texts: Bitsqaure: Can I contact arbitrator before time limit?

texts:
So I started my first transaction on BitSquare. I waited for about a day for block confirmations. Finally got the message saying that I could go through with payment to the bitcoin seller using payment method: ClearXchange.

However, when I went to clearxchange and input the seller's info, the service says that he is not eligible to receive money with clearxchange. I would like to be able to contact the arbitrator to let him know of the situation, but according to the system, I have to wait for the maximum allowed transaction time (or half of it) to pass and then I and the seller will get the change to open a dispute.

I am concerned that if the seller gets to open dispute first for not receiving payment and contact the arbitrator, that I will loose my deposit even though he is the one not properly setup to receive payment. I would like to do 'cmd+o' but bitsquare says that I should only do that if there is a software bug!

Do I have no choice but to wait? Are there any other options open to me for contacting the arbitrator ASAP? Could I do 'cmd+o' and state a "lack of ability to comunicate" as a software bug? What's the appropriate course of action here?

Thank you


texts:
I always expected the LTC and BTC exchange rate to show synchronous tops/bottoms, but to my surprise LTC seems to remains stable during BTC crashes (and vice versa).

Is this because I'm a novice at chart-analysis, or is there really little correlation?


texts: Can I use one graphics card for games and one for Bitcoin mining, without losing performance?

texts:
I have a GTX660 right now, but I bought an R9 290x recently. I was wondering if I can leave both in my pc and use one (the GTX660) for Bitcoin mining and one (the R9 290x) for everything else (mostly games).

Is this even possible?
Will it decrease gaming performance to run a miner on a separate card?

The rest of my specs:
i7 3820 @ 3.60 GHz
16GB DDR3 RAM @ 1333MHz
Asus 2011 P9X79 Pro
Windows 8 pro

I bought the new card for gaming, but if it would be possible to do this with my old card without losing performance that would be great.


texts:
Suppose I have 2 wallets and 1 bitcoin and I write a program to make transfers of 1 satoshi from one wallet into the other.

Now suppose I have 100 bitcoins. Wouldn't that saturate the network?


texts: How can I mine a block, in C#, on a new Testnet network where no other miners exist?

texts:
I want to demonstrate how to use NBitcoin or the most simple C# function to

collect transactions for use in a block
then sign that block
submit it into the Bitcoin-QT network client on the RPC port?

I want to demonstrate how this is done on low powered devices.


texts:
I am using Bitcoin JSON RPC 14 version so how can I use sendFrom
  command in the case of fee inclusive.


texts: Can I use bitcoin-cli estimatefee API for Segwit?

texts:
I'm using estimatefee API to calculate transaction fee for Non-Segwit.

I'm using this formula now.

size = 180 * len(inputs) * 34 * len(outputs) + 10
necessary_fee = int(size / 1000 * fee_per_kb)

Example (1 inputs, 2 outputs. They are all p2pkh)

fee_per_kb = 25000 // result of bitcoin-cli estimatefee
size = 180 * 1 * 34 * 2 + 10
necessary_fee = int(size / 1000 * 25000)

// necessary_fee => 306250 satoshi

Now I need to calculate fee for Segwit. My question is that can I use bitcoin-cli estimatefee for weight? My expectation is this like below.

fee_per_kb = 25000 // result of bitcoin-cli estimatefee
virtual_size = (Something calculation logic including segwit discount)
necessary_fee = int(virtual_size / 1000 * 25000)


texts: Bitcoind Keypool Best Practices For Web App

texts:
I'm creating a web application where many, many transactions will take place in a day. I have the bitcoin daemon running on a VPS and talking to my web app via JSON-RPC.

The users on my website will be generating many different addresses and sending many different bitcoins to these addresses (much more than the 100 keys by default in the keypool).

Should I simply set the keypool size to be something like 100,000 (or the max number of addresses generated per day) then perform a daily backup? Or what other method is the best when dealing with a very large amount of address generations?


texts: Bitcoin core trying to sign a transaction loaded from psbt file, but getting "could not sign any more inputs" error

texts:
I am trying to sign a transaction loaded from psbt file, but I'm getting could not sign any more inputs error.
I did it successfully on the first try. However I cannot do it any more now.
I changed my passphrase of bitcoin-core before I did the second try. Does it matter?


texts: The AsicBoost paper by Timo Hanke and Sergio Demian Lerner describes a way of increasing ASIC performance by 20%. It's a bit sparse on the details, though. What are they optimizing?


texts: Why can you mine so much more of other cryptocurrencies with a lower hash rate?

texts: I have been researching bitcoin mining and one thing has stumped me. Why is it that you can you mine so much more of other cryptocurrencies with a lower hash rate? I've looked on cryptocurrency calculators and it says that 1 TH/s for Ethereum makes a profit of about $2M per month, but only $53 per month with bitcoin. If your hardware is capable of producing a high hashrate, why not mine a smaller cryptocurrency and exchange it right away?


texts: In which cases could I find funds locked in a failed route?

texts:
I received an invoice from node Z and my node (A) suggests me 4 possible routes.

If the first two routes fail, are there cases in which funds can get stuck in one of these routes until the HTLC expires?

Which are these cases? Are they avoidable?

If I try the routes with a failed hash can I avoid to have my funds locked in a failed attempt (or is it better to test routes with a few millisatoshis)?


texts: What are the perceived advantages of bitcoin as a means of exchange?

texts: There are lots of ways to send money - western union, paypal, bank wire, etc that are more established and fairly quick. What are the advantages of using bitcoin from a bitcoin-proponent's point of view?


texts: How to split BTG in electrum and send to new ledger nano s wallet

texts:
I currently have all my BTC on my electrum wallet, and I had them before the BTG fork. I haven't done anything regarding splitting since the fork, but now that I have the ledger nano s, I want to move my BTC from electrum to the ledger.

Now I am in no way familiar with a) splitting BTC/BTG and b) replay attacks, but I am afraid of losing any coins in the process. As I understand, I shall do the following:

Make a regular BTC transaction to move all BTC from electrum to the ledger nano s BTC address
Get a BTG wallet, and import electrum's private keys in it. Then, I have 'claimed' the BTG
Make a regular BTG transaction and move the BTG from the BTG wallet to the ledger nano s BTG address

Is this correct? Is there any chance of losing anything with this process?


texts: Can anyone give me some help editing the Abe html?

texts:
I've got Abe running, but would really like to get the page looking nicer. I've managed to change the logo, but would like to change the title and change some colours and fonts, maybe add some more text.

I know this HTML is generated on the fly, from abe.py? I've tried editing that, but it doesn't seem to effect my page at all.


texts: Is there an API that provides information on the consensus algorithm of altcoins?

texts:
Is there an API that offers information on the consensus algorithm of altcoins? Something like examplewebsite.org/api?name=steem

{
...
"consensus":"DPoS",
...
}


texts: How does consensus protect from lying about transactions?

texts:
I'm really new to the whole concept of blockchain.

I do understand how consensus protects from changing past blocks and allows to keep a clear and valid blockchain, but I am having a hard time trying to wrap my head around fake transactions.

Let me explain. As I understand it :

Nodes in the network produce transactions.
They are repeated all across the network
At the same time, some nodes try to mine a block.
When someone resolves the hash, they can create their block.
The block is accepted by everybody on the network as they can immediately check Proof of Work (via the hash + the data)

Ok so this basically means that everybody follows the consensus (otherwise, everything said by anybody else would be garbage to a Node, and the other way round : we would have an isolated node). But how do they know that the transactions themselves written in the new block are correct ?

For instance, let A and B be two accounts. What prevents a node from randomly saying "B gave n bitcoins to A", and that information being completely false ? B would obviously benefit from doing that.

Maybe I don't understand how consensus is enforced in nodes themselves as well... is everybody running the same "program" ? Is it something in the protocol itself ? Does the consensus "know" when a transaction cannot be made for some reason ?

Thanks for your help


texts:
I've been using 2-of-2 on bitpay for some years, but relying on just one wallet, which can have its source code backdoored with malware, is very dangerous.
I've been researching about multisignature over different wallets, which makes it harder for these things to occur.
Electrum works with lots of other wallets but it's very user unfriendly. The only other one I know is BlueWallet, but its package.json dependencis worry me a lot: https://github.com/BlueWallet/BlueWallet/blob/master/package.json#L67
What would be a good solution for multisignature over 2 different wallets?


texts: How to complete install of bitcoin-0.17.1 on linux (fedora 29)

texts: So I downloaded and unzipped bitcoin core. I now have bitcoin-0.17.1 sitting in my home directory . What next? How do I install and run this? (Obviously I am a newb, help much appreciated.)


texts: most profitable scrypt mining machine per dollar with unlimited budget and free power?

texts:
I know The 7950 is the most efficient in (MH/s)/$/watt... but I have contractual access to unlimited free power. I'm already using the power anyway so the marginal cost of the power is actually zero. Is there a machine I could build and turn a profit with at this point? Litecoin is not the most profitable Scrypt coin to mine now, so don't assume I'm mining Litecoin.
The asics coming out "soon" might be a concern, if they actually even come out soon, but its my understanding that they are good for being low wattage, whereas the hash/dollar is similar to GPUs still.
Assuming I could be confident that a Scrypt asic manufacturer is trustworthy enough to buy from, I wouldn't be opposed to doing that, but thats really a pretty big gamble, unlike ordering a bunch of parts from amazon/newegg on cyber monday.
Also I'll be able to resell GPUs, so even if this becomes non-viable after 6 months or so, I'll be able to recover a decent chunk of my investment.
I say "unlimited budget" meaning I can fully saturate a motherboard with GPUs or purchase an asic without an issue, whatever the most efficient is.


texts:
Just a basic/general question, recently when I send bitcoin using blockchain.com's wallet I noticed within my transaction logs Received BTC to: BTC Trading Wallet. From: BTC Wallet directly after Sent BTC To: ....... I'm just wondering why this is occurring and what exactly is BTC Trading Wallet and why my funds are being sent to BTC Trading Wallet?
It almost appears as a duplicate transaction but to my " own address "?


texts:
I want to first create a transaction with 0 fee (tx1).

Next, I am going to use an output of tx1 as an input in another transaction with the necessary fees.

