that TONS of "unqualified" transactions build up in my mempool. Here is a representative transaction:
effec9299f18314a7a13e525a7bdbaa9316be9d9cac9d082078ae325fff30500

That transaction is 14,799 bytes (100+ infinitesimal inputs) with a fee of 0.15 mBTC. At the risk of stating the obvious, that transaction should NOT pass a minrelaytxfee of 0.1 mBTC/KB. My mempool collects ~1000 transaction per day that are VERY similar to the one cited above.

Also at the risk of stating the obvious, these transactions are NEVER mined.

QUESTION #1: how do these transactions "fool" the minrelaytxfee test?

QUESTION #2: is there a better mechanism for filtering out such transactions?

QUESTION #4: might these transactions originate on "my" SPV clients?

QUESTION #3: are these transactions SPAM or something else?

Thanks for the insight.

UPDATE ----------

For debugging purposes only, I increased minrelaytxfee to 0.0002 and re-started my Bitcoin Core full node.

Observation: on the vast majority of transactions, minrelaytxfee is applied correctly. In other words, transactions will a fee lower than 0.2 mBTC/KB are not added to my mempool.

I continue to get ~250 transactions/hour that somehow "fool" the minrelaytxfee filter. Here are three representative transactions:

c299d3bd4e79590bf5d5b9cfb1f3db4378ffc5e9e64752f6deb8134d43f54501

ffc1ad32c1d8ca496fa52e5451c6abe56003029819029de9a0f941611f942402

65871d2e0bc438d5019e606daba59d7af1a2ce3eb079e5f0e6c9e21ef8373402

All of these "foolish" transactions follow a specific template:

Size is between 14790 and 14810 bytes
Roughly 100 transaction inputs, all of exactly 0.1 mBTC
Transaction fee is always exactly 0.15 mBTC

QUESTION: how are these transactions fooling the minrelaytxfee filter?

Tracing a large sample of the 0.1 mBTC transaction inputs, they are always produced by a transaction that follows its own specific template:

A single transaction input
Roughly 100 transaction outputs, all but one of exactly 0.1 mBTC

QUESTION: Am I correct in suggesting that this pattern appears suspicious and deliberate?


texts: How to import a private key to an encrypted wallet (on standard client)

texts:
I have a standard client (QT client on OSX) with an encrypted wallet. I've tried to import keys with pywallet, but while it claimed to be importing them, when I ran again the bitcoin client, it said wallet.dat was corrupted (yes the client wasn't running when I did the import).

I guess pywallet doesn't know about encryption and didn't care enough to check everything was ok before importing them.

So, how do I do this import?

Trying to run the command line client gets me the following error a few seconds after starting it (with -daemon option of course):

EXCEPTION: NSt8ios_base7failureE
CDataStream::read() : end of data
bitcoin in AppInit()

Running the QT client with the -server option crashes too after a while (apparently it works correctly without that).


texts:
Im trying to utilize Kraken's API.
I'm looking for a list of supported asset_pair.

Example: query_public('Ticker', {'pair': 'XETHZEUR'}) will return ticker info for ethereum in relation to euros. The asset pair in this example is XETHZEUR.

Does anyone have access to such a list?


texts: Why search for a nonce linearly (+1) vs searching only even or odd nonces?

texts:
As a solo miner, you have the disadvantage of a minuscule hash rate compared to mining pools. Is it not possible to searching for only even nonces? Of course you risk the chance of missing the nonce, but you gain an effective 2x hash rate.

I wonder how this or other nonce searching methods might impacts your chance on average.

What if you search downwards for a nonce?
Skipping (even, odd, every third, etc).


texts: Can I get the wallet in bitcoind to use P2SH segwit (on testnet)?

texts:
Can I use the wallet functionality in bitcoin cli daemon with P2SH segwit on testnet/regtest? Meaning, can I receive on these addresses and send from them?

And if I can, how?

I cannot find it anywhere in the help. The only one that gets close is addwitnessaddress, but that does something else, too.


texts:
I'm not entirely sure how FPGA's work...

Do I simply buy a ZTEX and it mines, or do I need to plug it into a computer via USB?

Can I chain them?

I'm so confused.


texts: How does Blockchain as a Service (BaaS) work?

texts:
I've been so entrenched in the world of cryptocurrencies that I'm confounded by how a Blockchain as a Service would work in the enterprise realm.

Both Microsoft and IBM have BaaS offerings, advertising that it will change the way your business functions.

I'd like to know, in general, how a blockchain system is run in the enterprise. Several questions come to mind:

Who runs the nodes?
How many miners are required? I'm assuming the hashpower your own enterprise systems could provide would not be substantial enough to have impenetrable security.
Who provides the hashpower? The BaaS provider, or your own network of computers?
Since you are the owner of this blockchain, how is this more secure than just a regular (encrypted) database with strict access control?
What is the format of the data stored in these blockchains? Are they able to insert any custom data format and payload in each transaction, since it is a proprietary blockchain?
Besides security in the form of immutability, what other benefits does a blockchain in the enterprise provide?


texts: How does bitcoin prevent someone from sending more money than he/she has?

texts:
I am new to bitcoin, I was wondering how bitcoin implements this particular functionality efficiently. Does it check through all blockchain records for the address of the sender. Or does each transaction store a list of previous transactions by the sender?

I am curious as to how this can be implemented efficiently?


texts: The ratio between propagation delay and block interval

texts:
Is there a certain website or a study that gives an estimation for the
ratio f = Propagation Delay/Block Interval for the Bitcoin network ?
I know the Block Interval is roughly 10 minutes however, I don't know the propagation delay. I define it as the time it takes for all nodes to hear  about a mined block after it's been broadcast.


texts: I have 2 transactions on electrum wallet still not confirmed

texts:
for 7 days now i have had 2 electrum transactions still not send next to both of them it says low fee is there any solution to make them send or cancel my transactions

Transaction ID 2: 7322490976f276b78c746d3208136d71fdfd35144170a591d63db3c68a8e93b4

Transaction ID 1:b48cdb255f29c6c2d7dfa0cc77f62be6dfb5e3443f910e0d9aa376010cd7486f


texts: Scrypt (Litecoin) memory / performance tradeoff

texts:
For Litecoin, if memory size is increased in processing the Scrypt algorithm, for example to 384 kB instead of 128 kB (and assuming likewise an L2 cache size of 384 kB), would the typical CPU architecture (x86, PPC, etc) be likely to see a corresponding increase in performance?  And if increased memory size were used, would mining output remain 100% compatible with Litecoin (I believe the answer is yes, but also I note that almost all GPU miners are using fixed Scrypt parameters for N, r, and p).

I realize that increasing BlockMix memory sizee is not typically done on GPU architectures, for various reasons.  Also as a note my objective is not profitable Litecoin x86 CPU mining -- I just want to be sure I understand the  memory/performance tradeoff.


texts: Is there a bitcoin explorer that can visualize where the coins are flowing from one address into another?

texts: I remember playing with a bitcoin explorer tool awhile back where one can input a bitcoin address and see all the coins flowing into it in a tree like structure. I want to be able to investigate where the coins are flowing from and to. What is this tool?


texts:
I setup a Bitcoin many years ago. I dont remember if I bought anything.
I found on my old computer a folder : Bitcoin under Appdata/Roaming ...and these files and Folders:
 BLocks
 Chainstate
.Lock
dblog
debug.log
peers.dat
wallet.dat

Was those files installed my a program of some sort ?
How can I get Access to those files to see if there are some coins in there at all ?:)
Or can I just delete all of those files ?

-


texts: How do I find the public key of a bitcoin address?

texts: I want to know the public key of my bitcoin address, (e.g. 13mtYzgprJuLUWw1EVWSPPuC88q7fGuSX1), how do I do that?


texts:
I was trying to figure out how exactly the Blockchain gap limit works. I've read the following question on Bitcoin Beta: How to solve Blockchain 20 address gap-limit problem? and started thinking. Maybe I am not getting this right, but in the answer to that question, it says, that the Blockchain will always look ahead 2-22 addresses, to see if any payment came inside, starting from the index of the address, that received payment last.

Am I correct in stating, that, if for example, 2 users try to send me a payment of XBT.

