texts: Bitcoin Transaction using API with Custom Fees

texts:
I want to transfer Bitcoin from one individual address to another using API. But I want to set Transaction fees as per my requirement. So How can I do it ?

Right now I am using blockchain-transaction - npm api for transfer bitcoin from one address to another. So please shade some lights on this.

var bitcoinTransaction = require('bitcoin-transaction');
//Send all my money from wallet1 to wallet2 on the bitcoin testnet
var from = "mm3gdVh8n6YtcNyaTKYkveB6yTME7aDWNJ";
var to = "mgPUfqJk4X6gE4P5Do5RfpkTFsYmsSjCya";
var privKeyWIF = "cNZi8iySqBToXMpcsQaHKD5uv7HExBQJBSi4dTg3ZPaEzeNAzvbj";    //Private key in WIF form (Can generate this from bitcoinlib-js)
bitcoinTransaction.getBalance(from, { network: "testnet" }).then((balanceInBTC) => {
    return bitcoinTransaction.sendTransaction({
from: from,
to: to,
privKeyWIF: privKeyWIF,
btc: balanceInBTC,
network: "testnet"
});
});


texts: When I opened the bitcoin client, I found that it was "synchronizing block headers". Does this mean that the client first downloads block headers and then downloads block bodies? What kind of file does the header of the downloaded block is stored in?


texts: Wallet is encrypted and currently locked. How can I get it decrypted (unlocked) - I have my password!

texts:
I have run into the problem of my wallet being encrypted and currently locked. I am using Bitcoin-Qt. I have my password to unlock it, but I can't find an area in the interface to unlock the wallet.

Where do I enter my password to unlock?


texts: Which is the better estimator for future mining intervals, the 10 minute protocol target or the observed, historical average?

texts:
The Bitcoin protocol is designed so that the network difficulty is periodically adjusted so that new blocks are mined on average every 10th minute. However, looking back the last 10 years, it appears the observed, average mining interval is 567.35 seconds. I calculated this by subtracting the timestamp of block nr. 573,795 with the timestamp of block nr. 0 and dividing by 573,794. I know block timestamps aren't that accurate, but this error should be negligible.

Bitcoin mining can be modeled as a Poisson process with certain simplifying assumptions. If I've done the math right, the 95 % confidence interval of a Poisson process with λ = 1.0575 (historical average nr. blocks mined every 600 seconds) and n = 573794 (current nr. of historical block intervals) allows for an actual mining interval no higher than 568.1 seconds, an error bound which is a long way from the 600 second block interval predicted by network difficulty.

I'm aware of at least one reason why there's a discrepancy, and that's the 2016 block difficulty adjustment interval. This was discussed and answered in a relation question here. But is this the only reason why historical block intervals are shorter than the mathematically predicted block intervals? If we experienced a long period of consistent decline in network hash rate, would we see a similar, opposite effect, where the observed block intervals consistently exceed 600 seconds?

Bottom line question is... for block intervals in the future, is it best to assume the target block interval of 600 seconds, or an interval that is slightly lower or higher than this? If so, how much? This has implications, e.g., for designing predictive time series models in finance.


texts:
I am moving over from Multibit classic to HD. I am not particularly technical so this may be an obvious question, however I can't find the answer I want in Multibit's help section, so here I am.
On the HD request payment field, there are places for amount,(in BTC and Fiat currency), Recipient (one of my addresses)QR code label and private notes. Where is the section to fill in the address payment is request from? In classic I could copy and paste the address. In the HD help section it says you can also do this, however I cant see where you enter the details. Have I missed something blindingly obvious? Thanks.


texts: While re-calculating the difficulty every 2016 blocks, how do nodes agree on the new difficulty? There is no unique timestamp on the p2p  network, because nodes can lie about their time stamps. Let us say I calculated the new difficulty and found N, another person found N+3. How is the consensus about the new difficulty arises? The formula depends on the time elapsed for the last 2016 blocks, so without a consensus about time stamps, how do we arrive at a consensus about the new difficulty?


texts: Incentives against selfish miners with 51% power

texts:
To me the situation of a '51% miner' is much like a government printing money - when they do, they get to finance their budget deficits as they get to spend the money first (when prices haven't changed yet). However, when that money gets into the system and people realize there's more money in the system, it leads to inflation that reduces the value of the currency (much like the reduction in the price of BTC). What stops a selfish miner with 51% mining power from double-spending like crazy in the short term before the price of BTC has had time to react, then pull out of BTC altogether? Then there would be no loss of wealth that the whitepaper says disincentivizes greedy attackers?

Thanks for your response in advance!


texts: how to set the conf file ,if my wallet is encrypted

texts:
I'm working with bitcoin-qt to send payments, the config file is set to work with JSON-RPC.
it's include the rpcuser and rpcpassword, all calls I make to the wallet works fine, on the UI of the bitcoin-qt.exe I wanted to encrypt the wallet so every send payment I do from the UI will ask me for user password, I did it from setting->encrypt wallet.
After that all calls from JSON RPC I get an error "The remote server returned an error: (500) Internal Server Error." . should I add something in the conf file ?


texts:
Let's say that 7 users want to spend money from a Bitcoin multisig address. The approval of funds from this address requires the signatures of A (the leader), either B or C (two managers), and 2 of 4 members of a board of investors (D, E, F, G). So if A, B, D, & G all submit their signatures then the transaction should be considered valid. However, even if B, C, D, E, F, and G all submit their signatures, A can veto by not submitting his/her signature.

Does the Bitcoin protocol currently support advanced transactions like this or does it only support basic M-of-N addresses/transactions?


texts: Can I make Bitcoin transactions without the involvement of a bank account whatsoever?

texts: I am a web designer and I don't have access to a bank-account (and therefore, credit/debit-card) and I am not old enough to open a bank-account yet. Could I use a Bitcoin wallet to receive money and store it there as long as I want (and possibly, send those Bitcoins) ? Paypal would be ok except they only allow you to receive a limited amount before you are required to connect your Paypal account to a bank-account.


texts: Bitcoin Testnet API that allows transaction lookup and submission of raw transactions

texts:
I'm looking for a well developed, maintained and stable API allowing to access bitcoin testnet. Something like Infura for Ethereum. Googling gives many results, but can somebody point me out what is really in use?
In the moment for me BlockCypher looks the best, but can I really trust it?
It would be nice if the API was free, but it not necessarily has to be.
Cheers


texts:
https://blockchain.info/unspent?active=1AeRh3hBFCCouBukF3NrxtHjar1aBQToh4&format=html

help me stop it or tell me how i can stop it

Final Balance   $ 18.58


texts: Does a wallet containing multiple addresses have a single private key?

texts: Title says it all. Would one private key enable you to recover all the addresses in your wallet? Or does a wallet just contain a series of key-pairs?


texts: Can op codes be used instead of signatures?

texts: Are there any op codes or combination of opcodes that can be used instead of a digital signature when creating a transaction?


texts: Does using centralized services defeat the benefits of a distributed blockchain?

texts:
I'm reading about the blockchain concepts and there is one big thing i don't get: why in fact you need blockchain services such as https://www.ibm.com/blockchain/ or https://azure.microsoft.com/en-us/solutions/blockchain/?v=17.23h

The entire concept of blockchain is that it is decentralized, doesn't going to a blockchain service break that idea entirely?

Why would someone need blockchain as a service?


texts: Where is bitcoin.conf and why doesn't bitcoind find existing datadir v0.17.1

texts:
Just built no gui, no wallet bitcoin on WSL Ubuntu Bionic, Bitcoin v0.17.1.

I want to experiment with bitcoin-cli.

I followed recommendation to run bitcoind -princonsole and it says:
Using config file

  /home/<myusername>/.bitcoin/bitcoin.conf

This file doesn't exist.

I followed some dense discussion on how should this behave to make dumb users happier on github, supposedly there were some merges, but frankly, I have no clue what was the final conclusion and what is or isn't in 0.17.1

Eventually, I understood that datadir must be specified first.

But that doesn't work for me.

~/bitcoin$ bitcoind -datadir /mnt/d/blockchain -txindex
Error: Specified data directory "" does not exist.

/mnt/d/blockchain definitely exists.

Thanks for any help.

 Many thanks to Nate Eldredge for pointing out a dumb error of mine and hope someone can help parsing and shedding some light on this:

https://github.com/bitcoin/bitcoin/issues/10746

Blockchain download has started and now I am waiting for the end result.


texts: transfer funds from Mt.Gox after the crash of 2014

texts: By now, 25/03/2014, you can view your funds on the Mt. Gox website. I have some euro's parked over there. Is there a way to transfer them. Is there a procedure you can follow?


texts: How can a Bitcoin Oracle ensure that the money can't be respent?

texts:
Suppose I modify the requirements of the Inheritance Scripting Sample where I need to make sure that the prior BTC is "guaranteed" to be available and not reduced or re-spent prior to either of the preceding events:

The 18th birthday arrives
The oracle verifies that the man is dead

With the additional requirement that the Oracle can't hold the transaction hostage for a ransom (since it would know how much is due to the payee), is there any way to use scripting to cover the condition that the previous funds can't be respent?  How can this be done?


texts:
I'm a bit confused.

According to https://bitcoincore.org/en/2018/02/26/release-0.16.0/#hd-wallets-by-default HD wallet is enabled by default. However there is still keypool option of bitcoind which sets how many addresses will be pregenerated on wallet loading. keypool assumes regular wallet backups in order to not to loose keys generated above keypool value and keypool restore.

So, my question is: with HD wallets does keypool option have any meaning? And do I still need to do these regular backups?


texts: What is the highest recorded difficulty in the main net?

texts: What is the highest recorded difficulty in the main net and which blocks was it used for?


texts: How can I validate the amounts of these wallets (https://bitinfocharts.com/top-100-richest-bitcoin-addresses.html) on my bitcoin full node?

texts: Followup question: I am running a bitcoin full-node and it took a month to sync the blockchain. I did not create the full-node with a bitcoin wallet. I stumbled upon this 'importaddress' command (https://bitcoincore.org/en/doc/0.16.1/rpc/wallet/importaddress/) and I was wondering if I could somehow run the command without a bitcoin wallet or find a way to attach a bitcoin wallet and rescan the blockchain without having to restart the entire downloading of the blockchain again. Is it possible to attach a wallet without re-downloading the entire blockchain?


texts: Transfering btc from blockchain to electrum wallet, still unconfirmed

texts: i transferred btc from blockchain to electrum wallet. it has like 132 confirmations but on blockchain it's still Pending: 0/3 Confirmations Status. I paid fee and everything. Is this something normal or Is there anything happening? this is my first post here. thanks much


texts:
I am going to run a bitcoin core on a Linux server (Ubuntu 20.04). I don't have enough storage to store blockchain data. Therefore, I want to save the data over an NFS server (CentOS release 6.10). However, I get an error when I set the -datadir to the shared folder.
The content of /etc/exports file in the NFS server (I've seen the configuration from here):
/home/storage/  BITCOIN.CORE_IP(rw,sync,no_root_squash,no_subtree_check)

I mounted the remote shared directory in the Ubuntu 20.04 Linux server using the following command:
mount NFS_SERVER_IP:/home/storage/ /root/blockchain/

everything works fine, and the file system disk space usage report is: (df -h)
Filesystem                   Size  Used Avail Use% Mounted on
NFS_SERVER_IP:/home/storage/  1.0T  682M  1.0T   1% /root/blockchain

After running the following command to change the data directory to the shared directory:
./bitcoin-0.20.0/bin/bitcoind -datadir=/root/blockchain

I get the following error:
Error: Cannot obtain a lock on data directory /root/blockchain. Bitcoin Core is probably already running.