The issue is now that tx1 gets rejected by full nodes. Why can't I broadcast a 0 fee transaction?


texts:
ERROR: ConnectBlock() : coinbase pays too much (actual=20000000 vs limit=20000000)

I got this error at my debug.log

anyone know how to fix this issue? I am coding a new coin, changing its rewards, which parametter I need change to increase the limit.

on the line:

 if (vtx[0].GetValueOut() > GetBlockValue(pindex->nHeight, nFees, pindex->nBits))
        return state.DoS(100, error("ConnectBlock() : coinbase pays too much (actual=%"PRI64d" vs limit=%"PRI64d")", vtx[0].GetV$

I changed my nsubsidy for the code

int getrandint(int min, int max)
{
    int num;
    num=rand();
    num=num%(max-min+1)+min;
    return num;
}

int64 static GetBlockValue(int nHeight, int64 nFees, unsigned int nBits)
{
    if (nHeight == 0)
    {
        return nGenesisBlockRewardCoin;
    }

   unsigned int i, iMax, iMin;

   iMin = 1;
   iMax = 50;

if(nHeight<500)
{
iMax = 3;
}
if(nHeight > 8000)
{
iMax = 30;
}
if(nHeight > 20000)
{
iMax = 20;
}
if(nHeight > 100000)
{
iMax = 10;
}

  i = getrandint(iMin, iMax);
    int64 nSubsidy = nBlockRewardStartCoin * i ;

    // Subsidy is cut in half every 60480 blocks (21 days)
    //nSubsidy >>= (nHeight / 60480);

    // Minimum subsidy
    if (nSubsidy < nBlockRewardMinimumCoin)
    {
        nSubsidy = nBlockRewardMinimumCoin;
    }

    return nSubsidy + nFees;

}

The code originally was

int64 static GetBlockValue(int nHeight, int64 nFees, unsigned int nBits)
{
    if (nHeight == 0)
    {
        return nGenesisBlockRewardCoin;
    }

    int64 nSubsidy = nBlockRewardStartCoin;

    // Subsidy is cut in half every 60480 blocks (21 days)
    nSubsidy >>= (nHeight / 60480);

    // Minimum subsidy
    if (nSubsidy < nBlockRewardMinimumCoin)
    {
        nSubsidy = nBlockRewardMinimumCoin;
    }

    return nSubsidy + nFees;
}

Because of what I change, my code give the error coinbase pays too much

root@eatSushi1:~/dogequark/src$ ./dogequarkd
dogequark server starting
root@eatSushi1:~/dogequark/src$ terminate called after throwing an instance of 'std::runtime_error'
  what():  CreateNewBlock() : ConnectBlock failed

I also got this error when I run the coind at another server after cloning through github.


texts: bitcoin-cli get all tx hashes for watch-only address

texts:
does bitcoin-cli have any functionality to get all tx hashes for a given address (ie the txs that either send or receive funds from the given address). listtransactions sounds like it should do what i want, but when i run it like so then i get no results:
# pick a random address to watch from blockchain.info:
$ addr=1GkktBuJ6Pr51WEJe5ZzyNvMYaMDFjwyDk
# create a watch-only account for this address, with the account name
# being the address itself, for convenience:
$ time bitcoin-cli importaddress $addr "$addr" true
real    41m59.505s
user    0m0.004s
sys 0m0.004s
$ bitcoin-cli listtransactions "$addr" 100 0 true
[
]
$ bitcoin-cli getinfo
{
    "version" : 100200,
    "protocolversion" : 70002,
    "walletversion" : 60000,
    "balance" : 0.00000000,
    "blocks" : 384809,
    "timeoffset" : 0,
    "connections" : 8,
    "proxy" : "",
    "difficulty" : 65848255179.70261383,
    "testnet" : false,
    "keypoololdest" : 1381701523,
    "keypoolsize" : 101,
    "paytxfee" : 0.00000000,
    "relayfee" : 0.00001000,
    "errors" : ""
}

as you can see, it takes 42 minutes to scan the blockchain for this watch-only address, so its not something i want to do often. and its only producing an empty list, whereas blockchain.info shows there are 6 transactions.
why is this not working? is this not the intended functionality of bitcoin-cli listtransactions?
update
listtransactions is supposed to display transactions from watch-only addresses:
$ bitcoin-cli help listtransactions
listtransactions ( "account" count from includeWatchonly)

Returns up to 'count' most recent transactions skipping the first 'from' transactions for account 'account'.

Arguments:
1. "account"    (string, optional) The account name. If not included, it will list all transactions for all accounts.
                                     If "" is set, it will list transactions for the default account.
2. count          (numeric, optional, default=10) The number of transactions to return
3. from           (numeric, optional, default=0) The number of transactions to skip
4. includeWatchonly (bool, optional, default=false) Include transactions to watchonly addresses (see 'importaddress')
...
...
...


texts: Someone made a small, apparently fraudulent, transaction to my public address. What is the purpose behind it?

texts:
I have a small e-commerce site and someone made three cryptocurrency purchases just seemingly to know my public addresses as she never paid the cost of goods. The three addresses she viewed are public derived from the master public key so there shouldn't be any security problems there afaik.

She seemingly wanted to know my BTC, ETH and LTC addresses but only made a small transaction of $1.89 in BTC. I got 0.2¢ and other address got the rest. Here's the blockchain transaction data.

By the multiple transactions from this address and others related to it, it looks like if someone is trying to move a large quantity of BTC through multiple addresses to make it difficult to track. But why using public addresses from e-commerce sites like mine? Shouldn't be the same creating multiple new addresses? Maybe you can extract more meaning from this transaction and the intention behind it.

For additional info, the IP from where she made the purchases at my site is 68.65.122.134


texts: Electrum error "server did not answer" when trying to send?

texts: I am now getting this error.  Several sites discuss it, but they are all fairly old.  I have restarted electrum, and restarted the computer.  Selecting a different server either doesn't help, or it stops being connected.  Have tried to upgrade, but get an error that apparently is a legit bug.


texts: Do Bitcoin futures contracts affect Bitcoin price?

texts: Since Bitcoin futures are cash settled, no Bitcoin are actually exchanged at the time of the expiration of the contract.  Can one assume that since no Bitcoin are exchanged, then Bitcoin supply and demand would not be directly affected and therefore the Bitcoin price would not be affected? If not, then how do futures contracts affect the price?


texts: MultiBit sends BTC to different adress then I wanted

texts:
Bug report
  Operating System: Windows 7
  MultiBit Version: 0.5.15
  Steps to replicate the problem: send BTC to specific adress
Hello I have a problem with sending BTC, what happened to me was, that when I sent BTC to my btc-e account (I used the adress they gave me for deposits), I checked everything (the amount of BTC I wanted to send and the adress) and I hit send. Problem was, that it never arrived on the adress I wanted it to and I never got my account funded. I started dealing with btc-e support, but it had not gotten me anywhere so far. But while taking screenshots as proofs I came across my transaction history.

As you can see I only used this wallet to fund my btc-e account so I sent BTC to only one adress, which is always the same (1cU8kgoVBGMxafj9ynwYjNJJH3L3PsSw7) but in those two other transactions its sent to "1cU8kgoVBGMxafj9ynwYjNJJH3L3PsSw7" (146rSpmvzyvZ4BYWCCt9fnMRLfL527CKcW) and I dont really know what that means. Except for that this adress (1cU8kgoVBGMxafj9ynwYjNJJH3L3PsSw7) never got the BTC i sent, I looked into my btc-e history and I realized that I never even got the first transaction which had this("1cU8kgoVBGMxafj9ynwYjNJJH3L3PsSw7" (146rSpmvzyvZ4BYWCCt9fnMRLfL527CKcW)) as sent to. How can I get my BTC back? I didnt do any mistake and I dont know how is this possible.
With regards Poloch


texts: can I download the litecoin blockchain from the webbrowser?

texts:
even with 13 active connections, the blockchain seems to be downloading at an unreasonably slow rate. considering the large amount of traffic, the sooner the sync the better as it's possible that it will grow by a lot while I'm still downloading.
my provider seems to slow the internet whenever something peer-to-peer is happening(certain video games,etc) so the fact that it's such a large file downloaded over P2P is also a  concern.

I want to be able to simply store coins I get today and in the future, not look at all the non-existent past ones. while multibit does this for bitcoin, I can't find a similar app for Litecoins.


texts: If I backup my wallet.dat once, am I forever safe?

texts:
I have a dogecoin (though should be similar to bitcoin/altcoins) wallet and I encrypted and backed up my wallet.dat file to a few different places (different cloud providers).

Now, assuming I never create a completely new wallet, do I ever need to update the wallet.dat file that I have backed up?


texts: Why is this transaction unconfirmed after a few hours?

texts:
https://blockstream.info/tx/8ede5096427abea7d7829aba85f491bb93d42aa4f9aa9dbd25f6862958c3609c
It says
ETA
in 4 blocks (13.24 vMB from tip)
Why is ETA in 4 blocks? What does it mean by 13.24 vMB from tip? What is the tip?
0.0000616 BTC (27.6 sat/vB)
My transaction fee is 27.6 sat/vB which seems to be high enough.


texts:
I am trying to fully understand the block chain algorithm and in particular, the consensus.

My understanding is each miner has a pool of pending events -- events that have not yet been included in a block --.

What I can't get my head around is if I'm busy mining events A, B & C into a block. Then in the mean time, a new block arrives that already includes event A, and its chain represent the "most work chain". I should abandon my effort to mine and start mining again after this new block.

If that's the case, then when I restart mining, my pending events should only have B and C. That I understand.

But if the new block that now becomes the head of the block chain was not parented by my current main block, that means that I could duplicate event B & C (if the parent of the new block contained them).

So how do I need to manage pending events? Do I need to go back the new chain to make sure I don't make duplicates?


texts: How is it possible that webservers with deterministic wallets can produce public keys without knowing the underlying private key?

texts:
I came across this quote on bitcoin.it: BIP_0032

  elliptic curve mathematics permit schemes where one can calculate the
  public keys without revealing the private keys. This permits for
  example a webshop business to let its webserver generate fresh
  addresses (public key hashes) for each order or for each customer,
  without giving the webserver access to the corresponding private keys
  (which are required for spending the received funds).

This lead me to read more about some custom wallet implementations, namely pycoin. After looking through the code, I still can't understand how it is possible to generate public keys without giving the server access to the private key.


texts:
I have been reading the SHA256 hash creation with a random nonce. So, my understanding is every miner would pull uncommited transactions and would try to create a Hash of the transactions with a random nonce starting with 0 and increment from there on. So, if every node/miner is performing the same hash with the nonce sequence starting from 0, it would always be the miner with the maximum computing power always outrun the smaller ones. How would a miner with lesser computing power ever be able to create a hash quicker than the largest one?

My second question is every time a block is added to the chain, would every miner stop their current process and restart all over again since the next block would depend on the hash of the currently added block?


texts: How do I get hash to verify transaction?

texts:
If I have the public key and signature for a transaction how do I get the hash value that is used in verify(hash, sig, pubkey). I want to know how to work backwards from a raw transaction to get it,  not how to build it.

My question is basically this one

How to verify the signature of a raw transaction

But the answer given I think is for getting the Transaction ID hash which I have tried and it doesn't work.


texts: I have a Gridseed 5-chip ASIC miner and am running 2 amps into it. Will this impact how it works and if it works at all if I use 2 amps instead of 5?


texts: what is the different between bitcoin network and the bitcoin protocol

texts: protocol and network seem like two separate things. When peeps refer to bitcoin then it could mean protocol, software (what do they mean by that) or the network (what exactly do they mean by that ?) or currency ?


texts:
I am working on a blockchain parser. I first parse the header index to know where the data is located in the .blk files. And then I parse the blk files in the right order. (I use the data from my full node)

However I noticed that I am including an extinct block (see Single tx included in two different blocks) while parsing (and blockchain.info seems to do the same).

