texts: Are there decentralized bitcoin asset management systems out there?

texts:
Are there any decentralized/shared bitcoin asset/investment management systems out there?

It should be applicable to the following case:

Many peers and nobody trusts each other. But trust is gained by investing bitcoins in that system.
Nobody should be able to withdraw more money, than they invested.

I cross-posted this question on

http://www.reddit.com/r/Bitcoin/comments/1zsjr8/are_there_decentralized_bitcoin_asset_management/

I hope it's ok, if not i'll take the link out of this question.


texts: What consensus algorithm is MimbleWimble/Grin using? Does it use Zero Knowledge Proofs as well?

texts:
Understand that MimbleWimble/Grin is privacy centric.  Does it use Zero Knowledge Proofs to achieve the privacy goals?

In addition, what consensus algorithm is MimbleWimble/Grin using?


texts: Difference between Public Bitcoin Address and Hash 160 Address?

texts:
I know the difference Public Key and the Public Bitcoin Address (hashed version) and why.  But I dont understand why there is a Public Bitcoin Address and Hash 160 Address?

I assume the Hash 160 Address is just another hash of the Public Bitcoin Address?

Can you tell me what exactly the Hash 160 Address is and more important, why it is needed?

Thanks!


texts:
I'm interested in using a pogoplug to run bitcoin. From my understanding, I should be able to connect to the pogoplug from another device (RasPi with AM BEs) and mine on my own. I'm having trouble figuring out what I'm doing wrong -- I've got bitcoin cloned to the plug from github, but in following what it seems others have done,

make -f makefile.unix USE_PNP=-USE_IPV6=0

nets

make: *** No rule to make target `makefile.unix'.  Stop.

Suggestions?


texts: How does Lightning transaction revocation work?

texts:
I've been reading about the Lightning Network, and I feel like I alllllmost understand it, but I can't quite figure out how the revocation transactions are designed so user A can claim the channel's bitcoins if user B tries to post an out-of-date commitment transaction.

From what I understand, revocation transactions (aka anti-cheat transactions) can be posted that will give the poster their bitcoins after 1 week, but will give the other party their bitcoins immediately. What I don't understand is, when an out-of-date revocation transaction is posted by user B, how user A can also claim user B's bitcoins.

Here are some of the best sources I've read for this:

https://rusty.ozlabs.org/?p=450
https://bitcoinmagazine.com/articles/understanding-the-lightning-network-part-building-a-bidirectional-payment-channel-1464710791/

I'd very much appreciate an explanation that helps this part of the protocol make sense.


texts: Is it possible to configure the bitcoin daemon to only broadcast unconfirmed transactions with ZeroMQ?

texts:
Currently, I am running a full node bitcoin daemon configured to publish hash transactions via ZeroMQ (ZMQ). I've been noticing that, as a subscriber to the hashtx topic, there are both confirmed and unconfirmed transactions being broadcasted. I only really care about the unconfirmed transactions. Is there any way to configure the bitcoin daemon (bitcoind) to just broadcast unconfirmed transactions?

There are long stretches of intermittent time, on the order of a few minutes, when ZMQ is broadcasting confirmed transactions, and this behavior is resulting in a "freeze" like state because no new unconfirmed transactions are flowing through (being blocked by the stream of confirmed transactions coming through).

At my application layer, I can filter out for the confirmed transactions, but still, I'd like to stop it at the source if possible.

On another note, why is ZMQ broadcasting both confirmed and unconfirmed transactions? Does this have something to do with the daemon having to update its local copy of the blockchain?


texts: Parse UTXO of a transaction from chainstate

texts:
I'm doing some analysis on the UTXO set by reading from the chainstate database.

I was following the documents given by https://github.com/bitcoin/bitcoin/blob/d4a42334d447cad48fb3996cad0fd5c945b75571/src/coins.h#L19-L34

/** pruned version of CTransaction: only retains metadata and unspent transaction outputs
 *
 * Serialized format:
 * - VARINT(nVersion)
 * - VARINT(nCode)
 * - unspentness bitvector, for vout[2] and further; least significant byte first
 * - the non-spent CTxOuts (via CTxOutCompressor)
 * - VARINT(nHeight)
 *
 * The nCode value consists of:
 * - bit 1: IsCoinBase()
 * - bit 2: vout[0] is not spent
 * - bit 4: vout[1] is not spent
 * - The higher bits encode N, the number of non-zero bytes in the following bitvector.
 *   - In case both bit 2 and bit 4 are unset, they encode N-1, as there must be at
 *     least one non-spent output).

The parser worked fine when the number of UTXO is small. However for the following tx (which have 2501 outputs), it failed:

2540b961f4a0b231db3bc5a23608307394eae037d8afd0462e9b794e02f00000

For the key 'c' + 2540b961f4a0b231db3bc5a23608307394eae037d8afd0462e9b794e02f00000, the (deobfuscated) value in chainstate looks like this:

01907050e140254150443a0c280004...

Where 01 is the version, 9070 is the nCode which tells if its a coinbase tx, the unspentness of vout[0], vout[1], and the length of the following unspentness bitvector for vout[2:]. By looking at blockchain.info, there are 2501 outputs, so there shall be (2501 - 2)/8 = 312 bytes following. However, parsing 9070 as a varint, removing the last thee bits, and +1 only give me 2288 / 8 + 1 = 287. (I got 2288 by (0x90 - 0x80 + 1) * 0x80 + 0x70, which is the MSB-128 varint used in bitcoin protocol.)

Did I missed something here? How exactly does one parse the varint?


texts:
I am trying to develop a program which can create a transaction from scratch and use a private key to sign it. The idea behind is an open wallet where users each has its own private key and the wallet prepare the transaction (amount, destination..) and the user sign it before the open wallet send it.

Thank you


texts: What kind of messages are those used by Bitcore

texts:
When creating a transaction proposal with Bitcore,
the options include a "message" field, both for the transaction and the single outputs.

Are these messages those used by the Bitcoin network peers (like 'ver', 'inv', etc..)?

Where are these messages stored?


texts: Is there any way to send an output to a script which can then only be sent to one of two addresses?

texts:
Is the following scenario possible?

I want to send money to a script. This script will require knowing a private key to spend, as usual, but the script is only valid if the money is being sent to one of two addresses. That is, if the transaction has more than one output, it is invalid. If the transaction's output is a standard script to address A or to address B then it is valid. If the transaction output value is any less than x, it is invalid.

In other words, it seems the scripts serve to validate that you can spend the output, but then the output can be spent however the claimant wants. Is there any way to limit how the outputs are spent? All this without requiring a trusted oracle of course.


texts: Bitcoin disappeared after resetting the blockchain and transactions

texts:
I'm looking for some advice on trying to recover bitcoins.
I transferred some bitcoin to my multibit wallet, it came through but still didn't confirm after 20 hours. So I tried resetting the blockchain and transactions, and now my wallet is empty! I got the message

com.google.bitcoin.store.BlockStoreException: Corrupted block store: could not find chain head

I searched for this and found advice about deleting the.spvchain file, but I don't appear to have this file!

Edit: Ok, so I just downloaded the newest version of multibit and the bitcoins appeared. All is good! Thanks for the info.


texts: Is there any service/api for deriving HD wallet addresses from a master public key?

texts:
I need this for a tool i'm writing that generates a transaction history report.   think:  accounting, auditing, etc.   The tool does not and should not have access to the private keys.

Ideally, the API would:

not require creating a wallet first.  I only need it to derive keys.
return only addresses that have been used (received funds), up to the gap defined in bip44.

Alternatively, are there any command-line tools that can do this?


texts: I know I had Bitcoins back in the Day, but

texts:
I have all my old computers and have the hard drives, so how do I systematically go back finding which on has my bitcoins?  At the time, I figured it was no big deal, but now finding the correct one, could be worth while.

So my question is, how to I search my hard drives to find the one that contains the bitcoins?   Is there a file I need to search for?


texts: I was downloading bitcoin for the first time and during the last 3 minutes while doing some other work on my computer, something about an interruption flashed and then it looked as if nothing had ever happened and it was not downloading. I went to the file I had saved it in and there was a Bitcoin Core [test net] so I clicked on it and it is now synching. Is this normal? Any advice? I was told to start the download again?


texts: How to send bitcoins without the bitcoin client in PHP

texts: Is there a way to send bitcoins programmatically without the bitcoin client using PHP?


texts: Why was the transaction fee more for a 20 mBTC transaction than for a 25 mBTC transaction?

texts:
I just created a transaction to send 20 mBTC. The transaction fee was more than for a previous 25 mBTC transaction that I sent. Why is that?

I'm using the Bitcoin Wallet App, vers. 5.24 by the Bitcoin Wallet developers.


texts: Why the message is need in verify function

texts:
here is the how bitcoin works under the hood article
http://www.imponderablethings.com/2013/07/how-bitcoin-works-under-hood.html
i did not got this why message is needed when using this verify function ?
1 =? v(message, public key, signature)


texts: Which exchanges allow me to transfer funds from my CurrencyFair account?

texts:
[Update: In July, 2013 CurrencyFair has stopped allowing delivery of funds to any Bitcoin exchanges.]

I can add funds to my CurrencyFair account via a bank transfer from a number of countries.  This will be a convenient method if I can then send those converted funds as a bank wire transfer to a Bitcoin exchange.

TransferWise used to allow me to do the same thing, but then stopped after their banking partners "weren't comfortable with Bitcoin".

Are there any exchanges which allow this?


texts: What is the input and output script of the funding transaction?

texts:
I'm looking for what the state block look like on the blockchain to set a channel on the lightning network.
I found everywhere that the input script is a multisig script (since the two people that set the channel will put there state on the blockchain), but I can't find how they lock the amount until the channel is closed.

So I have two questions :
What is the script of the output script of the state block (the block that starts the channel)?
Where to find such information ?
If you have the scripts of the block that is published on the blockchain after the channel is closed, I would gladly take them also :)

Thank you for your help!


texts: How can bitcoin transactions for the same coin belong in different blocks?

texts:
Isn't each transaction dependent on a hash of the previous transaction?  Wouldn't that mean all of the transactions for a particular coin would have to be grouped in the same block?  As far I can tell this is not true, so by what mechanism are transactions for different coins grouped in the same block.

Everything I've seen on StackExchange about this refers to hashing in blocks, which makes sense to me on the level of blocks, but then I don't understand the level of hashing of transactions since it seems transactions are not organized into blocks by coin.