I should note that the shared directory is empty before running the bitcoind, then after that, it contains an empty file, which name is .lock. Moreover, If I set the -datadir to any local folder, it will not return any error!
Thanks.


texts: Bitcoin QT error. How can I prevent corruption of database?

texts:
So I turn on my computer this morning, and I find Bitcoin QT has quit of its own accord.
I try to turn it back on and I get this message.

"Bitcoin - Error System error: Database corrupted"

I'm fairly sure Windows 7 restarted itself to install updates. Is this what caused the corruption?

Luckily, I have zero bitcoins, and I've reinstalled Bitcoin QT without any problems, but this will stress me out if I want to mine bitcoins while out of town.

Apparently, if the database is corrupted, you may have lost your wallet and all your money!

My question is, is this true, and how can I prevent this error from appearing again? What can cause it? I've turned off windows automatic update, so that should mean we're okay? What happens in a powercut? Wish Bitcoin QT was more robust :(

update Even weirder, I gave the corrupted Bitcoin QT a try and for no reason at all, it started and didn't give me the error. Really scared of loosing all my money. Can someone explain what's happening? Thanks a lot guys.

update Nope. Dispite working, it is still corrupted. It gets stuck on 86 weeks forever.

Tried to get in via bitcoind to reindex the database:

Tried uninstalling everything and reeboting my computer and resinstalling bitcoin-qt:

Thought it was working, but the second it got onto 85 weeks remaining:

Gentlemen, please help. Logically thinking about it, it must be the same database it's using, that somehow survived the reinstall. Maybe if someone could point me towards where this database is stored so I can delete it manually?

Brand new computer, 64 bit genuine windows 7. Barely any programs installed. Can't believe how flaky this open source software is.


texts: How to fork an Altcoin Which has 0 Reward Block to continue mining after the LAST POW BLOCK

texts: Im trying to learn how is it possible to Hard Fork an Altcoin Blockchain to Continue the Mining Phase after the LAST POW BLOCK. The Block Reward is already 0 and the LAST POW stops at Block 8000. And want to know if there is a way to continue the mining after the 8000 without any SYNC Problem and Stuck Problem.


texts: Get value from leveldb bitcoin using node.js?

texts:
I request information about the block 100001 using leveldb and node js.
Below is my code example.

var level = require('level');
var db = level('E:/download/blockchain/block');
var str = '630010ec274a07f88f9b407da4753f91e15ee6bdf52f0bbc0dfc0dadb6815a6c24';
db.get(new Buffer(str, 'hex'), {
    encoding: 'binary'
}, function (err, value) {
    if (err) {
        console.log(err);
    } else {
        console.log(value);
    }
});

And i get this answer:

���Zl$]
    at E:\Work\Crypto\node_modules\levelup\lib\levelup.js:164:15
    at E:\Work\Crypto\node_modules\encoding-down\index.js:51:21

Why is this code throwing an exception, I can't understand. A little help will be appreciated, Thanks


texts: P2P getHeaders message - how to get block locator hashes

texts:
I'm trying to build my own block explorer
So that I need to use p2p bitcoin protocol. For that I'm using btcd (golang) lib.

According to bitcoin book I have to send version message (and receive verack message back) to init the connection, then I will send getheaders message in cycle.

Now, imagine I am a new peer and want to download all the blockchain (actually I want to receive block hashes with getheaders (2000 per tick) and for each block hash I want to receive a block itself to process it and put blocks data in my mongo database)

If I am new peer in the network, how should I send first (and next) getheaders message, I don't quite understand where should I get block locator hashes and how to form the message?


texts: What protocols are built on top of Bitcoin?

texts:
Mastercoin is described as:

  "both a new type of currency (MSC) and a platform. It is a new protocol layer running on top of Bitcoin like HTTP runs on top of TCP/IP. Its purpose is to build upon the core Bitcoin protocol and add new features".

Are there any other protocols or similar built on top of the Bitcoin protocol in this way?
(As an aside, the way Namecoin uses a Bitcoin-like P2P model to act as an alternative, decentralized DNS is interesting...are there similar things built on top of Bitcoin itself?)


texts:
Can any expert help me understand the need for the following members of CNode in src/net.h

std::deque<CSerializeData> vSendMsg;
std::deque<CInv> vRecvGetData;
std::deque<CNetMessage> vRecvMsg;

If I understand the source code correct, vRecvMsg is for storing the input messages and vSendMsg is a queue for output messages.

Why do we have different form of queues [i.e. CNetMessage and CSerializeData] for input and output?
What is the purpose of vRevGetData? Can you please help me understand also the concept behind the usage of this ?


texts: What is it that makes BIP149 safer to activate than BIP148?

texts:
There are currently two BIPs floating to enable a "user activated softfork" of Segregated Witness.

BIP148 is meant to activate by flag day on August 1st 2017 whereas enforcing nodes stop accepting blocks that don't signal readiness for segwit.

BIP149 proposes to initiate a second activation process based on BIP8 once the current versionbit (BIP9) activation times out unsuccessfully. From my understanding, BIP8 is the same as BIP9 except that at the end of the activation cycle it goes into LOCKED_IN instead of timing out.

Isn't it just a semantic difference, whether a subset of all nodes defines the proposal as LOCKED_IN or the same subset of nodes outright rejects non-signalling blocks until the proposal goes to LOCKED_IN?

What makes BIP149 safer to activate?

I don't see a significant difference or that the former would decrease the chance of a chainsplit significantly except for the longer waiting time until it is activated.


texts: Can bitcoin system be modded to work without internet

texts: Is it possible for bitcoins to manifest itself as  concrete currency so that it can be used as paper money ?


texts: Varying mempool statistics across multiple sources

texts: I understand that each node is different and will have a different mempool (and size). But in looking at https://tradeblock.com/bitcoin/ it is showing a mempool size of around 20MB (http://bitcointicker.co/networkstats/ shows similar mempool size of 20MB). But https://blockchain.info/charts/mempool-size is showing a mempool of 103MB (https://jochen-hoenicke.de/queue/#24h showing similar 100+ MB size). Neither site explains how they configure their mempool. tradeblock.com and blockchain.info are referenced from many sources - do you know what can explain this big difference in how they report mempool size? thanks


texts:
The 'decoderawtransaction' RPC method of the Bitcoin-QT client gives a JSON object with an array of addresses in each UTXO. For example, when I run:

decoderawtransaction "01000000010fb72b5d299f095c3d3abc2130f20ce59d0ed08d56b3f247d6ae554f200eb561010000006a473044022073717edfcde0200f8aca33b6ff4f60a4aa84c6692cd1713876d94f3f19013f6d022057610074eef8285082cb9943913040031869cc98bc71642a3dc5e085a19a1805012103f071bc0f54b95e9049ba515f19cbfb647605a9f1d2f002b4e70ec548af5fbf5bffffffff02b02bc37d010000001976a9148037b2fd4114347070236b37f792966ade2bc4a688acd0ce4101000000001976a914336e5078d05a350fb5e6cdf8fc15d826e625423888ac00000000"

I get back the following JSON:

{
  ...
  "vout":[
    {
      "value":64.04910000,
      "n":0,
      "scriptPubKey":{
        "asm":"OP_DUP OP_HASH160 8037b2fd4114347070236b37f792966ade2bc4a6 OP_EQUALVERIFY OP_CHECKSIG",
        "hex":"76a9148037b2fd4114347070236b37f792966ade2bc4a688ac",
        "reqSigs":1,
        "type":"pubkeyhash",
        "addresses":[
          "1CgxDbrb9d18DFvQn6DW8ij3c6ARpipehU"
        ]
      }
    }
  ]
  ...
}

You can see here that "addresses" is an array. Why is this an array? Can one UTXO send to multiple addresses? I know P2SH addresses can pay to an address that can be redeemed by the use of multiple addresses, but I'm wondering about sending to multiple addresses without the use of P2SH addressses. What would be the format of the scriptSig/scriptPubKey for doing so?

Also, if you only have the P2SH address, then can you determine what the requirements for redeeming from that address are?

Thanks!


texts: Is there actually such a thing as "blockchains" being used right now for actual things?

texts:
In the last few years, I've heard "blockchain" and "blockchain 2.0" and many other such buzzwords repeated so many times that I'm beginning to wonder if I've missed out on something major.
I have had Bitcoin Core installed basically since it became a thing. My Bitcoin blockchain is over 300 GB by now. I use Bitcoin whenever I'm allowed to (extremely few services even accept it still) and feel like I can part from some, which is rare to say the least.
A lot of people seem to be pretending as if there is a whole "world" of cryptocurrencies being used and "smart contracts" being used and "Ether" being a whole major thing and... I don't notice any of this. Again, it's extremely rare that I find anyone who actually accepts Bitcoin, and I never hear anyone mention "Ether" or any non-Bitcoin cryptocurrency. People seem to have no idea that they exist at all.
Out of those who used to accept Bitcoin, many have actually stopped doing so recently as well.
I couldn't wish harder for this to become a thing, but I just don't see it. So what's with the constant "blockchain" talk? Do they truly have no idea what they are talking about? Are they consciously talking nonsense to get fiat money from stupid investors? (How can people who have lots of money be that stupid/ignorant?)
Am I missing something? Is there some kind of decentralized network right now which is actually being used which uses Bitcoin or "something else" and which I've somehow not noticed? Are they just talking nonsense?
Ever since I first heard of Bitcoin a decade age, I've been actively searching for ways to actually make a living using this system. It seems like it could still be year 2009 in terms of adoption/widespreadness.
Please don't link me to yet another slick website which links to some "whitepaper" and mentions that you should sign up to their newsletter for "exciting news". I'm not falling for that stuff again...


texts: How can a website detect when bitcoins have been deposited?

texts:
If I want to have a website that can credit bitcoins to a user's account when they deposit bitcoins, how can I have the website automatically detect when the bitcoins have been received into to the wallet address given to that customer (belonging to me), and consequently update the website to reflect their new balance automatically - without having to manually check my wallet.