How is that possible? How to get the actual block?

While parsing the index I check the condition NStatus&(blockHaveData|blockHaveUndo) != 0 before including the block, is that enough?

A validated block has NStatus = 0x9d whereas the extinct block has NStatus = 0x8b.

There does not seem to be another valid version of the extinct block in my index (height 525890)

Edit: The error comes from my validation condition NStatus&(blockHaveData|blockHaveUndo) != 0. As a temporary fix when a given height is referenced twice in the index I keep the on with the largest NStatus.


texts: How do I move wallet.dat file to a different location?

texts: I want to move (not backup, move) the file to a different location. That way bitcoin wallet software open that file up.


texts:
i have a confuse about the "getrawtransaction" RPC function,it returns a json object, which contains the addresses list in the "vout" object,like below.It took me some time to understand when the multiple addresses will contains many items,as i see, it always only one item, After reading the source code, I also found that even for multi signature transactions, there will not be multiple addresses. I need somebody help！please！

 {
      "value": 1000000,
      "script": "a914d550ecfc60d9f976de1f2a43bdf4e491b684cd6887",
      "spent_by": "cd2494071876f91e1f9505f5c5421088c7df2e6f939c17f742d3638bc7df789a",
      "addresses": [
        "3M8voDot82tBrQE7QWGy9WUWxp7gDU7owx"
      ],
      "script_type": "pay-to-script-hash"
 }

full url is: https://api.blockcypher.com/v1/btc/main/txs/46001fade64b8fa23815066ec62cc4a91ee0c8f4a4fad26e428bc4c0a2146290

I tried to send a multi sign transaction to the test network, and then looked at the data, and found that there was only one address.


texts: How much internet traffic and bandwidth does mining with a pool need?

texts:
As you know the new Antminer S9 is available and its hash rate per second is 14TH.
Now, my question is if I buy one of these, how much internet traffic and bandwidth do I need for mining by pool and how much for solo mining (and is it different for two machines or so).


texts: What is the precise nonce finding protocol?

texts:
There are many descriptions of what mining is, but none of them describe it exactly. From what I gather:

  Mining means finding a nonce c such that for some information s the hash value h(s||c) begins with a certain number of zeros (h is sha-256, || concatenation).

The "information" is given here. The nonce is an integer that is incremented in the mining process. But it seems that it's not s||c that is hashed, but rather there is some double hashing going on, but of what, h(s)||c, h(s||c), h(s)||h(c)? I can't deduce it from the Python code in the previous link (NB: I'm code illiterate).

Also the nonce isn't just initialized at zero and then incremented until there's success:

  To avoid risking wasting work in this way, there needs to be a random starting point, and so the work becomes to find H(s,x,c)/2^(n-k) = 0 where x is random (eg 128-bits to make it statistically infeasible for two users to maliciously or accidentally start at the same point), and c is the counter being varied, and s is the service string. (source)

But that's the article describing hashcash, and who knows bitcoin might not have implemented the hashcash protocol as it was proposed.

So my question is, what is the exact protocol? I'd go and read the source code if I could but like I said I'm not code literate. Surely the answer must be possible to formulate concisely, something like:

  Compute h(s||c) where c runs over 0,1,... until value begins with 15 zeros.

or

  Hash s and obtain x in manner X, then compute h(h(s)||c) where c runs over x,x+1,..., until value begins with 17 zeros.

Sorry if this has been asked before, if so clearly I'm googling the wrong words, thanks.


texts: How to differentiate between sending and receiving address in blockcypher api result?

texts:
I am using BlockCypher's API to get a list of transactions for a bitcoin address. I need to maintain a record of IN and OUT transactions from this address with time and transaction hash. However, I am not able to differentiate between the receiving and sending address. It is so much clear with Etherscan.

API Endpoint :

https://api.blockcypher.com/v1/btc/main/addrs/1rundZJCMJhUiWQNFS5uT3BvisBuLxkAp/full?confirmations=3&limit=2000

Can someone please help me differentiate it?


texts: What should you set as rpcpassword and rpcusername in BitCoin?

texts:
Every example/tutorial looks the same:

rpcpassword=<somehashofsomesort> and rpcusername=rpcuser

They always use something like rpcuser, and some hash for the password. Why is it like this? Does it offer any advantage to break out of the shell and have your username and password be something you like?

In another place I found this:

#rpcuser=alice
#rpcpassword=DONT_USE_THIS_YOU_WILL_GET_ROBBED_8ak1gI25KFTvjovL3gAM967mies3E=

Does setting your username to alice cause you to no longer be anonymous, and that's why everyone has the same username?

Do I even need a username and password?


texts: What actions trigger the need to obtain a new backup with Blockchain.info/wallet?

texts:
Other clients, including Bitcoin-Qt, use a key pool so that a backup is still valid for a while.

Blockchain.info/wallet doesn't use a key pool.

After a backup of the wallet is obtained and archived, when would a new backup be needed?

[Specifically, does Quick Send send change to only existing addresses?]


texts: How to generate a new receive address for each transaction on the Nano Ledger S?

texts:
I am wondering if it is possible it have a new receive address each time I receive a crypto. Some exchanges do this for you automatically, but I noticed each time I hit 'display' it was the same address.

Is there a way to have a new receive address for each transactions?


texts:
I'm new in the Bitcoin World. Today I did my second transaction for just 0.005 BTC but 2 hours after, it's unconfirmed yet. The transaction is in the block 320385 and it is orphaned. I saw the statistics for orphaned block in blockchain.info and today are 10 orphaned blocks and this is a high value according the graphic.

My cuestion is:

1.- How much time will my transaction to be included in other block?.

2.- What happened on september 13, 2014?, Why are there 10 orphaned blocks?

Thanks


texts:
I've been trading BTC in the UK via bank transfer for a while now and may begin doing cash purchases soon. I've realised that it is critical I document the cash withdrawal as an expense so that I get taxed only on the profit and not the entire turnover of the bitcoin sale. Usually this is done via the means of keeping receipts - so I guess I could have some sort of receipt that documents the exchange but I'm not sure where to begin.

What kind of information do I put on it?
What is the bare minimum information I need on the seller?
Considering it is me issuing this document it's not exactly an invoice or a receipt, is there a word for it?


texts: I read about the fact that segwit2x will split the BTC in BTC 2X. What will happen to BitCoin Cash BCH.


texts:
I am learning and trying to implement my own cryptocurrency and I am thinking about how could I achieve the peer to peer connections.

I read that bitcoin is using DNS seeds for discovering users.
In such case when running full node at home, one must configure his router to forward the port, firewall, etc..

What do you think about webRTC technology? Do you think this could be good way of solving p2p network? In this case, no router configuration is needed and firewall is ok.

Do you see some pros/cons of these aproaches?


texts: How many coins are active in Bcash chain

texts:
How many coins have moved in Bcash chain since the fork?
Does any web publish a graph tracking this value?

It would be interesting to see how does it compare with an updated version of the chart below (source) to check how many old coins were moved to claim BCH apart from the ones split by the exchanges.


texts: I purchased 250$ worth of bitcoin back in 2012 on coinRnr and made two transfers with coinRnr with what I bought from them too two different addresses. I was quite messed up at the time since I spent most of that money on Silkroad but do know that I had 106$ of bitcoin left that I bought and I am hoping it is still out there. I have the emails from coinRnr and Blockchain wallet that's empty and bitstamp which I can't remember my password. With the email from coinRnr that had the address they sent the bitcoin to can I find out what wallet it went to or is that not possible ?


texts: Good resource for understanding the peer to peer protocol sequence

texts:
I'm looking for a good  explanation or reference on the peer to peer aspects of the two main bitcoin actors- the clients(wallets) and miners.

Satoshi's white paper, in section 5. Network, gives a very high level overview of the steps to run on the network, yet what I'm looking for is a description of the handshake sequences, how the peers broadcast, collects new transactions, and how they request missed blocks.

I've read and somewhat understand the protocol at https://en.bitcoin.it/wiki/Protocol_specification
I also have a solid understanding of the crypto, ECDSA, SHA-256,  RIPEMD-160, Merkle trees, and Hashcash (and a bit of RPOW) so no need to cover that in particular.

What would be really helpful is a sequence diagram, if anyone knows of one, and a paper or article that goes into more detail than the whitepaper.

Any help, beyond "read the **'ing source code' would be great ;-)


texts: How to sign a transaction with multiple inputs?

texts:
I have been able to program an application in python that sends valid transactions that spend 1 input, but I really can't get it to work with 2 or more inputs.

So my question is, how exactly is the hash that has to be signed for each input calculated?

What I have been doing so far, is, for example, if we have 2 inputs, we generate a transaction that spends only that first input, and thats the hash that has to be signed for the first input. And the same with the second input, we generate a transaction that only spends that second input. Both transactions need to have the same outputs.

Is that correct? For example, we want to spend input aaaa:0 and input bbbb:1 and we want to send them to some address:

To calculate the hash that the first input has to sign, we need to generate this transaction:

'version': 1,
'inputs': (1)
    'output_tx_hash': 'aaaa',
    'output_position': 0,
    'script': the original script, like: '76a914' + hash + '88ac',
    'sequence': ffffffff,
'outputs': (1)
    'value' : 100000
    'script' : '76a914' + hash of btc pub key + '88ac'
'locktime': 0

And to calculate the hash that the second input has to sign:

'version': 1,
'inputs': (1)
    'output_tx_hash': 'bbbb', # this changes
    'output_position': 1,     # this changes
    'script': the original script, like: '76a914' + hash + '88ac',
    'sequence': ffffffff,
'outputs': (1)
    'value' : 100000
    'script' : '76a914' + hash of btc pub key + '88ac'
'locktime': 0

We serialize them, add them 01000000 (SIGHASH_ALL), double sha256 that, sign it, and add 01. That way we get the two signatures that we will use on each input respectively. My application does exactly that and doesn't work. What am I missing?


texts:
I used bitcoinj library for wallet and it generates 12 word mnemonic seed.

But I made changes in it and created 24 word mnemonic seed.

But I need to convert old 12 word mnemonic seed into new 24 word mnemonic seed.