User 1, asks to deposit some XBT to me, gets an address from my site, with index 1. Then, a minute later, user 2 does the same, and gets an address with index 2. If in this case, user 2 makes the payment faster then user 1, the Blockchain won't see the payment from user 1, because from this onward, only addresses with index 2-24 will be checked?

If this is the case, this seems like a serious issue to me, maybe I am understanding something incorrectly, can anyone clear this up to me?


texts: What are the arguments for and against the increase of the block size limit?

texts: Can someone give a quick point by point list, what arguments the proponents and opponents of increased blocksize have for their case?


texts: Any studies on minimum USD value needed on BTC to make mining worth the cost?

texts:
My understanding of the Bitcoin ecosystem is that the task referred to as "mining" is actually the processing (confirming) of the Bitcoin transactions, and that the miner "finds" a coin when they find the accepted hash of a block of transactions.

Based on the information in other questions here, the mathematical difficulty of processing the transactions is expected to increase as more Bitcoins enter the ecosystem while at the same time the block reward is expected to halve at every 210,000 blocks.

The mathematical difficulty present in the mining process has of course a bearing on the cost of electricity and processing time of the hardware. On top of that the miners do have costs for paying for the warehouse or other location where the server farms are kept, besides indirect costs in things like depreciation of the hardware.

Currently we also have the situation that the USD value of BTC has been going down.

With this in mind I wanted to ask if there are any studies about the minimum USD value that Bitcoin should have in order to make mining profitable?


texts: Can I send message inside the transactions script?

texts:
I would like to send transactions with messages as described in the wiki. In Transaction with slightly changed script is never relayed, someone answered that non-standard transactions are not relaid by the client. I was wondering if this will affect this type of transactions.

Also, I would like to know if there is a source code that implement this functionality. I need to send small data (SHA256) as a digital signature that can be view by all the peers in the network and is associated to this specific transaction.

Thank you very much and your help is very appreciated


texts: How to check if an address is valid in Bitcoin Cash?

texts:
A lot of users seem to be mistakenly sending Bitcoin Cash to Bitcoin addresses and vice versa. I understand Bitcoin Cash doesn't support SegWit and that if Bitcoin Cash is sent to a SegWit Bitcoin address then the Bitcoin Cash is not currently recoverable.

How can I check if a particular address is valid on Bitcoin Cash?


texts:
I just updated my node to the lastest version 0.12, it launched and synced up fine.  Afterwards I closed the core GUI and launched bitcoind through the command line bitcoind -server and it returned with "Access is denied" and the bitcoind program was deleted from bitcoin/daemon dir.
I check the error log and it shows the following:

tor: thread interrupt
opencon thread intrrupt
scheduler thread interrupt
torcontrol thread exit
addcon thread interrupt
msghand thread interrupt
net thread interrupt
Shutdown: In progress...
StopNode()
Shutdown: done

I'm not running Tor. Any ideas what change could have prompted this new error from the update?


texts: Can I use uncompressed public keys in Bitcoin Cash transactions?

texts:
It have read that Bitcoin Cash uses BIP 143 to generate the signatures and that BIP 143 does not accept uncompressed public keys. Does that mean that you cannot send a Bitcoin Cash transaction using an uncompressed public key?

  As a default policy, only compressed public keys are accepted in P2WPKH and P2WSH. Each public key passed to a sigop inside version 0 witness program must be a compressed key: the first byte MUST be either 0x02 or 0x03, and the size MUST be 33 bytes. Transactions that break this rule will not be relayed or mined by default.
  Since this policy is preparation for a future softfork proposal, to avoid potential future funds loss, users MUST NOT use uncompressed keys in version 0 witness programs.
  BIP 143


texts: Help With Gitian-Builder - Failed to load "rcfile"

texts:
I' having hard time building the Bitcoin using gitian-builder. I'm getting closer but i'm stuck at this error and I dont know what it really means or why is it even there. I'm using the gitian-build.sh.. I posted a screen shot...

It says Failed to Load rcfile... How do I fix this issue?

Thanks!

]2


texts: Which wallets support spending partial amounts of btc from a cold storage address?

texts: Which wallets let you spend partial amounts from your btc address from a cold storage address without the need to import / sweeping it? I know mycellium has the feature, but I'd like to know if there are others that can do this.


texts: What is the tax regulation for Bitcoin in India? If I make profit out of Bitcoin, what percentage will I have to pay to the government?


texts: BITCOIN: get bitcoin transactions list by time using RPC on my node

texts:
I want to get the transaction list of a bitcoin node i have. I need to know:

How do i get the transaction list filtered by time (1h, 2h,...) using RPC, I have been searching on bitcoin developer: RPC API reference  but i can't find a method that allows me to get the transaction list by time, there's only transactionlist method by quantity (number of transactions i want to).

How do i get a notification when a new transaction has been made, i've known already walletnotify where i specify a restAPI I created (my/custom/route) using curl from my node, and I recieve the txId anytime the node receive some change. The thing is, I need to store/queue those notifications whenever the restAPI i created got disconnected, if that service comes back/is restored the node needs to send those notifictions to my API.


texts: Can I pass values over a bitcoin bip 70 URI?

texts:
is it possible to add arguments such as BTC amount to a bip 70 URI, something like:

bitcoin:?r=http://127.0.0.1:8000/paymentobject/?amount=10

I already tried with the backwards compatible URI:

bitcoin:?amount=10&r=http://127.0.0.1:8000/paymentobject/

But the client doesnt seem to register anything other than the 'r=' param.

Any help greatly appreciated :)

EDIT:
Added function from django views.py for extra explenation-

def protoresponse(request):
    xpo = payments_pb2.ParseFromString(request)

    returnaddress = xpo.Payment.refund_to
    transactions = xpo.transactions
    memo = xpo.Payment.memo

    xpa = payments_pb2.PaymentACK
    xpa.payment = xpo.SerializeToString()
    xpa.memo = u'success, i think'
    return HttpResponse(xpa.SerializeToString(), content_type="application/octet-stream")

Note, the function is defined as protoresponse because we have optional string payment_url = 6; in the payments.proto file.


texts: How does one get money into the Ripple system? There appear to be ways how one can lend various currencies in the system, but how does one get non-debt money into Ripple?


texts: Why MtGox does not accept a bank statement as proof of address for verification?

texts:
To increase the transaction limits on a MtGox account you need to submit a personal ID (passport or drivers license) and a utility bill (electricity/water/gas/phone) as a proof of address. It is explicitly  stated that a bank statement will not be accepted.

That makes it next to impossible for many people to use MtGox, because they do not have utility bills in their name (for example they live with friends or family, and the utility bill is in the name of the owner or official tenant). Also students living in dorms will not have utility bills. I think that more then half of the worlds population does not have utility bills in their name - usually several people live together in one building/flat, and the bills are only in the name of one of them, who is responsible for paying. It may not be possible just to change the name of the person on the bill, because of contract, liability, creditworthiness or many other reasons.

They also seem to accept a "residency certificate" instead of a utility bill, but also excludes many people, but that also excludes many people, as they can not and need not obtain such certificate, as their citizenship and/or passport alone allows them to stay in the country, either indefinitely (in their country of citizenship) or for a limited time (in other countries).

Why does MtGox not accept bank statements, which is an accepted form of verification for most, if not all other financial services, for example:

Moneybookers
Currencyfair
Neteller

All these services, and a countless number of others, accept a passport + bank statement for full account verification. That is a commonly accepted and fully sufficient for AML.


texts: Blockchain.info's blockcount API call giving error, alternatives?

texts:
This URL today: https://blockchain.info/q/getblockcount

Was giving the error "Too many requests".

Any alternative out there to get the blockcount via an API? Thanks


texts:
The bug is with https://bitcoinchain.com

Before I report it I would like to see if I can gain any additional clues as to what might be going on in order to assist their developers to get to the root of the problem quickly.