I'm not interested in using existing payment services for this, but rather I'm interested in the coding principles required.


texts: How do we verify the signature on a raw transaction using Bitcoinj?

texts:
I managed to create a raw tx using Bitcoinj but not able to figure out how to verify its signatures.
Assuming I know the addresses corresponding to the (supposedly) unspent outputs used as inputs to the Tx, what is the easiest way to verify the Tx?


texts: Determine which are the successful transaction using BlockChain API

texts:
From this BlockChain API
http://blockchain.info/address/1AJbsFZ64EpEfS5UAjAfcUG8pH8Jn3rn1F?format=json

Are those considered as successful transaction?
If not, I would like to know which are successful inputs(receivables) for that sample address.

thanks!


texts: Can a Butterfly Labs Jalapeño be used to mine Zetacoin?

texts: Can my Butterfly Labs Jalapeño be switched to mine Zetacoin?


texts: Bitcoind (linux) CPU usage through the roof

texts:
Basically I'm trying to keep a wallet on linux along with the RPC service so I can receive coins and poll the server periodically for transactions.

I'm trying with both 0.8.1 and 0.8.5 and CPU usage is at 100%, running this on amazon and I get the same even with the xlarge EC2 instance. This has been going on for over 24 hours, had to force reboot the instance to be able to reconnect.

It's not even set to generate coins. gen=0

I guess I'd like to know if this is permanent, or a bug, or something I'm doing wrong? Or maybe it just takes a while to "sync" or whatever its doing then it will go back to "normal" and by normal I mean any level of CPU usage that isn't in the range of WTF and OMG.

Also tried sending myself some 0.01-0.05 btcs and they never made it. Maybe it takes a while to show up? Although blockchain says said transactions have over 100 confirmations.

TIA


texts:
I followed this tutorial https://litecoin.info/Debian_Linux_cryptocoin_mining_rig_setup_guide and set up a Mining rig (Debian 6.0.10). Sometimes I modified it (downloaded later graphics drivers than in the Tutorial sugestet etc) but it works and I can mine on a pool.

But I can mine only if I log in as root. If I log in as a normal user and type cgminer --verbose -T, I get the following error:

 [2015-02-15 22:36:50] Started cgminer 3.7.2
 [2015-02-15 22:36:50] Loaded configuration file /home/martin/.cgminer/cgminer.conf
No protocol specified
No protocol specified
No protocol specified
 [2015-02-15 22:36:50] CL Platform 0 vendor: Advanced Micro Devices, Inc.
 [2015-02-15 22:36:50] CL Platform 0 name: AMD Accelerated Parallel Processing
 [2015-02-15 22:36:50] CL Platform 0 version: OpenCL 2.0 AMD-APP (1642.5)
 [2015-02-15 22:36:50] Error -1: Getting Device IDs (num)
 [2015-02-15 22:36:50] clDevicesNum returned error, no GPUs usable
 [2015-02-15 22:36:50] All devices disabled, cannot mine!

I tried setting all privileges in the folders in root - which are used for litecoin mining - to 777 and to change the owner to the usual user, but it didn't work. I copied the file /root/.cgminer/cgminer.conf to /home/user/.cgminer/cgminer.conf, set the user and the right to this file, but this didn't solve the problem too.

But why can only root access the OpenCL functions which are used, why can not the normal user do so?

Thank you.


texts:
im reading up on this page ==> https://github.com/bitcoin/bips/blob/master/bip-0021.mediawiki

I am currently trying to incorporate a message in the qr code but when i proceessed the qrcode it pulled the amount address and amount correctly. but the label didnt seem to appear or the message at all anywhere. i am using blockchain.info and block.io.

I decoded the image and the string is what it should be.

Where is the message stored so customers can view it at a later time?


texts: bitcoin core, deleted receiving address?

texts: Hi I set an address on bitcoin core and after I just downloaded it for mac. It was taking a crazy amount of time to synchronise which I realised was normal. I sent some $200 to the adress and whilst mucking around with the settings i hit the reset button which at the time I thought would fix the synchronisation issue. Anyway I've searched many .dat files and the receiving address is deleted from my bitcoin core app. Will I still receive my funds? If not, can I recover them?


texts: Does sending from a green address improve my anonymity?

texts:
If I am interested in improving my anonymity when dealing with a merchant, does sending from a Green Address help?

My proposed steps for buying from a merchant as anonymously as possible would be:

1) Send coins to InstaWallet (connecting to InstaWallet through Tor)

2) Send coins from InstaWallet to merchant using InstaWallet's Green Address feature.

My theory is that the Green Address would make it much more difficult for the merchant to determine my identity, compared to sending the coins directly from my personal wallet. If I send the coins directly from my wallet, the merchant could likely trace the coins back to the exchange where I originally purchased them, and possibly issue a subpoena to the exchange (which likely knows my identity). Whereas, if I send the coins via a Green Address, the merchant could not trace the coins upstream at all - even if they issued a subpoena to InstaWallet, there should be no way to determine the original source of the coins.

Is my theory correct? Do Green Addresses help improve anonymity?


texts: Streaming API for confirmed transactions?

texts:
Is there an API that makes streams transactions as they're confirmed? Everything I can find seems to just be putting out unconfirmed transactions in realtime, rather than waiting for confirmation.

To clarify, I'm looking to stream all transactions, not just one wallet.


texts: Does value 'True' at the middle of stack is valid transaction?

texts:
If at the middle of the execution of scriptSig + scriptPubKey we get the value 'True', while there are remaining values or operators in the stack, is the transaction valid? Or should the stack be empty + top result is 'True' ?
I believe it is not because someone can just send unlocking script with the 'OP_TRUE' and cause any UTXO to be unlocked.


texts: Does bitcoin or Blockchain protect against malware attacks that install a trojan to steal data from a device, on which bitcoin application is installed? Cause a trojan can steal the user's private key, thus his bitcoins can be stolen.


texts: Is it more profitable to mine non-SegWit blocks

texts: The fees for a SegWit address are lower than non-Segwit ones. Is there less fees per block with Segwit blocks? Is it less profitable to mine Segwit blocks?


texts:
I am moving to Electrum from Blockchain, but I can't find any guides or tutorials on the internet that explain the process of tranferring a Blockchain wallet to Electrum. I have a multi-signature wallet by the way.

Thanks.


texts:
Could anyone tell if Ubuntu Server has any advantages over Ubuntu Desktop for mining?

Basically, here is explained that there should be no big difference since that the Server and Desktop are different by initial packages installed.

I am wondering:

if energy can be saved as you are not using graphical environment
if GPU would have better performance in case it mining PC is manage
by SSH connection against a monitor is connected to it when using
Ubuntu Desktop
if the mining PC will work better - I noticed that some icons (like updates) are not responsive on my Ubuntu Desktop after 24 hours mining a

Any others pros and cons about using server versions against desktop version that anyone can share will be helpful.


texts: How do people know how to construct the OPCodes?

texts:
The scriptSig is:

    OP_DUP OP_HASH160 404371705fa9bd789a2fcd52d2c580b65d35549d
    OP_EQUALVERIFY OP_CHECKSIG

How did people know that this was the correct permutation of OPCodes and data?


texts: I need to buy a gift card for PlayStation using bitcoins or altcoins. Unfortunately, there is currently no other payment method. Can someone help?


texts: How do you calculate the maximum number of Bitcoins?

texts:
I am unsure on the exact formula for bitcoin supply(have an idea below):
∑〖210000 x [50 x 10^8/2^i 〗] / 10^8 with limits 32 and i=0
And from this equation is it possible to calculate the number of coins  available at any given time (e.g When will 98% of Bitcoin be mined)?
Thank you for the help in advance :)


texts: Exact definition of "Liveness" and "Safety" properties in a consensus?

texts:
Two main properties of a consensus are "Liveness" and "Safety".

What are the exact and precised definition of "Liveness" and "Safety" properties in a consensus ?

Are the following definitions correct?

Safety: Achieving an agreement on a single state by all participants ?
Liveness: Possibility of updating this state with keeping the agreement ?


texts: Forgotten password for Bitcoin core wallet

texts: My old computer was trash my new computer btc core wallet with my private keys and password I made my backup wallet locked I forgot my password how can I find my password please help


texts: How and When are lightning channels disabled?

texts:
On the testnet and some mainnet there are channels which are disabled, so if you try to route a payment through them it failed with this as an error message. Reading through the RPC commands, it seems you cannot disable your channels. In some cases the node that has a disabled channel is still online, since you can still ping and connect to it.

So How does a node disable a channel, or part of a channel?


texts: Given the current hashing powers, what do pools actually do in practice?

texts:
Given the current hashing powers, what do pools actually do in practice to find a block?

Ok, so here is my thinking, please correct me if I'm wrong anywhere:

Here's the format of the block header, the thing which is actually hashed:

  version(4b) + prevBlockHash(32b) + merkleHash(32b) + ctimestamp(4b) +
  ctarget(4b) + nonce(4b);

So, canonically, what miners do is going through all the possible values of the last NONCE(4 bytes).
If we treat that as unsigned int, the range would be 0-4294967295.
Right now you can buy a 2Ghs miner for < $100.
Given that you have something that can hash 2GHs(very cheap solution, I'm not even talking about THs systems that pools reportedly have), you could bruteforce through the range of 0:4294967295 in less than 3 seconds.

So, the question is, what keeps mining in that ~10min period?

My suspicion is that its not that much of a problem to find a nonce anymore, its more a problem to find the proper block that will actually have a nonce.

If that is true:

a) what do miners do in practice, play around with the timestamp, or generate some transactions to change the merkle root?

b) is there any mathematical proof that such a block will ever be found? I mean, bitcoin not getting stuck, because of some unfortunate block having such a bad coincidence of bits that will endup blocking the result from getting enough zeros in the end to fit the target(I'm asking about mathematical proof that it is impossible).


texts:
Recently, the CEO of Ripple stated that more than 50% of the BitCoin miners are in China, therefore, were the Chinese
government to interfere, they could control BitCoin (I assume via a 51% attack, I didn't check details).

"“I’ll tell you another story that is underreported, but worth paying attention to. Bitcoin is really controlled by China. There are four miners in China that control over 50% of Bitcoin,”"

Is it true that 4 Chinese miners can control all of BitCoin?


texts: How to exchange bitcoins held in electrum to ethereum?

texts:
How to exchange Bitcoins to Ethereum through shapeshift.io or changelly.com, from Electrum bitcoin wallet to Jaxx ETH wallet?
In electrum wallet do I need to subtract the Bitcoin mining fee manually, or I can send all my bitcoins in the wallet to shapeshift/exchangelly?


texts: Why CBlockIndex does not store a vector of next blocks for forward iteration?

texts:
CBlockIndex stores a pointer to previous block..

Is there any specific reason why it does not store a vector of "next" blocks for forward iteration?

If you think, a typical tree (as data structure) has "parent" (pprev) and a list of "children".


texts: Create a Bitcoin wallet for users and get paid?

texts:
Im a crypto trader and investor with a big portfolio. At the moment my company is looking to use GitHub of Copay to create a Bitcoin wallet with my company name, I want do a good investment in hardware and software and marketing.

How can we recover this investment or how we can get paid developing this? Is it possible to add a transaction fee for my company? Is there are any code to do that?

How we can earn money?


texts:
I recently just installed the Electrum client and I have a couple questions.