Please help me with this.


texts: How can I pass Multiple addresses in Move command

texts: I have to pass multiple addresses in move command but I am not able to pass as it is not accepting more than one wallet address Is there is any another way to move the balance to multiple addresses.


texts: I am a complete newbie. I transferred money to my coin base paper wallet before printing my private key. Now, I see my btc in wallet but could not retrieve my key by going back on my browser...Are they gone?


texts: How many confirmations in litecoin block explorer

texts:
When I call url http://block-explorer.com/address/[my address]
to see how many litecoin Received by that address, How do I know how many confirmations it has ?


texts:
What wallets currently support RBF?
Is there some workaround if they don't?


texts: What is Delegated Proof of Stake (DPoS)?

texts: I know that it is a consensus algorithm that is different from Proof of Work (PoW) and Proof of Stake (PoS) which is used in a few blockchains including but not limited to STEEM, BitShares and ARK, but how does DPoS work?


texts: Is there a rippled Windows binary available for download?

texts: Is there a compiled Windows binary for the Ripple deamon rippled available for download? I only found its source code...


texts: How can I successfully exchange my Indian or Digital Rupee Currency into my BTC wallet?

texts: I need information how to transfer from my Rupee eWallet and set amount of earned Currency, then send it to my Bitcoin Wallet. Any advice would be appreciated.


texts: What's the most popular Namecoin exchange?

texts: There are several Namecoin exchanges listed at official wiki and Bitparking seems to be the oldest, but which one is the most used?


texts: what is exact meaning of some field of response of `getBlock` rpc api

texts:
I refer to this document for using getBlock rpc api.

https://bitcoin.org/en/developer-reference#getblock

{
  "hash" : "hash",     (string) the block hash (same as provided)
  "confirmations" : n,   (numeric) The number of confirmations, or -1 if the block is not on the main chain
  "size" : n,            (numeric) The block size
  "strippedsize" : n,    (numeric) The block size excluding witness data
  "weight" : n           (numeric) The block weight as defined in BIP 141
  "height" : n,          (numeric) The block height or index
  "version" : n,         (numeric) The block version
  "versionHex" : "00000000", (string) The block version formatted in hexadecimal
  "merkleroot" : "xxxx", (string) The merkle root
  "tx" : [               (array of string) The transaction ids
     "transactionid"     (string) The transaction id
     ,...
  ],
  "time" : ttt,          (numeric) The block time in seconds since epoch (Jan 1 1970 GMT)
  "mediantime" : ttt,    (numeric) The median block time in seconds since epoch (Jan 1 1970 GMT)
  "nonce" : n,           (numeric) The nonce
  "bits" : "1d00ffff", (string) The bits
  "difficulty" : x.xxx,  (numeric) The difficulty
  "chainwork" : "xxxx",  (string) Expected number of hashes required to produce the chain up to this block (in hex)
  "nTx" : n,             (numeric) The number of transactions in the block.
  "previousblockhash" : "hash",  (string) The hash of the previous block
  "nextblockhash" : "hash"       (string) The hash of the next block
}

I want to know meaning size and bits

What is size field mean?? block size as byte??
What is bits field mean?? block size as bits??

May I use chainwork diff for calculating hash power for each block?

According to this doc, https://bitcoin.org/en/developer-reference#getblock, chainwork means

 "chainwork": "xxxx"           (string) total amount of work in active chain, in hexadecimal

For example, let's assume that chainwork of block 12345 is 1111 and that of block 12344 is 1100.

Then may I consider that hash power for block 12345 is 11 since 1111 - 1100 is 11?


texts: How does the structure of a segwit block differ from a non-segwit block?

texts: Is there any difference in the structure of a segwit block in comparison to a traditional non-segwit block? A diagram would be helpful if possible.


texts:
I am trying to write a bot to use it on Bittrex with nodeJs, but the documentation is very poor. My problem is that I would like to be able to buy the last ask, like when in the web you click in bid the option ask, this way the buy is instant.
For developing the bot I am using:
 https://github.com/n0mad01/node.bittrex.api
I have tried:

 bittrex.buyLimit({ market: 'BTC-ETH', quantity: 0.001, rate: "ask"}, function (data) {
    console.log("Response: " +data);
})

but it does not accept the rate "ask", is there any way this can be done?


texts:
There are some services to get the list of current known peers,
like those offered by 21.co or Blockchain.info
but I can't find anything similar for the Testnet network.

Does anybody know a Testnet peer list?

Actually, it is also very hard to find any IP testnet address.
Is there a reason for that?


texts:
3 years ago i bought a little bit of Bitcoin. Today i found the private key of my wallet. But I cant access it, I need these 12 words (backup) I dont have.
Why cant I access my Bitcoin Wallet with Private Key? (Like Myetherwallet, here you can access wallet with private key)


texts: In DASH, why is in the coinbase transaction sometimes the first output the masternode reward, and other times the second?

texts:
Example of the first output being a masternode reward
Example of the first output being a proof-of-work reward

What determines the order of the outputs in the generation transaction?

As far as I understand it:

In src/miner.cpp in the CreateNewBlock function it is determined that the vout index for proof-of-work is 0. Line 86-90:

CMutableTransaction txNew;
txNew.vin.resize(1);
txNew.vin[0].prevout.SetNull();
txNew.vout.resize(1);
txNew.vout[0].scriptPubKey = scriptPubKeyIn;

Later on in the function it calls the FillBlockPayments function In src/masternode-payments.cpp Line 294:

FillBlockPayments(txNew, nHeight, blockReward, pblock->txoutMasternode, pblock->voutSuperblock);

which calls the FillBlockPayee function. Line 222:

mnpayments.FillBlockPayee(txNew, nBlockHeight, blockReward, txoutMasternodeRet);

There the masternode reward is appended as an additional vout to the transaction txNew. Line 287-291:

// split reward between miner ...
txNew.vout[0].nValue -= masternodePayment;
// ... and masternode
txoutMasternodeRet = CTxOut(masternodePayment, payee);
txNew.vout.push_back(txoutMasternodeRet);

Why then, in the generation transaction, is the first output not always the proof-of-work reward?


texts: How can I see a non-wallet transaction in Bitcoin core

texts:
If I run the command gettransaction "txid" in Bitcoin core with a transaction id that doesn't belong to my wallet, I get "Invalid or non-wallet transaction id (code -5)".
I can see the details of the transaction in any block explorer, but I would like to see in my Bitcoin core the same information that is shown in those block explorer.


texts:
I couldn't understand if this tendermint protocol is proof-of-stake or something like proof-of-lock?

https://tendermint.com/static/docs/tendermint.pdf


texts:
I tried to put bitcoins into an p2p exchange with bitcoin-qt. I added a to small transaction fee, so the coins are now stuck as "Unconfirmed". The offer from the exchange is overdue, so all that will happen if the transaction gets confirmed is that I get them back with an administrative fee.

I would like my coins right now and avoid paying the fee. I've read that you can double spend the coins back to yourself and if I add a higher payment fee than the first time this would probably override the original payment. How can I practically do this? I'm not a hardcore developer but feel comfortable using commandlines and know my way around computers.


texts: I'm trying to hash transactions together to find the Merkle Root!

texts:
Transaction #59500 has 045c670f1c02c919  as its coinbase. Transaction 1 is 6653ad77d695752cff9fe63bbb5702a53807be534c537251d53de06aac5ca093. Transaction 2 is 72e8781092c01e9eb1c21ba33d52ad6abc42f3807601bcd8b8074d583446346e.

Double SHA256 of Coinbase

import hashlib
header_hex = ("045c670f1c02c919")
header_bin = header_hex.decode('hex')
hash = hashlib.sha256(hashlib.sha256(header_bin).digest()).digest()
hash.encode('hex_codec')
'6eafdb5c504ed7e70536d70c666503f4435205f367f21d2960ff2262ca2acf0b'
hash[::-1].encode('hex_codec')
'0bcf2aca6222ff60291df267f3055243f40365660cd73605e7d74e505cdbaf6e'

Double SHA256 of Transaction 1

header_hex = ("6653ad77d695752cff9fe63bbb5702a53807be534c537251d53de06aac5ca093")
header_bin = header_hex.decode('hex')
hash = hashlib.sha256(hashlib.sha256(header_bin).digest()).digest()
hash.encode('hex_codec')
'b2e28ac8528477c0c3c7978ee29479ae9ca1aed9cb2e58e6b910f17142f6c53d'
hash[::-1].encode('hex_codec')
'3dc5f64271f110b9e6582ecbd9aea19cae7994e28e97c7c3c0778452c88ae2b2'

Would I then combine the double hash of the coinbase with the double hash of transaction 1? Like so:
("0bcf2aca6222ff60291df267f3055243f40365660cd73605e7d74e505cdbaf6e" + "3dc5f64271f110b9e6582ecbd9aea19cae7994e28e97c7c3c0778452c88ae2b2) and then double hash that?

The double hash of the coinbase and transaction 1 is d77fefa4fd82afdf1780f84dae5dc30be2f3b53bc8db2c40db6d17687324dc48

Double SHA256 of Transaction 2

header_hex = ("72e8781092c01e9eb1c21ba33d52ad6abc42f3807601bcd8b8074d583446346e")
header_bin = header_hex.decode('hex')
hash = hashlib.sha256(hashlib.sha256(header_bin).digest()).digest()
hash.encode('hex_codec')
'c9f7032f5df64761e74ad4bc7cb653db8c78aed331926382ca37ec3b8d8625a9'
hash[::-1].encode('hex_codec')
'a925868d3bec37ca82639231d3ae788cdb53b67cbcd44ae76147f65d2f03f7c9'

Would I then hash a925868d3bec37ca82639231d3ae788cdb53b67cbcd44ae76147f65d2f03f7c9 with itself?

header_hex = ("a925868d3bec37ca82639231d3ae788cdb53b67cbcd44ae76147f65d2f03f7c9" + "a925868d3bec37ca82639231d3ae788cdb53b67cbcd44ae76147f65d2f03f7c9")
header_bin = header_hex.decode('hex')
hash = hashlib.sha256(hashlib.sha256(header_bin).digest()).digest()
hash.encode('hex_codec')
'4075e4ac60dd8a52ed3eb69520ad71d660c8c2bcbf4073c87fd633a276cb2921'
hash[::-1].encode('hex_codec')
'2129cb76a233d67fc87340bfbcc2c860d671ad2095b63eed528add60ace47540'

Lastly when I try to combine that hash of the coinbase and transaction 1 with the hash of transaction 2 with itself...
''d77fefa4fd82afdf1780f84dae5dc30be2f3b53bc8db2c40db6d17687324dc48' + ''2129cb76a233d67fc87340bfbcc2c860d671ad2095b63eed528add60ace47540"

I got this 012853eb35789c270fc72dc11b4b9e24710f6f02793344860bdcad7f25e771e1 when the merkle root is :

ff682ef66cd1b56213fd4db9462fb138f6d8c16d706d41969a7eacc819528038

What did I do wrong?


texts:
I tried to to host bitcoin core json-rpc to listen other than localhost but it would not work even i set it to listen to ip 0.0.0.0

My config (for bitcoin.conf)

testnet=1
server=1
daemon=1
listen=1
rpcuser=something
rpcpassword=secret
rpcport=8332
rpcconnect=0.0.0.0

So how do i make it so that it will listen to ip other than localhost or 127.0.0.1?

VPS informations:

Ubuntu 16.04

Latest Core (just installed it today)

client is remote


texts:
Through dogecoin-cli, I sent half the dogecoins I own to an external address. Now, when I call the listaccounts function, I get this:

[root@web ~]# ./dogecoin-cli listaccounts
{
    "" : -25001.00000000,
    "doge" : 48136.85072100
}

Notice how the "" has -25001.00000000. I am using a query from php to get the balance of "doge" and display it to users. That returns 48136.85072100, which is a problem, because I only have 23135.85072100 doge. How can I fix this problem? Thanks!


texts: Why does transaction activity show on the blockchain for my Bitcoin address at my hosted (shared) E-Wallet service?

texts:
I have an online wallet at localbitcoins.com (address 12pHFR5yv2KGqck5N8teb5MgoRtzAgLRn2).

