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Showing 19 of 19 results by mnemonix
That's very interesting ... As I know, satoshidice does exactly the same ... They send the won bitcoins to the sender address back.
I havn't heared of any problems yet ... Do you know more you could tell me about?
I havn't heared of any problems yet ... Do you know more you could tell me about?
There have been a few topics raised by people who sent money from a Mt. Gox (or other similar) account to SD which means the returns went to Mt. Gox rather than the user (and apparently there are warnings on the SD page about not using web wallets).
Okay, understood ... This will make my engine much more easier, because I don't have to keep a full transaction index and I don't have to watch my transaction list ...
It's often the case that something is quite difficult to solve when choosing an unnatural way to solve the problem ...
Quote
Yes - that would be the much preferred approach (and *please* don't send back 1 satoshi + fee *signals* like SD does when you lose).
You mean the bitcoin network flooding of small-ammount transactions?
There's also a Testnet Faucet at https://tpfaucet.appspot.com/, as well as a simple web-based hosted testnet wallet.
Thank you very much! Good to know about!
Also understand that in general for people using web wallets the UTXO source addresses are *not* their own addresses at all (so sending back to them would actually just be sending money to the service rather than a user of it).
That's very interesting ... As I know, satoshidice does exactly the same ... They send the won bitcoins to the sender address back.
I havn't heared of any problems yet ... Do you know more you could tell me about?
This "sending back to sender" is crucial for my development project and it would be good to hear of problems in advance
*edit*: ah, here is a interesting discussion about ... it seems you are very right and I should give the opportunity to specify an address to which the money is sent after being processed by my engine ...
https://bitcointalk.org/index.php?topic=77870.120
bitcoind listtransactions "*" 1 X
for x starting at 0 and increasing by 1 until the result matches a transaction I've already encountered before
for x starting at 0 and increasing by 1 until the result matches a transaction I've already encountered before
Genius!
Not really ... Not only, he generates lots of RPC calls, but he will also miss transactions if a new transaction comes in while he increments X ...
Example:
bitcoind listtransactions "*" 1 0
{... hash: "fe46e7a8..."' }
while
bitcoind listtransactions "*" 1 1
{... hash: "fe46e7a8..."' }
So, you would break here although, there could be another new transaction after the hash you already know ...
Imho this listtransaction model is crap ... it make things much more difficulty than it has to be. The newest transaction is always at index 0 is stupid ...
Finally figured it out with bitcoinj ...
The code outputs correctly "mkMUgWeh3mfpgvKgjK81rUMqKfNoww7tie" (txid: 1d893276bcae417e39aa08b60d02c9b3d4d5e2380aba6bcf359b6d752923ae9f)
Code:
private static String s="483045022001bef6b42a6a7cb4dfac6ce93982b0d0a0f3bf0fe55134c278e2a6726d11c596022100fec6b4acd6364007334ec6359a5a5bdde055624824de5f8c0dca064564856f51012103a097b85e726f5e66232c33da2eca4bb0936d8d30a4c721abd0a1717cc5c06708";
public static byte[] hexStringToByteArray(String s) {
int len = s.length();
byte[] data = new byte[len / 2];
for (int i = 0; i < len; i += 2) {
data[i / 2] = (byte) ((Character.digit(s.charAt(i), 16) << 4)
+ Character.digit(s.charAt(i+1), 16));
}
return data;
}
/**
* @param args
* @throws ScriptException
*/
public static void main(String[] args) throws ScriptException {
TransactionInput tin = new TransactionInput(NetworkParameters.testNet3(), null, hexStringToByteArray(s));
Address a = tin.getScriptSig().getFromAddress();
System.out.println(a.toString());
}
public static byte[] hexStringToByteArray(String s) {
int len = s.length();
byte[] data = new byte[len / 2];
for (int i = 0; i < len; i += 2) {
data[i / 2] = (byte) ((Character.digit(s.charAt(i), 16) << 4)
+ Character.digit(s.charAt(i+1), 16));
}
return data;
}
/**
* @param args
* @throws ScriptException
*/
public static void main(String[] args) throws ScriptException {
TransactionInput tin = new TransactionInput(NetworkParameters.testNet3(), null, hexStringToByteArray(s));
Address a = tin.getScriptSig().getFromAddress();
System.out.println(a.toString());
}
The code outputs correctly "mkMUgWeh3mfpgvKgjK81rUMqKfNoww7tie" (txid: 1d893276bcae417e39aa08b60d02c9b3d4d5e2380aba6bcf359b6d752923ae9f)
Hi all,
I've been fighting with jsonrpc and bitcoind for about 2 days ...
I still have the problem that I can't determine the sender address of received payments.
One easy solution would have been to simple grab the VOut of the previos transaction and extract the sender from there but bitcoind doesn't save transactions for which there are no private keys in the wallet. And I didn't figure out how I could motivate bitcoind to ask the p2p-network for details to a transaction with hash=X.
Currently, I know the pubkey of the sender has to be in scriptsig somewhere but it seems to be impossible to extract it from there.