Is a new address generated in the receiving addresses each time a transaction is made? It sounds like that in the documentation.
I was just testing the gap limit settings, and I lowered it to the default and now there is an address with a red line. How can I remove this address?
Is it possible to manually create a new address? Or do I just raise the gap limit?

I've used Google to look for some answers, but I am still very confused. Thank you for your input :)


texts: Is there a way to launch bitcoin-core and have it shut down when synchronized?

texts:
I use bitcoin core infrequently.  I don't want to have it running all the time, but I'm willing to (for now) devote disk space to having it stay current.  I'd like to be relatively current whenever I do start it up, without being weeks behind.

What I'd like to do is:

Once a week or so, start bitcoin-core up.
Have it shut down once it's caught up (I guess defined as "when the latest transaction is less than an hour old).

I know how to handle step one (via cron/launchd/etc).  What I don't know how to do is step 2: either having it terminate automatically, or using some kind of CLI-command to check the sync status every so often.

If the answer to this is "put in a feature request to bitcoin core", then I'd be looking for workarounds/alternate methods to use until that worked.

For the record, I'm on OSX, but in theory this question applies to all variants of the client.

Any ideas?


texts: How can we run regtest without transaction fees

texts:
We have setup a bitcoin network using regtest mode and found that there is transaction fee charge on each sending Bitcoin.

Is it possible set the payment fee to zero for each transaction?

We found that there is a setting in the conf file called paytxfee. We have tried to uncomment it, but the client complains that its missing.

We are using ver 0.11. How to get rid of the fee for each transaction?

I enclosed is the error message too.

  Pay an optional transaction fee every time you send bitcoins.
  Transactions with fees are more likely than free transactions to be
  included in generated blocks, so may be validated sooner.
  paytxfee=0.00


texts: As per my knowledge Xcurrent uses blockchain. But how it uses blockchain ? Xcurrent or Interledger protocol talk about ledger entries, I would like to know, do they really use blockchain as a ledgers in bank transfer or they use banks native ledgers like (databases or anything)? What is difference between general and sub-ledger?, is sub-ledger is referred as bank's native ledger ?


texts: Bitstamp: What type of order to place to buy BTC when the price drops to a certain value?

texts:
I am sure this is a simple question but I am having trouble with figuring out the type of order to place on Bitstamp.

Say the price is currently $1100 but I want to buy only if the price drops to $1000, what type of order would I place? I thought this was a "Stop" order, but the Bitstamp UI asks me to specify the amount to buy in USD if the price rises to my given value. I am worried that if I enter $1000 and place this order, my order will instantly kick in because the price is already above $1000.


texts: bitcoind: why sendmany allows only double-precision floating point numbers?

texts: I am switching from electrum to bitcoind. On electrum is function paytomany which accept usual bitcoin amounts like 0.0001. But why method sendtomany accept only double-precision floating point numbers? Maybe there is another option for that purpose and I just missed it?


texts:
Is there a website where I can compare several altcoins in one chart?

In particular, I am looking for a chart where each coin, that I want to consider, starts with the same value (say a value of 100$) at a certain date. With such a chart one could compare the performance of the altcoins.


texts: Instantaneous exchange/conversion of bitcoin into cash

texts:
My question is : how can some exchanges instantaneously convert bitcoins into cash, in light of the fact that it takes 10 minutes to "validate" a bitcoin transaction?
A bitcoin transaction takes 10 minutes to "validate". Yet some exchanges like coinbase allow merchants to instantaneously convert bitcoin payments into cash. In Automatically cash out bitcoin with zero exchange rate risk it mentions that :

When you enable "instant exchanges", bitcoin you receive for merchant
orders will no longer be sent to your Coinbase wallet. Instead they
will be sent directly to Coinbase and exchanged, ensuring that you get
the the exact local currency price that you set in the merchant tools.

When a person buys a product, then even though the purchasers bitcoin is sent directly to Coinbase, will it not be the case that it takes 10 minutes to validate, since it is just another bitcoin transaction? If so then how do exchanges like Coinbase allow one to convert bitcoins to cash immediately?


texts:
Can the receiver's email address be obtained from the Bitcoin address? I accidentally sent money to this address:

14gpxmEMrzCpEEp2GZhbUfP5cgBmwtVs9T

Thanks.


texts: How does the lightning network handle changing IPs?

texts: What happens if suddenly my IP/Onion address changes? Will that be a problem for the lightning network? Or could my node just simply update the network graph as long as its public key stays the same?


texts: Main Differences from Counterparty vs NXT Assets Exchange (SecureAE)

texts: What are the main differences from counterparty and NXT asset exchange? I've been testing out the nxt asset exchange using http://www.secureae.com and using counterwallet. They both seem to be solid products and they both use a separate coin to do their transactions. What other major factors does one need to know before going with one of these decentralized asset exchanges?


texts: Why am I not getting payments on my bitcoind on an amazon ec2 instance?

texts:
I have an amazon ec2 instance running a web server, MySQL server, and bitcoin daemon on ubuntu 14.04, and I ran ./bitcoind getnewaddress and the output was an address. I sent a few cents worth of bitcoin to that address, and I have been doing ./bitcoind getbalance for a few hours and still there is no balance.

Wondering if I needed to send to a particular accoutn instead of the main bitcoin daemon, I also sent a few cents to an address generated by ./bitcoind getnewaddress debug (just a test name) and did ./bitcoind getbalance debug. I have found nothing, I am not sure what the issue is. Port 8333 is open on the amazon vm, so I don't think the issue is there. bitcoind's rpc interface is running on port 8432 as specified by rpcport=8432 in ~/.bitcoin/bitcoin.conf. Any idea why I am not getting payments? I think there have been enough confirmations, I believe the number required is 6 required by default. I will check soon to make sure that there have been that many confirmations.


texts: What literal thing is determining the price of Cryptos / stocks?

texts:
Yes, supply and demand I know. But what literal thing is determining the price. When I see the price changing every second on Coinbase or Robinhood, what is controlling that. Is it an algorithm? What information does that algorithm take in? Is it just one algorithm determining this price, or are there different algorithms and it’s just an estimation? I have never found an answer to these questions.
What I want to know is what physical place is an app like Coinbase getting this changing price from.


texts: How can I tell if my Bitcoin wallet is working?

texts: I'm not sure if my Bitcoin wallet is working, is there a way to check that it's ready to go? I'm using Breadwallet for iOS.


texts: Is this calculation of mining probability using the Bernoulli trial formula accurate?

texts:
I'm trying to understand the formulas for successfully mining a block (without a pool) based on hashrate over time (i.e. to chart the probability of finding a block at various historical points compared to network hashrate at the time).

It seems like this post is exactly the formula I'm looking for, but it doesn't actually add up. I'm awful at math so I can't tell if I'm missing a step or if the post is wrong. If there's a better/more accurate way of figuring this out, please share, but I'm specifically interested in learning if this is wrong or not and why.

It says the probability of being the one to successfully mine a block with 13.5 TH/s and a network hashrate of 11,000,000 TH/s = 0.00000122

Then it says:

  Now, in a month, there are N=6*24*30 mined blocks. To find the probability of winning one award in a month, we use the Bernoulli trial formula

  N*p1*(1-p1)^(N-1) = 0.0026

Now when I put that in Excel with N=4320, I get .005243, I only come up with the same answer when I divide N by two for N=2160, but I can't figure out any reason for that to be the case. Am I missing something or is this just a typo? Is this formula even a good way of approximating this?


texts: What is the DAO, and what is its connection with Ethereum

texts:
So the DAO was hacked due to a vulnerability in the way they wrote their smart contract https://blog.ethereum.org/2016/06/17/critical-update-re-dao-vulnerability/

The Ethereum plan is to fork the chain to specifically prevent the attacker from being able to withdraw from the DAO account.

So what is the DAO's connection with Ethereum, and what is its purpose? Why is the operation of the DAO so cruical to warrent a fork? I also see mentions of a company called Slock.it being involved somehow, what was their role in this ordeal?


texts:
The bitcoin page here (https://bitcoin.org/en/you-need-to-know) says that bitcoins don’t allow chargebacks.

In the current system, credit cards provide a system of checks and balances and provide arbitration when there are disputes. If I buy a item on the internet and find out that I didn’t receive the correct item, I can complain to the credit card company, and they will look at both sides and make a decision whether my dispute is correct or not. Further, when I buy an item off a eCommerce store (which is going to become more and more prevalent in the next few decades), I cant check that the item I am receiving is correct or according to what the merchant said.

If I were to use bitcoins instead, I have no way to getting my money back, if the merchant turned out to be a fraud. As a result, I will have less trust on buying items off the internet, as a result, eCommerce wont work as a result bitcoins wont work. eCommerce is definitely going to be here, so this leads me to the conclusion that bitcoins maynot work, unless there are other services that provide that arbitration service. Are there companies that are providing that arbitration (insurance against fraud) for bitcoin transactions?


texts: What RPC can I use to query the balance of an arbitrary address

texts:
How do I get the balance of an arbitrary address using Bitcoin RPC calls? From the RPC calls I can see you are required to have the private key or an account to use the RPC.

For illustrations sake, if you could demo querying this address:

1HB5XMLmzFVj8ALj6mfBsbifRoD4miY36v

That would be great. Here is the actual balance for this address.


texts: What happens if everyone suddenly adops bitcoins, or it becomes very easy to create blocks

texts:
I understand that bitcoins are currently produced at ~25BTC/10 min

If I understand correctly how fast a block is created is what determines how fast bitcoins are created.

If everyone starts using bitcoins it will create huge demand and price will rise if miners can't keep up with the adoption rate.

If a new technology appears (assume accessible to everyone so the problem of attacks on the network by trying to create a longer block isn't there) this will lead to a huge supply of bitcoins.

I'm trying to understand the dynamics of these two factors.

Is there a self regulating way where a sudden huge increase in the ability to solve for the block and how fast would this be?

Would a huge demand be also somehow self regulating or will it just spike the price?


texts: Need help to try locate where my bitcoin went to. Was given a company wallet address to send my money to. I realise now I was scammed. Would you be able to help me locate exchange that my €5700 went to?


texts:
I understand that BIP91 needs 269/336 signaled blocks.
My question is is it a rolling window of any 336 blocks or are there activation periods of 336 blocks that start and end at predetermined block numbers?


texts: How do I reduce the Bitcoin transaction fee?

texts: I am using Bitcoin Wallet v5.09-v5.10 on Android 6.0.1. Is there a way to lower the Bitcoin transaction fee?


texts:
I've compiled the Litecoin source using a custom genesis block to create a simple Altcoin for fun.

I just have some questions about Bitcoin/Litecoin Qt.

When I mine a block using the generate command, Litecoin Qt doesn't seem to inform any of its peers, either that or the peers aren't picking up the mined block. Does anyone know why?
I modified the DNS seeds to use my own domain name instead of Litecoin's, except Litecoin Qt can't seem to use my domain name to find nodes. The domain just returns a list of A records pointing to potential peers. Have I set that up correctly?
Litecoin Qt also can't seem to download the blocks from it's peers the first time it launches, does anyone know why?
The blockchain based on my custom genesis block doesn't seem to sync, does anyone have any idea why?