So I guess a different way to phrase this is how can transactions from unrelated coins be organized into a block?  Because as I previously mentioned, I thought that each transaction was dependent on a hash of a previous transaction.


texts: I can't connect to RPC from python. JSONRPCException: -342

texts:
Tryed to run this code :

from bitcoinrpc.authproxy import AuthServiceProxy, JSONRPCException
import logging
import json

logging.basicConfig()
logging.getLogger("BitcoinRPC").setLevel(logging.DEBUG)

rpc_connection = AuthServiceProxy("http://%s:%s@127.0.0.1:18332"%('user', 'password'))
print(rpc_connection.getinfo())

with my pass and my username but I have this error:

DEBUG:BitcoinRPC:-1-> getinfo []
Traceback (most recent call last):
  File "/home/conio/Scrivania/conioclass/conio/components/provaRPC.py", line 9, in <module>
    print(rpc_connection.getinfo())
  File "/home/conio/Scrivania/conioclass/conio/components/bitcoinrpc/authproxy.py", line 139, in __call__
    response = self._get_response()
  File "/home/conio/Scrivania/conioclass/conio/components/bitcoinrpc/authproxy.py", line 187, in _get_response
    'code': -342, 'message': 'non-JSON HTTP response with \'%i %s\' from server' % (http_response.status, http_response.reason)})
bitcoinrpc.authproxy.JSONRPCException: -342: non-JSON HTTP response with '401 Unauthorized' from server

Can you help me?


texts: How to get addresses from a transaction's vin?

texts:
How can i decode addresses from the following transaction's vin.

Transaction:

https://blockchair.com/bitcoin/transaction/ed8286d06f6df2269e8481b37bbc532c11d80bd2d1b155c920a0742daf3185b2

There are

Example for an address
https://blockchair.com/bitcoin/address/m-3c0cd9cd5bdd9d778d9fe4fe4af1a67e


texts: Can you use non-standard characters for creating a Bitcoin Brain Wallet?

texts:
Can you use non-standard characters to create a bitcoin brain wallet? Ex. Chinese characters, ascii characters using the numberpad with ALT key.

Is there downsides to this?


texts: Receive bitcoin before block downloading is finished

texts:
here's the story:

I've downloaded Bitcoin v0.8.5-beta and bought myself some bitcoins before the block downloading was finished. Now the downloading is still not finished (3 days and counting): 250k and a bit with a rate of 100 an hour or so. I' ve got a bit of an older computer so that's probably not helping.

Question: will I ever see my bitcoins and/or is there another way to transfer it to another wallet? Or is there a way to download the blocks faster?

I'm fearing that the rate of blocks created is higher then the download rate of my computer...


texts: Does cancelling an order in BTC-E carry a fee?

texts:
I want to know when BTC-E charges it's 0.2% fee on a cancelled buy/sell order...

When placed but 0% completed
When placed but partially completed

How much are you billed in each case?


texts:
How do I update offline Electrum wallet after receiving payment with Online seedless wallet?

The guide at: http://electrum.org/tutorials.html#offline-mpk does not say. It only says how to make payments from the offline wallet but not how to receive money to it. I can receive payments to my online seedless wallet, but I don't know how to transfer that to the seeded offline wallet.

Thanks.

P.S. In case some Electrum dev read this there is also an outdated instruction: [Offline PC] Go to Settings -> Import/Export and copy your "Master Public Key" and put it in a text file on your USB-Key. >>> This is now Wallet -> Master Public Key.


texts: Bitcoins not showing up in Bitcoin-Qt wallet

texts: I bought 1 BTC from localbitcoins.com and received my bitcoin in my online wallet with no problems at all, after that I then sent it to my "bitcoin-qt wallet" address located inside the Bitcoin wallet itself under the "receive" tab. My bitcoin transaction seemed to work because the transaction information was on blockchain.info but once I looked at my "bitcoin-qt" wallet there where no bitcoins in my balance? Where have I gone wrong? Where have my bitcoins gone? it also says (out of sync) on the overview page and also "no block source available on the bottom left next to a bar saying "32 weeks behind"


texts: Good documentation on starting bitcoind and bitcoin-cli after building them on Ubuntu Bionic

texts:
I have been following Antonopoulos book but it seems to be outdated.

I am having elementary problems. Which command to run when, after I build bitcoind and bitcoin-cli. How am I to get blockchain to start downloading?

Start with the infamous bitcoin.conf which doesn't exist and nobody knows exactly how it should come into existence.

  :~/.bitcoin$ bitcoind -datadir=/mnt/d/blockchain -txindex=1 -daemon
  Bitcoin server starting

Ok, I assume it is now doing something, like downloading blocks.

But:

~/bitcoin$ bitcoin-cli -datadir=/mnt/d/blockchain -getinfo
{
  "version": 170100,
  "protocolversion": 70015,
  "walletversion": null,
  "balance": null,
  "blocks": 0,
  "timeoffset": 0,
  "connections": 0,
  "proxy": "",
  "difficulty": 1,
  "testnet": false,
  "keypoololdest": null,
  "keypoolsize": null,
  "paytxfee": null,
  "relayfee": 0.00001000,
  "warnings": ""
}

implies that nothing is going on. Nothing is being downloaded.


texts: How do I choose new lightning channels in order to minimize hops when rebalancing?

texts:
Currently my fees are quite high when I try to rebalance and I noticed that I can't rebalance some channels from any of my other channels. I have only six or seven channels and would like to expand to at least 10 for now.
Up until now my strategy for choosing nodes to open channels with was to use https://moneni.com/mcb/nodematch to maximise for the total number of nodes my node can reach with the least hops.


texts: How do mining pools distribute work effectively?

texts:
What does the mining-pool architecture look like? Obviously GPU's can hash data much faster than it can be distributed via the internet, so I assume pools must allocate a range of nonces for miners to work on at any given time?

So if there were 2 miners, would the pool server allocate nonces 1-100,000 to miner 1, 100,101-200,000 to miner 2, then keep allocating the work as each set of nonces are completed? Or do I have it wrong?

I tried digging into the source of Eloipool, but it all seems very cryptic/there is very little (if any?) documentation?


texts:
Why does the Satoshi client not use blocking synchronous communication with peers? I think that is mush simpler than the current asynchronous scheme.

I mean after a node sends out a request, it waits for the response in a blocking manner, with a timeout deadline. After the response has arrived, it starts to send the next request. Doesn't this way have better control of communication context?


texts: How to efficiently find if in-address in transaction is valid and has required amount of data?

texts:
A transaction has in-bitcoin address. Transaction tells to transfer that address (in fraction or whole) to another address. Since the source of truth is block-chain, how does miner know that in-bitcoin address has said amount of data ? And how does miner check it efficiently ?

I have read about Merkel trees. My understanding is that they help to find whether a transaction is present in specific order in a block. But a block chain will have many blocks. So, how is it done efficiently by miners ?

Will not creating a hashmap from bitcoin-address to amount will be easier ?


texts: What permissions should wallet.dat have to be as secure as possible and still work?

texts:
I would like to restrict the permissions on my wallet.dat file but but I don't want to stop the bitcoind daemon from functioning.

What are the bear minimum permissions that need to be on wallet.dat to make it functional, while making it as secure as possible?


texts: How hard is it to transfer money between Bitcoin exchanges?

texts: Say I had a 100$ in a Mt.Gox account and wanted to send it to my TradeHill account, how hard is it to perform a transaction like that without going through a separate bank account? I'm mostly asking in a context of automated trading bots, buying and selling Bitcoins at different exchanges.


texts:
I know that maybe it's a bit early to start asking Wallets to implement Lightning Network connections even if the majority don't support SegregatedWitness yet.

But how about Payment Channels? In theory they have already been out there since long ago, and as far as I understand, they are not affected by transaction malleability if not combined with other channels forming a (lightning) network. So then, is there any wallet out there that already implements them? I only find libraries (such as BitcoinJ) that have support for them, but not wallets.


texts: Why don't the miners just take profit from our coins and make the coin worthless?

texts:
You own a very valuable thing and you want to go to holiday without it, but there is nobody who you trust and who can look after the thing. So you take somebody unknown to guard it. You pay him a fee hoping he doesn't run away with the valuable think. How much would you pay?

I think you should pay for the fee minimum the value of the valuable thing!

But now to bitcoin. Do the story again:
You own a very valuable coin which is guarded by somebody unknown (the miners). You pay him a fee (mining profit) that is much less than the value of the coin (market cap of bitcoin). Why don't the miners hold short positions on the coin, bring value of the coin down with a large majority attack which destroys any trust in the coin and go with benefit from the destruction?

I asked this fundamental question about bitcoin in a stricter way 2 days before in this question and similar in this question and there is also a bounty for an answer, but there is only less interest and no upvotes and no good answers. I think the question is fundamental, and so I tried to do it in an easy analogy now.


texts:
When investing in bitcoins can you lose any more than the total amount of currency with which you invested?

Gentlemen, I see my original question has caused a bit of debate. I have been asked by someone to be more specific as the question seems to be causing some confusion. Let me give an example. If I invest 500 US dollars into buying bitcoins; let's say this is not money loaned, but my own money from my own personal savings account; let's also say that I do not trade or buy anything with these bitcoins. This is purely a financial investment with the hope of gaining a return one day of say, 600 US dollars; is it possible (maybe even likely?) that I could lose not just the 500 dollars invested, but also more than this, say 520, 550 or 600 dollars? You experts, please take account of all possible scenarios, fees and other hidden costs when answering my question. Thanks!


texts: Sending Bitcoin to a wallet but user has not received

texts:
Good Afternoon,

I sent bitcoins to a user's wallet 2 days ago. Below is the transaction id:
9031b7d71ac55d2982b4451d3a0ec9ec1f80575a07afb5fe0d1a29eed5aa7841

And the wallet address:
1DDfbQNfm7UGWM4jp4CxJF631axDCafSD4

However, I was told that the bitcoin had not showed up in his wallet although the transaction has been confirmed.

May I know what may be the issue?


texts: A friend sent me Bitcoin to my blockchain wallet. It shows the amount as part of my balance. However, it says there are 108 confirmations and the number of confirmations keeps going up. Why is this happening? Can I spend this Bitcoin while confirmations are continuing?


texts: How does the U.S. government view Bitcoin? Is it money?

texts: How does the U.S. government view Bitcoin?  Is it a currency, a commodity, or something else?


texts: Is there any way to buy bitcoins online without a fee?

texts:
I'm new to bitcoins, and my experience is from something like E*Trade buying on the NASDAQ, so that's my frame of reference. I paid a small broker fee for every buy or sell, and I trusted the exchange and the software 100%.

But I thought the big advantage of bitcoin was no middle man. Hence I assumed no fees.

But perhaps contrary to that first assumption, in my second assumption I thought there would be this big trusted website where you go and buy / sell anonymously without having to trust the other party. You would just need to trust the exchange itself.

Can I buy bitcoins anywhere without a fee?

Can I buy bitcoins anywhere with 0 risk of getting ripped off, as in a flea market?

Can I get both positive things in one place (ideal)?

Thanks.

EDIT

Coinbase Pro allows me to do limit buys for free. The trick there is to set the limit price to the current price and keep changing the price if necessary to get the desired quantity purchased.

Coinbase had been charging me 1% on large buys. So for small buys ok; large buys, it adds up!

CEX.IO on the other hand, gave me large limits and they charge a flat fee of $10. So for a buy of $3000 this is only .33 percent; much better!