If I call their API like so:

https://api-r.bitcoinchain.com/v1/address/utxo/1KZnzTTfuxiyHUJdLqn3UnHyTVDN2UgeHU

then add up all of the utxo.amounts they gave me for the wallet in question I get 0.57944267

But if you examine the wallet here https://blockchain.info/address/1KZnzTTfuxiyHUJdLqn3UnHyTVDN2UgeHU

you see that it really holds 1.15968995

With a little digging I see at least two of the utxos txid/hash(s) where they have incorrectly got the wrong output:

https://blockchain.info/tx/37ff697bc958071e6f6dc180f9b80edda8f87ab0ca2ad5cd3753e8f65c38e463

  they have picked the wrong wallet address 1o69bsLaqaAM6R7bomaGVFT7uvGFvziTy

and

https://blockchain.info/tx/a02d62638266fe5b9004e99a45d5eca0878ab5dae1d328aeece39672f44cc98eeece39672f44cc98e

  they have picked the wrong wallet addess 16tk4YEYpE6taGzZjkH9aiEApLLDR8UZL9

Not every utxo has this mistake, so it could be ruled out that they are always picking the first output.

I would have thought that they should just be asking if the output address matches the queried address but if they were doing that then surely this bug would not exist!

What other factors could cause this?


texts: RPC command sendfrom is giving Transaction too large error

texts:
I made discord bot for fun with tips, soak and rains of altcoin. When I try to send large amount through the same bot. It is giving me "Transaction too large" error. I found the reason here: transaction creation failed

I need help with solving this issue. Can someone help me?

Thanks in advance


texts: How to see the number of segwit transactions in a block

texts:
Now that segwit is active I am interested to know how many segwit transactions are in each block.

The Blockchain explorers I've looked at don't seem to be tracking this info.

Is there any service that would allow me to view the number of segwit transactions which are in each block.


texts: Profitability comparisons for Quarkcoin and Primecoin?

texts:
I've found sites where you can put your hash rate for scrypt and SHA-256 to check which cryptocurrency would be the most profitable for you to mine, such as:

http://dustcoin.com/

http://www.coinwarz.com/cryptocurrency

I've not seen such a site include profitability comparisons for either quarkcoin or primecoin.  So my question's twofold:

Is there a site that includes either of them in the comparison of profitability?
Any reason they might not be included?

Especially after the furor caused by primecoin's launch, I find it difficult to understand this absence - whereas Dogecoin is indeed included.


texts: Is it possible to have a single input or output with multiple addresses

texts:
I've seen in more than one Blockchain API provider's specs where the transaction inputs and outputs are in the following format:

addresses: ARRAY
The address (or addresses in the case of multi-sig) to which the value was transferred.

I'm confused about the array. When I try these APIs with a transaction where one of the outputs is to a multi sig address, I still see a single multi-sig address in the output.

In which cases would I see multiple addresses in a single output or input?

This the same in these api providers:

https://chain.com/docs#object-bitcoin-transaction

http://dev.blockcypher.com/#transactions

https://toshi.io/docs/#get-transaction


texts: Is Wuala (LaCie) the largest company to accept Bitcoins?

texts: I just found out that you can pay for Wuala with Bitcoins. They are owned by LaCie, who have a revenue of €351.8 million according to Wikipedia. I think this makes them by far the largest company to accept Bitcoin for payment. Is that correct or are there other big players in the economy?


texts: Where can I find a detailed network protocol spec?

texts:
I have been trying for a while to understand how the bitcoin network works, which I (kind of) do on a high level. However, all of the sources I read don't go into the details of the protocol that nodes use in order to communicate with each other.

I'm trying to make a client that directly asks other nodes for the last few blocks in the blockchain and displays it to the user. I know this isn't nearly as secure tracing all the blocks back to the genesis block, but I'm doing this mostly for fun and education. So I don't care that much about security.

I can't find any clear specifications for the protocol. There must be something obvious I'm missing, but I don't know what it is.

Where can I start, or how do I know what should be sent to other nodes in order to request a block?

Thanks in advance.

Sorry if sound too stupid, it's just that I'm new to programming blockchain nodes and I don't know where to start...


texts:
I have an account on binance and i would like to trade on the platform in the BTC/USDT market. However something does not add up to me.

Lets say at 1100 HRS 1 BTC = 6154 USDT and at 1200 HRD 1 BTC = 6180 USDT

I should therefore be having more bitcoins if i sell when 1 BTC = 6180 USDT but this does not seem to be the case. I have attached the graphic to demonstrate what i mean.

What is exactly happening here?


texts: Bitcoin takes into account clock of nodes on the network when propagating transactions tru the mempool and persisting them into the next block. If majority of the network clocks are compromised what kind of issues would occur?


texts: What are some forks of Bitcoin that ultimately failed?

texts:
Being as many of the popular cryptos today were forked from Bitcoin at some point, I'm curious which past forks seemed promising, but ultimately failed at some point..

Sort of a history lesson if you will, so what past coins failed and why?


texts: Bitcoin deposit stuck 0 confirmations high confidence/low priority

texts:
hi i have a deposit stuck in the blockchain im not understanding why, its been stuck for 7 hours now without any confirmations, what is the explanation behind why the transaction is stuck?

https://live.blockcypher.com/btc/tx/e83922d98fc5f4a882e1ae04c3d1d56b1eee092a5e1caa2788f8a8fd5553460b/


texts: Which function in which file verifies that transactions are the right size

texts: Which file(s) are responsible for the procedure which confirms that transactions are well-formed, specifically that "Size in bytes < MAX_BLOCK_SIZE" as described in the Protocol Rules article on the wiki: https://en.bitcoin.it/wiki/Protocol_rules?


texts: In Bitcoin blockchain, Segwit takes the script, which containers the signature and sender's public key, out of each transaction and stores them into an extended block. However, why having an extended block can make the blockchain faster? Since I think each miner now has to process the original block plus the extended block, thus the amount of data each miner needs to be processed has not been changed. Please advise!


texts: mining difficulty is not changed on regtest

texts:
I want to see the automated mining difficulty change on regtest but it did not change even I generated 2016 blocks. How can I see it?

// initial difficulty
$ ./bitcoinA/src/bitcoin-cli -rpcuser=bitcoinrpc -rpcpassword=bitcoinrpcpass -rpcport=16591 -regtest getmininginfo
{
  "blocks": 0,
  "currentblockweight": 0,
  "currentblocktx": 0,
  "difficulty": 4.656542373906925e-10,
  "networkhashps": 0,
  "pooledtx": 0,
  "chain": "regtest",
  "warnings": ""
}

// generate 2016 blocks
$ ./bitcoinA/src/bitcoin-cli -rpcuser=bitcoinrpc -rpcpassword=bitcoinrpcpass -rpcport=16591 -regtest generate 2016

// show the difficulty
$ ./bitcoinA/src/bitcoin-cli -rpcuser=bitcoinrpc -rpcpassword=bitcoinrpcpass -rpcport=16591 -regtest getmininginfo
{
  "blocks": 2016,
  "currentblockweight": 4000,
  "currentblocktx": 0,
  "difficulty": 4.656542373906925e-10,
  "networkhashps": 12,
  "pooledtx": 0,
  "chain": "regtest",
  "warnings": ""
}

// generate 2016 blocks again
$ ./bitcoinA/src/bitcoin-cli -rpcuser=bitcoinrpc -rpcpassword=bitcoinrpcpass -rpcport=16591 -regtest generate 2016

// the difficulty was not changed
$ ./bitcoinA/src/bitcoin-cli -rpcuser=bitcoinrpc -rpcpassword=bitcoinrpcpass -rpcport=16591 -regtest getmininginfo
{
  "blocks": 4032,
  "currentblockweight": 4000,
  "currentblocktx": 0,
  "difficulty": 4.656542373906925e-10,
  "networkhashps": 12,
  "pooledtx": 0,
  "chain": "regtest",
  "warnings": ""
}


texts: Which method/programme can create a wallet using the least amount of space?

texts:
On a first attempt to create a wallet with bitcoind, the process failed after filling the 160 Gb available in my home disk.

Which method or programme would allow me to create a wallet using the least space possible?