I haven't modified any of the source code apart from changing the genesis block.

I have Litecoin Qt on my local machine and two VPS's hosting two nodes. My first thought was that maybe I need more than two full nodes to get things working?


texts: Wasn't 0-conf more secure than Visa, before blocks got full and RBF was added?

texts: RBF and full blocks make 0-conf useless, because it's easy to override. Wasn't it once useful? I've heard without those it's more secure than Visa in terms of double spending.


texts: What are the consequences of high orphan block rate?

texts:
I know the disadvantages of a high stale block rate include:

More opportunities for double spend attacks
Lower network difficulty making the network cheaper to attack

But I don't know how  even an orphan block could affect the network


texts: How bitcoin core bootstraps [in source code]

texts:
When the bitcoin core daemon starts first time it does not have the block database. It must be connecting to other nodes over network. But (I am assuming) it needs to know the at least one live node/peer address (may be more to be robust against down nodes) to connect to the network. Where in code that configuration is accessed? Basically looking for the home calling block of code.
I could try to go through the source https://github.com/bitcoin/bitcoin but I am sure someone will see this question who can point me to the source file to make it easier.


texts: Is a bank account sufficient to receive money in Bitcoins?

texts:
A few questions regarding bitcoin money transfer:

Can anyone transfer bitcoins into my bank account or do I need to have some bitcoin account for that?
Is it legal to receive bitcoins? Especially in India?
Why should one take payments in bitcoins? Is it a good idea or better avoid it?


texts: How do I extract my private keys from a protobuf wallet?

texts:
Recent changes to Andreas Schildbach's Bitcoin client for Android have removed the option to export private keys. This has been replaced by an option to back up the entire wallet. Unfortunately, the wallet data of the Schildbach client is stored in an arcane format called protobuf (short presumably for Protocol Buffers). The Schildbach client can restore a protobuf wallet from its AES-encoded backup file. But the protobuf wallet cannot be imported into a different Bitcoin client such as the Bitcoin Core (QT) client.

For emphasis, I'm aware of the command line method of decoding the back-ups created by Schildbach's client, which in the past allowed the private keys to be saved in AES encrypted format to /sdcard/Download. The following command worked in the past to produce a human readable copy of my Bitcoin private keys:

openssl enc -d -aes-256-cbc -a -in encrypted-wallet-keys -out decrypted-wallet-keys

This no longer works. The following command instead produces a non-AES-encrypted protobuf wallet.

openssl enc -d -aes-256-cbc -a -in bitcoin-wallet-backup-2014-07-19 -out bitcoin-wallet-backup-2014-07-19-decrypted

The -out file is not an ASCII copy of my private keys but a copy of the protobuf wallet used internally by the Schildbach Bitcoin client (found at /data/data/de.schildbach.wallet/files/wallet-protobuf).


texts: Signing a raw transaction with multiple inputs

texts:
So I am creating a simple P2PKH transaction and after I researched about this found few useful posts and answers here; I was able to successfully spend a a single P2PKH UTXO but it is really getting complicated when I try to spend transaction with multiple inputs. I have spent a day entirely on this.

All transactions are on Bitcoin Testnet.

Outputs I am redeeming:

  Tx Hash: 9742ed783bfec215ec6484d82dae20fba582229e54c49e06d662a91ead3f6a54
  Index: 0
  scriptPubKey: OP_DUP OP_HASH160 81f52d4061313b6f63549efc03f3df6cb6f0149e OP_EQUALVERIFY OP_CHECKSIG
  Tx Hash: 40dbd3c25073cb7222becead1eb9bb2195cf309cf5b24af559f3391168ec6318
  Index: 0
  scriptPubKey: OP_DUP OP_HASH160 81f52d4061313b6f63549efc03f3df6cb6f0149e OP_EQUALVERIFY OP_CHECKSIG

Now I read an answer from here that suggested if using multiple inputs, one should replace scriptSig for rest of inputs (the ones not being signed) to empty;  And I have tried these variations so far:

1. Replacing scriptSig for inputs with "00"

So only the input (UTXO) that is being signed will have its scriptPubKey, and other input(s) should have "00" in place.

  Serialized input #1 when signed:
  01000000
  02
  546a3fad1ea962d6069ec4549e2282a5fb20ae2dd88464ec15c2fe3b78ed4297
  00000000
  19
  76a91481F52D4061313B6F63549EFC03F3DF6CB6F0149E88ac
  ffffffff
  1863ec681139f359f54ab2f59c30cf9521bbb91eadcebe2272cb7350c2d3db40
  00000000
  00
  ffffffff
  01
  c0fb390000000000
  19
  76a914DD02C23FF4C3FFC6DA1C74B7EA5BCB0891B0E98288ac
  00000000
  01000000

and...

  Serialized input #2 when signed:
  01000000
  02
  546a3fad1ea962d6069ec4549e2282a5fb20ae2dd88464ec15c2fe3b78ed4297
  00000000
  00
  ffffffff
  1863ec681139f359f54ab2f59c30cf9521bbb91eadcebe2272cb7350c2d3db40
  00000000
  19
  76a914A17C43FE0E1F8E660B044C9538E2CEF4ABFDCED288ac
  ffffffff
  01
  c0fb390000000000
  19
  76a914DD02C23FF4C3FFC6DA1C74B7EA5BCB0891B0E98288ac
  00000000
  01000000

main transaction with both inputs signed: (signatures without 01 hash code type suffix and public keys are bold)

  01000000
  02
  546a3fad1ea962d6069ec4549e2282a5fb20ae2dd88464ec15c2fe3b78ed4297
  00000000
  6a
  4730440220E4A366646391B3CFB06C0C4B0343E678B560BE8A2D20418233DEE863986105E502207245C5BA3DB516E59B95764C1716F5B39850E20429F08B91389C4780CE45430E0121025F69830D2BA35D04CA9EFB3EA46AA2645BBBDCB592A189A539480657C9696137
  ffffffff
  1863ec681139f359f54ab2f59c30cf9521bbb91eadcebe2272cb7350c2d3db40
  00000000
  6a
  4730440220C41C498D0CA55E38FE85DD158FDE82BB451068124E2B3AA2391D861BA9281EDD0220165712ADF71B19DF525583D8F48B82DFF06B2E556C17A583F4D5C54E99412C6B0121039F9AF4A84A8D5C35DD7A5628F8C2DC1894C2B4BDD4815DAFFDCBC9102FE2BA26
  ffffffff
  01
  c0fb390000000000
  19
  76a914DD02C23FF4C3FFC6DA1C74B7EA5BCB0891B0E98288ac
  00000000

now decode raw transaction works but when trying to broadcast it, bitcoind gives these errors:

  mandatory-script-verify-flag-failed (Signature must be zero for failed
  CHECK(MULTI)SIG operation) (code 16)

or

  non-mandatory-script-verify-flag (Non-canonical DER signature) (code
  64)

I have tried different variants:

Replace scriptPubKey of inputs that are not being signed with just "00"
Replace scriptPubKey of inputs that are not being signed with just ""
Remove sequence number from inputs "ffffff"

but nothing seems to work. What am I doing wrong? Your help will be appreciated :)


texts: What is the average size of a bitcoin transaction?

texts:
I'm curious, since the inception of bitcoin, what is the average size (in bytes) of a bitcoin transaction?

To be clear, the easiest way to find this is not to take the size of the block-chain and divide it by the total number of transactions.  This is because there is a little overhead associated with block headers.  Transactions need to be accounted for one at a time for this averaging operation.

Has anyone taken the time to analyze this information and, if so, what were the results?  To be clear, I am interested in this answer as the data is stored in uncompressed-bytes.  I'm not interested in any textual (i.e. JSON) variation which might be used for network communication.


texts: Does a transaction with a lock time need more time to be confirmed?

texts:
I've made this transaction in the testnet:

https://testnet.blockexplorer.com/tx/2f18c646a2b2ee8ee1f295bb5a0f5cc51c5e820a123a14b0c0e170f9777518bb

It's a multisign tx with locktime. The locktime has expired and the tx is signed, but it isn't confirmed... Does somebody know why this tx isn't confirmed?

Thanks


texts: Is there a limit on number of transactions included in a block?

texts: As per my understanding, every transaction is included in a block and the difficulty to find a block gets adjusted such that one block is found for every 10 minutes. Is it the case that all transactions occurred in those 10 minutes included in that block? Is there a limit on number of transactions that can be included in a block?


texts: How to get xpub or mpk(bip32) for my bitcoin core wallet?

texts:
I m not getting any such option in bitcoin-core Ui and documentation
http://bitcoindaily.org/bitcoin-guides/bitcoin-core-tutorial/


texts: "private" agreement between two c-lightning nodes on channel closure fee

texts:
When i was at LNConf, one of the devs of c-lightning (IIRC) told me that there is a custom, manual way to agree between two nodes on channel closing fees.

Can anyone elaborate how this is possible? I am operator of two cln nodes, i would like to close channel between these nodes with minimum possible fee, because i am not in hurry.

Are there some side-effects of doing so?


texts: If an offline, never connected, Electrum wallet is lost, it can still be recovered?

texts:
I'm just making sure I understand this correctly, since I'm new to Bitcoin.

Lets say there is an Electrum wallet created, but on a machine which was never connected to the internet. This machine is then destroyed/lost/stops working.

The wallet, along with any funds which were sent to it, can still be recovered, as long as one has kept the seed? So this means that the private key is derived from the seed (this is what the deterministic aspect refers to?).


texts: Notify when new transaction is arrive in a bitcoin address

texts:
I have bitcoin full node on the server. I need to notify when new incoming transaction is arrive into a bitcoin address. Is there any RPC will help to achieve my goal ...

Any help is appreciable. Thank you


texts: Why do wallets use multiple private keys instead of one each?

texts: I am learning about Bitcoin and when I was about to export my private key from a single electrum wallet, I found that there  were in fact a lot more than one. Why is that so, don't you only need 1 private key to hold all bitcoins and manage them?


texts: undefined is not an object error when adding BIP39 to React Native

texts:
I have a React Native Project and it was worked correctly till I added bip39 package to the project. when i try to require bip39 in my component i get the below error.

undefined is not an object (evaluating 'superCtor.prototype')

inherits
inherits_browser.js:5:45
<unknown>
index.js:23:9
loadModuleImplementation
require.js:320:6
<unknown>
index.js:3:22
loadModuleImplementation
require.js:320:6
<unknown>
browser.js:3:17
loadModuleImplementation
require.js:320:6
<unknown>
index.js:2:24
loadModuleImplementation
require.js:320:6
<unknown>
BIP39.js:1:19
loadModuleImplementation
require.js:320:6
<unknown>
Mnemonic.js:5
loadModuleImplementation
require.js:320:6
<unknown>
App.js:5
loadModuleImplementation
require.js:320:6
<unknown>
index.js:7
loadModuleImplementation
require.js:320:6
guardedLoadModule
require.js:207:45
global code
<unknown file>:0

React Native Version 0.57.7

React Version 16.6.1

bip39 version 2.5.0


texts: what is the difference between a private pool or solo mining

texts: I would like to understand if there is a difference in resolving blocks with a private pool and solo mining, I understand that when solo mining you are given a block to resolve but within your private pool you may resolve various, this of course having several machines.


texts: get any transaction in p2p manner using bitcoinj

texts:
I'm pretty sure bitcoinj is capable of downloading any Bitcoin transaction from P2P nodes by broadcasting GetDataMessage because that's what it  does in the peer.downloadDependenciesInternal method.