I made three transfers to it, for a total of 0.5 BTC + 0.5 BTC + 0.3031 BTC = 1.3031 BTC.

Blockchain.info did show my address receiving coins. However, it is showing my address sending coins to several addresses after receiving them https://blockchain.info/address/12pHFR5yv2KGqck5N8teb5MgoRtzAgLRn2:

Is someone using my online wallet at localbitcoins.com to withdraw money?


texts:
Let's say UserA uses electrum, connected to ServerB, and hits the "Send" button to do a transaction.

What happens?

The transaction is sent to ServerB only

or

The transaction is sent from UserA to ServerB but also to 2 (or 10 or 100?) other servers (UserA's electrum has a list of 100 servers to connect, one after another, when he does a transaction)

or

The transaction is sent from UserA to ServerB only, but ServerB broadcasts it immediately to 2 (or 10 or 100?) other servers

Especially if ServerB is late of 1 or 2 blocks from the rest of the network, what happens? Is the transaction lost? Broadcasted anyway?

Where are these rules specified in the official implementation?


texts: How do I restore my Multibit wallet without seed words?

texts:
So I created my BTC wallet back in 2013 and had always kept a backup of the files handy. The computer I used has since died and now that I've installed the latest version of Multibit on my new computer, I can't figure out how to restore my wallet. It asks me for seed words, but I do not recall ever having seed words when the wallet was created.

I have the files multibit.info, multibit.wallet, and wallet.aes.json among other backups (along with my password). How do I get to a point where I can get my wallet up and running again?


texts: What can I do if someone obtained control of my blockchain wallet?

texts:
I fell for a bitcoin scam and I would like to undestand what are the risk associated to it.
i established contact with scammer on instgram he convinced me to join the mining pool i had to create a new blockchain wallet and deposit founds and send them to one of the addresses he gave me.
I still have access to that wallet but I dont use it anymore for my transactions.
after that intese experience I decided to research the crypto space more deeply and do it by myself instead of relying and giving trust to random people that promise gains.
That was a huge mistake, I am ashamed of what I did and this is my intent undestand more,and don't forget that mistake.
I lost my money but i also lost the keys of my blockchain wallet.
what should i do ?

I did the account as they asked and money where in the account, but I couldn't access them. after i realized that they sent me this :Hello Sir,
We noticed that you want to make withdrawal in your account. Due to the irregularities encountered from your wallet ,there has been a glitch in the withdrawals process, you will need to pay for tax of %10 percent of your money in your account now to be able to with your money fully. Thank you.
after that which i didn't do
i realized that the website they linked me, and asked me to create a profile, in order to complete the withdrawal was asking to  put my bank details to complete the deposit.
At that point, I stopped and I never shared any of my bank details.
we kept talking he tried to get more money from me and i tried to get my money back, now he is gone blocked me on whatsup.
Was this website a strategy to get my bank account?Can be a way to create a backdoor access?
My biggest fear is that I don't understand if there is a larger scam happening or their only goal was to get my money? if so why did they needed my blockchain account?


texts: How to handle VirWox transfers and invoices that expire quickly?

texts:
I would like to withdraw a moderate amount of Bitcoin (equivalent to a few tens of USD) to pay the subscription to an online service.

I tried to use the "Request Withdrawal" command on the VirWox site, but it resulted in a message notifying that the Bitcoin transactions are only processed after a 48 hours period.

The invoice provided by the online service I want to subscribe to becomes expired after 15 minutes ; at least it is what is displayed on the pay site page I was redirected to (bitpay.com).

Is it possible to proceed to such a transaction directly from VirWox ? Or should I consider an other method ?

Thanks in advance for all suggestions (also please excuse my inexperience about the subject).


texts: Using CryptoCurrencies as a transfer method throughout Australia and Europe

texts:
I have read both this questions:

Can I easily use Bitcoin as a inexpensive way to transfer my money into another currency?

Does it make sense to use BitCoin to transfer money to yourself internationally?

Which both do answer yes to the questions, both answered by @Murch and others ofcourse.

Those questions where done a long time ago, and I'm sure things have changed and improved.

The situation is: I have my cousin in Australia, where he has money there. We would like to transfer it to Euro and I thought we could do it using Coinbase.

Could we just exchange the money to ETH or BTC with AUD and then once in Europe transfer it to a Bank here.

Would that be cheaper than using transferWise or throughout bank transaction? (As far as I can think of, it would be only Coinbase fees on deposit and currency exchange which might differ... Or maybe something else)

We don't actually care about the amount of time that we spend with the transaction.


texts: First step in understanding lightning network

texts:
I'm checking https://lightning.network/ and first paragraph of explanation says:

  Bidirectional Payment Channels. Two participants create a ledger entry
  on the blockchain which requires both participants to sign off on any
  spending of funds.

What does this step mean.
Is this ledger entry a transaction?
Is this ledger entry actually one broadcasted multisig transaction signed by both parties that ends on the blockchain?
Or two parties broadcast two multisig transactions, or two regular transactions?
Can you give a numerical example?

  Both parties create transactions which refund the
  ledger entry to their individual allocation, but do not broadcast them
  to the blockchain.

After the first step above then each party crate a regular transaction to refund what? (Can you continue on numerical example above)

  They can update their individual allocations for
  the ledger entry by creating many transactions spending from the
  current ledger entry output. Only the most recent version is valid,
  which is enforced by blockchain-parsable smart-contract scripting.
  This entry can be closed out at any time by either party without any
  trust or custodianship by broadcasting the most recent version to the
  blockchain.


texts: How do I export a private key from my Bitcoin-QT wallet if the wallet isn't synced?

texts:
I started syncing a bitcoin-qt client, and had somebody send me funds to an address generated in the client.

I then stupidly decided to speed up the syncing process and downloaded a torrent of bootstrap.dat which I loaded into the client.

Now the client is not syncing.

I still have the public address that I had the funds sent to, and I still have the wallet.dat

I would like to get the private key out of the wallet and then import it into an online wallet to at least get these funds before I start again with a local wallet.

Can this be done?

nb: In the client the debug window option is greyed out and cannot be selected.

thanks!


texts: I know that in a transaction, the difference between the amount and the sum of the outputs is the implicit transaction fee, but how do the miners that verify the block containing that transaction actually get access to that fee as UTXO?


texts:
I started to mine BTC recently with my single 7970, and I'm getting 590MH speed on it. Using some BTC profit calculators that I've found on the internet tell me I could earn ~$300-400 worth of BTC annually. Since I have only one PC that I use for work and gaming I can't have it mining all the time, so I'm considering getting an ASIC. I've been looking for information this whole morning and I haven't found a definitive answer on which ASIC I should buy, or should I buy one at all.

I've read some threads that say that the arms race for mining equipment has gone too far to actually be profitable and trading BTC is a better choice, is this true?

Currently I'm looking at BFL products, namely the 5 GH model since it's really affordable at $270, but reading about the mining difficulty rising contantly I get the feeling that this device will become obsolete pretty soon (right?). The next product that I'm considering is the 50GH model priced at ~$2500, which seems to pay itself back and net a nice profit, at least according to the online calculators.

So here's my bombardment of questions: Should I even consider getting the 5GH device? Does a $2500 ASIC REALLY give me a ROI and profit if I order it today (they seem to be in stock)? Can I still use my GPU occasionally to mine alt-coins to trade the for some BTC? Is it a good ivestment to buy BTC, say $50 each month, will it add up in the end?

Any advice is much appreciated :)


texts:
I want to get rid of an old computer, but I checked it for bitcoins, because I knew I tried to mine in the past.
If found this

[img]https://snag.gy/YjCtkI.jpg[/img]

wallet.dat file from june 2011

among with some other files like

__db.001 etc.

blk001.dat

db.log

I'm just curious if there are some coins in it. But I dont know how to access it.
So my question is :
Do I need to download an mining program and sync with the the complete blockchain ?
Anyone an Idea where I can find instructions what to do?
And anyone knows where all these files are for?


texts: Retrieve old addresses with coins that were given away for free to friends and family?

texts:
Looking for a solution where if I wanted to give away bitcoins or other coins to friends and family for free and being able to retrieve them back if they don't claim it or move it.

Many times I gave away a few cents worth of btc a few years ago to friends and family, now those cents are worth a few dollars. Some of them didn't take it seriously and just lost the keys that I made for them on paper wallets.

Has there been a solution to solve this reoccurring problem when introducing newbies to bitcoin?


texts: Can free bitcoins from faucets be actually spent?

texts: Suppose that I have a wallet with 0.001 bitcoins, from dozens of micro transactions (6000 satoshi in average). That means if I want to spend them, it must be concatenated and the transaction fee would be higher than the actual value?


texts: Sending bitcoin from Bitcoin-QT v0.6.2.2 wallet

texts:
I bought a couple of bitcoin in 2012 where they languished on my successive Mac Book Pros in a Bitcoin-QT v0.6.2.2 wallet.  I now realise they are worth - ahem - something!  The wallet still fires up even though it is still calls itself a beta wallet and so I thought I would first try to send my lovely bitcoin to a new and glossy Exodus wallet.

Now being completely new to this I got my receive address for my Exodus Wallet and tried sending 0.1 BTC to my Exodus wallet. Eventually (maybe 5 hours later) it showed it had arrived but with zero confirmations. This first transaction still shows with 0.1 BTC "Pending" in the Exodus Wallet (sent Friday Dec 1st 10.04.10 PM).

I realised I had not included any fee on this first send but  I didn't see anything I could do about that.

Anyway I then sent the balance of BTC in my Bitcoin-QT wallet, but this time included a 0.0004 BTC fee to the same address.  But, 34 hours later it does not even show it having arrived at the Exodus wallet.

Now I really do not know what to do.  I assume if I leave my Bitcoin-QT wallet up and running it will keep broadcasting the transactions and so they may never disappear. So I have quit the wallet.  But suppose I leave it for a few days. If I fire up the wallet then I assume it will broadcast again and I will be back in the same situation?  I could start it up offline and restore from a backup I did just prior to sending the first transaction - I guess that would cut out the re-broadcasts.  Would that be the thing to do?

The Bitcoin wallet reports that the Transaction Ids are:

(Second transaction with 0.0004 BTC fee):

60efa66a8aef482cc3f2ce2ae348427e74feb12db91b579ed4c7ea955fbea0bf

(First transaction with fee not added :-(:

a0a70213c2e94119357cdac865e404e1ca6f44cf40a4acf9a6e272d4f0dd3f21

However when I put those into https://blockchain.info/ I am told the transaction does not exist. The same with ViaBTC Transaction accelerator.


texts: How to get all cryptocurrencies real-time statistics with no limit and free?

texts:
How can we get almost all real-time information of cryptocurrencies (rates, transactions, live prices, blocks info, wallets, etc) for developing new cryptocurrency statistics and exchange reference (like Binance)?