Also, something I need to watch out for is the buy price. The exchanges mess with that to make extra margin I think. So I need to shop for best price before committing to buy. Compare the total price including fee based on buy price.


texts: Difference between account balance and the sum unspent transaction outputs

texts:
I have account in bitcoin-core (for example it's "maks") and there I have 0.00010884 BTC.

getbalance "maks"
0.00010884

But when I get UTXO:

listunspent 1 999999 [...array of addresses belongs to "maks" account...]

and sum all amounts up I get 0.00009824 BTC and I don't understand WHY??
I thought account balance is sum all unspent transactions outputs. Please help me!
Or maybe it's don't need me... I want to create raw transactions and for this I need unspent transactions. How I can get these transactions?


texts: How Long Does Miner Wait To Receive Commission From Transaction Fee?

texts: I cannot find the answer so please cite a source if you have one: How long does it take when a miner successfully mines a block to receive the commissions from the transactions included in that block? I ask because it's my understanding that the Block Reward isn't offered until 100 blocks have been added on top of the mined block. I think I read that the Transaction Commissions aren't awarded until 6 more blocks are added, but now I can't confirm that. It stands to reason that there would be some sort of lag before commission are paid by the network in case the mined blocked ends up orphaned or stale. So what is the waiting period?


texts: How to recover bitcoin from a site that is no longer operating?

texts:
In 2013 I had 1.5 but coins on bitinstant. The bitcoin lost money and it was at 73$. Since it was hard to deal with I let it go. I don’t even care to get it out for less than 150$

But now it’s skyrocketed.
The site is shut down though.
Is there anything I can do to find it?


texts: Why not multiply "six confirmations" and divide Time-Between-Blocks and Reward by the same factor?

texts:
It seems that choosing a good factor to use to expand Bitcoin's capacity is a good idea.  The software would divide some of its calculated values by this factor, such as the target time between blocks during difficulty calculation, the number of blocks between difficulty adjustments, and the subsidy.  To achieve the security of "one hour's worth of hashing power," the recommendation for confirmations would be multiplied by this factor.  It seems that using a factor of two from time to time (whenever the community finds it valuable) would be appropriate.

Let's suppose we choose a factor N. This will allow the blockchain itself to grow N times as fast, providing N times the transaction fees to miners, multiplying the number of rewards by N (but dividing the reward itself by N), dividing the average wait for a confirmation by N, and multiplying the rate at which transactions are confirmed by N.  This also reduces the variance of mining revenue.

This allows time (instead of network bandwidth and computer memory) to be used to expand the carrying capacity of the bitcoin ecosystem.  Should such a proposal be written into a BIP?

The objections to this idea so far have been answered in the comments.  If anyone feels that there is an objection adequate enough to drop the idea, please post an answer.  If anyone wants to create a BIP, please let me know so I don't have to do it myself.  I don't mind doing it myself, but I'll probably be slow.


texts: Extract private keys from Bitcoin Wallet

texts:
I have encrypted my bitcoin wallet. I know the passphrase, that's not the issue.

I want to transfer my bitcoins to blockchain.info but it's asking me for the private key. I cannot find it nor can I find how to find it. I have searched around on google; a few sites say that pywallet will extract the private key, but I have used this and all I get is the address I have created.

Where is my private key(s)?


texts:
BIP47 is a new secret-sharing protocol which succeeds BIP64 (stealth addresses).

The test vectors are here.

I am stuck on part 2.iv. We multiply S0 = B0 * a0 (024ce8e3b04ea205ff49f529950616c3db615b1e37753858cc60c1ce64d17e2ad8 *  8d6a8ecd8ee5e0042ad0cb56e3a971c760b5145c3917a8e7beaf0ed92d7a520c = 03f5bb84706ee366052471e6139e6a9a969d586e5fe6471a9b96c3d8caefe86fef).

From that we are looking for:

s = HMAC-SHA512(x, o)
"x" is the x value of the secret point
"o" is the outpoint being spent by the first pubkey-exposing input of the transaction.

What does HMAC-SHA512(x, o) mean, first of all? What is o specifically? And how does this factor in with the test vector values?


texts: How important is the hash power in solving a block?

texts:
What is the role of hash power in solving a black, I have read at numerous place it's more like a lottery to successfully form a block in bitcoin and any such crypto blockchain currencies.

Is it importance of hash power or luck that plays the role? If it's all about hash power then why is so, that people with huge hashes at time fail to achieve blocks but little ones get them? How much is real computation power involved along side fortune factor?


texts:
I can't get the node-bitcoin rpc module running correctly in my express app... Either I get a connection refused error or I get a invalid params -32602

Here's a little code snipped from my app.js file.  Can somebody help me out on what I'm doing wrong here.  FYI, I do have port 8332 and 8333 open on nginx

/******* THIS GIVES ME INVALID PARAMS from -32602 ******/
var net = require('net');
var server = net.createServer(function(c) { //'connection' listener
console.log('server connected');
});
server.listen(8332, function() { //'listening' listener
console.log('server bound');
});

var bitcoinClient = new bitcoin.Client({
host: 'localhost',
port: 8332,
user: 'username',
pass: 'password'
});

bitcoinClient.getInfo(function(e, info){
if(e){ return console.log(e);}
});
/****************************************************************/

/******* THIS GIVES ME CONNECTION REFUSED ******/

var bitcoinClient = new bitcoin.Client({
host: 'localhost',
port: 8332,
user: 'username',
pass: 'password'
});

bitcoinClient.getInfo(function(e, info){
if(e){ return console.log(e);}
});
/****


texts: Error validating a transaction with blockcypher

texts:
I've created a testnet transaction using blockcypher API (https://api.blockcypher.com/v1/btc/test3/txs/new) and then signed the transaction using the signer (go lang). And then sent signed transaction to blockcypher (https://api.blockcypher.com/v1/btc/test3/txs/send)
But it's returning error:
Error validating generated transaction: Error running script for input 0 referencing e41a5ceca53f2cd6076f3a100137d6182d0bd567d91e508f4171712b9c67f429 at 0: Script was NOT verified successfully.

The response I'm receiving:
{
  "errors": [
    {
      "error": "Error validating generated transaction: Error running script for input 0 referencing e41a5ceca53f2cd6076f3a100137d6182d0bd567d91e508f4171712b9c67f429 at 0: Script was NOT verified successfully."
    }
  ],
  "tx": {
    "block_height": -1,
    "block_index": -1,
    "hash": "c514900d8ed184c37bd795c30f24d56508c40ca5f65c2bf8d724162fd8976353",
    "addresses": [
      "tb1qy0jm6vmy2vmndpzzj34z6h6xnelta98d0ukf6s",
      "tb1qwchaysp9wfukq54yee8uye20f2c5zkpl97elvx"
    ],
    "total": 3996400,
    "fees": 3600,
    "size": 222,
    "vsize": 141,
    "preference": "low",
    "relayed_by": "2a01:4f8:192:6027::2",
    "received": "2021-05-01T09:34:02.926591638Z",
    "ver": 1,
    "double_spend": false,
    "vin_sz": 1,
    "vout_sz": 2,
    "confirmations": 0,
    "inputs": [
      {
        "prev_hash": "e41a5ceca53f2cd6076f3a100137d6182d0bd567d91e508f4171712b9c67f429",
        "output_index": 0,
        "output_value": 4000000,
        "sequence": 4294967295,
        "addresses": [
          "tb1qwchaysp9wfukq54yee8uye20f2c5zkpl97elvx"
        ],
        "script_type": "pay-to-witness-pubkey-hash",
        "age": 1973087,
        "witness": [
          "3045022100a4a53cc0eaae807e5c3500af2132a8e575823fc0ff7ceb92de94b739920810ba0220339aa4128967654977b6afb8be9a8897c5e822e2cb5659fe987c106bec44101e",
          "03f2cfd459014d4f19f36e28dcae329ca4f6b263d4d7c13ca7317a75b1a130f0f6"
        ]
      }
    ],
    "outputs": [
      {
        "value": 2000000,
        "script": "001423e5bd33645337368442946a2d5f469e7ebe94ed",
        "addresses": [
          "tb1qy0jm6vmy2vmndpzzj34z6h6xnelta98d0ukf6s"
        ],
        "script_type": "pay-to-witness-pubkey-hash"
      },
      {
        "value": 1996400,
        "script": "0014762fd2402572796052a4ce4fc2654f4ab141583f",
        "addresses": [
          "tb1qwchaysp9wfukq54yee8uye20f2c5zkpl97elvx"
        ],
        "script_type": "pay-to-witness-pubkey-hash"
      }
    ]
  },
  "tosign": [
    ""
  ]
}

Any help would be greatly appreciated. Thank you all.


texts: Bitcoin 0.18: how to send bitcoin from one address to another using Bitcoind?

texts:
To transfer bitcoin from one account to another address, we have used sendfrom method and which got deprecated in the latest version Bitcoin 0.18.0

Bitcoin sendfrom method

On reading the document of Bitcoin 0.18.0, it is suggested to use sendtoaddress method.

sendtoaddress method has two required parameter

"address" - address to which we want to sent BTC
"amount" - amount in whole number

Unlike sendfrom method, there is no parameter where we can pass the parameter with account or address from which we want to send BTC.

Please let me know how can I define the account or address from which I need to send Bitcoins or is there any other method available.

I am using bitcoind to make RPC calls.


texts: Can we calculate unspent of addresses which are generated from other node server if we are having private/public key of those addresses?


texts: Techniques or proposais to require transactions to be included in a block?

texts:
As it stands now, a miner (or mining pool) can discriminate any transaction for any reason if they are running a custom version of code.

Suppose an evil and powerful mining pool decided to hash blocks, but not include any transactions even if a fee was included.  This would slow down the rate a block would be included in the chain.. effectively causing a DOS against certain transactions.

This is intended behavior to encourage transactions to include fees (or soon will be the behavior).  But suppose a pool operator (or powerful mining consortium) decide that they want to kill off Bitcoin and not include any transactions ... at all.

Question

What technical solutions are there to require blocks to have transactions?

Challenge

We don't want the attacker to only include transactions the evil mining pool themselves create, but also transactions that others create as well.
I don't want to encourage too many low-fee transactions in this model, thus de-incentivising mining activity

Is there any solution that addresses these goals in a fair and balanced way?


texts: If i pay 0.001 to cloud mining site such az minezone.io or bitbase.club or 99quick.cloud, they give my balance or no


texts: What happens if a country blocked external Bitcoin traffic?

texts:
Say a country decides to completely sever itself from the outside world, like so. Assume no leaks. As I understand, once the local miners process all the international transactions in everyone's' mempools, they'll be left with only local transactions, blocks, nodes, and miners. A (long) while later the difficulty adjusts downward, and you now have a local, codeless, lower-POW "fork" of BTC, even though it's the same code-wise. Travellers can go there and spend their pre-fork balances there again, either sending it to another address they own, or send to locals, though it's obviously severed from whatever transactions they performed outside this country.

Assuming they keep up-to-date with the codebase only, and they do this for a long time, say a year and more, what happens once connectivity is restored? Is their local chain just completely wiped out due to lower POW? Would local nodes be forced to go back to the time of the fork and download international blocks? All those valid transactions at the time, gone? And roles reversed, what if this country amassed enough mining power to have more POW?

