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10

A while ago I created an extension for BitcoinLib in order to put bitcoind to the test. The setup was trivial: call getnewaddress() in the main network for ever My performance index was the number of addresses generated per second. It took off on an average of 35 addresses/sec. I left it running on a VM for a whole month. The rounded results were: Total ...


10

You don't want to be storing any funded keys server side, there's an almost constant steam of hosts being compromised to steal funds. Most Bitcoin systems use something called a "hot wallet", and move the rest onto individual paper wallets outside of the servers control. It's then the administrators role to move funds back and forth to keep the hot wallet ...


8

The easiest way to do this is to have the QR code be a URL. For example, http://www.example.com/bitcoingiveaway/E34IKJ. Just assign a unique code to each location, the E34IKJ in my example. What that web page does is up to you. It has to track how many times it has been accessed, of course. The first time, it can send a form that allows a person to fill in ...


7

Actually, most transactions you see will have two recipient addresses. One is for the actual transaction and the other one is change. When the output of a transaction is used as the input of another transaction, it must be spent in its entirety. Sometimes the coin value of the output is higher than what the user wishes to pay. In this case, the ...


6

Yes, all of those are stored in the wallet.dat file. I myself have successfully migrated the wallet file to a new computer and have the addresses and descriptions intact.


5

You should check the following: Are you sure you entered the right address to receive the Bitcoins? If the address is not correct, the coins are lost Did your Bitcoin client download all the blocks in the chain? (>150000) If not, you need to let it run for awhile, until it downloads all the blocks, making sure that you have a couple connections and the ...


5

The coin selection that the client does is performed behind the scenes, the client takes care of the details. But if you are curious to know what happens behind the scenes: INPUT: Address: A 1.0 BTC Address: B 1.0 BTC OUTPUT: Address: C 2.0 BTC FEE (derived as inputs - outputs): 0.0 BTC This is assuming you didn't pay a fee. Let's say instead you ...


4

You send them a bitcoin address along with the invoice. Use a different address each time, so that you can tell who paid you.


4

There are no rules. Once you share an address with someone, they can send arbitrary amounts of bitcoin to that address. They can also send further transactions to that address any time in the future. There is no way to reject a transaction just because you don't like the amount or for any other reason; if the transaction spends valid coins and is ...


4

Think of Bitcoin like a ledger. When you (your Bitcoin wallet) receives Bitcoin, instead of receiving an item or file, everyone is updated with an updated ledger including the balance of your Bitcoin address. Here is an extraordinary explanation on Bitcoin.


4

Blockchain Explorer says received but it's not received yet! That's not how Bitcoin works. All computer-based wallets, including your friend's, have a copy of the blockchain (or have indirect access to a copy). If the blockchain includes your transaction, then the money has been received. All copies of the blockchain are eventually identical, only the last ...


3

There's absolutely nothing you need to do per address, so the number of addresses has no effect. You only need to process each transaction.


3

Nope. Or, at least, unless you are law enforcement and have a subpoena. Or, unless you redeemed it yourself (which would list in your deposit history). You can tell if it has been redeemed by redeeming it yourself and seeing if it had funds, but that's about it.


3

A Bitcoin transaction can have multiple inputs (and multiple outputs). In the scenario you described, a single transaction will be created, which will include as inputs both the payment to A and the payment to B. Usually, the receiving party will not care what are the inputs of a transaction, he will care that the output will include the expected payment to ...


3

According to the Blockexplorer, you should see all of those transactions when you reach block 163971. Your client probably needs to finish synchronising with the network, as the first transaction is the newest one. If you see the second transaction, then you still have about 7 days at most to synchronise. Just leave your client on for a couple hours and you ...


3

Intersango has been having a problem with their wallet recently, as described in this forum post. Another post claims that: this was triggered by someone spamming the wallet with a very larger number of small transactions Encrypting your wallet won't make any difference to whether you receive the bitcoins or not. You only need to "unlock" the wallet ...


3

Using the default client (which it appears you are) transactions received while the client is online will usually appear immediately but transactions which occur while the client is offline will not appear until the block containing them is downloaded. Based on your description this appears to be what has happened, so your transaction should show up whenever ...


3

Solution This works fine. The bitcoins will appear next time I start my wallet application. (Read tuxcanfly answer) Bitcoins are not actually received by the software (wallet) on my computer, they are appended to a public ledger that is shared between all the devices on the Bitcoin network. (Read SPRBRN comment) If someone sent bitcoins when my wallet ...


3

Click "Receive" tab >>> Click "Request payment" button Note: "Label", "Amount" and "Message" fields are optional View Receiving Addresses: "File" >>> "Receiving addresses..."


3

In Bitcoin Core, the sending address refers to the address that you have saved as a "contact" in the client. You can save the address with a nickname eg. Coinbase address. The receiving address refers to the address which you can use to receive coins. The way Bitcoin works is that a transaction spends the unspent output from the receiving addresses. Hence, ...


3

Are the transactions added to the genesis block spendable, just like any other transactions from other blocks, or is that an unspendable coinbase transaction. Transactions aren't spendable; transaction outputs are. Is the transaction within the Genesis block spendable, provided the corresponding private key of the bitcoin recipient is found? The single ...


2

Addresses can both be used both for sending and receiving transactions. However, some online wallet services share addresses between different users, so you want to be careful if you are using one of those. Use a "receive payment function" or "my address", or whatever it might be called, to get the address that can receive payments for you. If you are using ...


2

If you dont want to use ANY 3rd party service, you will need to parse the entire blobkchain and put it inside a database so you can query whatever information you want. To do that you have two options: code your own parser for blocks/transactions, and here i suggest you using the rcpapi (its all json, nothing crazy) instead of doing it the hard way like ...


2

But to answer the question: addresses do NOT expire. Not in Multibit, not in cold storage, not online (unless the site retired and you do not have an offline private key or wallet), nor any other wallet software. They can be used unlimited amount of times, so that's not the problem either. The problem your face is probably in Multibit. You can try to backup ...


2

An individual or merchant requesting payment will generally want to obtain a bitcoin address specific for that transaction. When done manually, this is obtained from the Bitcoin-Qt client by clicking "Receive". A merchant would have software that would query the Bitcoin.org client to obtain the address. An EWallet provider will provide for you this address....


2

This is entirely possible with an optional additon to Bitcoin called BIP32. Unfortunately, BIP32 is not implemented by the standard client, but there are other clients that do implement it. Ask your customer to download the latest version of Electrum, then have them give you their extended public key. (As I said above, there are multiple clients that can ...


2

Why not just use Electrum instead? It's easy enough to integrate with an Electrum wallet, and it has a customisable lookup gap that can be as big as you need it to be.


2

Bitcoin Core stores your keying material in a single wallet but, at least in Linux, it is possible to tell the application to use a different wallet with the -wallet flag: -wallet=<file> Specify wallet file (within data directory) (default: wallet.dat) From the command line: $ bitcoin-qt -wallet=anotherwallet.dat. This creates a wallet with ...


2

The network contains those transactions (either in nodes' mempool or block) and you will receive your Bitcoins when you are back online.


2

When the wallet initializes, it will generate a master private key for the you as part of the initialization. All subsequently generated keypairs will be related to the master private key, this is called a 'Hierarchical Deterministic' Wallet (HD wallet). An HD wallet is nice, because you only need to backup the seed phrase that generates your master ...


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