Update: I removed bitcoind and am now using Electrum. However, this freed up hardly any space on disk. How can I delete whatever files bitcoind created?


texts: Lightweight Wallets Communication with Blockchain

texts: I understand how the Bitcoin core wallet communicates with the blockchain, but how do the lightweight wallets like Multibits, Electrum, etc, communicate with the blockchain?


texts: I have requested funds sent to my Electrum Wallet receiving address, but have not received over a week now. According to the Blockchain ledger the funds are shown as "Unspent", help needed


texts: Peergroup download of the blockchain stalls?

texts:
I'm using bitcoinsharp to build my client. I try to download the blockchain in a peergroup network. Download starts, but when progress is 98%, the download is stopped & the client is waiting (2 hours without any change). The size of the downloaded blockchain file is 4.5 MB.

I use the following code:

PeerGroup peerGroup = new PeerGroup(blockStore, @params, chain);
peerGroup.AddAddress(new PeerAddress(IPAddress.Parse("84.38.65.102")));
peerGroup.AddAddress(new PeerAddress(IPAddress.Parse("83.23.15.71")));
peerGroup.Start();
peerGroup.DownloadBlockChain();

Any ideas?


texts:
Let's suppose that I can create SHA256d collisions, and I use this ability to create two transactions that have the same hash, A and B. These transactions are not the same, but they hash to the same value.

I submit transaction A to the network, and wait until it has a few confirmations. Then, I submit transaction B. Will it get included into the chain? Will it overwrite transaction A?

If the answer to the previous two questions is yes, then what will happen if the block containing transaction B is reorganized out of the chain? Will transaction A be un-overwritten?


texts:
I had some BTC in my electrum wallet prior to the BTG fork - sent it there approx 7 days before it happened. I am trying on a MAC using Bluestacks emulator to run coinomi wallet - all works fine but when I try to sweep my keys into coinomi I get 'There are no funds in that private key' message.

I have found the address that def contains the funds in electrum and exported that private key into coinomi.I have tried bit address.org to try all the different key formats and all give the same message - NO FUNDS

Whats weirding me out is when I check on block explorer it puts the transaction of when I originally sent my btc to electrum in a higher block number than when the fork happened - even tho I sent it at least 7 days before the fork happened?! How can this be? Obviously that may account for the zero funds problem but the thing is the funds were def there way before the fork date - I have transaction details to prove this. Any help gratefully received ...


texts: Can a blockchain offer transparency to a humanitarian aid supply chain?

texts:
I am located in a middle eastern country which is in desperate need of humanitarian aid.

I have contacts in western countries who are willing to call upon their independent donor network to provide significant amounts of aid in the form of physical assets (not financial). However there is concern over the transparency of the supply chain on the receiving end, as it is typically the case that physical assets tend to disappear in the region, whether they pass through official channels or not.

Therefore, I am interested to know if a blockchain could be used to provide transparency to this humanitarian aid supply chain.

This would greatly increase the confidence of donors and thereby lead to greater amounts of aid being delivered where it is needed.

I have read that blockchain can be used for physical assets and can increase the transparency of a supply chain from a consumer perspective of provedance, but this is the opposite way around, where it is the supplier wanting to have transparency in regards to the beneficiaries of the physical assets.

Furthermore, if this is achievable, I would also be interested to learn how to establish such a blockchain ie what resources or technical knowledge is required or where can these be obtained.

Thank you in advance for any input.

C.


texts:
I am constructing a small online store where I would like to accept BitCoins as payment.

I have not had any luck running the Deamon on my server, so I was planning to use tradehill.com and then make use of the API.

But every time I log in i get the

  "Socket not connected Sorry, our notification socket isn't connected
  yet. Try again in a few seconds!"

Error... And it's making me kind of anxious to use the system, since it seems a bit derelict.

Does anyone know any similar systems ? Or know what's going on backstage of TradeHill.com ?

Any suggestions will be much appreciated.


texts: Is there a list of available APIs for Bitcoin exchanges?

texts:
So far I have seen some Perl modules; Finance:MtGox and Webservice:MtGox for interacting with Mt.Gox, a Ruby gem for Mt.Gox and a Python based command line client for again, Mt.Gox.

I'm wondering if there are any other language APIs for other exchanges?

I'd especially like to find a Java API for more than one exchange.


texts: Convert Electrum p2pkh wallet to p2wpkh one?

texts: Is it possible, in Electrum, to convert a p2pkh wallet to a p2wpkh one, so I can use the Lightning network?


texts: What’s prevents people from appending useless blocks to very old blocks in order to revert new transactions?

texts:
As far as my understanding goes, nodes in the network should accept the longest branch of blocks and disregard any other branches (excuse my terminology if it’s not what’s normally used - I hope it is clear what I mean).

If this is correct, I am wondering what would prevent me from creating my own node in which I append blocks to very old blocks. These appended blocks could contain transactions from my address to another one of my addresses for example (just to make sure the block is valid - I’m assuming there are some constraints on what makes a block valid, like amount of transactions or bits in a block). After probably a long while I would have a branch that has outgrown the current branch, undoing all transactions from the block my node started with to the current active block, and instead replacing all of those by my useless transactions.

What is preventing me from doing this? I know that I would still have to mine these blocks, and understand that this would probably be a the main thing preventing me from doing this right now.

However, as I understand, mining difficulty is determined by the amount of blocks mined in a certain time. Say that the BTC network becomes useless one day for some reason, and almost no new blocks were created, would it then be possible to execute this (after a long while to keep the difficulty of my own mined blocks low)

Thanks for any answers in advance. If BTC does ever become obsolete and unused it’d be cool to magically be able to erase everything (if there are still nodes around that is)


texts: how generate  part of scriptSig in bitcoin transactions

texts:
I studied many links about bitcoin trxs and about generating scriptSig.
Finally I couldn't understand how to make this part.

for example I read this links:

What is relation between scriptSig and scriptPubKey?

https://bitcoin.org/en/developer-guide#transactions

How do you create a scriptsig for a new raw tx?

How to redeem a basic Tx?

How to create the <sig> <PubK> part in "scriptSig"?

http://www.righto.com/2014/02/bitcoins-hard-way-using-raw-bitcoin.html

https://en.bitcoin.it/wiki/Protocol_documentation#tx

https://en.bitcoin.it/wiki/Transaction

I found that I must sign a thing but whats that thing ?

exactly and step by step What should I put together and then sign it?

specially if I had more than 1 input how make sigscript ?

I have a library that does the sign operation for me. however, I don't know what structure I need to use for the message that is going to be signed especially when there are multiple outputs.


texts: Accesing bitcoind through terminal on mac

texts:
How do I use bitcoind through Terminal on Mac OSX? I think this is not adressed by these questions, but honestly, I'm not sure:

Bitcoin-Qt command line control on Mac

What are the steps in building bitcoind on Mac OS X 10.6?


texts: How do blockchains in each nodes maintain consistency?

texts:
What I understand as (Please correct me if any statement is wrong)

Every full node tries to generate a new block, in which different amount of transactions are included and what to be included will not be identical. This results in unidentical UTXO set and mempool for every full nodes.

If above statement is true, then is it okay to understand as that when the blockchain is replaced(because a new block was introduced by other node, or the blockchain branch I have became stale anymore), then the UTXO set and mempool I maintained is replaced subsequently?

If it is not the case, then how can a node resume mining after the new block is introduced? A UTXO which is known to be unspent beforehand can turn out to be spent after a new block is introduced.


texts: cloning bitcoin how bitcoin find new nodes

texts:
I am studying blockchain, cpp and crypto so I cloned bitcoin and created a new altcoin.

everything it is working fine as I expected, but i have some questions which i could not find a answer.

the question it is about nodes,let me explain my case.

I have now 3 VM's running the bitcoin clone wallets which it is a new coin now.

vm 1 = it is connected to the node 100.00.00.0

coinname.conf

addnode=100.00.00.0

vm 2 = it is the server which provide the ip: 100.00.00.0 for the vm 1

vm 3 = random wallet as well connected to the ip 100.00.00.0 for the vm2.

coinname.conf

addnode=100.00.00.0

I removed the nodes and dns from net.cpp for do this experiment ok?

strMainNetDNSSeed[][2]

pnSeed[]

so I started do experiment, turning of the VM 2 which provides the ip for the wallets connect.

after this the VM1 and VM3 lost the connection, fine I expected that.

so my question is, how the wallet VM 1 and VM 3 will connect by themselves and keep the networking running if the VM 2 if the server it is offline? and as well if the 2 users don't know the ip it is sharing the nodes?