After googling a lot, I didn't find any sample codes extracting the hash and converting it to a base58 address.
Coule someone please give me some tips?
Thank you in advance!
All the best,
Thomas
I've been fighting with jsonrpc and bitcoind for about 2 days ...
I still have the problem that I can't determine the sender address of received payments.
One easy solution would have been to simple grab the VOut of the previos transaction and extract the sender from there but bitcoind doesn't save transactions for which there are no private keys in the wallet. And I didn't figure out how I could motivate bitcoind to ask the p2p-network for details to a transaction with hash=X.
Currently, I know the pubkey of the sender has to be in scriptsig somewhere but it seems to be impossible to extract it from there.
After googling a lot, I didn't find any sample codes extracting the hash and converting it to a base58 address.
Coule someone please give me some tips?
Thank you in advance!
All the best,
Thomas
Re: Official Open Source FPGA Bitcoin Miner (Last Update: April 14th, 2013)
Thx for your work you put in the miner!
I ported the Xilinx_VHDL miner to the ml605 dev board.
Actually, straight forward ... Replaced the dcm with a newer Virtex6-aquivalent, wired the pins to rs232 and clock, adjusted the baud rate and it run instantly.
It does 200MHash/sec and is user by about 85% ...
I ported the Xilinx_VHDL miner to the ml605 dev board.
Actually, straight forward ... Replaced the dcm with a newer Virtex6-aquivalent, wired the pins to rs232 and clock, adjusted the baud rate and it run instantly.
It does 200MHash/sec and is user by about 85% ...
Hat sich erledigt Jemand war so nett, mir ein paar Testcoins zu schicken
Hallo,
hat jemand ein paar Test-Net-Bitcoins, die er mir schicken könnte?
Meine Adresse: mi21Tg2i2j6sjnVgExX5tYw8Yc71rDEqqy
Ich weiß, dass man sie im Testnet einfacher minen kann. Leider dauert das aber um die 120 Blöcke, bis die Coins confirmed sind ...
Danke für eure Hilfe!
Viele Grüße,
Thomas
Jemand war so nett, mir ein paar Testcoins zu schicken hat jemand ein paar Test-Net-Bitcoins, die er mir schicken könnte?
Meine Adresse: mi21Tg2i2j6sjnVgExX5tYw8Yc71rDEqqy
Ich weiß, dass man sie im Testnet einfacher minen kann. Leider dauert das aber um die 120 Blöcke, bis die Coins confirmed sind ...
Danke für eure Hilfe!
Viele Grüße,
Thomas
Hi all,
does someone have some testnet-bitcoins he could send me?
I know, I could generate some on the testnet but it would take quite a time to get enough confirmations in order to use them:
My address: mi21Tg2i2j6sjnVgExX5tYw8Yc71rDEqqy
Thank you very much in advance!
Thomas
does someone have some testnet-bitcoins he could send me?
I know, I could generate some on the testnet but it would take quite a time to get enough confirmations in order to use them:
Quote
The classic bitcoin client won't show generated coins as confirmed until the 120th block.
My address: mi21Tg2i2j6sjnVgExX5tYw8Yc71rDEqqy
Thank you very much in advance!
Thomas
Thank you for your replies ...
Wow, what a waste of addresses
Does someone know an estimation of the number of all transfers in $ ever? I hope it is far away from 2^160
But you are right ... This seems to be the way ... Generating a private address only the buyer can know ...
Thank you!
Best regards,
Thomas
Wow, what a waste of addresses
Does someone know an estimation of the number of all transfers in $ ever? I hope it is far away from 2^160
But you are right ... This seems to be the way ... Generating a private address only the buyer can know ...
Thank you!
Best regards,
Thomas
Hi,
Assuming something like e**Y. Peter buys something for an amount of 100BTC and has to send Fritz money. How can Fritz distinguish Peter's payment from other payments?
Peter could tell Fritz his bitcoin-addr he will use, but it is very likely that Peter won't even know his own address which will be used for the transfer, because the bitcoin client may combine coins from 5 or 10 or more different addresses out of Peter's wallet.
How can Fritz be certain of receiving coins from Peter?
Another difficulty ... Assume there is a 3rd party which is monitoring the transfer (e.g. like e**Y which can acknowledge, the transfer has been completed like p*yp*l instant payment notification)-
How could the system be sure that Peter transfered all coins to Fritz?
I would very appreciate any help I can get on this ...
All the best,
Thomas
Assuming something like e**Y. Peter buys something for an amount of 100BTC and has to send Fritz money. How can Fritz distinguish Peter's payment from other payments?
Code:
(10BTC) IN1-|------------|
(20BTC) IN2-| |
(5BTC) IN3-| TX |-OUT1 (100BTC)
(35BTC) IN4-| |-OUT2 (5BTC Change)
(35BTC) IN5-|------------|
(20BTC) IN2-| |
(5BTC) IN3-| TX |-OUT1 (100BTC)
(35BTC) IN4-| |-OUT2 (5BTC Change)
(35BTC) IN5-|------------|
Peter could tell Fritz his bitcoin-addr he will use, but it is very likely that Peter won't even know his own address which will be used for the transfer, because the bitcoin client may combine coins from 5 or 10 or more different addresses out of Peter's wallet.
