Questions tagged [bitcoin-core]
Bitcoin Core is a full node implementation of the Bitcoin protocol with a wallet and GUI. Bitcoin Core is a MIT-licensed Qt 5 GUI application for the original Bitcoin codebase. Additional/previous names include "Bitcoin-Qt", "Satoshi-Client", and "Standard Client". This tag should be used when referring to the Bitcoin Core software.
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Should I leave the Bitcoin client open?
Some people recommended that I leave my Bitcoin client open because it helps the network.
Apart from the security implications, why should I do this? I thought that miners were the ones responsible ...
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Import wallet.dat into a new Bitcoin-Qt client
I had Bitcoin-Qt on my computer with several bitcoins in my wallet, using Vista. Then my computer crashed. Finally I was able to get my computer fixed and download a new version of Bitcoin-Qt. Now I ...
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How do I import a private key into Bitcoin-Core?
How do I import a private key into Bitcoin-Qt? bitcoind is nowhere to be found, and pywallet says it requires "bsddb" when I run it, which is also nowhere to be found. I generated some vanity ...
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How can I export the private key for an address from the satoshi client?
If I want to transfer an address from the satoshi client into a different client, how can I find its private key to do so?
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Where is the data folder for Bitcoin-Qt?
Where can I find the blockchain, wallet.dat, etc. on each of the operating systems Bitcoin-Qt supports?
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When should I use -reindex-chainstate and when -reindex
What is the difference between the options -reindex and -reindex-chainstate?
Is one of the options faster?
When should each option be used?
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How can I restore my wallet?
I just purchased a new laptop and I want to decommission my old one. I have a back-up of my wallet.dat file copied to my new PC. What do I need to do to restore it to my Bitcoin (Windows) client? ...
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How exactly does -rescan work?
-rescan is a command line argument that is passed to the bitcoin client after restoring wallet.dat from backup.
Which files get recalculated?
Which files does the rescan command read?
Why is it a ...
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How can I combine all the tiny amounts I've received to minimise transaction fees, and do I need to?
Important parts in bold, for those who don't want to read the detail!
I've received lots of tiny transactions, in amounts sometimes as low as 0.000003BTC.
Even though I've also received (relatively) ...
- 10.9k
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Where can I access the original, Satoshi written Bitcoin code?
The articles of https://bitcointalk.org/index.php?topic=41718.0 seem to be annotated walkthroughs, and I'd like to see the raw code, as it was originally written in the first release.
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Why the signature is always 65 (1+32+32) bytes long?
A signature created by the Bitcoin-Qt client can always be decoded (base64) to a 65-byte array. This array seems (according to https://github.com/bitcoin/bitcoin/blob/master/src/key.cpp#L217) to ...
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Bitcoin URL scheme
What is the URL scheme that is used by Bitcoin to copy transaction information directly into the client? Which versions of Bitcoin clients support it?
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How to send bitcoin with a message attached
Is it possible to send bitcoins with an attached message with the transaction? If yes how to do it?
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Bitcoin-Qt command line control on Mac
I'm trying to communicate with the new Bitcoin-Qt -server via a command line on Mac. I run ./Bitcoin-Qt -server, the application starts, but my terminal window is stuck on an empty line (no matter ...
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Get non-wallet transactions using bitcoin rpc (gettransaction)
I am playing around with Bitcoin-qt. I want to iterate all blocks and all their transactions.
So far I've been able to get a list of all tx's in the blocks I want to. Now I want to get information ...
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How do I import private keys from Bitcoin-qt to Multibit client?
Question says it. I spent 20 mins Googling. Saw several links on bitcointalk.com but amazingly found no solution to this. Am I the first one trying to do this?
Note the following are not the ...
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Why was the MIT license chosen for Bitcoin?
Given that an open, transparent, distributed p2p network is a central element of Bitcoin project it seems unusual that it is licensed under the MIT license which allows proprietary closed source ...
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What's the difference between bitcoind and bitcoin-qt? Different commands?
This is a multi-part question, mainly do to contradictory information from different articles. It's got me all confused.
From my understanding, bitcoin-qt is just a GUI version of bitcoind - which ...
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Bitcoin-Qt setup: Change block-chain file location, settings? documentation?
I am installing Bitcoin-Qt and have been reading about Bitcoin basics, but I found very little information on the client. I have a few questions about the Bitcoin-Qt program (v0.8.1-beta under Windows ...
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Migration from Berkeley DB to LevelDB
In 2013 a new bitcoin core was released and one of the supposed improvement was migrating from Berkeley DB to LevelDB. According to the release notes at bitcoin.org:
LevelDB, a fast, open-source, ...
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How can I setup Bitcoin to be anonymous with Tor?
Bitcoin is billed as many things, among them its anonymity is highly regarded. While it is true that a transaction does not identify a user or wallet, recent news shows that there is the potential for ...
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How to decode private key from Android Bitcoin Wallet?
I want to import my private key from the android's Bitcoin Wallet (the one created by Andreas Schildbach) but it can export it only in an encrypted way.
How do I decrypt the file so I can import the ...
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What is the use case of bitcoind ZeroMQ?
What is the use case of ZeroMQ implementation for bitcoind which will be merged into Bitcoin Core v0.12.0?
Block and Transaction Broadcasting With ZeroMQ
https://github.com/bitcoin/bitcoin/blob/...
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Is bitcoin.org or bitcoincore.org the one to trust?
"Download Bitcoin Core": https://bitcoin.org/en/download
"Download Bitcoin Core": https://bitcoincore.org/en/download/
I've been alternating between the two sites for years. I have ...
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How to use the "Bootstrap.dat" file with bitcoin-qt?
I have searched around, and nothing I find works for me.