I searched this topics bellow but i could not find what I am looking for.

How does bitcoin find peers?

How do bitcoin nodes initially find peers?

https://en.bitcoin.it/wiki/Satoshi_Client_Node_Discovery

EDIT:
the user bellow was right, after while the other wallets get the peers and nodes , so does not matter anymore if the VM2 it is offline, the network keeps on, amazing thing about bitcoin. :)


texts: Is something gained by double spending myself on a 51% attack?

texts:
I try to understand what consequences double spending may have.

Let's assume I own 51% of the network and own three bitcoins wallets. If I double spend the coins from Wallet A to B and C - would I have doubled my coins?

I know that they are not really doubled, but if no one would noticed, would I be able to e.g. send them to Coinbase wallet and convert the double amount to USD?

If not, how does an attacker actually make money from a double spending?


texts: Is there a reason why miners should respect the default maximum block size?

texts:
Actually the default maximum block size is 300,000 Bytes and the protocol hard limit is 1MB.

So what I understood is that all blocks over 1MB will be rejected but the ones between 300,000 Bytes and 1MB will not.

So if there are lot of transactions with little fees that make that a miner can create let's say a 700,000 Bytes bloc. Will it be profitable for the miner to create such a block or is there a additional risk that his block will be rejected?


texts: I was informed by the company who sold me my bitcoins machine that I could convert my bitcoins to cash by using a mastercard so that I could make purchases or pay other bills using that mastercard, is this true and how do I do this?  If not, what is the best method to convert bitcoins to cash?


texts: Ardor configuration settings to connect to remote node without downloading entire blockchain locally

texts: What configuration is required to run the Ardor wallet software without downloading the entire blockchain, but only connect to a remote node?


texts: How may i get all transaction from A address to B address & opposite?

texts: So i just finish download the blockchain from Bitcoin Core, how may i load them files, filter all the transaction from an address to another & print it to text file with detail?


texts: Can I change current receiving address in Bitcoin Wallet app?

texts: I download Bitcoin Wallet app. I receive BTC on first address (old type), but after some time second address (bech-32) became "this is you current address for receiving". Can I change receiving on first address?


texts: How to recover Bitcoin Cash from Multibit Wallet?

texts: I have been reading through posts and cannot figure out if this is possible or not. But I had bitcoin on an old Multibit wallet. I do not have the seed phrase from when I opened the wallet, just the key to the wallet. I have just moved the bitcoin off to a secure wallet. However is there any way to recover the bitcoin cash? Thanks in advance!


texts: How can a user or wallet have multiple addresses at all if out of a private key can be generated only a single public key?

texts:
A user of a wallet, regardelss of a version of a wallet, can generate as many addresses as he wants, right?
Since an address is basically a public key, and in "private-public key" cryptograpthy there's only one public key that corresponds to a private key, how is generating lots of addresses possible at all?
This Can same private key generate multiple addresses? isn't what I'm asking about.


texts: How would an Auditor ("m") of BIP32 audit the keys generated by the master?

texts:
Suppose an auditor needs to review all the incoming Tx for a given wallet... or many wallets.  What are the logical steps the Auditor needs to do?

Do they need to pre-generate a list of all possible public keys and watch new blocks for those transactions?

Assuming that there is no limit to BIP32 keys, that means the auditor would need an infinite amount of resources to audit a key (pre generation, and then cross referencing each incoming Tx).  What are some appropriate ways to constrain this auditing?


texts: Can High CPU Droplets from Digital Ocean be used for Bitcoin Mining?

texts:
Can the High CPU Droplets from Digital Ocean be used for Bitcoin Mining? Can they compete with GPUs?

Digital Ocean High CPU Droplets


texts: What's going on with address 1NZ9kxxUykiNSe61ZRNPLqWeVHVRnirGry?

texts:
Does anyone know what is going on here:

https://blockchain.info/address/1NZ9kxxUykiNSe61ZRNPLqWeVHVRnirGry

As far as I can tell, it looks like the "1NZ9..." address seems to be one one of those which "cannot be decoded"? How did blockchain.info then decide to show this information page on the address? Because, If I do a getrawtransaction on the tx shown there, I get no addresses from bitcoind.

And if the address is one of the "cannot be decoded" ones, how come the Total Received and Final Balance fields are 0?


texts: Can there be stale blocks in "header first" implementation?

texts:
The Bitcoin developer guide mentions stale blocks as not being in the longest chain, then moves on to orphan blocks. It states you don't get orphan blocks, "and if you do" they are just dropped. But it doesn't mention whether stale blocks are also "abandoned" (for lack of a better term).

p.s. I'm thinking of using a blockchain for scores in my game, to have a universal top ten sort of thing. Any comments welcome.


texts: Bitcoin transaction fees and how to handle it

texts:
Lets say I set a very low transaction fee for a bitcoin transaction(from one of my own wallets to another). I also have mining equipment which is mining for bitcoins. Is there anyway to get that transaction request directed towards me ? In other words can I process my own transactions by giving it priority?
If so how do I do this?


texts:
What will be the script like for a situation like this:

Lets say Alice and Bob are 2 parties. Alice has a password which Bob wants. Alice will only give Bob the password if Bob pays 5BTC to Alice. How can we ensure Alice can consume the money only if she gives the right password to Bob. Else Bob gets the money back.

I was thinking along the lines of Bip199. Please let me know if anything else can be done as BIP199 faces a flaw. I was recommended to use OTP but how to incorporate that in a Locking Script.


texts: What is the meaning of "service bits" in Bitcoin?

texts:
// Note that of those which support the service bits prefix, most only support a subset of
// possible options.
// This is fine at runtime as we'll fall back to using them as a oneshot if they don't support the
// service bits we want, but we should get them updated to support all service bits wanted by any
// release ASAP to avoid it where possible.

Reference: https://github.com/bitcoin/bitcoin/blob/master/src/chainparams.cpp#L116


texts: How does mnemonic recover a single private key?

texts:
As I understand the algorithm of mnemonic (BIP39) can generate billions of private keys from your 14-24 words.

Whats the mechanism that some wallets/clients use to recover a single private key, my private key?


texts: How could a large owner of Bitcoin give back to the Bitcoin community in an equal way?

texts: If there was one large owner of Bitcoin, for example somebody who owned 3% of all mined Bitcoins, would there be a way for that person to give back their Bitcoins in an equal way? I'm thinking more along the lines of equally giving their money away to other Bitcoin holders based on how much money they had invested in the currency, not really along the lines of using their wealth to lobby companies to accept Bitcoin.


texts:
Can I send my crytocurrency in coinpot bitcoincore bitcoincash, mooncash, ect to my coinbase wallet?
How is this done?


texts:
Please teach me why I should mine bitcoins, aswell as how please so I can learn.

Please, I really want to mine!


texts: Is it possible to transfer Bitcoin from one wallet to another wallet?

texts:
For example, if I buy bitcoin from Blockchain, can I transfer it to Coinbase?

And will there be a transfer fee involved or is it free?

Thanks :)


texts: What does "prev_out" and "n" mean in blockchain.info's API data?

texts:
When getting information about transactions with blockchain.info's API, every transaction contains exactly one "prev_out" object, and within that object "n" is always equal to either 0 or 1.

What do these things stand for/mean?


texts: I don't have a wireless printer so I'm thinking about writing down the keys by hand on pieces of paper. Obviously I can't copy the QR codes that way. Are they necessary or do they just exist just for our convenience?


texts: How would you find the Merkle Root with a Block that contains 6 transactions?

texts:
Let's use block #100205
https://www.blockchain.com/en/btc/block/0000000000033d0de6f4ebe93b3b142424cdbecf4bd98b948e856c4a55f09f76

This block contains 6 transactions. After the second level of hashing you end up with 3 nodes. What is the fix for this? Do you create two 5's and 6's?


texts: Could Hadoop be used as a mining pool architecture?

texts:
The context is here

I don't know how exactly the new blockchain candidate was calculated in Bitcoin Network, so I guess it was based on a Merkle candidate of (a) bitcoin client/s. Also I presume that is by referring the diff of network, a client hashing the/a (golden) nonce, and then propagate it to the network, if lucky enough other nodes think this nonce is ok (the first), somewhere magic happened you get the coin (please enlighten me about this magic).