We can use blockchain.com's API for BTC and LTC and some other references like chain.so, block.io etc, but what we need to get all stats for all cryptocurrencies?

I mean how Binance getting this bunch of information? and where can we get them too?

I know there is some website that sell these information and their own APIs but how they got these? and actually how can we get this bunch of information freely?


texts:
I went through the original paper by Satoshi, which outlines the Bitcoin protocol. However, the paper is a high level overview of Bitcoin, and does not specify important parts of the protocol.

Who specified the details of the Bitcoin protocol? Which person or group is in charge of defining the standard of the protocol as of now?


texts: The Bitcoin scripting language has OP_SHA1 as one of its opcodes. However, I'm not able to find any usage of this opcode (it is not used in any standard scripts nor in any other procedures such as block hashing). So my question is: is sha-1 used anywhere in Bitcoin?


texts: Beginning 2017 what estimate of individuals own bitcoin?

texts:
How many different individuals in the world own bitcoin?

I.e. John owns .5btc, Michelle 300btc, Al 4000btc : the answer would be 3.

I am interested in the percent of the global population that owns bitcoin as it would be a good indicator of the potential (and value) further for bitcoin as it is educated to more and more people and eventually reaches mainstream (hopefully).


texts: Bitcoind could not locate RPC credentials but rpcuser and password are set

texts:
I installed bitoind and synced it. But when i'm trying to connect from my php website i getting:
Unable to connect to http://user:password@my.bitoind.server.ip:18332/.
Also when i'm trying to see password through command

bitcoin-cli -stdinrpcpass getblockchaininfo

it returns

could not locate RPC credentials. No authentication cookie could be found, and RPC password is not set.  See -rpcpassword and -stdinrpcpass.  Configuration file: (/blockchain/.bitcoin/bitcoin.conf).

My bitcoin.conf file is setted and works nice

rpcuser=USER
rpcpassword=PASS
testnet=0
daemon=1
rpcport=18332
rpcallowip=*
server=1
datadir=/blockchain/.bitcoin
txindex=1


texts: How to use block and transaction hashes for generating simple stochastic chances?

texts:
Many online Bitcoin gambling websites use the block chain info to prove fairness. Most of them use rather complex algorithms for this with pre-published secrets.

What most of them basically achieve: Convert a block hash or a transaction hash to a number in a certain range.

What is the simplest way to do this in a fair way, verifiable by everyone? I would like to focus mostly on using block hashes, which are the least manipulable.

With a simple way I'm looking for either a very simple mathematic way to do so or either a library which can do it for you.

I understand that predefined secrets are required when transaction information is used, because these are easy for users to manipulate. Block information, on the other hand, is far less easy manipulable. If you want to generate a block with a hash that would make you win in the game, you would make the standard block generation problem even more difficult and you will have to do solo mining  which is already quite hard when doing regular mining.
So, are these secrets also required when using block information?

Note that I am an engineering student myself so I will probably understand much cryptographic and mathematical terms, but the purpose of this question is of course to receive an answer that everyone can understand.


texts: Why doesn't basepoint G of Secp256K1 seem to be on the Elliptic Curve?


texts: Practical tips for validating raw transactions

texts:
I have a protocol that creates a raw signed transaction that is then broadcast to the network. The transaction aims to send X BTC to a single address Z. The transaction is created with the help of bitcoin core.
In the past I've seen a few instances where people got themselves in trouble by creating unexpected transactions, for example by paying 90% of the UTXO's value as a mining fee or the like.
Therefore I was wondering if someone could advise on procedures/tips for the following

Given a raw transaction T sending X BTC to address Z, how to validate the transaction accomplishes this gracefully?

The idea is that before the broadcast one issues an additional decoderawtransaction and checks that everything is as intended. I would like to hear tips on what one should check for at this point.
I understand the question itself is a bit vague but I'd like to hear any kind of feedback on what to look for in the output of decoderawtransaction that might be telling something is either not right, or validate that

The transaction is sending X BTC to Z,
What the exact expenditure (X+fees) is,
That the change is sent to the right (i.e under the wallet's control) address.


texts:
I want to create a bitcoin wallet executable file in Ubuntu with all its dependencies. So when use that file from some other system it will work perfectly.

How I make a portable version of Bitcoin for Ubuntu?


texts: If I received two blocks at the same time, which one should I choose to mine the next block?

texts:
Is the situation could happend?

If true, What's the role? Is the Bitcoin pick one block randomly?


texts:
What I did is put a password on word document and put the seed words in there and then put the file in google drive.

I can't think of any way I can lose it. I can't think of anyone stealing the money either without knowing my password.

The Electrum wallet is also encrypted with the same password.

Are there any ways to improve my security?


texts: Zero-BTC transaction fees, service-specific mining pools and external compensation

texts:
Bitcoin is a network that is proven to be stable, but if you want applications on top of Blockchains you have to play by the rules of the system. For notary use cases (for example), where you would store a document hash on the chain, it might not be beneficial to charge a transaction fee for issuing a document, since you would want to encourage your users to create content and perhaps charge people who want to verify the information instead.

Let's say you build a mining pool that accepts zero transaction fee that owns and maintains a certain percentage (let's say 0.1%) of the global Bitcoin mining power. Let's also assume the mining costs (energy, hardware depreciation, etc.) are not an issue (for now).

Can a transaction that offers zero fees target this mining pool? (I assume yes, through a tag in metadata perhaps)
Could this mining pool filter staged transactions by this tag?
Can the mining pool, if it owns 0.1% of the global mining power guarantee the confirmation of the transaction within a certain period of time? (1hr, 10 hrs, 1 day, 1 month, 1 year?)
Is there any example out there that do something similar and use an external mechanism how to compensate mining costs?


texts: Is selfish mining still an option with compact blocks and FIBRE?

texts:
The selfish mining strategy relies on withholding a block to build on it in private. When the honest chain publishes a block, the attacker immediately broadcasts its own withheld block in order to try to replace it.

Today, most miners are connected via FIBRE and the general network has compact blocks to exchange compressed blocks. The delay until a block is known to the complete miner community is thus much smaller than in 2013. It seems that under the "first seen paradigm"  selfish mining becomes a losing strategy for blocks with such short relay times.

Is it correct to conclude that selfish mining is a theoretical attack now?


texts: Is mining something specific of Bitcoin?

texts:
I am very new to the world of cryptocurrencies (I first read deeply about them today) and I've just discovered the concept of mining. Everything that I've read so far applies to Bitcoin but I know that there are a lot of different cryptocurrencies. So I was wondering if mining also exists for other currencies.

Is mining something specific of bitcoin or is it possible to mine different cryptocurrencies? If so, is the process different than the one used to mine bitcoins?


texts: If a transaction gets a minimum of 3 confirmations, does that mean that the BTCs have reached the destination address? I have a case where the transaction has gone through multiple confirmations but the order status on the payee platform is still showing "unpaid".


texts:
I am a little puzzled about how miners choose transactions, are the people who want to transfer Bitcoin sending their transaction to miners asking them to validate them, or are they put somewhere and then the individual miners can aggregate the ones they like?
I tried to find some information on google about this but it didn't really illuminate the problem well enough for me.


texts: Are the addresses in my Wallet client considered to be all as only 1 account or wallet?

texts:
I'm using the Bitcoin Wallet Client and I've noticed that you could create as many addresses as you want. But I also noticed that there's only 1 Total Amount for the wallet. So does that mean that you could have multiple addresses, but all of that points to same single wallet?

More:
And so, if my wallet contains several addresses, when I would like to send coins to another address of another person, do I need to create another address to send the coins? Or do I need to send coins one by one from each address? Or could I just send from one address since all of the addresses are in the same wallet?


texts: What are the effects of leaving Bitcoin-QT open?

texts:
I'm using bitcoin-qt at the moment, and at the bottom of the download page it says:

"Do you have a computer that you keep switched on all the time, that's connected to the Internet? You can help the community by simply running the original Bitcoin client on it. The original client is more resource intensive and will take a complete day to synchronize. After that your computer will contribute to the network by checking and relaying transactions."

Clicking the "original bitcoin client" just takes me to the same download as clicking "bitcoin-qt" (http://bitcoin.org/en/download). Does this mean leaving it open is mining, or doing something else? (or does it even use my resources?)


texts: Make payments Lightning without Invoice?

texts: The Lightning-RFC defines, in BOLT #11, an invoice protocol for proof-of-payment. While this is a pretty cool feature, I was wondering if it would be possible to make a payment without such invoice. That is, with the origin node defining a payment hash etc.


texts: I tried to send my Bitcoins to my wallet earlier but have managed to miss the last two digits off the address when copy/pasting. The payment was sent straight away but has obviously not arrived, is there anything I can do? I have a horrible feeling I just lost all of my money to a typo, any help will be gratefully received.


texts: Does listsinceblock list all transactions, or only transactions my wallet is interested in?

texts: Wondering if I call listsinceblock "", will I get all transactions that ever occurred on the blockchain regardless of whether my wallet was party to it, or will it only be a list of transactions relevant to my wallet (things I've sent/received/have a private key for at least one side of) ?


texts: Why is P2PKH used instead of the simpler P2PK?

texts:
If elliptic curve cryptography is secure enough to be able to give away a public key without fear of anyone being able to calculate our private key from it, what's the reason for hashing our public key for use in P2PKH?

In other words, what's the benefit of a more complex system for locking and unlocking bitcoins, if a simple P2PK transaction is secure enough?

I'm not against extra security, but why is it not considered to be redundant?


texts:
I have some Bitcoin from before the Bitcoin Cash fork, and am pleasantly surprised to learn it has some significant value.

I believe there have been a number of other forks as well.  But I don't have a list, or know how to research it, other than general Googling.

Is there any canonical list of forks with information such as Date of the Fork and current value?


texts: Are there any legal implications when using localbitcoins.com?

texts:
You can get BitCoins for under 100 bucks via CoinBase and there are people on LocalBitCoins who are advertising offers to buy BitCoin for over 100 bucks.  The spread is around $10; so I was considering arbitraging.  Are there any laws that would apply to transactions conducted through the LocalBitcoins website that I might not be aware of?  I'm thinking of a situation where a person you sell BitCoins to might, unbeknownst to you, turn around and do something illegal with them, and get caught.  Would the seller of those coins some how be in the wrong in the eyes of the law?

Edit: I'm looking specifically for applicable US laws it would probably have to be several thousand bucks a week to be worth the time.


texts: Did not recieved bit coin due to unconfirmed transaction since 2 days

texts:
I sent 0.305*** some bit from my block chain wallet to zebapy wallet.
Since 2 days I did not received any amount and also I can see in block chain information that 0 - pending confirmations. (0/6).

