How do I get my public address in Bitcoin Core?

In a world of pain at the moment. I downloaded Bitcoin Core, and before I realised I’d need the complete downloaded Blockchain, my friend transferred some coins to my address.

I did some research and am trying to import my Bitcoin core private keys to Blockchain, therefore having access to my coins. My problem is, I can’t get my public address. I have tried using several commands in the console window, and are able to unlock and lock. I’ve used ‘listaddressgroupings’ – which works, but the return is “[” and then “]” directly below?

I’ve also used getaccountaddress and getaddressesbyaccount “Your Address” with no luck.

Many thanks

bitcoind sendfrom with minconf=0

Is it possible using bitcoind JSON-RPC API to receive funds from someone and send it immediately to another third-party address? I do not want to wait for 1 confirmation.

getbalance with minconf=0 shows I have 0.01 BTC, but when I do sentfrom with minconf=0, I get Insufficient funds error.

What contributions have Blockstream developers made to the Bitcoin project?

I’m spending a lot of time debating people about Bitcoin online these days. One issue that I encounter regularly is that my opposite colloquists are unaware of the contributions the Blockstream developers have added to the Bitcoin project since the company was founded.

My aim is twofold: I’d like to be able to simply link this question next time I read “Blockstream produces only vapour, and contributes nothing”, and I think that the answer to this question deserves more visibility.

Please list what measurable contributions Blockstream developers have made to the Bitcoin project?

Segregated witness soft fork: how is the funding Tx made “ANYONECANSPEND”

Reading the BIP:

https://github.com/bitcoin/bips/blob/master/bip-0142.mediawiki

I see that the scriptPubKey in a transaction that funds a segwit redemption is the same as a normal P2PKH but merely prepended with OP_0.

Is this opcode what tells older clients that the Tx is “anyone can spend” meaning that there will be no signature data in the redemption Tx?

Of course upgraded nodes will know to look for the actual scriptSig in the witness data to verify the Tx. But how does this OP_0 fool old nodes into ignoring the scriptSig on the redemption Tx?

Is Ethereum essentially Bitcoin with Turing-complete Script?

Is Ethereum essentially Bitcoin with a Turing-complete scripting language and, if I understand correctly, where the script to be executed (not its hash) is placed in the Ethereum blockchain?

  • If so, why doesn’t Ethereum just put hashes of its scripts in the Bitcoin blockchain, send the scripts to be executed through another secure means such as via a P2P network (which would greatly reduce blockchain bloat), and avoid being an altcoin altogether?

  • If not, is the gas limit the real distinguishing feature of Ethereum compared to Bitcoin? Or is gas really Ethereum’s equivalent of Bitcoin’s transaction fees? Also, would Ethereum’s adoption of proof-of-stake further differentiate Ethereum from Bitcon?

cf. Ethereum’s white paper

(cf. the related BitcoinTalk.org thread)

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

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

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

Thanks,
David

What do pruning nodes contribute to the network?

Pruning nodes are described in the sourcecode thusly:

-prune=<n>: Reduce storage requirements by pruning (deleting) old blocks. This mode is incompatible with -txindex and -rescan.

I’ve watched that my node has been consistently uploading less than it has been downloading since I set it to run in pruning mode.

  • What services do pruning nodes still perform?
  • Do they upload blocks and transactions?
  • Can they service thin clients?
  • What can a pruning node not do, that a non-pruning node does?

bitcoin testnet daemon stuck

I am running bitcoin testnet daemon for development, but lately I have trouble with starting the daemon. Blockchain is downloaded and it seems that everything runs fine till

init message: Verifying blocks…

Verifying last 288 blocks at level 3

then it seems stuck or takes hours before doing anything. Interesting is that restarting the daemon helped me couple times and daemon started in several minutes as usual. In this time i cant obviously use RPC commands.
I dont have trouble starting mainnet daemon. Anybody has any idea what might cause and how to fix this overly long verification?