I'm trying to find/implement a very simple method which would download a transaction with its inputs and outputs and the block in which it's included (if any) but, because of Guava asynchronous futures, I cannot figure it out.

Very simply, I would like to replace 3rd-party services like blockchain.info with something decentralized.


texts: I run a full node. Is there a desktop client to connect to this full node?

texts: I run a full node on my Raspberry Pi at home. I want a desktop wallet that uses this full node. Not interested in using remote-x or xpra or setting up an electrum server.


texts: How long does it take to receive bitcoins?

texts:
I bought 1.25 BTC but after 2 days I see nothing. What is wrong?
This is the transaction.

Also, I went to freebitcoins.appspot.com, since they claim thay they give for free 0.005 bitcoins per visitor. I did everything correct and the site said that I could see the transaction at freebitcoins.appspot.com/recent_sends.

But when I clicked on my transaction, it said: No such transaction

http://blockexplorer.com/tx/1eaf91e7d4ae3a8f976eaa346f4332d8bfd999d209ef899612e5b2995db0eeb9

Please guys tell me what is wrong?


texts: Why public Electrum servers serving on websocket (WS) are so rare?

texts:
Couldn't find a single one. Only TCP or TLS.
Am I looking in the wrong place? ( https://1209k.com/bitcoin-eye/ele.php?chain=btc )


texts:
There is very good answer here: How to redeem a basic Tx?
It works great.

But the algorithm is only for uncompressed addresses/keys, how can I change it to deal with compressed ones?

And the second question - how should I change the procedure to redeem several inputs?


texts: How often does temporary fork occur and how long does it last?

texts:
I was wondering, how often does temporary forks occur? They appear when there are two different blocks mined based on the same previous block (parent block), but what are chances for that? And if fork occurs, how long does it last (on average)? What is the moment in a chain when side branch gets discarded by the network, or when is the node certain that the branch he continues to mine on is really the longest one (following the longest chain rule)?
Thank you guys!!


texts: What should I do about the March 12th 2013 blockchain fork?

texts: Reddit/r/bitcoin is flooding with news that the Bitcoin blockchain has forked, in that versions 0.7 and 0.8 are accepting different blockchains. What does this mean for the users?


texts: Time series data for issues listed on the (now defunct) GLBSE

texts:
I would like to get the following data for every issue ever listed on GLBSE:

Time series of closing prices since IPO to de-listing (or closing of GLBSE),
Date and quantity of initial and secondary offerings, and
Dividend history.

The motivation behind this is constructing a total return index for the GLBSE.

How can I get these data?


texts: When does a crypto exchange write to a blockchain?

texts:
From my understanding, when dealing with an exchange you first transfer your currency to the exchange's address. The exchange then pools the currency of its participants.

When transactions then take place across the exchange, the exchange doesn't write to the underlying blockchain, but records all these transaction by changing their records of ownership in their own internal database.

When you withdraw your funds, you then retrieve your currency back to your own wallet.

Does this mean an exchange will only write to the blockchain when you transfer currency to or withdraw money from the exchange?


texts: What stops people attacking my new coin?

texts:
Say I just made a new altcoin.
I mined it for a few days at some reasanoble difficulty - 2000 for example.
I got to the 10 000th block and I am happy with my premine and network.

Then, an attacker downloads my client and without connecting to the network, starts mining with some huge hashing power.
So for 24 hours, he is at block 12 000th with difficulty of 5000.

Then, he connects to my network.
Wouldn't that make all my nodes sync with his network?
This way I would lose my premine, wouldn't I?

Is that the case?
Can I prevent the attack?


texts: What are the privacy techniques that used with Litecoin? and what are the differences between Bitcoin and Litecoin in privacy techniques?


texts: Does Bitcoin account for deleted bitcoins over time?

texts:
I'm sure that this question has been asked before, but I just can't seem to find it.

If there is a limit of 21 million coins to be mined, then what happens if Bitcoin wallets get deleted? Will there still be some percentage of mining that occurs to make up for the lost coins?


texts: Are HD wallets, with multiple hierarchies, supported across all crypto-currencies?

texts:
Suppose I want to create an arbitrary tree deriving from one master secret, with an arbitrary structure, with some branches being arbitrary different crypto-currencies (e.g. BTC/ETH/XRP/...).

Is this always possible? Are there any currencies that won't be supported by such a private key generation scheme?


texts: Litecoin mining 10 times slower than a couple of days ago

texts:
I have a 5850, and have been mining with it for about a week.

With GuiMiner I can mine bitcoins at about 275Mhash/s.  This has not changed.

A couple of days ago I setup Litecoin mining and it was working at about 350Khash/s, which at the time was about the same profit as Bitcoin.

But now when I mine litecoins I'm only getting 35 khash/s.

I'm getting the same speed with CGMiner or Reaper.  I just started the exact same setup I had last week and I'm getting the crappy result.  I've been messing with settings and config, but no change.

I have rebooted, no change.  I can change back to Bitcoins anytime and get 275Mhash/s with CGMiner, but when I change CGMiner to Scrypt mining it drops to 10% what it should be getting.

I can't think of anything that would cause this.  Any thoughts?

Scrypt CGMiner mining:
http://puu.sh/2d7Mp

Bitcoin CGMiner mining:
http://puu.sh/2d7NW

Current CGminer command:
cgminer --scrypt -o x -u Liquid5n0w.1 -p x --intensity 12 --worksize 256 -g 1 --lookup-gap 2 --thread-concurrency 7200  --fix-protocol


texts: Get scripthash for known scriptPubKey in PHP

texts:
I have to query addresses in ElectrumX server. How do I generate scripthash for a known scriptPubKey in PHP?

Example address:

array (
  'isvalid' => true,
  'address' => '1MUz4VMYui5qY1mxUiG8BQ1Luv6tqkvaiL',
  'scriptPubKey' => '76a914e0ad60c897901128662623c500a4a6079e99cd3e88ac',
  'isscript' => false,
  'iswitness' => false,
)

I tried:

hash('sha256', hex2bin('76a914e0ad60c897901128662623c500a4a6079e99cd3e88ac'))

But it seems to be wrong.


texts: If I send a BTC to an offline cold storage, does the transaction in the blockchain appear when i send it or when i receive it or not at all?

texts: If I send a BTC from my hot or exchange wallet to my cold storage does it has to pass the blockchain or can the blockchain be bypassed? If it has to pass the blockchain, when does it appear in the block explorer? when I send it? when I receive it (the cold storage comes online)? or not at all?


texts: Is there any good reason to buy Bitcoins?

texts: I've read the introduction to bitcoins. But the main question remains: what reasons could push me to buy bitcoins today?


texts: Is there a way to buy bitcoin immediately?

texts:
I want to use PHP to write a script to buy bitcoins and my bitcoin balance will be updated immediately (i'm NOT in US).

For example, I use my credit cart to purchase bitcoins. less than 1 min later, I can see my new bitcoins in my address.

As I know, normally, it will take few hours / days to get bitcoin from some bitcoin sellers. It is not safe to get bitcoin immediately because banks allow charge back.

So is there a safe, automatic and immediate way to get / buy bitcoins?


texts:
i dont remeber my passphrase of my  bitcoincore wallet.
I try with an hex editor but i don’t know wich string i have to search.
how can i recover it?
Thanks to all can help me.
I’ve followed some post in various forums but I find only instructions for various wallet but nothing for bitcoincore.
I know that is possible to find a pass phrase with an hex editor but I don’t know what searching for


texts: Is it Possible to Program AntMiner S9 or Other ASIC Miners?

texts:
Is it possible to program the AntMiner S9 or other ASIC miners?

For example, let's say I only want it to try nonces from 1 to 1 million (instead of all 4 billion possibilities) would it be possible to somehow modify the software on the machine to do this? (please don't ask me why I want to do this, I just want to know if something like this is possible)

If it's possible, what programming language would I use?

Finally, would doing this (significantly) reduce the hash rate of the miner?


texts: Multiple outputs and different amounts on blockchain explorer when I sent BTC from Crypto.com to Coinbase

texts:
So I sent BTC from my Crypto.com wallet to my Coinbase wallet.
I then went on the blockchain explorer to view the transaction and I am seeing an input that is not my address and various outputs which include my address as well as other addresses that do not belong to me.
The unknown addresses also have different amounts too.
why am I seeing various outputs with different addresses and amounts?
Thank you!


texts: Is there a chance to return all of the lost money invested when the chart goes back up?

texts:
Let say, for example, I invested $3 to buy 21 TRX (Tron Tokens), usually a token under Ethereum platform but still working the same as other altcoins when the value goes high, where the price is around approximately $0.14 per TRX. A week later, the token price is raised to $0.21. the following days later it dropped back to $0.14 and later $0.13 which is below the total amount of money I've invested.

Here's the worst case scenario: the price of TRX dropped to $0.001 after several days and definitely all of my investments are gone (30 TRX is equivalent of $0 instead of higher than $3 in return). Take note that this token/altcoin is legit and while taking better changes to improve while the investors are still counting on it. Now, the price of 1 TRX is now suddenly jumped to $1 after another few days.

The question is this: is my $3 invested after couple of weeks will be dropped to $0 and still $0 even after when the price of token drops to $0.001 and raised it back to $1 or not?


texts: What is the estimated ROI for someone who bought in before 2010?

texts: As the title asks, what kind of profits were available for those people who were lucky enough to have found out about Bitcoin prior to 2010? Or when it began?


texts: Is there an implemented color coin demo for bitcoin?

texts: Is there an implementation of color coins on the bitcoin blockchain yet? a demo would be great.


texts:
Several months ago I've stumbled an interesting question about the Ripple system: How does Ripple solve the double-spend problem?

Specifically about how double-spending is solved in Ripple. As you can see only @David Schwartz replied to my comments and only he was able to give an answer, given that I think he works for Ripple.

But if he's right, this would be revolutionary in a way, since Bitcoin electricity wasting mining could be replaced by this system.