Downloaded the approx. 10 GB Bootstrap.dat file. Now stuck on trying to link it with Bitcoin-QT.
Tried the following command in the console ...
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Sync with bitcoin-qt very slow (0,01%)
I have the issue that my node's synchronisation is very slow. I am 14 weeks behind and it estimates to take 12 weeks to get synced. The synchronisation rate per hour is only 0,01%.
I have a fast ...
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How can I limit bandwidth usage in Bitcoin-qt client?
I've just finished the intial blockchain download/verify in my BitcoinQt client (17 hours..) and I now see that BitcoinQt is happily eating all of my upstream bandwidth. (About 110kByte/sec on my ADSL ...
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Are there Bitcoin password crackers I can use to recover forgotten passwords?
I've lost the password to one of my wallets (it's a small one, don't worry). I was sure I remembered the password ... but evidently I don't.
Is there a program that I can use to brute-force my ...
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Is there a reason to why Bitcoin Core does not implement BIP39?
Is there a specific reason to why BIP39 isn't added to Bitcoin Core? Seems very trivial to add and am confused to why it isn't there.
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What are the safety guidelines for using the Sign Message feature?
bitcoin-qt's dialog box states, "Be careful not to sign anything vague, as phishing attacks may try to trick you into signing your identity over to them. Only sign fully-detailed statements you agree ...
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getrawtransaction error? [Code -5]
I'm trying to read raw transactions but there is a problem; Seems like getrawtransaction only works for recent transactions, old transactions give me the next error:
No information available about ...
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Warning: Unknown block versions being mined! It's possible unknown rules are in effect
Recently, my full node (Bitcoin Core 0.14.2) displays this for both HD and non-HD wallets:
Warning: Unknown block versions being mined! It's possible unknown rules are in effect
What does this ...
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How does the Bitcoin client encrypt the wallet.dat file?
What is the algorithm used for encrypting the wallet.dat file?
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Should I be running Bitcoin Core or Bitcoin-XT?
I just read about Bitcoin Core and Bitcoin-XT, and I want to know what is the difference between Bitcoin Core and Bitcoin-XT?
And which is better Bitcoin Core or Bitcoin-XT?
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How do I specify in which directory Bitcoin blocks and other data should be stored? [duplicate]
I am on Windows and installed the Bitcoin wallet. The block folder seems to grow bigger everyday and is stored on my C drive in the roaming directory. I would like to set this to some other folder on ...
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How to run bitcoind in a low memory environment
I have a Raspberry Pi with 925 MB of memory. Bitcoin Core, operating as a full node, uses between 600-900 MB. How can I reduce bitcoind's memory usage?
I tried setting maxmempool to its minimum ...
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How can I transfer a Bitcoin-qt wallet to Electrum?
I am switching from bitcoin-qt to Electrum, and it seems as if I will need to download the blockchain again. Can I copy and paste my wallet.dat into Electrum's files?
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A complete bitcoin implementation in Python?
I recently became aware that python-bitcoinlib is not a full bitcoin node implementation, but rather a set of tools to work with bitcoin-core cpp. I would like to know whether there are some ...
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Where in Bitcoin Core does it do X?
Note that this is a general question and answer designed to serve as a guide for finding things in Bitcoin Core.
Where in Bitcoin Core's source code does it do X? How can I find that code by myself?
...
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What happens if the developers make a controversial change to the "standard" client?
One criticism I commonly hear of Bitcoin is that it merely transfers trust from some sort of central bank or government entity to the developers of the main project. Can anyone provide a clean ...
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How does "Sign Message" work?
How does "Sign Message" option in the Bitcoin QT client work? I can't find any description or documentation of it.
Do I have to use this option to sign some message when I receive bitcoins? If so, ...
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Attacking Bitcoin with a supercomputer
The difficulty in Bitcoin is recalculated every 14 days. What if immediately after this difficulty adjustment someone targets Bitcoin nodes with a supercomputer and start creating new blocks?
Such ...
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Can Bitcoin-Qt be configured to trim the blockchain?
I run Bitcoin-Qt and Bitcoin Armory on a laptop. I don't have the space to store the whole 20 GB (or however big it is now) blockchain.
I understand the need to run through the entire thing for ...
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How can I create a new wallet on Bitcoin Core?
How can I create a new wallet on Bitcoin Core (Bitcoin QT)? I forgot my old password, so I can't create transactions using the old wallet. I don't have money on my old wallet, I just need to create ...
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Why does the age of the coin in my wallet matter?
When a new transaction is made, the client seems to prefer older coins in the wallet.
What is the rationale for this? Are there any cases where it doesn't make sense to strictly collect coins by ...
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How to generate SegWit address
How do I generate a SegWit address using Bitcoin Core CLI? Also will I be able to redeem those outputs and send them to a "legacy" address? If so, will this second transaction be accepted by older, ...
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Estate planning: how can I ensure my bitcoins are inheritable?
What are good ways to ensure my bitcoins can be inherited by my family
when I die or become permanently incapacitated?
I think there are probably two significantly different situations to
account for,...
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bitcoin-cli not found on OSX
I have a Qt testnet3 node synched and running on my mac. In the terminal, when simply trying:
$ bitcoin-cli getinfo
or
$ ./bitcoin-cli getinfo
I get:
-bash: bitcoin-cli: command not found
...
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Why doesn't the Bitcoin core team develop official Bitcoin mining software?
If I am right, the Bitcoin Core just maintains the software necessary to run a full node. Essentially it's the code for the Bitcoin wallet, which just verifies blocks, but doesn't mine. But mining is ...
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opening an old wallet.dat
I had about $8 USD worth of bitcoin in a wallet, and I backed up the wallet.dat to my dropbox. According to the modified date of the file this was in April 2013, so it was probaby from bitcoin qt ...
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