Can anyone help me how to get my money back?

https://blockchain.info/address/38QFMgBBTX8j8Zn36nuVJnaHWnWgmGmHdU


texts: International shipping times for Butterfly Labs ASIC hardware

texts:
The Butterfly Labs FAQ says they use USPS for shipping (except for Mini Rigs), and displays the options "Standard" and "Express" during the checkout process:

However, the USPS website appears to offer "Express" shipping (1-3 business days) and "Priority" (6-10 business days) for international shipping.

I'm sure people out there have received FPGA devices internationally from BFL in the past, probably with the same international shipping options. Can anyone confirm that delivery times of BFL hardware are equivalent to the two options I found on the USPS website?


texts:
Can anyone please tell me if my procedure is correct and enough.
I've always heard and read that I must disconnect from the internet when creating Electrum Wallets, to keep away from hacks, viruses, malware or having my bitcoins stolen.
I have created electrum wallets and bitaddress paper wallets yesterday. Though I dont know much about its technicalities, I just followed simple procedures I've read online.

downloaded electrum exe installer and bitaddress (from github)
save them in my usb
disconnected my laptop from the internet
uninstall and reinstall Windows 10 (I have windows installation files too, in my usb)
created Electrum wallet, write the seed in a paper. save the wallet file in my usb.
created bitaddress paper wallet, write the Public Key and Private Key in a paper (not print). have checked the spellings, capitalizations multiple times.
uninstall and reinstall windows 10 again, scanned my usb, then connect again to the internet.

Thanks for any advice / clarifications,
Elena


texts: What reasons are there to mine and support Litecoin?

texts:
There are many examples of Bitcoin being accepted as a means of exchange in online transactions.
I haven't found any such examples for Litecoin.

So, what is the value in LTC mining? What is LTC's purpose if you can't buy anything with it? Do people believe that LTC is in the process of becoming a currency that will one day be accepted in the same online transactions as Bitcoin?


texts: How can I create a multi signature 2-of-3 transaction?

texts: Can somebody help me with step-by-step list of how to create a multi signature 2-of-3 transaction?


texts: Is there any "added value" to run a full node behind a router or firewall?

texts:
By reading different questions/answers on the bitcoin full node subject, I am still wondering if there are any "added value" in running a full node as an individual.

Most of the "everyday life" people don't know much about computing and network. They don't know anything about NAT, DHCP, router configuration, process, daemon, etc. They don't necessarily want to bother with config files, don't care about command lines or complicated options and so on. And they live and sleep very well without knowing that!

So I am wondering if there are / what are the benefits in running a full node as an individual:

benefits for the network

If I run a full node without activating NAT on my Internet access router/modem (and then not being able to accept new connexions), is it pointless? Am I doing good or bad by doing this? Am I securing the whole thing for example? Other benefits?
benefits for the individual

What are the benefits for the individual who runs a full node at home, behind the ISP router/modem? Let's take the assumption that this individual is the owner of some bitcoins (so he/she has at least a slight interest in the domain). Will he/she benefits from faster transaction for example? More secure transactions? Other benefits?

Could someone clarify that for me?

Thanks


texts: Removing Bitcoin from my phone to secure storage

texts:
I am using the following Bitcoin wallet for Android:

https://github.com/bitcoin-wallet/bitcoin-wallet

My device is encrypted and I have encrypted backup files on Google Drive.

However, I'd like to get my coins off my phone altogether, just in case its stolen and the UI is still accessible. I'd like to keep a small amount on my phone, and top up that balance every now and then.

What's the best way to do this?

I think I need a separate "long term" wallet, but that's just moving the same problem to somewhere else.

Is a hardware wallet the only way to go here?


texts: How does an SPV wallet use the headers that it downloads?

texts: My understanding is that an SPV wallet downloads "headers only". These headers are not enough to get a UTXO set, so it has to rely on another data source when it comes time to move bitcoin. If thats the case, then why does it even need the headers?


texts:
Recently I started analyzing the UTXO set data that every full node stores in chainstate folder (a LevelDB database).

By looking into the code you can learn more or less how the data entries are formatted. However, to save as much space as possible, some of the data is compressed and encoded as a varint.

How data is compressed can be found and also analyzed in the code. However, I'm struggling with understanding how the varint encoding/decoding is performed. According to the developers guide, the class responsible to do so is CVarint, and I've been able to trace down the method that I think is doing so. However, since I don't know the format the data is encoded I'm not able to understand what it is doing.

Does someone have a clue about how the stored data is formatted?

Clarification: I'm referring to the CVarint format that is used in UTXOs along the Bitcoin Core, not to the varint format that is used to encode information in txs scripts.


texts: Receiving `error: {"code":-25,"message":""}` on sendrawtransaction with v0.9.3


texts: In MuSig-DN why not use a truly random number for the nonce instead of a pseudorandom function?

texts:
In MuSig-DN why not use a truly random number for the nonce instead of a pseudorandom function (PRF)? If the nonce space is big enough it would never be reused.
This question was asked by emzy on Twitter.


texts: Can private keys remain offline for their entire life?

texts:
I am new to Bitcoin and this question is based on 3 assumptions that may be incorrect.

Assumption 1:
If I understand correctly, the Bitcoin address is generated algorithmically independent of the network, so I should be able to create a public address and private key offline correct?

Assumption 2:
I can receive funds through the network using my public address without ever having to make my private key known to anyone correct?

Assumption 3:
Now when it's time to spend my funds, offline I can create a Bitcoin transaction authorizing the transfer from my address to another location and sign it with my private key entirely offline. I can then transfer that transaction to a separate computer with internet access and then publish that transaction to the Bitcoin network to be mined/verified in the blockchain?

Conclusion:
If all 3 points are true then I should be able to keep my private key from the internet for it's entire life correct?


texts: Convert back from BTC into a local currency, efficiently

texts:
I receive rent income in the US. I'm using coinbase.com to convert from USD into BTC, with no problems.

I will be traveling outside the US, so I would like to convert back from BTC into a local currency. (I'm going to Ecuador; there are several exchanges but they seem set up for people to buy BTC.)

What I want is to convert from BTC into the local currency. What is the most efficient way to do this? (I may need to do this several times, which is why I'm interested in doing this efficiently.)

How should I set it up?


texts: Bitcoin-qt taking forever to acquire the blockchain

texts: I thought that this was the old days when it took forever for bitcoin core to acquire the bootstrap but it looks like it's still the case. I basically ran the program for 2 hours and I'm still under 10h. Any idea on how to fix the problem or download the blk files elsewhere ? Why can't I find the equivalent of the bootstrap as a torrent ?


texts:
I am running lightning with the LND implementation and a full node. Nevertheless, I heard that it is possible to use Lighting in pruned mode.

How is this possible?

I read in the LND install documentation that you need the -txindex flag:

  In order to run lnd with a bitcoind back-end, the bitcoind instance must be configured with --txindex just like btcd above.

In the Wikipage of Bitcoin it says for pruned mode:

  This mode is incompatible with -txindex

I also read here and here the same arguments.

Is this outdated or is it not possible to use prune mode in lightning?


texts:
I have seen this question pop over a few times but I did not find an answer I could understand. This is the scenario:

I created a BCH wallet, mistakenly thinking it was a BTC one.
I bought BTC and sent to the BCH address
Realizing the mistake, I created a BTC wallet using the BCH passphrase.

Is what I did correct? Am I likely to see my bitcoins? Should I do anything else? How can I check where the purchased coins are?


texts: Bitcoin-core 0.15.1 gettransaction showing wrong fee for some transactions

texts:
What makes me wonder, this happens just for some transactions

Take a look at this transaction:
20179d0d2fba68b2ca82ab8cc5faa39ced73324af6b90b6505cca2c3d65102a6

As you can see inputs/outputs fee is: 0.001 BTC

In bitcoin-core gettransaction

bitcoin-cli gettransaction "20179d0d2fba68b2ca82ab8cc5faa39ced73324af6b90b6505cca2c3d65102a6" true

Returns this result:

Array
(
    [amount] => -105.21509845
    [fee] => 105.11519845
    [confirmations] => 78
    [blockhash] => 0000000000004caf7faef44b3cd20424b04e8044a8d323064e1fca6864b96cb9
    [blockindex] => 18
    [blocktime] => 1517902289
    [txid] => 20179d0d2fba68b2ca82ab8cc5faa39ced73324af6b90b6505cca2c3d65102a6
    [walletconflicts] => Array
        (
        )

    [time] => 1517902198
    [timereceived] => 1517902198
    [bip125-replaceable] => no
    [details] => Array
        (
            [0] => Array
                (
                    [involvesWatchonly] => 1
                    [account] =>
                    [address] => 2N2QxAHtCMMDpxTxuNNNHvDh4burprspWPN
                    [category] => send
                    [amount] => -0.1625
                    [vout] => 0
                    [fee] => 105.11519845
                    [abandoned] =>
                )

            [1] => Array
                (
                    [involvesWatchonly] => 1
                    [account] =>
                    [address] => 2MtuDKij5ueE4C9D5wjA3Ft9bkjMJByxr4d
                    [category] => send
                    [amount] => -105.05259845
                    [vout] => 1
                    [fee] => 105.11519845
                    [abandoned] =>
                )

        )

But with this transaction everything is fine:

20179d0d2fba68b2ca82ab8cc5faa39ced73324af6b90b6505cca2c3d65102a6

bitcoin-cli gettransaction "20179d0d2fba68b2ca82ab8cc5faa39ced73324af6b90b6505cca2c3d65102a6" true

Result:

Array
(
    [amount] => -1.049
    [fee] => -0.001
    [confirmations] => 136
    [blockhash] => 0000000000000fd2e83cc1a8145b055a1a33ea996f7a93578197a48848201a5b
    [blockindex] => 1
    [blocktime] => 1517898674
    [txid] => b0ad2f8047b6bfc6a0da4947ec7cda59ccf423df2d24dcbf2996042cdf45c10a
    [walletconflicts] => Array
        (
        )

    [time] => 1517898650
    [timereceived] => 1517898650
    [bip125-replaceable] => no
    [details] => Array
        (
            [0] => Array
                (
                    [involvesWatchonly] => 1
                    [account] =>
                    [address] => mxKPZ2rnev5odtFTqS273946YgQfY7H6E5
                    [category] => send
                    [amount] => -0.0001
                    [vout] => 0
                    [fee] => -0.001
                    [abandoned] =>
                )

            [1] => Array
                (
                    [involvesWatchonly] => 1
                    [account] =>
                    [address] => 2NG1QAAFsM71L7YwVxkjSeMbKYpW6KFURXs
                    [category] => send
                    [amount] => -1.0489
                    [vout] => 1
                    [fee] => -0.001
                    [abandoned] =>
                )

        )

to get the fee of that type of transactions we could do:

105.21509845 (amount) - 105.11519845(fee) = 0.001

But why bitcoin core doesn't do it and why it's only for some transactions?


texts:
Someone sent me 1000$ but when I pasted my adress this happen:

15nTPsVp3EGk78FUGcmAyqCnFCsfv6shLb (mine)
15QrWeM7HcJz8haNQUtq6KU23GDSHn8xxx (hacker)

It's been 6 hours and still unconfirmed on blockchain and it's not on blockexplorer.