In any case, my question is: can Bitcoin mining be replaced by a Ripple sort of system? How would that work?


texts: Explicit message length in Bitcoin Signed message

texts:
the message format is:

length(prefix),prefix,length(message),message
with prefix="Bitcoin Signed Message:\n"

now I am wondering why the length(message) in the middle is needed as it should be able to just calculate it from total_length-prefix_length

Some context here: https://github.com/ethereum/EIPs/pull/683#issuecomment-358460381


texts: I need help figuring out what happened with my BFGminer overnight

texts: I'm a newbie to crypto and was experimenting with usb erupters because I was getting into ETH mining with my rig and wanted to test it on something less risky. I ran ck pool for my USB erupter just to see and monitor its temps over a course of time. I ended up getting a message from the pool stating: accepted 000593e0 (usb erupter name) Diff 11.7/10k. I have no idea what this means but my efficiency rose to 12.66 and my accepted shares are at 1. Back of my mind I'm wondering if I lucked out and mining a block but I check my coinbase wallet and I see no BTC. So, im wondering what this means.


texts: Predict multi signature transaction size

texts:
I was looking for answer everywhere.
Basically is there any way of calculate multi-sig transaction size when the transaction is creating, before the signing procedure? I was trying to find any pattern for that, with no results.

Informations I have:

num of inputs;
num of outputs;
num of required signatures

I will appreciate any clue to solve this problem.


texts: Transferred bitcoin to an address - they are gone - what can I find out?

texts:
I was transferring some bitcoin between online wallets to sell some.

I must have been distracted or something, I was transferring to a coinbase account. It has all been confirmed but the address it says it went to doesn't correspond to any coinbase addresses (not bitcoin, litecoin or ether).

I may have done something stupid here - but I'd like to find out what happened. I thought I might have entered an Ether address by accident - but as I say it doesn't correspond to my ether address listed on coinbase - + I read that the network would reject it anyway because it know's it's not a bitcoin address.

I have the to address - how can I research this further? I've found nothing on Google of help. thx.

The to address:
1ACLteUzuXTYHV5v9nsoEk648hK8DShb4B


texts: I am going to buy bitcoins for the first time from a seller on LocalBitcoins. Please guide me.

texts:
I am going to buy bitcoins for the first time from a seller on LocalBitcoins. He says that funds can be transferred via internet banking. He seems to have good feedback, 9+ reviews but I am kind of nervous. What exact steps should be followed for a smooth transaction?
My plan is:

Send him my wallet address, and then wait for him to transfer the bitcoins.
Upon successful transaction, I send him the required amount through an online bank transaction.
??
Profit

I hope I am doing this right. Please advise.


texts: Who needs a copy of the entire blockchain these days?

texts:
As discussed in this question there is a news report today saying that researchers have found illicit files and information stored in the blockchain.

In today's Bitcoin world, who needs the full block chain?  With mining pools and online wallets looking like the norm (is this true?), do many people at all download the entire chain, or at least large portions of it?  I'm sure that researchers will download it in full, but what are the other use cases?  Does it extend at all to any casual users?


texts: If miners are creating their own mining algorithms or using something standard

texts:
From this:

  the arrival of a new block has special significance for a mining node. The competition among miners effectively ends with the propagation of a new block that acts as an announcement of a winner. To miners, receiving a valid new block means someone else won the competition and they lost. However, the end of one round of a competition is also the beginning of the next round. The new block is not just a checkered flag, marking the end of the race; it is also the starting pistol in the race for the next block.

So I just wanted to clarify because I don't think I've seen it written down anywhere, that it's in a miners best interest to create their own algorithms to solve the computational challenges involved in mining. It's not as if every miner gets a standard algorithm and runs that. Please correct me if I'm wrong.


texts: Location of blockchain locally on different platforms, and structure of blockchain file?

texts:
I just downloaded Bitcoin-QT, and torrented a snapshot of the block chain that is a couple weeks old. I put the bootstrap.dat in ~/Library/Application Support/Bitcoin and started up the app. Right now it is "Importing blocks from disk". Where do the blocks goes once they've been imported? A friend of mine says that the Bitcoin app makes a Merkle tree out of the blocks in the block chain. How is this stored? I want to write a program that takes snapshots of the block chain every couple hours. It would be much better if I could just update a copy of the block chain as needed instead of making an entire new copy and deleting the old copy.

How do I make a bootstrap.dat out of the blkXXXXX.dat files?


texts: Is it possible to use a BTC full node (running on linux) to query an address and either see all of those address transactions or to get a list of their UTXO's so you can calculate a balance and see how much has been spent? If not, how do sites like BitRef accomplish this task? Simply put in BTC address and it shows all the transactions and the balance of the wallet in just a few seconds? Do they have some sort of DB they leverage in addition to the blockchain?


texts:
People keep saying that proof of work functions like scrypt prevent ASICs from working because of large memory requirements.

What's stopping ASIC designers from simply building ones that have lots of memory?


texts:
https://bitcoincore.org/en/doc/0.21.0/rpc/wallet/sendmany/
What is the limit on the number of "transactions" you can make inside one "sendmany" call/transaction? 10? 50? 500? Thousands? Tens of thousands? Unlimited?
What happens if that (presumed, undocumented) limit is reached? Will the client not allow it or will it allow it and then sit there in limbo forever or for a long time?


texts:
I am after a couple of fans for my A2 as the bearings have gone.

From what i can see and have measured, they are a uncommon size at 105/106mm. Is this correct?

Any suggestions on replacements?

Thanks


texts: Anyone could teach me more detail about version prefix

texts:
In this post Does the version prefix of an address force the type of transactions the address may treat?, I saw "the version byte doesn't actually appear in the final transaction."
I don't understand why? Could anyone can help to tell more detail about that?


texts: What is the point of mining the Bitcoin and thus issuing new Bitcoins over the span of some time versus simply issuing all 21 million coins at once?


texts: One can find lots of logos on the internet that say "Bitcoin accepted here".  In some contexts, including, but not limited to, selling things over the internet, it seems appropriate to omit that last word and just say "Bitcoin accepted".  Are there some of those?


texts: Are there any tutorials with examples on Bitcoin Script: from basics to complex scripts?


texts: What are the differences between Bitcoin and Libra?

texts:
Recently, Facebook announced to launch a  crypto currency called "Libra". Libra is managed by associations under the name "Libra Association", see https://libra.org/en-US/association/.

What are the differences between the Bitcoin and Libra algorithms and protocol?


texts: What if some attacker forks blockchain from height 1 with a constant difficulty 1?

texts:
I've been reading Satoshi's paper recently. There's one thing I cannot think through.

That is because the target will limit the block production speed to 2016 blocks per two weeks on average no matter how high the hashrate gets. What if the attacker forks the blockchain from height 1 with a constant difficulty 1 and produces exactly 2016 blocks per two weeks (just in timestamps, not in real time). I think it will be very easy with such low difficulty to catch up current blockchain's length, and eventually surpass. According to the longest blockchain concensus, will the fake blockchain replace the current one?

I would be grateful if someone could clear up my confusion.


texts: How to send bitcoin without any fees to different btc address?

texts:
Now I am using regular client wallet to spend my btc amount. but it charges me miner fee, sometime it pretty high. I dont want to pay fees anymore.

My friend heard about a way to send btc without any fees. In this point my questions are:

what is the demerits if I want to send btc without fees?
And Finally, How could I send btc to different address without paying any fees?


texts: Bitcoin-cli how to get balance of a wallet on different node?

texts:
I am making a bitcoin mobile application, and I an trying to get the balance of a wallet that is on the mobile phone, from a daemon that is running on a separate node. The mobile wallet is connected to this node and can use any of the CLI commands such as getinfo getbalance etc.

What CLI commands do I pass to the daemon to give me the balance of the wallet on my mobile application?


texts: Bitcoin blockchain search algorithm and consistency policy

texts:
The blockchain looks like a double linked list, and all the transactions are stored into each block. What kind of algorithm does bitcoin use to find a specific transaction efficiently, since the blockchain is growing bigger and bigger?

The bitcoin network use its compute power to keep data consistency, if we simplify this model(write once read many, no update, no cheat) and use its consistency policy into the geographically distributed file system, does that work?


texts: What is the public key used to generate the Genesis block?

texts:
I'm trying to create and build a working fork of Bitcoin -- in order to understand how it works at the source code level. I see a lot of articles explaining how to create altcoins but they are not very helpful for the learning purpose as they skip a lot of details and tend to tell you what to do without explaining why.

Regarding this question, I couldn't find any article/document even remotely mentioning anything about the public key used for generating the genesis block -- I believe this is an important things to know, at least because it's been used to generate the genesis block of Bitcoin. Looking at the source code:

Bitcoin 0.1.5 - main.cpp @1490:

  txNew.vout[0].scriptPubKey = CScript() << CBigNum("0x5F1DF16B2B704C8A578D0BBAF74D385CDE12C11EE50455F3C438EF4C3FBCF649B6DE611FEAE06279A60939E028A8D65C10B73071A6F16719274855FEB0FD8A6704") << OP_CHECKSIG;

Bitcoin 0.8.0 main.cpp @2715

  txNew.vout[0].scriptPubKey = CScript() << ParseHex("04678afdb0fe5548271967f1a67130b7105cd6a828e03909a67962e0ea1f61deb649f6bc3f4cef38c4f35504e51ec112de5c384df7ba0b8d578a4c702b6bf11d5f") << OP_CHECKSIG;

These two public keys are same. First one appeared in the very first version of Bitcoin -- as far as I can see in the Github repo. Second one is the latest usage before it being totally removed from the source code.

My questions are:

What is this public key? Is this [supposedly] Satoshi's personal public key or just a random key generated for the sake of generating the genesis block?
Is there any other application for this public key or it's only useful when generating the genesis block? e.g. signing transactions? verifying the integrity of the mined blocks?
There are different formats used for Public/Private key pairs. What is  the format used for this specific key? Is there any built-in API/utility inside the Bitcoin source that could be used for generating or testing the validity of the key?
What are the consequences of using a broken/invalid public key at this stage? Given the fact that the genesis block is unspendable.


texts: The best JavaScript libraries supporting Bitcoin Core?

texts: I have downloaded and installed Bitcoin full node on my Linux server and I'd like to start working with the bitcoin core to create wallet, addresses, and transactions. What is the best JS libraries available to facilitate using all the necessary methods in this regard?


texts: What drives the price of bitcoin, in other words, what makes it go up or down?

texts: I am interested in knowing what kind of events and news have a direct impact on the bitcoin prices besides the raw supply and demand.


texts: Can a miner not find a share in his work unit?

texts:
I understand that a mining pool operator distribute work units at it miners.

Is it possible that a miner can find no share in his work unit?

If is the case, this mean a miner can work for nothing?


texts:
"Distributed" means operating on more than one devices which dont share physical memory and perform their task (which might be storage or computation) to perform one single task (which in our case might be to have same copy of ledger)

"Consensus" means when everyone is on the same page.

So,"Distributed Consensus" means we want all the different devices on the network which dont have a shared memory and communicate by message passing mechanism to have same copy of ledger. Is that correct ?


texts:
Is the purpose of difficulty only to manage the rate of a cryptocurrency's creation, or should difficulty also increase over time to compensate for Moore's Law for a consistent level of security?