And as a bonus question, how would Layer 2 solutions, assuming they were the only traffic that could cross the border the whole time, affect this scenario? Could you load funds onto the Lightning network from both networks, and effectively double your balance by withdrawing them on the outside network?


texts: Why do people go looking for old hardware that has a wallet?

texts:
Don't you just need the recovery phrase to get your bitcoins back if your computer is lost or damaged?

I don't understand these stories of people trying to find old computers with wallets on them at the dump.


texts: Using dumpprivkey to make a paper backup

texts:
I'm just getting started with bitcoin and haven't acquired any significant amount yet, but want to feel relatively secure before I do. And at the moment, my fear of losing bitcoins or a device on which I store bitcoins is slightly greater than my fear of having them stolen so I'm investigating how to make a paper backup. I have looked around and what I have seen seems more complicated than necessary. I am wondering if I could simply:

Start up my bitcoin 0.7.1-beta client
Transfer all my bitcoins to some address in the client
Open the debug window console
Enter walletpassphrase <my passphrase> 60
Enter dumpprivkey <my address with all the bitcoins>
Print the private key that is displayed

Then if I ever need to recover it, I could import that private key into any other bitcoin client. If it's the same bitcoin client newly installed, I could enter importprivkey <my key>.

My one concern about this is that I have somewhere read that some bitcoin wallets "un-steal themselves" and I am worried and wondering if that means that coins may be automatically transferred to another address at some point, at which time my paper backup would become useless.

How wise is this plan? Is there another way I can or should generate a private key and address to which I can send bitcoins without actually having the private key stored on my system if I have a concern about the security of  the system?


texts: Is BitCoin Mining Basically a Game? Do the Solved Math Equations do Anything?

texts: So I've been trying to learn about bitcoin, I'm a kid. It is really confusing. Is BitCoin basically a game since you solve math equations for money? And also, do the math equations do anything or are they just random and because you solve them, you get a reward for your intelligence?


texts: Can anyone delineate a phrase in the Satosh's white paper?: limiting the minimum practical transaction size

texts:
Can anyone explain what the phrase below, from the Satoshi Nakamoto white paper, means?

Introduction

The cost of mediation increases transaction costs, limiting the minimum practical transaction size and cutting off the possibility for small casual transactions

Can anyone tell me what the writer tried to say?


texts:
Let's say I implemented AuxPOW to all of the alt coin wallet.
Would it let me merge mine them with Bitcoin or the developer would have to implement them?


texts:
Most wallets these days generate a set number of addresses when you create the wallet. For example, Electrum creates 30. But what if you need more? I know from talking to a LOT of people that there is safety in having each transaction to your wallet via a different address. So 30 addresses isn't going to last very long. I've seen people talk about generating new keys from which to generate new addresses. However, that is as far as my understanding goes. So, let me ask it this way.
I currently use Electrum as my BTC wallet. I've got a new wallet just generated in that program with all 30 addresses. That's how I am used to doing things. I've also recently installed bitcoind on my server where I expect/hope to be receiving BTC to. I got bitcoind so that I coulduse it to verify when transations have been verified. But I do not understand how to link bitcoind and the wallet I created in Electrum. Nor do I understand how to add additional keys/addresses to that wallet.
I've seen people talk about BTCPay server. But that seems to be more a storefront. I don't need all that. I just need a way to display a randomly created address to each visitor, and to be able to query my Electrum wallet (or use bitcoind) to find out how much is in the wallet at the present moment, preferably in both confirmed and unconfirmed funds (i.e. 0.162567 BTC confirmed, 0.0125 unconfirmed).
Any easy way to do that is appreciated. I'm writing this site in PHP, so I can either execute an external program (like bitcoind or Electrum's CLI interface) or I could make API calls in PHP directly if there's a good set of PHP libraries around.


texts:
I'm wondering if its possible to add imported addresses into the bitcoin conf file.
So, rather than calling the cli with importaddress, I would add the address to the conf file, with say, importaddress=1123345678A
Is this supported in the conf file?


texts: What is the most expensive Bitcoin purchase ever made?

texts:
Relying only on publicly disclosed data, what is the most expensive Bitcoin purchase that has ever occurred?

"Expensive" can be determined either by:

Highest purchase price in Bitcoins
Highest fiat value equivalent at the time


texts: Is one blockchain of one exchange place the same blockchain used in other exchange places?

texts:
Sorry if the title is confusing, here is what I mean.
I recently threw some fiats in Kraken and invested in Bitcoin, the first interrogation I had was "Can I see my transaction publicly on the internet if I could find the right block used for it?".
But on a large scale this interrogation translates to "Is each exchange platform implementing their own clone of the Bitcoin specs or is there a general blockchain that rules the entire decentralised financial system?"


texts: Order books, matching exact price or closest price?

texts:
After reading this How do buy and sell orders work?.

This says that closest price, so if someone is selling at 999, and someone offers a bid of 1000, that the 999 will get sold since its the two orders that match closest.

I trade on btce, my understanding was that orders have to match exactly in price. And I take it its considered a sell or buy depending on who goes first.


texts: Automatic savings account using 2 wallets?

texts:
Sorry if this has already been asked; Stack Exchange didn't have this exact question in the "related" field.

Let's say I have two bitcoin wallets. Somebody sends wallet 1 a transaction of 0.5 BTC.

What I am wondering is if I can take that transaction and create a new one, where I'm sending 0.4 BTC to that same address in wallet 1 with the original 0.5 BTC (the one listed in the "receive" data in the UTXO), and sending the 0.1 BTC change to an address in wallet 2.

I would think this is possible since the address in wallet 2 referenced as part of the second transaction would then have the funds available once the transaction confirms in the block chain.

I just don't know enough about Bitcoin's code to know for sure if this won't cause some sort of hiccup, as my general conception of "transaction change" is that an address local to the wallet, in this case wallet 1, is generated for capturing the change from the transaction to avoid overspending in transaction fees.

Using a separate wallet's address as the change may well break something in the code that accounts for the total balance of the first wallet.

This is why I need an expert to help me out here. Too many unknown outcomes for me!


texts: Hash Time Locked Contract (HTLC) using bitcoin-qt

texts:
Is it possible to manually create a Hash Time Locked Contract using the bitcoin-qt command line?

I have dabbled with manually creating createrawtransaction / sendrawtransaction using the bitcoin-qt clients command line, and wanted to know how to manually create a Hash Time Locked Contract.

When  I say "manually", I mean, really getting your hands dirty, like using notepad to construct the contract/script, putting the values into bitcoin-cli, to convert it into a hash, ready for it to be sent using sendrawtransaction.


texts: What is the difference between the mnemonic and the private key?

texts:
My thinking so far:

If I have a private number, then I can use that as the private key.

If I have a mnemonic, I can match up each word to a number in the wordlist to get the seed, which is the private key.

Is this correct?


texts:
How can I use Bitcoin cash from the command line? In my understanding, even standard bitcoind and bitcoin-cli should work fine with it because the only blockchain was changed.

But may be there are any special tools/flags? Can you give some dead simple example, e.g. adding the new address to account and checking it's balance? With Bitcoin and bitcoind it can be done with 3 lines of code:

$ bitcoind -daemon
Bitcoin server starting
$ bitcoin-cli getnewaddress pavlovdog
1PB8NHbSG3CgvpzSMrvdeeAKaojZBXrwb # I've sent to this address 0.0001 BTC
$ bitcoin-cli getbalance pavlovdog
0.00010000

Thanks in advance!


texts: Valid fork in regtest - Change blockchain via RPC?

texts:
I've created a regtest network consisting of 2 nodes - node0 & node1.
I'd like to have a fork on the common blockchain and seemingly achieved it by doing so:

nodes start
node0 adds node1 via addnode
node0 generates 1 block with hash 4dac...
node1 generates 1 block with hash 5d8b...
node0 invalidates node0's block with hash 5d8b... via invalidate <hash>
node1 stops
node0 generates 1 block with hash 64f2...
node1 restarts
node1 generates 1 block with hash 5sfg...
node0: getchaintips returns an array with invalidated block's hash 5d8b... with status

Now my questions:
a) How can I achieve a "valid-fork" status in the output of getchaintips for the previously invalidated fork? [SOLVED]

b) Is it possible for a node to "conciously"/via RPC give up its own chain and switch to the competing chain?


texts: I sent money from my BTC (Blockchain) to BCC (coinbase) by accident. Any help to recover the funds? Both accounts are owned by me

texts:
I sent money from my BTC (Blockchain) to BCC (coinbase) by accident. Any help to recover the funds?

I need help as I know transactions cannot be refunded but I have read a few forums where people have recovered it.


texts: Is it safe to show the QR code to his friends?

texts: I was opening my Jaxx wallet this morning and some of my friend made a pun saying they would take a phoyo of tmy QR code to buy some tickets with it. I was therefore wondering if it was safe to show the QR code ? What does it stands for ? Here is an example from the ETH forum.


texts: How do I get started debugging Bitcoin Core functional tests?

texts: I would like to get started with debugging Bitcoin Core code. I have heard debugging Bitcoin Core functional tests is a good place to start as they are in Python rather than C++ and they are easier to understand. Any recommendations or good resources to help me do this?


texts: Can a blockchain be created that forgets transactions whose outputs have been spent?

texts:
Is it possible for a blockchain based currency to say, after all outputs have been spent from a transaction to "delete" it from the blockchain, or at least require the nodes not to download it, what methods are there for achieving such a goal ?

The problem I see with pruning is that you still have to first download the entire blockchain from a node and then prune it. I am looking for a method which doesn't require the whole chain ever to be downloaded.


texts: Is the idea of fraud proofs possible in reality?

texts:
I once read this on Twitter, which is said by Luke Dashjr, a Core dev:

  The original design was to have full nodes create proofs of invalid
  blocks, to alert SPV nodes to them. SPV nodes would then verify these
  proofs and reject the invalid blocks. But it turns out, it isn't
  possible to prove a block is invalid.

So I wonder whether the idea of fraud proofs is actually possible? If not, why?


texts: I sent bitcoin from my blockchain to my paxful and it says pending in my paxful history 0/3 confirm. Please what happened. And the bitcoin has left my blockchain wallet and it only showing unconfirmed in paxful history


texts: How do I compile Bitcoin Core to be more portable?

texts:
Background: I compile bitcoind on one system but run it on another. When I compiled bitcoind 0.19.1 some time back using the following method, I was able to run bitcoind and bitcoin-cli on the target system without issue

./autogen.sh
./configure --disable-wallet --disable-tests --disable-bench --disable-gui --enable-util-tx=no --prefix=$HOME/bitcoind/x64 --exec-prefix=$HOME/bitcoind/x64
make && make install

Today I compiled v0.20.0 using the same method. If I run ./bitcoind -version on the system I compiled the binary it runs fine, but if I take the binary to my target system I get the following error:

./bitcoind: error while loading shared libraries: libboost_filesystem.so.1.67.0: cannot open shared object file: No such file or directory

The binary seemed to be portable last time, and the pre-compiled binary I download from the Bitcoin Core team runs fine.