Please correct my understanding.

So (if you know Hadoop)

Despite how actually SHA(Midstate(nonce++)) was implemented in a Reduce procedure (hashing/sec/energy), how could I generate new Merkle tree(s) and midstate candidate(s) in Hadoop way (huge number of them simultaneously)?

Thank you for your reading (hard to understand).

Problem (if prior has no big problem)

What I am proposing here is, if all this works, how could a mining pool like this benefit from Hadoop? (if it could)

(If it really works, I'd implement raspberry pi to hook up hundreds of SHA asis of my own in distributed fashion.)


texts: Is there any Bitcoin Exchange that doesn't have fees for euro SEPA deposits/withdrawals?

texts:
Since Tradehill disappeared, which was really sad, I cannot find any Bitcoin exchange that let's me deposit and withdraw euros without fees, while they do for US dollars.
Both Mt.Gox and Intersango have a 10-20 PLN fee that their bank charge. While Bitstamp has a 0.90 EUR fee + a EUR-USD conversion rate.
Note that I'm looking for a real exchange, not for a person-to-person service like Bitmarket.eu or Bitcoin.de.


texts: Trying to understand why hash value is more secure from hash algorithm

texts:
I am currently studying in college in the US and was actually curious about bitcoin and cryptocurrencies as a whole. I started looking on free university sites like Stanford university and New York University and even attempted to do questions of their past papers. I answered most of the questions, but I am stuck on one of the questions:

Suppose your professor wants to award each student in the class a random priority for office hours help by giving them a number H(studentID||Bi)
where Bi is the ith block header in the Bitcoin blockchain.Would the scheme be me more secure if you instead used H(studentID||Bi-1|| Bi)? (https://cs.nyu.edu/courses/fall17/CSCI-GA.3033-019/assignments/practice_final.pdf)

I get that it maybe more secure if you use the Bi-1 because you have more inputs to generate an output, but I feel like that is not the reason.


texts: Will "Taproot" replace Lightning Network?

texts:
Can somebody explain to me if Taproot will fix the issues that Lightning Network solves, without the Lightning Network?
That is, near-zero fees, privacy and fast settlements?
Will Taproot allow me to skip Lightning Network and simply use pure Bitcoin Core?


texts:
I've written some code for connecting to the network, receiving inventories, and requesting data. What I am noticing is that my local node never sends me inventory messages with blocks in them unless I specifically request blocks.

So if I do a getblocks call with a zero stop hash I will get all of the blocks up to the tip, but never any inventory messages after that. Is there some kind of signalling necessary to tell the node i am connected to that I want inventory block messages to stream to me when new blocks are found?

I am connecting with protocol version 70002, relaybool is 1, nodeservices is 1.

I don't see other mentions of this issue so I'm wondering if there is a negotiation issue that isn't being caught or some other problem.

There is no visible ban score, connection is from localhost, I get a verack and normal tx inventory messages are streamed. This happens regardless of whether -whitelist is used. I just never get block inventory updates or unsolicited block messages unless I request blocks via getblocks. After I've retreived blocks up until tip streaming does not commence.

Update: The code has no problem syncing with a bitcoin-core instance on another computer, but the local bitcoin core instance will never send block inventories or respond to getheaders requests. Problem only occurs on localhost to localhost initated connections.


texts:
My BTC wallet was bitcoin core ver. 0.12.1

After sending my BTC to another address, and waiting for two days status was 0 confirmation, maybe be because the transaction fee was not enough,

So I found a solution from google, -salvagewallet, then it seemed to work

But today I try to send my BTC again, after I insert my pass-phrase, a window show up which says

assertion failed program:C:\........bitcore-qt.exe file:wallet/crypter.cpp,line 190 expression: false

if click ignore button, it says pass-phrase incorrect.

if click retry,  it says runtime error.

don't know how to solve this problem


texts: Proving collisions on Bitcoin addresses without discovery of the private key?

texts:
If there is a private key that leads to a collision on an address, it is possible to show that the private key is not the one used previously, even though they have a collision on the address?

Specifically, if there was a collision on one of the Satoshi-owned early blocks, could it be challenged, to show that the person who got it didn't have the initial private key? Specifically, if they signed the same script that was used originally, wouldn't it generate a different signature, while the original owner would be able to reproduce the original signature?

Thanks,
David


texts: Whether coldcoinbitcoin.com or some other, possible to save our private key?

texts:
I don't have wallet yet, so I do googling about it, and found that cold wallet is more secure than hot wallet, one of example of cold wallet I found is coldcoinbitcoin.com

And I think about how they can print our private keys, if they can print our private keys that means, they are possible to save them? is not that can be dangerous for our assets?


texts: Witness data storage localisation in the blockchain

texts: Since segregated witness is in place inside Bitcoin blockchain, my understanding is that witness data are no longer stored inside the blocks, so if blocks are linked to each other where theirs corresponding witness data are stored ? There is a parallel block chain ?


texts: How can I determine how much "gains" I've had from Bitcoin?

texts:
I bought a bunch of BTC in early 2013. Since then, I've bought very small parts of Bitcoin every now and then up until now, for much larger (and increasing) price.
Many of those "original" coins have been lost. While there was a "hard fork gold rush", I gained some more from the ones I already had by claiming "Bitcoin Gold" and "Bitcoin Diamond" and all kinds of such things and then trading them back to real Bitcoin using various non-KYC/AML webpages which allowed me to do this without registering any account. I can't even remember the name of those services, let alone the exact details of when I did it or how much I got.
I have no idea whether the coins I have left today are all from those original coins, which I bought for next to nothing, or if some of them are part of the ones I bought in later years, at a much steeper price. I have no idea how I'd even figure that out.
With such a messy situation, how can I possibly calculate how much taxes I owe to the government if I were to sell/spend my coins? I seriously don't understand how I can possibly determine how much "gains" I've had considering the messiness of it all.
With this in mind, what am I supposed to do? Assume that all the coins I have left are part of my first batch of coins, even though this will mean that I have to pay taxes on basically the full balance? And even if I go that route, I can't prove how much I paid or when. (It was Localbitcoins pre-KYC/AML.)
I don't understand how I'm supposed to figure this out, and the government's website is (of course) to no help. What would be the most reasonable thing to do? Just "bite the bullet" and pretend that I got all the coins I currently have for free, and thus have to pay taxes on the entire balance?


texts: Which approach is better to interract with Bitcoin node : Rpc call or Library?

texts:
I think library like BitcoinJ or python-bitcoin does the same (rpc call in the background). If that is true is there any reason behind using such  libries in place of rpc call
For example:

(in case of python)

rpccall:

import requests
payload = {"jsonrpc":1,"id":"curltext","method":"getblockchaininfo","params"=[]}
response = requests.get(url,  data=json.dumps(payload))

Library call:

import bitcoinrpc
conn = bitcoinrpc.connect_to_local()
info = conn.getblockchaininfo()

Why should i choose one approach over the other when they are working the same way? What is the diffrence in between them? And which approach executes faster?


texts: Found an old wallet with transaction history with coins (unconfirmed), but no balance

texts: I have found an old bitcoin wallet in my files. I can see there are old transactions but they aren't confirmed. But there should be more BTC received than was sent, so there should be a balance. Is there anyway to get those transactions confirmed from 2013. And how do I check those addresses to see if there is any balance in those wallets?


texts:
Is it possible to restrict all connections to an IPV6 address?
I've set
onlynet=ipv6
bind=::

But it seems that nodes are still attempting to connect to an IPV4 address (in addition to the IPV6 address).  Is there any way to prevent this?  I am seeing discover and addlocal both being set to the IPV6 address on startup.
Thanks!


texts: How to create walletconflicts in regtest mode?

texts:
I play with Bitcoin Core 0.13 in regtest mode using python. Now I use bitcoin-testnet-box, I have two nodes connected to each other. I want to create a walletconflict. I want to get gettransaction <txid> result with non-empty walletconflicts field.

How can I achiev this?