How can Fritz be certain of receiving coins from Peter?
Another difficulty ... Assume there is a 3rd party which is monitoring the transfer (e.g. like e**Y which can acknowledge, the transfer has been completed like p*yp*l instant payment notification)-
How could the system be sure that Peter transfered all coins to Fritz?
I would very appreciate any help I can get on this ...
All the best,
Thomas
Please let me out ... I found an error in the SHA256 implementation of this FPGA based bitcoin miner, but can't post in his thread:
http://forum.bitcoin.org/index.php?topic=9047.0
It leads to "10% rejected shares" ...
All the best,
mnemonix
http://forum.bitcoin.org/index.php?topic=9047.0
It leads to "10% rejected shares" ...
All the best,
mnemonix
This is not true. "minting" Bitcoins, or as we like to call it, mining, is a shared responsibility of all nodes on the network.
Ups, I think I got Satoshi's paper wrong ...
Quote
The problem of course is the payee can't verify that one of the owners did not double-spend
the coin. A common solution is to introduce a trusted central authority, or mint, that checks every
transaction for double spending. After each transaction, the coin must be returned to the mint to
issue a new coin, and only coins issued directly from the mint are trusted not to be double-spent.
the coin. A common solution is to introduce a trusted central authority, or mint, that checks every
transaction for double spending. After each transaction, the coin must be returned to the mint to
issue a new coin, and only coins issued directly from the mint are trusted not to be double-spent.
He was explaining common solutions but later he wrote:
Quote
To accomplish this without a trusted party, transactions must be
publicly announced [1], and we need a system for participants to agree on a single history of the
order in which they were received. The payee needs proof that at the time of each transaction, the
majority of nodes agreed it was the first received.
publicly announced [1], and we need a system for participants to agree on a single history of the
order in which they were received. The payee needs proof that at the time of each transaction, the
majority of nodes agreed it was the first received.
Thx for pointing me in the right direction.
Best regards,
mnemonix
How about adding a feature to the Bitcoin Client that would upon receiving or confirming a payment, send POST data to a URL that includes the amount received, address sent from, address sent to, and time received.
Also, possibly also a feature doing the same for outgoing payments.
Possibly an easier solution than API through a 3rd party.
Also, possibly also a feature doing the same for outgoing payments.
Possibly an easier solution than API through a 3rd party.
Have a block at blockexplorer.com. This site keeps track on all blocks and all transactions.
Best regards,
mnemonix
Hi,
I'm mnemonix and I'm especially interested in FPGA based bitcoin mining because I've been working quite a while with FPGAs.
I already found one FPGA miner here:
http://forum.bitcoin.org/index.php?topic=9047.0
Are there other miners out there?
All the best,
mnemonix
I'm mnemonix and I'm especially interested in FPGA based bitcoin mining because I've been working quite a while with FPGAs.
I already found one FPGA miner here:
http://forum.bitcoin.org/index.php?topic=9047.0
Are there other miners out there?
All the best,
mnemonix
Hi,
is it true, that there is a dedicated mint server which keeps track of all transactions in order to prevent double spending?
Then, isn't it also true, that some government could knock out the entire p2p-based network by just shutting down this mint server?
Best regards,
mnemonix
is it true, that there is a dedicated mint server which keeps track of all transactions in order to prevent double spending?
Then, isn't it also true, that some government could knock out the entire p2p-based network by just shutting down this mint server?
Best regards,
mnemonix
Anywayyyy...
Has anyone handled a bitbill yet?
Has anyone handled a bitbill yet?
Not yet. I thought about buying some to give family members to try to get them interested in bitcoins, but then the price went up and up and now I cant afford to.
I'm monitoring the bitcoin exchange rate and I think, the rate will go down again
Just be patientBasically, I'm referring to this thread: http://forum.bitcoin.org/index.php?topic=9047.240
But since I'm no "established user", I have no way to ask there.
Does anyone know, how Megahashs/second are counted?
I had a very close look at his FPGA-Miner source-code and i couldn't figure out how he calculated this value.
Basically, for SHA256 64 rounds of the compression-function has to be calculated and even with loop unrolling depth of 6 or 8 it takes at least clock/depth clock cycles to complete one hash ...
Could someone please explain?
Alternatively, how do I become an "established user"?
All the best,
mnemonix
But since I'm no "established user", I have no way to ask there.
Does anyone know, how Megahashs/second are counted?
I had a very close look at his FPGA-Miner source-code and i couldn't figure out how he calculated this value.
Basically, for SHA256 64 rounds of the compression-function has to be calculated and even with loop unrolling depth of 6 or 8 it takes at least clock/depth clock cycles to complete one hash ...
Could someone please explain?
Alternatively, how do I become an "established user"?
All the best,
mnemonix