Note that on the target system libboost-filesystem-dev and libboost-filesystem1.67-dev are not installed, this is likely the source of my error. That said, running the pre-compiled binary from the Core team runs, so why doesn't mine?

Can someone help me understand if I did something wrong or if I need to add ./configure flags to make the binary more portable? Specifically what I likely did differently than the core developers that made my binary fail where theirs worked?

EDIT 1: Running ./configure --enable-static or ./configure LDFLAGS=-static does not result in a portable binary either.

Also note that installing libboost-filesystem library with apt does fix the error.


texts: Is the Bisq API finally "live" now or what?

texts:
For many years now, I've been waiting for Bisq to implement its damn API so I can begin trading (between crypto currencies, since automation is impossible with fiat).
Today, I again did a "round" to check if it has happened, and... I'm not sure? There are numerous old posts about the different APIs, and recent mentions of it, and there's this cryptic "documentation": https://mrosseel.github.io/bisq-api-examples/
But is it actually "live"? Can I start automatically trading with it today? Or is this still in some kind of "test-only" mode?
I would have asked them directly if it weren't for the fact that every single channel they provide to communicate with them refuses registration or requires weird software to be installed.

More information: https://helloreverb.com

It's probably not a good sign that this shows some kind of generic "under construction" message...
I've browsed their official website for a long time without finding any mention of the API, so I assume that it's not live?


texts: Endianess of txids when calculating Merkle Root from getblocktemplate

texts:
I am trying to solve a merkle root from a previously mined block.
Specifically this block...
https://www.blockchain.com/en/btc/block/000000000003ba27aa200b1cecaad478d2b00432346c3f1f3986da1afd33e506
TXHash1: 8c14f0db3df150123e6f3dbbf30f8b955a8249b62ac1d1ff16284aefa3d06d87
TXHash2: fff2525b8931402dd09222c50775608f75787bd2b87e56995a7bdd30f79702c4
TXHash3: 6359f0868171b1d194cbee1af2f16ea598ae8fad666d9b012c8ed2b79a236ec4
TXHash4: e9a66845e05d5abc0ad04ec80f774a7e585c6e8db975962d069a522137b80c1d
https://medium.com/@stolman.b/1-4-hashing-transactions-txids-to-find-the-merkle-root-3aa5255f8de8
The blogpost above goes through the process of converting the transaction IDs to little endian.
To solve the merkle root.
Question: When mining new blocks using getblocktemplate
According to the bitcoin developer documentation, transaction hashes are given in little endian already.
transactions
"hash" : "xxxx",             (string) hash encoded in little-endian hexadecimal (including witness data)

So... do I skip that step ?


texts: Is the block timestamp reliable enough to timestamp the hash of a document?

texts:
In using the blockchain to timestamp the hash of a document, so to prove that it existed before a certain time.

Is it reliable? Do you think it can stand on court? (IANAL and probably you neither) What is the worst that can happen? For example, What if many nodes change their internal clocks to hack the median of the time.


texts: I'm trying to implement a bitcoin full node while learning a new programming language, but I can't find the full set of public API that the full node has to expose. I assume the standard will be bitcoin core, but then again the closest I can get is the https://bitcoin.org/en/developer-reference . Where should I start from?


texts:
I have repeated this process a few times, always with the same error.

In one terminal,

./bitcoind -testnet

in another

./bitcoind -testnet getnewaddress

mgj4Y8AvckxborhQzqFAhppcGVGFExqJvB

./bitcoind -testnet dumpwallet /path/to/testnet3/wallet.dat

error: {"code":-1,"message":"CDB() : can't open database file wallet.dat, error 22"}

./bitcoind -testnet stop

Bitcoin server stopping

In the original terminal,

libc++abi.dylib: terminate called throwing an exception
Abort trap: 6

Then I type

./bitcoind -testnet

Error: wallet.dat corrupt, salvage failed

Anybody have an idea what is going on? I updated my bitcoin to the latest on github. I also searched for the error 22 but didn't find anything. I'm guessing CDB means corrupted database. I also looked in debug.log, but I didn't see anything weird.

I know it is the dumpwallet command that is breaking it, because when I omit it from this process, nothing breaks.

The same things happens on the mainnet, altho I have not tested it as much.

Am I using the dumpwallet command incorrectly?


texts:
I was trying to see how the trading volume and market cap of Bitcoin are compared to each other. I quickly found https://coinmarketcap.com/ and similar sites which tell the same story:
Bitcoin has a market cap in the order of magnitude of 18.5M btc (currently about 500B USD) and a trading volume around  1.6M btc (50B USD).
I guess that the market cap (measured in btc) is pretty much spot on, as I am not aware of coins that stay invisible to the chain.
However, I am still curious to get some feeling for the actual volume of Bitcoin that changes hands. I suppose one could categorize this in 3 buckets:

Transactions that hit the chain (presumably the volume of this is 1.6B)
Coins transferred via well known places, perhaps exchanges
Coins transferred via other methods, perhaps giving someone your wallet

Now my question:
#What is the estimated trading volume of Bitcoin?
My first thoughts:

If my above logic is correct, we could add up exchange volumes to the chain volumes
Perhaps there is some insight in the proportion of the three categories, so we might even estimate the third bucket and thus the total

I am aware of this question, and believe it confirms my definition but does not answer the question about the actual volume: Bitcoin trade volume and trade transactions

Bonus:
I imagine some of the transactions are simply from one entity to itself. I do not believe this can be identified, but if it is known to represent a certain estimated volume that would be interesting as well.


texts: GUIMiner won't start mining on Slush's pool

texts:
I started co-mining on Slush's pool successfully for about 48 hours, but from there on I haven't been able to connect to it again. It logs in the console this, no matter if I'm using a valid worker and password or not:

2013-05-26 12:55:19: Listener for "Default" started
2013-05-26 12:55:20: Listener for "Default": api2.bitcoin.cz:8332 26/05/2013 12:55:20, checking for stratum...
2013-05-26 12:55:20: Listener for "Default": api2.bitcoin.cz:8332 26/05/2013 12:55:20, started OpenCL miner on platform 0, device 0 (Turks)
2013-05-26 12:55:20: Listener for "Default": api2.bitcoin.cz:8332 26/05/2013 12:55:20, no response to getwork, using as stratum
2013-05-26 12:55:20: Listener for "Default": api2.bitcoin.cz:8332 26/05/2013 12:55:20,  No JSON object could be decoded
2013-05-26 12:55:30: Listener for "Default": api2.bitcoin.cz:8332 26/05/2013 12:55:30, Failed to subscribe
2013-05-26 12:55:32: Listener for "Default": api2.bitcoin.cz:8332 26/05/2013 12:55:32, IO errors - 1, tolerance 2
2013-05-26 12:55:33: Listener for "Default" shutting down

Of course, I've checked my connection, and I've started GUIMiner with administrator privileges. I'm using Windows 7.


texts: Transaction still listed as 'pending' after 12 hours

texts:
I'm using Electrum 2.5.4 on Tails 2.2.1

Sent the following transaction over 12 hours ago with 0.0005 BTC/kB transaction fee.

There's a warning message saying the transaction has a none standard input - which after googling doesn't seem to have a concensus on what to do about this

What gives? Any help much appreciated

https://blockchain.info/tx/22e6190880cb2433fb99f27e7daf1a763c5e86d64fadb40b708be8295283a052


texts: Can bitcoins be exchanged by mailed check?

texts: I am wondering as I'm (obviously) a newbie to Bitcoins.  I'm not necessarily looking to do so, simply wondering how transactions can be made/what options there are for exchanges


texts: How did these 3 tx make it into a block in the main chain?

texts:
http://blockexplorer.com/block/000000000000051b42fd09195c75da7a084df7593f47ad18139cdc9cd83a112e

The last three tx have a inputs with script_sig "1".  This is invalid right?

According to protocol rules https://en.bitcoin.it/wiki/Protocol_rules#.22block.22_messages it seems like the block (even if mined) should have been rejected by peers.

  16.1.4: "Verify crypto signatures for each input; reject if any are bad"

What am I missing?  Thanks!


texts: Is it possible to use bitcoind as a private blockchain?

texts: For development or test purpose, is it possible to setup a bitcoind as a private bitcoin blockchain?


texts:
I am trying to run Vitalik Buterin's python bitcoin wrapper.

I installed it from PyPi (pip install pybitcointools ).

When I try to run:

import bitcoin

I get the following error:

  ImportError                               Traceback (most recent call
  last)  in ()
  ----> 1 import bitcoin

  ImportError: No module named 'bitcoin'

I will appreciate any pointers on this


texts: What is the most reputable Bitcoin payment processor that has privacy friendly terms and conditions? BitPay and Coinbase are known to have used chain analysis to spy on customers. What are the alternatives for reputable merchants who do not approve of this type of privacy violation applied to their customers?


texts: Are bit coins taxable? Another words if you accept bit coins when you sell an item do you pay taxes on the proceeds if your accepting bit coins?


texts: Unconfirmed transaction for 2 days despite network fees, rescans and redownload

texts:
I made a transaction 2 days ago, (using BitcoinQT 0.8.1-beta on MacOS X) that didn't propagate. I can't find the transaction on blockexplorer or blockchain.info (or anywhere else for that matter) yet. The transaction just sits there in the client, unconfirmed and gobbled up my Bitcoins. The transfer required me to pay a tx fee that I gladly paid.

Status: 0/unconfirmed
Date: 06.04.13 22:01
To: Satoshi Dice 78% 1dicec9k7KpmQaA8Uc8aCCxfWnwEWzpXE
Debit: -0.40 BTC
Transaction fee: -0.0005 BTC
Net amount: -0.4005 BTC
Transaction ID: 10cfa399f5c0a3c6a36e9678ae7c87af95f38899cfe21c7bd76caebd11a2919b

What I did thus far

I let the client sit on the network for a couple of hours, hoping for it to re-send the transaction.
I found this debug thread that suggested to use -rescan, which I did to no avail.
Then I backed up and deleted all data except the wallet to redownload the blockchain - which also failed to change anything.
I used the gui console to do a lookup and resend of the transaction using getrawtransaction / sendrawtransaction that resulted in the error below

Error:

getrawtransaction 10cfa399f5c0a3c6a36e9678ae7c87af95f38899cfe21c7bd76caebd11a2919b 1
No information available about transaction (code -5)

sendrawtransaction 10cfa399f5c0a3c6a36e9678ae7c87af95f38899cfe21c7bd76caebd11a2919b
TX decode failed (code -22)

Now I am wondering what went wrong and what steps to take next.

