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9

Obviously, he is a scammer trying hard to look similar as the Blockchain's Official Investment scheme but there isn't anything like this ever before. Many scammers are there, one of the most luring advert is 'Earn through Bitcoin Mining from Antminer(S9)'. In the name of Antminer(S9) many persons reaching out through various social platforms to you and ...


6

The vast majority of the time, none of the 2^32 possible nonces in a particular block header template will result in the header having a hash that meets the proof-of-work target. In fact, the probability that this doesn't happen equals exactly 1 over the network difficulty. Right now, that is 1/6,379,265,451,411. When no nonce succeeds, one must change ...


5

A transaction could go unconfirmed indefinitely. The order in which transactions are confirmed is decided by miners, and generally they will be incentivized to include only the highest fee-rate transactions, to maximize their revenue. Even a low fee-rate transaction may eventually confirm, once the mempool clears out. But there is no guarantee of this, ...


5

All of the transaction history is communicated between peers over a binary gossip protocol. You can request specific blocks, sequences of blocks, or specific transactions, and clients will normally communicate by broadcasting all of the information they receive to other peers they are connected to - enabling each client to stay mostly up-to-date once they've ...


5

someone on blockchain support ask me to tell him my back up fund 12 word in order to reverse my bitcoin which was unconfirmed in my transaction Sorry to say, you were definitely scammed. You cannot reverse a bitcoin transaction in that way, the scammer only told you that so that you would give them the 12 word phrase. With that phrase, the scammer could ...


3

How can they list the unspent transactions and the current amount of an address which "is not in their wallet"? Block explorer sites maintain a separate database of information which is built by continuously scanning the Bitcoin blockchain. If block explorer sites see a standard locking script in the outputs of the transactions, they scrape the addresses ...


3

Blockchain.com is not a blockchain node, it is an explorer. They have no constraint on following the same rules as a Bitcoin Core node, and can keep orphaned and forked blocks available if they wish to, and return all blocks they know of for a block height if they wish to. In the main Bitcoin chain, things are as you say - Only a single block may survive at ...


3

It is difficult to cancel a Bitcoin transaction after it's been sent, and it cannot be done by the recipient, only by the sender. If the transaction has been confirmed, cancellation becomes impossible. However, the funds are not lost. They will be waiting in the address until you claim them. You can either eventually finish installing and syncing Bitcoin ...


2

This doesn't sound correct to me. You're relying on a centralized service to fetch blocks. What if their system has an error and sends you incorrect data? What if their service is unreachable? It doesn't seem like you have any way to handle blockchain reorganization. You might end up crediting a payment twice, or crediting where a double spend was ...


2

In addition to Chytrik's mention of a dust attack, dust limit transactions are also used heavily by the Omni Layer to identify the recipient of an omni asset. Transactions such as those will follow pattern of one dust (or near dust) output, an OP_RETURN output, and a change output. While dust attacks tend to create thousands of dust outputs in a handful of ...


2

This output value corresponds to the dust limit that is imposed on bitcoin transactions. Many of these outputs may have been generated as a dust attack to de-anonymize users/ addresses.


2

Blockchain.info (and other block explorers) do additional processing of the transaction data in order to make it more user friendly to follow the path of coin movement through multiple transactions. Additionally, it seems that whatever you are using to print out the transaction details is not showing you all of the information. In a transaction, each input ...


2

Your transaction size calculation is incorrect. The inputs are 1 byte input count + 36 byte output + 1 byte scriptSig + 4 byte sequence + 1 byte witness stack count + 1 byte signature length + 71 byte signature + 1 byte pubkey length + 33 byte pubkey = 149 bytes for all of the input data. That along with 32 bytes for output, and 10 bytes for the rest of the ...


2

gettransaction is a wallet RPC. It only works for transactions your wallet knows about. Presumably this is not the case for a transaction from 2013. getrawtransaction is a node RPC. It works for all transactions, but needs help to find them. One possibility is to enable the transaction index (put txindex=1 in bitcoin.conf, or -txindex on the bitcoind ...


2

In the bitcoin blockchain, the difficulty of mining is adjusted after every 2016 blocks. If the average mining time for the last 2016 blocks was higher than 10 minutes than the difficulty is reduced so that the time readjusts to 10 minutes. While if the time to mine the last 2016 blocks was lower than 10 minutes, then the difficulty is increased. Although ...


1

If you lack free space enable disk space restrictions via settings menu > options > main tab. You will still need to download the blockchain but it'll automatically delete blocks that it has verified to lower disk space usage. The lowest you can set the amount there is 550 megabytes. However if you do that it'll use about 3.5GB so that's the minimum amount ...


1

By design, it is not possible to determine the private key for arbitrary addresses. If you do not have a wallet file, seed phrase, or other form of keys that lead to that address, no one can help you. If someone asked you to transfer Bitcoin to a watch only address claiming it will be accessible by you, you have been scammed.


1

No, they would not. In Bitcoin, wallet is an abstract concept as it is just a software that manages your private keys and addresses. The addresses generated from the private key in your wallet bear no resemblance to others. Unless you explicitly mention it to them that it is your address, there is no way of knowing whether it is you who has sent the bitcoins ...


1

To request an individual block from a p2p peer, consider the get_data message, indicating what type of block (witness/compact/filtered). Since you do not wish to do full block download and validation, you can first build a header chain to the most recent height, and then verify the block you are requesting is in the header chain. This would ensure that it ...


1

Blockchain.info does appear to support testnet blocks and transactions by simply using the "testnet" subdomain. For example: txid: 4200cea53a075f3081156a9d664fe05cfe108a09e26e8f20ee65e7ebe141060b block: 1443900 address: mum6KQEwAHGDRr7HRXx7hufcsyqiGPUCtN So in your case simply use this: https://testnet.blockchain.info/tx/#{txid} https://testnet....


1

The Bitcoin system doesn't have a "sender's address". You can walk the transaction history to find out what destination the coins you were paid was last sent to but that is not a "sender's address". Imagine if you had a magic wand you could wave over any package you received in the mail that would tell you where it was last mailed before you. You wave the ...


1

There is a free bitcoin-cli sandbox at bitcoindev.network: Here is a simple sandbox environment for trying out the bitcoin command line interface! Select Start Scenario to bootstrap your own private instance! You can check out the on-line sandbox here: https://bitcoindev.network/bitcoin-cli-sandbox/ Simultaneously they provide a docker container for ...


1

Zapier is a great tool that you can use to accomplish actions like mail download links, send SMS, push notification to slack etc. You can setup bitcoin payment as trigger and then configure action to do.


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