I've tried to get two different addresses from one node and send money to them from another, using raw transactions api and -zapwallettxes restart, but the second txid is not visible in the recipient wallet.


texts: How many addresses does bitcoind use for Bitcoin generation?

texts: When bitcoind is generating Bitcoins, does it change the addresses that are used for receiving the block reward? That is, if I mine two blocks with the same bitcoind wallet.dat, will the same address be credited with both of the rewards?


texts: Is cgminer used for both bitcoin and litecoin GPU mining?

texts:
I'm trying to figure out which software to download for my Ubuntu 12.04 box to start some litecoin mining.  Via google search, I keep coming up with cgminer for both bitcoin and litecoin mining.

How does that work, is the same software cgminer used for both bitcoin and litecoin mining?


texts: How Do HD Wallets Keep Track of all accounts?

texts:
If a HD Wallet generates 1,000 accounts for example.

How would they keep track of all of the account's balances, if someone for example, paid into the 455th account, they would want to update the wallet balance.

I imagine that storing all of the accounts would not be efficient, and querying the blockchain or an API for all 1,000 would not be efficient either.

Using an isolated use case:

If an API HD wallet generates 1,000 addresses, it cannot query all 1,000 each time the user starts up the phone, and it cannot do it periodically because with everyone hitting the same endpoint, it would be a bottleneck.

I do remember blockchain.info allowing you to query with your extended public key, I imagine that they iterate through the accounts the same way using the gap limit.


texts:
Hi how is blockchain actually stored on disk?

I noticed bitcoin uses key store database level DB but what is the structure?

https://github.com/bitcoin-core/leveldb-old/blob/bitcoin-fork/doc/table_format.txt

Here I don't get it... Does anyone has simple overview how it is stored?

I have also read this... but don't get it.
What are the keys used in the blockchain levelDB (ie what are the key:value pairs)?


texts: Why was noise XK fundamental pattern chosen in the transport layer (BOLT 08) of the lightning network

texts:
I am currently reviewing the transport layer of the Lightning network protocol. It builds on top of the noise protocol framework handshake patterns.

What I don't get: Why was the fundamental pattern XK chosen?

XK
  <- s
  ...
  -> e, es                  0                2
  <- e, ee                  2                1
  -> s, se                  2                5
  <-                        2                5

First of all why not KK? Nodes are announced via gossip and on my tcp socket I should see who connected to me being able to look up the static key of my peer. Was the reason so that lightning nodes could be private and in particular on tor?

Second of all why not using protocols without static keys? Is the reason that we wanted to have property 2 and 5 for initiator and recipient respectively?

Property 2:

  Sender authentication resistant to key-compromise impersonation (KCI) . The sender authentication is based on an ephemeral-static DH ("es" or "se") between the sender's static key pair and the recipient's ephemeral key pair. Assuming the corresponding private keys are secure, this authentication cannot be forged.

Property 5:

  Encryption to a known recipient, strong forward secrecy. This payload is encrypted based on an ephemeral-ephemeral DH as well as an ephemeral-static DH with the recipient's static key pair. Assuming the ephemeral private keys are secure, and the recipient is not being actively impersonated by an attacker that has stolen its static private key, this payload cannot be decrypted.

It feels like I have given the answer by quoting from the noise protocol framework page. But maybe I am mistaking so it would be great to get your insights.


texts: Bitcoin transaction confirmed and spend but not funds recieved

texts:
Transaction id
2d581849f11fd34a7d82a6913f78eaf19802bcd0c20aca5905f0d9aeab5f0832

Can someone plz advise what's the status


texts: Is performing a 51% attack / double spend on Bitcoin illegal?

texts:
Suppose I had an ultra large ASIC from the future, and could perform a double spend on the core Bitcoin network. At this point in Bitcoin's development, it is no longer a game - there's real money involved.

Would performing a successful double spend be considered illegal (e.g. in the U.S / Europe)?


texts: What different options are there to start bitcoin on command line?

texts:
I had troubles with my client on a Raspberry because it was using the wrong configuration file and I could not find any entry in the configuration file that referred to the right location of the data directory, but I knew it was beeing used correctly in the past.

I was trying to use -printtoconsole to debug the problem but that did also not work.


texts: How to get bitcoin address of any private key?

texts:
calling bitcoin-cli dumpwallet returns wallet private keys and addresses.

Example

L34D2hAS9KBJQzJkHtmNt1bdSJ18cQUvfSnJEqPKH2oUj6sBxvXt 2017-11-23T05:11:13Z reserve=1 # addr=1D2mnuj9qeRAzmw8mjLDciyvqzQiiYZCfE hdkeypath=m/0'/0'/1030'

Importing this private key to wallet using importprivkey command returns null on success.

How to get bitcoin address related to this private key? or is there's any way get this private key details like balance or addresses?


texts: Segwit: Arbitrary data storage in witness?

texts:
Let's say I want to encode the text of the King James version of the Bible into the block chain, one piece at a time (replace this with any zany idea to consume copious quantities of block space). OP_RETURN is impractical because I can only work with 80-byte chunks.

I notice that SegWit allows much more data to be stored - up to 3 MB/block - in witness data.

Clearly, I can't use a V0 witness program because my witness data must take the form

<signature> <pubkey>

However, I believe I can use a V1 witness program. Scripts with that version won't be supported immediately after SegWit deployment, but I notice this in BIP-141:

  If the version byte is 1 to 16, no further interpretation of the witness program or witness stack happens, and there is no size restriction for the witness stack. These versions are reserved for future extensions.

So here's my plan. I'm going to create an output script of the form:

<0x01> <0x0000>

This is a V1 witness program. According to BIP-141, the witness program is not to be interpreted, and the subsequent witness stack will have no size restriction.

Then I'm going to spend that output with a witness transaction input. The witness of my transaction encodes a thousand bytes of text.

When I publish this spending transaction, it will be propagated by nodes. They can't reject it as invalid because that would break forward compatibility when V1 scripts are introduced. BIP-141 says nothing about whether or not such transactions should be relayed (nor does BIP-144), so I assume they will be.

As long as I pay a sufficiently high fee, my transaction should eventually be mined. I even get a 75% discount over using OP_RETURN because my text is encoded in the witness.

And there's nothing the protocol will do to stop me. Or is there?

Edit: to make things simple, assume SegWit has been widely-deployed and that most nodes understand V0 witness programs. Clearly, non-SegWit nodes will not relay a witness transaction because it will be considered non-standard. I'm interested in the behavior of SegWit nodes.


texts: Meaning of the Tables in the Blockchain Database

texts:
I've grabbed "Abe" and have started processing the blockchain into a database, but I can't really find documentation on what the various tables mean / are / contain.

Here's the list:

abe_lock
block
block_next
block_tx
block_txin
chain
chain_candidate
configvar
datadir
magic
orphan_block
policy
pubkey
tx
txin
txout
unlinked_txin

I can make some guesses, but documentation would be better. Can anyone explain what's in each of these, or point me to some documentation?

Thank you, if you can help!


texts: Is it possible to build bitcoin source code into a windows .exe file, using Ubuntu?

texts:
I am using an ubuntu machine and have compiled the bitcoin source code a few times without issue. I am able to use bitcoin-qt just fine in the terminal to load the interface, but I'm wondering if I can make the code into a .exe file and put that file onto windows and run the client there without dependencies.

Is it possible to do that? Or will I have to install the dependencies on windows and compile in windows into a binary that requires no dependencies?


texts:
I understand that when I'm doing a transaction, I'm locking those bitcoins to whoever provide the solution to a script that has the hash I posted.

But, where does the hash get written?

I would assume that it is not in the blockchain, since this payment system is done so we can save space. I can imagine that the nodes store a database of hashes of scripts previously written on the blockchain, so when they see a script hash, they can find the correct script for it. Another option was that the recipient would provide the script at the time of the transaction, but then the other nodes would not be able to verify the script's end result, because the script would not be on the blockchain.


texts: What is the difference between an SPV wallet and an API wallet?

texts: I understand what an api wallet is, but I'm unfamiliar with what an SPV wallet details. I'd like a technical explanation on what an SPV wallet is, how it differs from traditional thin clients and how I could go about implementing one.


texts: How do I import a wallet into Bitcoin core?

texts:
I have the public address, and the private key of a BTC wallet. How can I import this into bitcoin core so that I can use it to sign messages?