I am aware that similar questions have been posted before, but I think this instance is different because I feel I already exhausted the debug instructions provided in the debug thread. I apologize if I missed anything.


texts:
I am working on a private chain using regtest mode. I have a strange behaviour if i restart the bitcoind process the balance becomes 0.?

i generate 101 new block to get the reward 50BTC. I repeat this operation to be sure but always i get the same result the balance is 0.

before
C:\WINDOWS\system32>bitcoin-cli -regtest getbalance
8800.00000000
after
C:\WINDOWS\system32>bitcoin-cli -regtest getbalance
0.00000000

update : the problem was the use of CTRL+C to stop the bitcoind deamon


texts: Using NBitcoin or C# to derive Litecoin and Ethereum Addresses from Master HD Key

texts:
I am using NBitcoin, C# and the Bip44 standard to create an hdroot to derive child keys from. I then create keys that I want to use for Litecoin and Ethereum addresses by setting the proper 'coin_type' in my derive statement:

var ltcAddress = hdroot.Derive(new KeyPath("m/44'/2'/0'/0/0"));
var ethAddress = hdroot.Derive(new KeyPath("m/44'/60'/0'/0/0"));

Obviously these are Bitcoin addresses by default. How can I now convert them to the proper Litecoin and Ethereum counterparts?


texts: Which file is the source codes of regtest net located?

texts: I try to compare the source codes between main net and regtest net of bitcoin. I am not sure where the source codes of regtest located. Would someone help me, please?


texts: Is it illegal to trade Bitcoin OTC in the United States

texts:
I am considering selling Bitcoin OTC.  As far as the legalities go, is it legal to anonymously trade Bitcoin for cash without taking KYC information and registering with FinCEN?  I know all the "big boys" like Gox require information but I am vehemently against that and I'm too small to pay all these registration fees as well as keep up on the behemoth of AML laws.  This is more for some extra side cash and to help people get BTC easily.  How big of a boy do you have to be?  I however do not want to do anything illegal.  I do not want feds showing up at my door.  What limits must I conform to in order to comply with the law?

I plan on doing local cash and bank deposits.  Will a bank flag you for having $1,000/mo being deposited into your account at random locations?  $10,000?  $20,000?  What are the limits before things get frozen and\or become illegal?  Before I have to become a legitimate MSB

I want to make it clear that I do not believe in tax evasion.  I plan on accurately reporting all profit made.

I do live in the US.  I will be selling in the US.

I noticed this similar question (Legal issues / banking issues selling Bitcoins to people OTC?) and it mentions a limit of $1,000 per day per person.  Does that mean I as a seller can not do more than $1,000 per day (since I am a person), or each individual person I deal wtih can't do over $1,000 per day?


texts: Invalid p2sh transaction accepted by the network

texts:
I have try to build a 2 of 2 p2sh transaction from scratch using the book "programming bitcoin" by Jimmy Song, we are not directly guided to make one of those so I had to modify some of the function we had to build in the book but I guess it must be working.
Here is my tx on testnet: https://www.blockchain.com/btc-testnet/tx/7eba40f4c00e3da529309011c6fd8066c97fd24adca60b0d024976c360bcdd8b
And here is my code: https://pastebin.com/1mCv73i2
using the functions of the book: https://github.com/jimmysong/programmingbitcoin
My question are:

Why did the transaction was accepted by the network despite not working as intended
Why did my input did not go to the desired p2sh address "2N7e6ZAGXoepdVYu2Y8ho7fTf6oxE3j9UwS"
It is on the testnet but if it was not can I retrieve my satoshis on this tx ?

edit: I found my error about my redeemscript and updated my code, but now I have a "Code: -25, Error: bad-txns-inputs-missingorspent" error when I want to broadcast it
here is my raw transaction, and I have updated the pastebin for the code:
https://pastebin.com/8sQBpnVY


texts: I traded XRP for BTC. How do I withdraw my bitcoins from ripple.com? I guess I need to withdraw to bitstamp.net somehow?


texts: How is address recognized between wallets

texts:
Lets assume I create a wallet in Jaxx and Bittrex for ETH token which in turn creates public & private key pair. I am able to transfer coins between different wallets.

How is the address generated by Jaxx recognized by Bittrex wallet ? Is it because the underlying process of (PGP) generation of public key is same ?

How different is this process from PGP ?


texts: When is a Bitcoin Adress considered even and when odd?

texts: When is a Bitcoin Adress considered even or odd?


texts: What is expected of current mining equipment 2 years from now?

texts: I am curious if I buy a miner  today what good would be two years from now, will it still mine the same way and also still be profitable? Assuming that the difficulty factor is adjusted to the way that it mines.


texts: Specific namecoin address in merged mining

texts: I want to do merged mining with P2Pool, and I want any generated namecoins to go to a specific namecoin address in my wallet. I haven't seen a way to configure this in P2Pool or namecoind, and Google's turned up no hits. It seems as though it's either too obvious for anybody to mention in any guides, or like I'm the only one who wants to do this. If the latter, then why does nobody want this and why should I not do this?


texts:
When the Master Private Key and the Master Public Key are generated, can I disclose the chain code as say BIP32? If not, how can is possible verify a child public key with public parameters?

This is an important question for me because it's necessary give the possibility to verify the generated child public key to another user in my scenario.

Could the Master Private Key generated by using a random integer 0< k < n where n is the curve group order?


texts: Why do transaction/blockchain based gambling sites use such complicated methods for proving fairness?

texts:
Doesn't the block hash or the transaction id provide enough entropy
(for example, by using block_hash % 37 to generate a random number between 0 and 36)?

Block Chain Roulette determines the lucky number as a function of the hash of newest block in the chain:

  Everytime a new block is created on the Bitcoin block chain, the roulette wheel is spun and a random number between 0 and 36 is generated... random hash = hmac_sha512(secret hash, block hash) ...
  the random decimal integer is then multiplied by 37 and divided by (72057594037927935 + 1), decimal places dropped, resulting in a number between 0 and 36. 14 hex charecters are used because this represents a maximum random number of 72057594037927935, a number which is divisable equally by 37 (Or at least very very close to being equally divisable, when working with such large numbers). This ensures each number between 0 and 36 has an equal probability of being chosen. Continue reading...

SatoshiDice determines win/lose by using a pre-determined secret as well:

  The lucky number used to determine the winner of games is simple. It is simply the first bytes of hmac_sha512(secert,txid:out_idx). That would be the secret string as the key and the transaction ID of your bet transaction as the data.

Can someone generate a transaction in such a way that its hash is known ahead of time?
Edit: It seems like the second part of the question has already been answered.


texts: Can you see live trade data on the blockchain?

texts: I am reading a lot about quantum trading, and machine learning, and am looking for data sources to train my algorithms. I an curios to see if there is a way to see live exchanges on the bitcoin blockchain? For example if someone is trading bitcoin for ethereum or vice versa on bittrex, how would I go about seeing all of this data on the chain? I know it exists, but not sure where to look.


texts: Bitcoin-core how to get all transactions hashes?

texts:
Please, can anyone help me how to get all transactions hashes? How to browse all the transactions hashes used in blockchain?

P.S. How simply get a list of all transactions IDs (as a simple text list) if I only have running syncronized bitcoin node on my PC and I do not have any other data such as addresses or something else?


texts: How is mining associated to blockchain transactions?

texts:
I know how mining works and how transactions are added to the blockchain. What I don't understand is the association between the two...if any.

I've read a few times about how a cryptocurrency transaction is added to the blockchain through consensus. This often means PoW. Then there is mentioned that miners perform PoW and the transactions are cleared. How?

Miners mine for coins right? What does mining have to do with verifying unrelated transactions?

At least for bitcoin, is it even possible for miners to keep up with all of the transactions occurring?


texts: What is the Bitcoin address to fill in under 'Pay to'

texts: I have a Bitcoin Core wallet. I do not know what address is required under 'Pay to'. Is it one I must create or what?


texts:
I am just starting to understand the internals of bitcoin. I am a CS graduate and familiar with most bitcoin terminologies. I've read Satoshi's paper and researched the question but I couldn't find the answer.

Now that it is much more profitable to mine blocks for the reward (25coins) than the transactions fees. my question is what prevents miners from only including 1 (or 0 if its allowed) transactions in their generated blocks as hashing smaller data will result in greater hashes/s (yes?)

Also, and most importantly is how does a miner decides that enough transactions has been received and start finding the nonce as adding a new transaction to the attempting block will result in all the work done for this block as obsolete.

I'll try to give my guess so correct me if I am wrong. While the miner tries to find the new block it buffers any received new transactions. If he/she finds the new block or a a new valid block is received they start working on the next block by putting all the buffered transactions into a new block and get to work.

Please excuse me if my questions seems primitive. I tried my best to research and any links are greatly appreciated.
Thanks.


texts: Can we drive the bitcoin transaction fee arbitrarily close to zero by keep increasing the block size limit?

texts: Can the bitcoin scalability problem be solved in the long run by increasing the block size limit (either dynamically or statically)?


texts: How to make concurrent calls to bitcoin core rpc?

texts:
I am trying to call getBlock for 100k blocks, but it is too slow to call them sequentially. This is what I am trying. I have a full node of bitcoin core running. I set the -rpcthreads=100 and -rpcworkqueue=100, and I use js to make Promise.all([multiple rpc calls]). To my understanding, rpcthreads allows concurrent calls, but maybe I misunderstood it. I expected the time it takes to run 2 getblock to be similar of running 1. However, I am not seeing a huge performance increase (running 2 roughly takes double the time). What is the correct way to make bitcoin core accept concurrent rpc requests? Thanks!

my bitcoin core config: -server -rpcuser=un -rpcpassword=pw -txindex=1 -rpcthreads=100 -rpcworkqueue=100

my attempt to make it concurrent (client being a wrapper class around the rpc api.):

const before = Date.now();
await Promise.all([
  client.getBlock('0000000000000000000119e179a3169afe7e1dbd867cb9070a6f75a583b98fb3'),
  client.getBlock('0000000000000000000119e179a3169afe7e1dbd867cb9070a6f75a583b98fb3')
]);
const afterAll = Date.now();

console.log('time for all');
console.log(afterAll - before);


texts: Virtual currency used as alternative currency

texts: Would it be feasible for a virtual currency to be used in the same way as alternative currencies such as Berkshares and Brixton Pounds ? Furthermore, do you think it is possible to make it independent of conventional currencies such that it is held to a standard, say a basket of household goods ?


texts: Is there a maximum factor by which difficulty can change?

texts: I seem to recall, long ago, being told that difficulty couldn't change more than a certain amount at each retarget, but I can't seem to find what that factor is (or even confirmation that such a factor exists) no matter how hard I google. Does such a factor exist and if so what is its value?


texts: Share blockchain data between bitcoin-core and btc-1

texts: I am currently running a BTC-1 node and would like to setup an additional core node before the November fork. Ideally, I would avoid the need to resync the entire blockchain again. Is it possible for me to locally copy the blockchain data I have already downloaded for btc-1 and use it to avoid a full resync with bitcoin-core?


texts: How Bitcoin decide which scriptPubKey use?