Is there anything i can do or sender to cancel the trade?

I've watched videos about how to double spend but I'm afraid it will help the transanction go through.


texts: Hypothetically, if it were a well coordinated NSA-type shut down and ALL ISP's suddenly blocked port 8332 (major ones anyway), how would the Bitcoin system immediately handle it?


texts: Dump results from bitcoin-qt debug console to file

texts: I would like to issue some commands in the Bitcoin-qt console and save their output to a text file (ideally, filter it before saving). Is there a way to do that, similar to how I would use grep and > in a regular Linux terminal?


texts: Can't find an API which gives me a full list of cryptocurrencies ordered by market cap

texts:
I need to know the top-10 crytocurrencies ordered by market cap so I am looking for an api that returns a list of coins ordered that way.
Does anyone know?


texts: Bitcoin Core for Mac not syncing, can't access private key to export coins to other wallet

texts:
Wondering if you can help me guys, I'm new to using bitcoins and recently downloaded Bitcoin Core to my MacBook. I stupidly sent bitcoins to my wallet without realising i had to sync first, but it's been syncing for a week now and still has 1 year 46 weeks to go. It's barely altered in 2 days so i've given up waiting and have been using blockchaininfo's online wallet, so I want to get those bitcoins transferred to there if possible.

I've read the threads about exporting the private key, but the problem is I don't know the passphrase to access it as i was never prompted to create one, I just installed it and started syncing. Also, Blockchain's 'desktop sync' feature that people have mentioned doesn't appear anywhere in my account, so i can't do that either. Is there any other way of doing it?

Thanks


texts: When building bitcoind from source, how to specify stable build?

texts:
I managed to build bitcoind on arch linux after downloading the source from github, but after running bitcoind getinfo command, I am told:

  "errors" : "This is a pre-release test build - use at your own risk -
  do not use for mining or merchant applications"

How can I remove that message and use a stable build, instead of the pre-release one I downloaded?

I assume I have to do something with the information found here: https://github.com/bitcoin/bitcoin/tags


texts:
I am trying to get transaction fee for sending all btc to another account.
I use estimatesmartfee to get tx fee, I have total btc amount of 0.0195btc, so I pass 0.0195, but I get JSON integer out of range (code -1)


texts: Bitcoind stops downloading the blockchain

texts:
I have bitcoind running on Ubuntu 16.4 VPS.
The problem is that it just randomly stops downloading the blockchain and when i run

bitcoin-cli getblockcount

it returns in begining the block count - 165572 and after 10 minutes its look like its crashed and show me 0.

any ideas?


texts: Which country has the highest number of Bricks and Mortal merchants who accept Bitcoin per Capita?

texts:
I have seen many online directories of Bitcoin merchants but fewer bricks and mortar directories.

Is https://coinmap.org comprehensive? The great majority all of the listings are for North America and Europe?  I hope that listings are being missed in countless other parts of the world.

Many say the 3rd world is potentially the largest beneficiary of blockchain technology but the current statistics are not painting a bright picture for adoption in most areas.


texts:
I have built a base-58 encoder using this formula: https://www.youtube.com/watch?v=GedV3S9X89c&feature=youtu.be

Is there a smarter way to encode/decode with base-58?

I read somewhere that you need a bignum library which I use Boost for.

My goal is to convert between these two:

008D4D508F5BF2C28B20A3863405F05D3CD374B045E4B316E7
1Dt8ty59tU9LkrXG2ocWeSzKFAY8fu6jga

Which so easily this website do: http://lenschulwitz.com/base58

I know bitcoin source code have a base-58 encoder/decoder, but I do not know how to implement it successfully.


texts: I've noticed the recently solved block hashes have started with a number of zeros (8 last time I checked). Couldn't we just tell our mining hardware/software to assume the first few digits are in fact zeros and give us a head start?


texts: Unconfirmed BTC transaction / TXID doesn't exist?

texts: I recently tried sending some btc to coinbase.  In a hurry I did not put a transaction fee.  I've tried to explain to their customer support what is going on.  I offered to charge me a fee through my wallet on coinbase to do a pay for parent protocol. Their lack of understanding is making me worry.  I tried using ViaBTC.  I put in the transaction ID and they said the TXID did not exist.  Any suggestions would be appreciated.  Its approaching 7 days now.  Thank you.


texts:
2 Parts to this.

1st - What is a typical winning block (I get coins) generation time when running on testnet.

Ive done numbers with calculators and all that but given I cant work out accurately what the 'normal' difficulty for testnet is, I dont know where in the range of numbers I've seen is right to consider normal.

2nd - How can I be sure that I'm actually mining, not that I'm just computing useless hash after useless hash thats getting sent to a black hole somewhere?

So far, using 2 machines CPU mining on testnet (and even trying unsuccessfuly for an hour to get GPU mining to work as well, figuring that if it worked, i can just stop this after a few minutes and get on with my work) to generate a bunch of coins for testing some bitcoin related transaction handling software.

I have managed to generate zero bitcoins.

1Mhash/s and 500Khash/s for over an hour each. Plus the hour trying various gpu mining things on and off. And no coins. I'm confused & wondering how to debug this. Since I can send and receive bitcoins without issue.

I gave up trying to testnet mine since I was able to use a generous faucet to borrow some for testing. But the geek in me is very very irritated at not having worked out what was broken and fixing it. And now I'm in the situation where I'd like to put my own machines horsepower back to work mining on the testnet in order to speed up the transaction confirmation times, even if its not by much, so im stumped.

Edit -- More specific hashing figures. I lowballed my numbers a fair bit.

Laptop [ Macbook Air ]

CPU [ 2Ghz i7 ] Using:

bitcoin-qt internal miner ~1.5Mhash/s over ~4hrs

Desktop [ Custom ]

CPU [i5-2500K@3.3Ghz] Using:

bitcoin-qt internal miner between ~4.2Mhash/s and 2.3Mhash/s over ~2hrs
GUIminer/poclbm OpenCL ~1Mhash/s over ~2hrs

GPU [ AMD 6900 Series GPU-Core@830Mhz Mem@1300Mhz ] Using:

poclbm OpenCL ~325Mhash/s over ~30min
DiabloMiner ~325Mhash/s over ~30min
cgminer wouldnt run, kept crashing on start, debug log didnt have any clear cause, the log actually looked like it died half way through trying to say something. The last entry was something like 'Tha'

So, yeah all that and no coins.


texts: A limit on privpub key pairs in a wallet

texts: Is there a limit on the number of private/public key pairs one can have inside a wallet? For instance if I have, say, a 1M transactions could I have a million unique bitcoin addresses...each address created with a different private key?


texts:
I go to:

https://mtgox.com/users/login

Click on "Forgot your password?".   Enter "User Name or email".  Click on "Recover my password".

Nothing happens.  They say " We will email you a link to reset your password."  But they don't.

Is there some way to get past this?  Is there some way to contact someone who maintains the site about this?


texts: Wallet takes way too much time to keep up to date?

texts:
I would like to start using bitcoin more for day-to-day transactions. However, it takes way too long to keep my wallet up to date to be practical. I am using Bitcoin Armory, though I have had this problem with every bitcoin wallet software I have tried so far.

I don't have a super powerful machine, 64 bit OS, 8 core CPU @ 1.6 GHz each, 6GB RAM, Radeon 6570m GPU, no SSD. My laptop becomes noticeably slower and almost unusable when the bitcoin software is running. Thus I have to turn it off when I need to use my computer. But if I leave it off for 12 hours, it takes on the order of 12 hours to resync.

I feel like I MUST be doing something wrong. Does everyone using bitcoin really have a 24/7 dedicated box (possibly in the cloud) to keep their wallet up to date? This isn't practical for me at all, especially since it takes longer and longer to sync each time as the number of transactions per day increases.

Note: for security reasons I am not willing to use an online service that holds my wallet.

How can I make using bitcoin more practical? I have heard about using clients that don't download / maintain the full blockchain, but doesn't this defeat the purpose of being able to verify the transaction ledger myself?


texts: Bitcoin Core Multi-wallet limit to 333 wallets

texts:
Bitcoin Core 0.15.1 has Multi wallets support:

In the bitcoin.conf we can add multiple entries of:

wallet=wallet-1.dat
wallet=wallet-2.dat
wallet=wallet-3.dat
wallet=wallet-4.dat
...
wallet=wallet-350.dat

When Bitcoin Core starts, if the wallet file does not exists it will create it. which is great for our needs.

However, it always crashes on the 333 wallet. with db.log error:

Lock table is out of available locker entries

And debug.log:

2018-02-13 14:47:05 init message: Loading wallet...
2018-02-13 14:47:05 nFileVersion = 160000
2018-02-13 14:47:05 Keys: 21 plaintext, 0 encrypted, 21 w/ metadata, 21 total
2018-02-13 14:47:05  wallet                   36ms
2018-02-13 14:47:05 setKeyPool.size() = 20
2018-02-13 14:47:05 mapWallet.size() = 0
2018-02-13 14:47:05 mapAddressBook.size() = 0
2018-02-13 14:47:05 init message: Loading wallet...
2018-02-13 14:47:05

************************
EXCEPTION: St13runtime_error
CDB: Error 12, can't open database wallet-333.dat
D:\BitcoinCore\bitcoin-0.16.0\bin\bitcoin-qt.exe in Runaway exception

I also tried to minimize the -keypool=20 so that the wallets size will be much smaller in size, and the process of loading them is much faster.

I was suggested that this error is because each wallet.dat file is opened in the same BDB environment. The entire environment has a limited number of database locks, and it seems like 333 wallets hits that number of database locks.

The solution (which did not work) is to create a file named DB_CONFIG in the data dir, and put the following lines in that file:

set_lk_max_locks 400000
set_lk_max_objects 400000

By default it is 40000 and now 400000 (ten times more locks available)

But this gave the same results.

I tried also:

set_lg_dir database

With no luck.

I verified this on two different Windows 10 machines with 0.15.1 and 0.16.0. Same result. It always crashes when loading the 333 wallet.

Anyone have a solution to this?

I have put the list of wallets if anyone care to reproduce: https://pastebin.com/8wHD1tL3


texts: How are block interval, block size and effective throughput related?

texts:
I have two questions:

Why does the effective throughput (as defined below) decreases when the block interval is decreased?
How does a reduction in the block size results in maintaining a high effective throughput?

The origin of these questions is as follows.
First, this paper about Scaling Decentralized Blockchains says:

  To improve the system’s latency, we can in principle simply
  reduce the block interval. To do so while retaining high effective throughput,
  however, would also require a reduction in the block size.

which implies that the effective throughput decreases when the block interval is decreased. This results in my first question.

Second, they define effective throughput as follows:

X% effective throughput := (block size)/(X% block propagation delay)

This formula indicates a decrease in effective throughput when the block size is decreased, while their goal is the opposite, i.e. maintaining a high effective throughput (by decreasing the block size). This is what my second question is about.