Would a cryptocurrency with an extremely short difficulty time of < 5 seconds, even 1 second, be secure?


texts: How to get transaction fee from raw transaction?

texts:
I know that we have to calc inputs total minus outputs to get transaction fee, but using getrawtrasnaction RPC call, inputs values are not attached. how is it possible to get transaction fee?

Array
(
    [txid] => 318abc03cfa52c996b01d6ff10faf86447341d78acdf849026dd4c22ebd56cab
    [hash] => 318abc03cfa52c996b01d6ff10faf86447341d78acdf849026dd4c22ebd56cab
    [version] => 2
    [size] => 226
    [vsize] => 226
    [locktime] => 0
    [vin] => Array
        (
            [0] => Array
                (
                    [txid] => 71c6f340ef5f4688136e8b308393ff74a89b4bf780bf0e3c3611fa34dc858c07
                    [vout] => 0
                    [scriptSig] => Array
                        (
                            [asm] => 30450221009c305ffb2f04517ba1f422f22f0eded5afb855f0ee8cdd2634259774dfb0846b022019e05a9d25f21e808a0be320e3956a1e6fcb57cc4d725404db0bbab0ced78a88[ALL] 0221b96462902141e297804981ebc5465e475ebf0f4f4d7a4e558edc4856b33e75
                            [hex] => 4830450221009c305ffb2f04517ba1f422f22f0eded5afb855f0ee8cdd2634259774dfb0846b022019e05a9d25f21e808a0be320e3956a1e6fcb57cc4d725404db0bbab0ced78a8801210221b96462902141e297804981ebc5465e475ebf0f4f4d7a4e558edc4856b33e75
                        )

                    [sequence] => 4294967295
                )

        )

    [vout] => Array
        (
            [0] => Array
                (
                    [value] => 0.01
                    [n] => 0
                    [scriptPubKey] => Array
                        (
                            [asm] => OP_DUP OP_HASH160 e673381ba3ce7fa72520a09ee4e3ad68cd5d6528 OP_EQUALVERIFY OP_CHECKSIG
                            [hex] => 76a914e673381ba3ce7fa72520a09ee4e3ad68cd5d652888ac
                            [reqSigs] => 1
                            [type] => pubkeyhash
                            [addresses] => Array
                                (
                                    [0] => n2XTjk57QJgjevmYb75tJHy7AJGGeoJv2e
                                )

                        )

                )

            [1] => Array
                (
                    [value] => 0.089981
                    [n] => 1
                    [scriptPubKey] => Array
                        (
                            [asm] => OP_DUP OP_HASH160 108e2c445972c2561d8cff8ee487cfe6e054ab59 OP_EQUALVERIFY OP_CHECKSIG
                            [hex] => 76a914108e2c445972c2561d8cff8ee487cfe6e054ab5988ac
                            [reqSigs] => 1
                            [type] => pubkeyhash
                            [addresses] => Array
                                (
                                    [0] => mh2VRUG7BA8Rutz9tqTuhinqZxRo3QinGi
                                )

                        )

                )

        )

    [hex] => 0200000001078c85dc34fa11363c0ebf80f74b9ba874ff9383308b6e1388465fef40f3c671000000006b4830450221009c305ffb2f04517ba1f422f22f0eded5afb855f0ee8cdd2634259774dfb0846b022019e05a9d25f21e808a0be320e3956a1e6fcb57cc4d725404db0bbab0ced78a8801210221b96462902141e297804981ebc5465e475ebf0f4f4d7a4e558edc4856b33e75ffffffff0240420f00000000001976a914e673381ba3ce7fa72520a09ee4e3ad68cd5d652888acd44c8900000000001976a914108e2c445972c2561d8cff8ee487cfe6e054ab5988ac00000000
    [blockhash] => eb31cb0c8de0e8b3219537e9304ee7d09d5dc7092ef17caed470b9a1aed2485e
    [confirmations] => 2269
    [time] => 1522693379
    [blocktime] => 1522693379
)


texts: What does the Bitcoin Core wallet backup do?

texts:
I set a password to encrypt my wallet, all good.  But I can't seem to backup my wallet.  I try and nothing happens.
Does the backup function give me keys or the seed words?


texts:
Based on a certain amount of addresses, is it possible to find out how many bitcoins a specific wallet includes/owns?

E.g. I have a blockchain.info wallet. If I create 1000 bitcoin addresses, fill them with 1 bitcoin each. The blockchain.info wallet, will show me the total  balance of 1000 bitcoins on my wallet.
If I share one of this addresses with someone, will he be able to find out that I have a wallet with an overall amount of 1000 bitcoins?


texts: Can one wallet send/receive bitcoins from/to multiple sources simultaneously?

texts:
Let's say for example I put my public bitcoin address on a website for donations and multiple people for around the world deposit bitcoins simultaneously to that same wallet:

Will all deposit transactions be valid on the bitcoin network or might some transactions "overwrite" the other?
While receiving bitcoins from someone (not yet a verified transaction on the network), can I withdraw or pay bitcoins using the same wallet given the amount only include previous bitcoins and does include the new deposit?


texts: How can I speed up payments to my c-lightning server?

texts:
I setup a BTCPayServer on an AWS instance with a pruned bitcoind and c-lightning. I setup an inbound channel from Bitrefill and everything does work but I'm disappointed about the performance.
Using a Phoenix wallet it consistently takes 16s for payments to get confirmed while another BTCPayServer a friend configured and runs at home on his RPi which I don't have a direct channel to neither takes 8s.
The transaction details tell a slightly different story. According to those, paying my server took 11, 4, 4 and 4s while paying the other server took 5s. I assume that is measuring time only after some costly hand-shaking and routing but the time between hitting "pay" and the website and my phone displaying simultaneously "success" is much longer. Can I decrease that time somehow? Would I need more inbound channels, so my phone finds a faster one? Is there some option to speed things up? Is dual core the issue? ...


texts:
Is the 51% attack the only technical reason no country will adopt Bitcoin as a state currency?
Lets suppose a country with GDP size less than 300 Billion USD adopt the Bitcoin as an official currency. It will be very easy to crush or take control of state currency if a country like US or China invest to run 51% of mining pool.


texts: Which major/noteworthy BIPs, Soft-Forks and Hard Forks have there been since the Summer of 2017 (after SegWit/Bitcoin Cash)?

texts:
There are many lists of major forks however most of them end after SegWit. The full list of BIPs is extensive. Which noteworthy BIPs, Soft Forks and Hard Forks have there been since SegWit and Bitcoin Cash (i.e. After Summer of 2017)?

Bitmex List
Book List
Full List of BIPS


texts:
I have breadwallet on my smartphone and Electrum as Desktop Wallet. Can I share the same account on both? How can I do?

And, is it a good thing to do? Or is it preferred to have some bitcoins on one wallet and some others on the other one?

Thank you!


texts: Do all block have to be verified every time a new block is broadcasted?

texts:
I did a presentation for my office and during the presentation I was asked a question that I was not prepared for. It's a more technical question from my perspective, but someone here might already know the answer.

We know that every 10 min a block is created. And a new block has information of the previous block along with its findings and submitted to the net to be verified.

My question is when a pool or an individual miner is doing the verification, do they verify all the transactions starting from Genesis block till the most recent one?

And this goes on after each block is verified. Meaning every new block that needs verification needs to be verified along with all the previous transactions starting from the Genesis block?


texts: Does the official Bitcoin version 0.8. client still download the whole blockchain?

texts:
The release notes for version 0.8 of the "Satoshi" client say

  "Bloom filter" support in the network protocol for sending only relevant transactions to lightweight clients.

Is this an optional feature or on by default? Does this mean that the client will no longer download the whole blockchain? What is a relevant transaction? Is it only transactions related to keys in my wallet?
Does that mean that I can no longer keep the machine that downloads the blockchain separate from the machine that hosts my wallet (and that I keep offline, copying over the blockchain manually by USB). If so, is there an option to get the old behaviour?


texts: Java bitcoinj: semantics of 'decompress' on encrypted key

texts:
Calling the decompress method on an encrypted ECKey object yields an ECKey object which has no private key (only public). I personally would have expected to get the same encrypted key in uncompressed format (i.e. nothing changes except the encoding of the public elliptic curve point). Can anyone comment on whether there is a good reason for the API to be the way it is, or whether this is most likely an oversight? I attach a snippet for illustration:

import org.bitcoinj.core.ECKey;
import org.bitcoinj.crypto.KeyCrypter;
import org.bitcoinj.crypto.KeyCrypterScrypt;

import org.spongycastle.crypto.params.KeyParameter;

public class Test {
  public static void main(String[] args){
    ECKey k1 = new ECKey(); // some random (compressed) key

    // encrypting k1
    KeyCrypter crypter = new KeyCrypterScrypt();
    KeyParameter aesKey = crypter.deriveKey("some arbitrary passphrase");
    ECKey k2 = k1.encrypt(crypter, aesKey);

    // a few checks
    System.out.println(k2.isCompressed()); // true
    System.out.println(k2.isEncrypted());  // true
    System.out.println(k2.isPubKeyOnly()); // true  (private key not available)
    System.out.println(k2.isWatching());   // false (but it has a private key)

    // now decompressing encrypted key
    ECKey k3 = k2.decompress();

    // a few more checks
    System.out.println(k3.isCompressed()); // false
    System.out.println(k3.isEncrypted());  // false (hmmm, really?)
    System.out.println(k3.isPubKeyOnly()); // true  (private key not available)
    System.out.println(k3.isWatching());   // true  (because there is none)

    // Esentially same public key, but third has leading byte 0x04 (uncompressed)
    System.out.println(k1.getPublicKeyAsHex());  // 03585c156c1449155420 ...
    System.out.println(k2.getPublicKeyAsHex());  // 03585c156c1449155420 ...
    System.out.println(k3.getPublicKeyAsHex());  // 04585c156c1449155420 ...
  }
}


texts: Trying to access my BTC from Bitcoin-Qt wallet that is out of sync

texts:
I bought BTC and sent them straight to my Bitcoin-QT wallet. Now opened my wallet (ver. 4.8.3) and it says ~29000 blocks remaining to synchronize but this is not happening even though I have 14 active connections.

I have tried accessing my Private Key through both Help>DebugWindow>Console and the version using CMD bitcoind dumpprivkey etc with both returning the error message "Safe mode: Warning: Displayed transactions may not be correct! You may need to upgrade, or other nodes may need to upgrade. (code -2)"

I don't have an encrypted wallet and just want to have access to my money.


texts: How do my bitcoin peers become diversified from the set of stable nodes?

texts:
I read through a variety of threads on initial peer discovery like How do Bitcoin clients find each other? and How does the bitcoin client make the initial connection to the bitcoin network? and they all say that if it is your first time connecting then you connect to the DNS seeds which give you a list of hard-coded stable nodes. If it is not my first time connecting, then I connect to whoever I was connected to before.

It is not clear to me why every client would not everyone always connect to these same set stable nodes every time (after the first connection, they are now in my dat file and I always use them)? By what process do my peers become diversified from the hard-coded stable nodes?