texts:
I'm studying Bitcoin protocol, and I'm able to create address by my bash script.
The addresses "P2PKH" and "P2PK" have the same procedure.
Compressed or uncompressed public key – SHA256 – RIPEMD160.
When I create a transaction using createrawtransaction I can see that the protocol use P2PKH validation by default, and in listunspent I can find its scriptPubKey.
My question is: How the protocol (and where in the code) recognize the validation? I'd like to understand when the protocol add
OP_PUSHBYTES[33] PBKEY OP_CHECKSIG instead of OP_DUP OP_HASH160 OP_PUSHBYTES[20] HASH160(PB) OP_EQUALVERIFY OP_CHECKSIG and How can I use P2PK instead of P2PKH?
UPDATE
For istance, my address is: (testnet)
mwqCgoJBcyciRUawXerkvom8sbg3zkjrvV
Import my address (I don't have it in my wallet, I created this address from outside of bitcoin-core)
bitcoin-cli importaddress mwqCgoJBcyciRUawXerkvom8sbg3zkjrvV

then I mined 101 blocks
bitcoin-cli generatetoaddress 101 mwqCgoJBcyciRUawXerkvom8sbg3zkjrvV >> /dev/null

After that I check my UTXO:
bitcoin-cli listunspent 1 101 '["'mwqCgoJBcyciRUawXerkvom8sbg3zkjrvV'"]'
[
  {
    "txid": "531dcfeea3f87feb4101bfea6fe91ffb0262072cb27acc56f885677ccca089cd",
    "vout": 0,
    "address": "mwqCgoJBcyciRUawXerkvom8sbg3zkjrvV",
    "label": "",
    "scriptPubKey": "76a914b2f58389a224c2fac62b51e78aad7ed058b50f5f88ac",
    "amount": 50.00000000,
    "confirmations": 101,
    "spendable": false,
    "solvable": false,
    "safe": true
  }
]

retrieve the UTXO
bitcoin-cli getrawtransaction 531dcfeea3f87feb4101bfea6fe91ffb0262072cb27acc56f885677ccca089cd 2 | jq

...
{
      "value": 50,
      "n": 0,
      "scriptPubKey": {
        "asm": "OP_DUP OP_HASH160 b2f58389a224c2fac62b51e78aad7ed058b50f5f OP_EQUALVERIFY OP_CHECKSIG",
        "hex": "76a914b2f58389a224c2fac62b51e78aad7ed058b50f5f88ac",
        "reqSigs": 1,
        "type": "pubkeyhash",
        "addresses": [
          "mwqCgoJBcyciRUawXerkvom8sbg3zkjrvV"
        ]
      }
    },

...

Why I have P2PKH instead of P2PK? And how can have the hash of my Public key if I imported just address (HASH160(PB))? And the last question, I understand that if the wallet find the 1 as the first char it apply P2PKH by default. How Can I use P2PK instead (study purpose).


texts: How does bitcoin reward who find the block?

texts:
After getting the getblocktemplate, hashing it, finding a solution and generating the proper message to submit to the blockchain, if i ever solve a block how does the network knows it was me and properly give the reward to my wallet?

i heard somewhere that i need to append a transaction sending 12.5 BTC to myself before generating the message, if that is true what does prevent anyone of generating more than one transaction and append before solving a block?

Does getblocktemplate coming from my bitcoin-cli already generates this transaction for me?


texts: Why have my funds in Bitcoin Block Explorer's online wallet decreased in value?

texts:
I feel I may have been cheated by Bitcoin Block Explorer whose URL is http://blockchain.info

Here's the background:

I am using the online wallet provided by Bitcoin Block Explorer. It contains 1.5 BTC.

According to the website http://blockchain.info/stats, the weighted average price is 134.19 USD for 1 BTC on September 11. It means that my 1.5 BTC  is worth 201.29 USD.

However after logging in to my wallet, on the top right-hand corner, the USD equivalent shows 186.18 USD. It means the weighted average price is 124.12 USD.

Could some experienced guy explain to me the discrepancy?

Added a second question

After going through the comments posted here, a second question comes to mind.

An online merchant gives his customers the option of paying using one of the following methods: Visa, PayPal or Bitcoins.

The price of the product is 50 Euros if the buyer uses Visa or PayPal to pay but 0.52 BTC if he chooses the Bitcoin payment system.

According to some posters here, Bitcoin/USD rates vary across exchanges.

My question is: if I am the customer, how can I be sure that I am not overcharged if I use Bitcoins to pay? (0.52 BTC may worth more than 50 Euros)


texts:
This is probably a stupid question that has an answer somewhere, but I was unable to find anything, so please feel free to redirect me !

I have a basic understanding of how the bitcoin blockchain works, namely, you sign and broadcast your transaction, it gets picked up by the nodes and is eventally included in a block that is mined.

I understand that as long as there isn't someone controlling more than 50% of the mining power, it is unlikely to be able to perform a double spend attempt.

However, what prevents someone from spending more bitcoins that they have ? For example, if I have 1 BTC on my adress, suppose I run a mining node, what prevents me from trying to mine a block in which I spend 1.2 BTC ? At what point in the process is the balance of my adress checked to make sure I do have the bitcoin that I want to spend ?

At first I thought that it was the nodes that verified that the transaction on the mempool are valid before starting to mine them but this can't be it, since you could have a malicious node that does whatever (although it would be difficult to pull off without enough mining power).

This check must be somehow "hard-coded" somewhere, in the sense that it is actually impossible to create a transaction of inexistent bitcoin. Could someone point me to a resource or elaborate how does this work ?


texts: What security threats does blockchain technology solve or present?

texts:
I am interested in security, identity and authenticity in electronic networks.

What sort of security concerns could blockchain technology help with and what sort does it pose?

Are there entry and exit security concerns?


texts: Exporting private key from expired bitcoin address (now showing as watch-only)

texts: Is there a way, in theory, to export private key from the bitcoin address (watch-only) that is now expired, but used once before? (even to get a different format of that key, numeric one instead of QR code used in the first place?). If everything is traceable, out of curiosity - has anyone ever managed to actually do this?


texts: How does Coinbase / GDAX calculate volume in historical candles?

texts:
How does Coinbase/GDAX calculate the "Volume" in candle data?

I'm pulling data from the GDAX API in 2 ways; 1, by requesting candles similar to this endpoint, and 2, by tallying up raw tick data from the GDAX WebSocket.

My problem is that when I try to create candle data from tick data, my volumes are very different than what GDAX reports for the same/similar periods. (See the blue and red outlines below...)

In my hand-made candles (shown below, highlighted red), I'm simply taking the sum of all the BTC transacted during that interval, but the numbers are much higher than what GDAX is reporting in similar periods.

What am I doing wrong?

Here's the format I'm using to make my candles:

While researching this, I found this post saying that Coinbase uses the # of transactions to calculate volume, but I tried that, and the numbers are still way off. I even tried dividing and multiplying the # of transactions with my calculated volume, but they're still way off.


texts: What precautions should be taken to protect a Ripple wallet?

texts:
What if a Ripple wallet gets hacked?
What are the suggested precautions for the average user?


texts: How often does a typical miner refresh their candidate block?

texts:
I realize that this is a general question with no "correct" answer, as every miner can operate differently.

Having said that, I'd like to be able to display a list of transactions that would be considered a fair representation of the transactions in the memory pool that are poised to be mined.

So far I have been:

Using getblocktemplate to get the list of transactions.
Refreshing the list when a new block arrives, or at 1 minute intervals.

Using getblocktemplate seems logical, as I imagine the majority of miners would like to get the most amount possible in fees from their blocks.

I'm then guessing that miners would want to refresh their candidate block at certain intervals to check for higher-fee transactions in the mempool.

Is it likely that miners would be inclined to refresh their candidate blocks much more (or less) than every minute?


texts:
Recently, WIRED released an article about an alleged creator of Bitcoin being raided by the police. Briefly, the article mention the following:

  Police raid home of bitcoin 'founder' Craig Steven Wright
  09 December 15

  Police have raided the home of a 44-year-old Australian alleged to be
  the creator of cryptocurrency bitcoin.
  Craig Steven Wright, a tech
  entrepreneur living in Sydney, was labelled by WIRED US as the
  mysterious 'founder' of the digital currency -- that has previously
  only been known under the pseudonym Satoshi Nakamoto.
  Since Wright
  was named as being the potential originator behind bitcoin police have
  raided his home and office, although the Guardian reports the raids
  surround tax issues and not the bitcoin revelations specifically.

1) What crimes Satoshi Nakamoto has done in order to be chased by the police? This applies only to Australia or around the globe?
2) Nowadays there are several hundreds of other cryptocurrencies. All those developers are also liable of such punishments?


texts: Is it doable to supplant the current Bitcoin Core implementation with another rewritten in a different language?

texts:
Can Bitcoin Core be rewritten in another language, let's say Rust, and could such an implementation supplant the current one in C++ without the users of Bitcoin experiencing some sort of reset/lost of funds?
Languages come and go and I was thinking that decades ahead the world may be in the similar situation with respect to C++ as it is today with respect to Fortran.


texts: bitcoind crashing due to insufficient memory?

texts:
EDIT 3

Bumping my VPS to 1GB of physical RAM stopped the crashing issue... UNTIL said VPS ran out of disc space.

I added prune=10240 to my ~/.bitcoin/bitcoin.conf file such that the blockchain file would start pruning transaction history upon reaching 10GB filesize (1024 MB * 10 = 10GB).

EDIT 2

This seems to be a memory issue, not a VPN networking issue. I turned OpenVPN off and restarted bitcoind only to see it silently crash again.

I've now added a 1GB swapfile to expand the available memory space (risk is this will cause performance issues for the OS). Will update once again if this solves the issue. If not, I will probably end up trying to upgrade the VPS instance to 1GB of physical RAM from 512MB.

EDIT
Found some interesting stuff in the log relating to tor...

root@sf-vps:~# cat ~/.bitcoin/debug.log | grep tor -i
2016-11-13 16:52:21 Default data directory /root/.bitcoin
2016-11-13 16:52:21 Using data directory /root/.bitcoin
2016-11-13 16:52:21 Using at most 125 connections (1024 file descriptors available)
2016-11-13 16:52:29 torcontrol thread start
2016-11-13 17:08:43 Default data directory /root/.bitcoin
2016-11-13 17:08:43 Using data directory /root/.bitcoin
2016-11-13 17:08:43 Using at most 125 connections (1024 file descriptors available)
2016-11-13 17:08:50 torcontrol thread start
2016-11-13 17:08:50 tor: Error connecting to Tor control socket
2016-11-13 17:08:50 tor: Not connected to Tor control port 127.0.0.1:9051, trying to reconnect
2016-11-13 17:08:51 tor: Error connecting to Tor control socket
2016-11-13 17:08:51 tor: Not connected to Tor control port 127.0.0.1:9051, trying to reconnect
2016-11-13 17:08:52 tor: Error connecting to Tor control socket
2016-11-13 17:08:52 tor: Not connected to Tor control port 127.0.0.1:9051, trying to reconnect

I've installed the Bitcoin software on Ubuntu 16.04. I'm able to run bitcoind -daemon for a few minutes, but after a while the process crashes.

Interestingly, I don't see any reasons in ~/.bitcoin/debug.log explaining why the program might have terminated.