I need to be able to sign a message to show that I possess the private keys for an account.

Thanks for any help.


texts: Zeusminer Blizzards no longer working with bfgminer 5.0.0

texts:
I was mining off a raspberry pi with some zeus blizzards, I've had to format the SD because it got corrupted and so I took the chance to install the latest bfgminer.

the raspberry is running raspbian and I've installed bfgminer following this install guide on BitcoinTalk.

sudo ./bfgminer -d? -D

or

sudo ./bfgminer -S zeusminer:all -d? -D

prints out

[2015-01-15 18:01:27] setrlimit: Soft fd limit not being changed from 1024 (FD_SETSIZE=1024; hard limit=4096)
[2015-01-15 18:01:27] Started bfgminer 5.0.0
[2015-01-15 18:01:27] lowlevel_scan: Found vcom device at dev_t:01bc000000000000 (path=/dev/ttyUSB1, vid=0000, pid=0000, manuf=Silicon Labs, prod=CP2102 USB to UART Bridge Controller, serial=0001)
[2015-01-15 18:01:27] lowlevel_scan: Found vcom device at dev_t:00bc000000000000 (path=/dev/ttyUSB0, vid=0000, pid=0000, manuf=Silicon Labs, prod=CP2102 USB to UART Bridge Controller, serial=0001)
[2015-01-15 18:01:27] Devices detected:
[2015-01-15 18:01:27] Timers: Using clock_gettime(CLOCK_MONOTONIC_RAW)
0 devices listed

and

lsusb

Bus 001 Device 002: ID 0424:9514 Standard Microsystems Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 001 Device 003: ID 0424:ec00 Standard Microsystems Corp.
Bus 001 Device 007: ID 10c4:ea60 Cygnal Integrated Products, Inc. CP210x UART Bridge / myAVR mySmartUSB light
Bus 001 Device 006: ID 10c4:ea60 Cygnal Integrated Products, Inc. CP210x UART Bridge / myAVR mySmartUSB light

so the blizzards are connected indeed to /dev/ttyUSB0 and ttyUSB1 but bfgminer doens't not recognize them. Should I add something in the install procedure to enable the zeusminers? They were working until a couple of days ago before the SD formatting procedure.


texts:
What are some ways that the powerful elite can thwart cryptocurrencies?

Cryptocurrencies appear to be not susceptible to most forms of power, regulation, or control. Due to their decentralized and anonymous nature, they are often touted as an antidote to government, Wall Street, etc manipulation through currency and money.

How accurate is this? What are some ways that an actor who has an interest in say the dominance of Wall Street or just any old reason for using their power to control otherwise free actors could do so through cryptocurrency economies?


texts: Cryptocurrency with addresses that cannot collide?

texts:
I had originally posted the following question here:

Is it possible to have a cryptocurrency based on email address?

And now I have come across The Large Bitcoin Collider

I have read on Bitcoin Stackexchange and other places people writing how improbably it is to collide with an existing address with a balance. Some even wrote its astronomically improbable.

But if you look here you'll see that the LBC in a matter of few months has already found over 15 addresses with balance, of which one contained 0.54 BTC: LBC Trophies

Imagine once it starts harnessing more power from users?

Clearly this is a big problem. Right now a Bitcoin address with some balance is akin to a cabin in some woods with no door and a small pouch of gold waiting to be discovered.

My question is, what is the solution to this going to be?

I have a few comments which I'll consider unacceptable. I am listing them and their reasons.

Comment: Even bank account passwords can be cracked and your amount could be stolen.
Invalid: I am not talking about someone trying to specifically attack your bank account with number 123456789 with bank ABC with password wtHMcQ^KB;i9UA6ZPI,VE!r<:3xLkzDlXg.[N0{~214o*/h+(W>O@me?-J_#&|`8. I am talking about attackers randomly going through private keys and checking if they have a balance.

That's it for now.

I am going to look forward to some good solutions.


texts: How can I get email notification when I get or make a Ripple payment?

texts: What's the easiest way to get an email notification whenever I receive or send a Ripple payment?


texts: How to send/receive Bitcoins from cold wallet?

texts:
I have generated a Cold Wallet using bitaddress.org (pub + priv key)

How do I send / receive Bitcoins from / to the generated addresses?
Is there something I should mind about?
Receiving seems to be easy: Just send Bitcoins to the generated Bitcoin Address, correct?

I have no problem to use the commandline.

Is there a way to do this (send / receive) without needing to use my private key on a computer connected to the internet?

Thanks for helping


texts: Is it possible to pay externally for unconfirmed transaction?

texts:
I have a strange situation. I bought some bitcoins with fiat currency and the seller (trading site) have sent my bitcoins to my private wallet. But the problem is that the transaction has a too low fee (143 sat / byte) to be mined.
The transaction was sent about 110 hours ago and it is still unconfirmed. It seems that the transaction won't be confirmed or it will be dropped from the mempool.

I can not reach the seller right now (they are ignoring me). So, I would like to pay some miner to mine, my transaction because if it is dropped from the mempool I will lose a great portion of the money.

Is it possible to pay someone (for example to mining pool) to include my transaction in the block chain? For example, I can send some amount of bitcoins with good fee to the miner if I would know that my transaction would be mined.


texts: How to explore transaction chain via Original Bitcoin API as blockexplorer does it

texts:
Is there any possibility to explore transaction chain via Original Bitcoin API (https://en.bitcoin.it/wiki/Original_Bitcoin_client/API_Calls_list) as the blockexplorer does it.
If not, why?


texts:
Is it possible to communicate with an electrum server using http? I'm interested in building a browser extension.

I also see this message on the electrum chrome plugin

  Unfortunately, all public Electrum servers have upgraded to a version of the protocol this extension does not support


texts: Deriving payable address from mnemonic using BIP44

texts:
I'm trying to go from seed phrase/mnemonic to payable address using BIP 44.  Here is a simplified version of the code I'm using.  However, when I compare with https://iancoleman.io/bip39/ the private, public, and address don't match up.
var mnemonic = require('bitcore-mnemonic')
var bitcore = require('bitcore-lib')

var code = new mnemonic("width bicycle axis tell burst outdoor tray episode where they forest meadow enhance twin focus");

var xpriv = code.toHDPrivateKey(bitcore.Networks.livenet);
var derived = xpriv.derive("m/44'/0'/0'/0/0")

var privateKey = derived.privateKey
var publicKey = derived.publicKey
var address = new bitcore.Address(publicKey)

console.log(`address: ${address}`)
console.log(`privateKey: ${privateKey}`)
console.log(`publicKey: ${publicKey}`)

This code outputs:
address: 14TomZRSGPtoPGy9HZA8WfX2veMbDXyAAJ
privateKey: 34fb6aee170bb41fe47f97ab601fea589620cf182ecf031688c25e5491c2c06f
publicKey: 027869eb83bbb44621c868fbd2a31daed4a0f8dbaa73d3fd79a597cdb1afcc9d1d

However when I go to https://iancoleman.io/bip39/
it give as the first address with this seed phrase to be:
path: m/44'/0'/0'/0/0
address: 1BogrbApan5Q9xEFEzwPioRu3ogYkzAQZU
public: 0236f0bf97fa766301e1137bef8377e6f6063b8a576bda57220c7ab6cf531cc992
private: L46hcht5ue2tsSKmPEV2v41CrGU8DEJAP1w7XYPbvJ72v5NBPsPF


texts:
I found this script: https://github.com/jgarzik/pyminer
But it uses getwork RPC call, which resulting me this:
error code: -32601
error message:
Method not found

From https://en.bitcoin.it/wiki/Getblocktemplate:

It supercedes the old getwork mining protocol.

Does it mean that getwork is no longer an option for miners? If so, how do I solo mine with getblocktemplate?
I never worked with this protocol, but from what I read on wiki, it apparently forces me to connect to pools. My task is to do solo mining by all means.
Could you please provide or refer to example Bitcoin RPC call, that would:

Get a job to mine
Send mined block hash with all the mined info (nonce, etc.)

If possible, please, do not refer me to third-party software like bfgminer, etc. I'm implementing my own miner, and I need to know RPC calls to do it.