I suspect a couple of things:

Not enough disc space to store the entire blockchain. However, I don't think this is the case as running df - h shows a combined total of only ~41% disc consumption:

root@sf-vps:~# df -h
Filesystem      Size  Used Avail Use% Mounted on
udev            241M     0  241M   0% /dev
tmpfs            50M  3.1M   47M   7% /run
/dev/vda1        20G  6.3G   13G  34% /
tmpfs           247M     0  247M   0% /dev/shm
tmpfs           5.0M     0  5.0M   0% /run/lock
tmpfs           247M     0  247M   0% /sys/fs/cgroup
tmpfs            50M     0   50M   0% /run/user/0

Server is not able to receive inbound messages as I'm running a VPN. Is it possible that I'm experiencing a networking issue, e.g. inbound traffic to port 8333 (the default for bitcoind) is not being allowed through my VPN? I can't remember how to change the VPN config to allow connections on specific ports, but that's where I'm looking next...

root@sf-vps:~# netstat -nr
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
0.0.0.0         159.203.240.1   0.0.0.0         UG        0 0          0 eth0
10.8.0.0        10.8.0.2        255.255.255.0   UG        0 0          0 tun0
10.8.0.2        0.0.0.0         255.255.255.255 UH        0 0          0 tun0
10.12.0.0       0.0.0.0         255.255.0.0     U         0 0          0 eth0
159.203.240.0   0.0.0.0         255.255.240.0   U         0 0          0 eth0

Thanks in advance for your help :)


texts: Why does Bitcoin-Qt not launch the program, on Mac

texts:
I can't believe that I have lost my Bitcoin Wallet just because I clicked on the red spot on the window of it on my Mac. Or was this enough to loose it???

I think I have the address (does it start with a 1xxxx ?) and I have my password.
Have I lost my wallet or is it just invisible?

When I click on the Bitcoin-QT icon in my applications folder, nothing happens.


texts: What are the perceived advantages that bitcoin has over other currencies or other ways of sending money?

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

Suppose that the value of Bitcoin in USD magically remained constant from this day forward. What unique advantages does Bitcoin has other its alternatives (e.g. USD, Paypal)


texts: Coinbase lost my transaction from Bitstamp

texts:
I'm moving my coins out of Bitstamp I was looking for another exchange. I have sent 0.00007 BTC to just test the transaction. I got the address where I want to send coins to from coinbase.com/myAccountName. Apperently this address changes after a while.

I got a mail from Bitstamp to verify my transaction, what I accepted.

  You requested to withdraw 0.00007000 bitcoins to address
  1Kr8jaHPqEfwd1ZXMh6PHg2fhM5vqCYAQH.

A few minutes after my transaction it was finished on Bitstamp. I copied the address to the blockchain and I saw it was confirmed and verified my the network.

Then I went back to coinbase.com/myAccountName and I saw the address was changed...
I never got a mail or a conformation the funds have been transferred on my coinbase account.

I thought Coinbase was doing a lot of effort to make this dummy proof?
What did I do wrong? Isn't coinbase.com/myAccountName made to do an easy transfer?

I'm using Bitfinex now, worked great. Very happy with the exchange!


texts: Raw data of dates in all blocks using PHP or R

texts:
Is it possible to obtain the date (time stamp) of each bitcoin block so far, using languages like PHP or R?.

I am developing an analysis of the time series of bitcoin use for a scientific project, and while many sources provide averages, few provide the raw data.

In I related post (Raw data of transactions in all blocks), a person (amaclin) kindly provided the number of transactions in all existing blocks, could it be possible to obtain the date?.

Is this something that can be done in R or PHP?


texts: exploring a local copy of the namecoin blockchain?

texts: I installed electrum-nmc as a namecoin software and download blockchain in my computer. where I can find local copy of namecoin blockchain?


texts: How to find bitcoin balance via command line

texts: I'm wondering how to find the balance a wallet for a full node on a command-line only linux box.  bitcoin-cli doesn't seem to help here, and I'm not sure what else to try.


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occasionally on Android we are generating an ECDSA signature. This turns out to have a "r" length of 31 bytes. Is that valid?

For reference here is a nice diagram outlining the ASN.1 structure of such a signature:

how do you figure out the r and s out of a signature using python

Best regards, Rene


texts:
I would like to understand the cryptocurrency zcash a little bit better...

My understanding of it is that there are two address types t-addresses and z-addresses. Only transaction between two z-addresses are fully private. Transactions between t-addresses are working as transactions in bitcoin, i.e. the degree of privacy is exactly the same. Also there are two different pools: shielded pool and unshielded pool.

My questions:

Zcash is based on a base currency. As far as I know it is bitcoin, right?
I guess the coins in the shielded pool are zcoin, right?
How about the unshielded pool? Are they bitcoins or zcoins? (i.e. the marketcap of zcoins consists only of the coins in the shielded pool or both pools?

Thanks a lot for any kind of help!


texts: How come that there can be many transfers in a single Bitcoin transaction?

texts:
In Ethereum one transfer has one transaction ID. How come there can be many transfers in a single Bitcoin transaction? For example, in this transaction:
https://blockchain.info/tx/d98491f6697955d9bdb565587a6ae021723a52d5c86a3be04a3f3027329a7175


texts: If using Bitcoins in a real world brick and mortar store, a customer presents a paper with a QR code, merchant scans QR code and deducts purchase cost from Bitcoin total presented. How can merchant print change receipt in a timely manner, <10 , if you have to wait for another block creation?


texts: Why couldn't bitcoin be hosted on the internet?

texts:
I was wondering why bitcoin wasn't hosted on the internet? Why create a completely separate decentralized network, I thought the internet was already decentralized. For example, couldn't they have rented a few amazon ec2's or some other servers hosted on xyz host and call it a day?

(Sorry for newb question)


texts: How can there exist businesses that "specialize in blockchain analysis looking for patterns of usage that reveal how money is being used"?

texts:
I read this today in a SE comment for an unrelated question:

  there are businesses that specialize in blockchain analysis looking for patterns of usage that reveal how money is being used.

To me, this is downright offensive, since I have spent 20 years trying to come up with something that I can do that will actually generate money.

And now somebody claims that there are entire actual businesses that do nothing but analyze the Bitcoin blockchain looking for patterns, and somehow make money from this?

Can somebody explain to me how this makes them money? And what, more precisely, do they do when they "look for patterns"? Surely this must involve more than just having a Bitcoin Core fullnode on a PC and looking at the blocks locally?


texts: How are transaction fees calculated in raw-transactions?

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So, after understanding how to create and send raw transactions on the basis of 'How to send from many bitcoin addresses to one bitcoin address?', in practice I still struggle with transaction fees. For example, I do the following in order to calculate the size of an hex-encoded transaction:

hex_raw_transaction = createrawtransaction(...)
hex_raw_transaction = signrawtransaction(hex_raw_transaction)
byte[] size = HexStringToByteArray(hex_raw_transaction)
int transaction_size = size.Length

Is that a correct way to determinate the transaction size? (Regarding to https://en.bitcoin.it/wiki/Transaction_fees)?

Is it correct that the transaction fee is set by the unassigned amount in the outputs?

For example, if I have 1 BTC in one address and send the 0.65 BTC to a second address and 0.3495 BTC as change to the first

//The fee will be:
fee = 1 - (0.65 + 0.3495)  //= 0.0005 btc

is it correct that the fee will be 0.0005 BTC?


texts: Can Bitcoin be "shutdown" if energy consumption for mining is heavily regulated?

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Can Bitcoin be "shutdown" or heavily hampered if energy consumption for mining is heavily regulated? Can transactions still be processed if mining for new coins is hampered? I am thinking it would be easy to detect illegal mining just like they detect illegal drug-plant farms from the massive use of energy used to power the solar lights. Would BTC survive with only minor mining going on?

It is quite obvious that if BTC will start to consume more energy than USA than people might be, if nothing else, a bit concerned about the environmental effects.

If BTC won't survive, has Ethereum with the future proof-of-stake concept a better chance of surviving government clamp-down?


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We know that, for security and anonymity, we shouldn't reuse addresses. Also, there is the idea of change avoidance to protect ourselves from any number of change detection heuristics.

But I find that unspent change addresses ("UTXO's") are often unavoidable. Especially when using other privacy-enhancing techniques, such as equal-output CoinJoins, where you end up with many source addresses.

Is there a good technique to be able to spend these UTXO's without compromising privacy?


texts:
I have the following transaction on the testnet:

dc5b627a93ffaca1fe02a4352406c218be17fc3e6d47cfefe7e3890037b689ad

It shows like this:

Notice that the amount is 1993.07(..) TBTC

With BitcoinD, I received the following:

Status: 90 confirmations
Date: 12/13/2017 15:56
From: unknown
To: mz7XHbwYAnfZhmMqSsgDDPpFmSuxV2i6UF (own address, label: 5f40098e-0e0d-b642-62a2-cc966775ce7f)
Credit: 0.00859375 BTC
Net amount: +0.00859375 BTC
Transaction ID: dc5b627a93ffaca1fe02a4352406c218be17fc3e6d47cfefe7e3890037b689ad
Transaction total size: 249 bytes
Output index: 0

But the amount is: 0.00859375 TBTC

Why is this?


texts: What happens to wallet.dat if I uninstall and re-install on Windows Bitcoin desktop client?

texts: If I uninstall Bitcoin Core desktop client, what happens to the wallet.dat? Is this erased or left in place? If I install Bitcore Core desktop again, does my wallet.dat get overwritten?


texts: Is instant profitable arbitrage impossible?

texts:
Case #1: Trade coins after an arbitrage opportunity appears.

Buy Coin B with Coin A at a low price.
Move Coin B to the buyer's market.
Sell Coin B for Coin A at a higher price.

However, transaction fees, withdrawal fees, the time withdrawals take, and the presence of other arbitrage bots ruin its success. I've monitored the market for opportunities and tested this case, and so far I've only found the impracticality of it: stuck-withdrawals, opportunities that disappear, transaction minimums and fees, etc...

Case #2: Hold 50/50 coins and instantly trade them.

This case puzzles me. It is simply not practical.

There are over one hundred alt-coins of which one would have to have funds.
Apart from the alt-coin opportunity funds, one would need a proportional amount of LTC & BTC.
Most (if not all) of the alt-coins' value is volatile. It makes no sense to steadily hold funds in those "currencies". Whatever small gains acquired by arbitrage would soon dilute.
If one had the hundreds of alt-coins required, and some (mysterious) way to manage their volatility. The size of the arbitrage opportunities available wouldn't match the ROI a traditional investment offers.

Edit 1: Nitpicking the issue, it is possible to perform arbitrage on counted occasions. But I'm referring to the fact that #1 is not instant, and it's riskier and possibly not profitable. And case #2 is flawed in the sense that is not straightforward to hold (and increase) value in a portfolio of crypto-currencies.

I've seen some "professional" crypto-coin arbitrage services, but they look more like scams than anything else. Is there any truth to crypto-coin arbitrage? Is there a case #3, 4, 5, ..., n?