How do I figure updating which file you need which one bitcoin block not At any given point in time, the probability that no transactions will be confirmed in the next hour is about 0. I'm seeing this on a postgres count. If your transaction confirms and the merchant does not fulfill your order, you don't need to reach block to BitPay. Is bcfb from your fork still needed? Mining is the process of spending computation power to secure Bitcoin transactions against reversal and introducing new Bitcoins to the system .
The difficulty of the mathematical problem is automatically adjusted by the network, such that it targets a goal of solving an average of 6 blocks per hour. The appropriate fee varies depending on how large in bytes your transaction is, how fast you want the transaction to be confirmed, and also on current network conditions. A ponzi scheme is a zero sum game. Oftentimes wallets will have an "express" fee configuration, but note that confirmation times are naturally random and unreliable. Have a question about this project? Of course it is possible to check for specific error codes instead and do things for specific error codes
All unconfirmed transactions compete with each other to be picked up by miners. New blocks cannot be submitted to the network without the count answer - the process of " mining " is essentially not process of competing to be the next to find the answer that bitcoin the current block. With an initial block reward of 50 Count, it will updating many 4-year periods bitcoin the block reward to reach zero. The latest version of the Bitcoin-Qt client tells you how far it has block to go in downloading the blockchain. Bitcoin doesn't ask that its users trust any institution. This feature is then used in the Bitcoin network to allow the block to come to a consensus on the history of transactions. Updating that not unlikely to happen:
If confidence in Bitcoins is lost then it will not matter that the supply can no longer be increased, the demand will fall off with all holders trying to get rid of their coins. An example of this can be seen in cases of state currencies, in cases when the state in question dissolves and so no new supply of the currency is available the central authority managing the supply is gone , however the demand for the currency falls sharply because confidence in its purchasing power disappears.
Of-course Bitcoins do not have such central authority managing the supply of the coins, but it does not prevent confidence from eroding due to other situations that are not necessarily predictable. Yes, in the same way as the euro and dollar are. They only have value in exchange and have no inherent value. If everyone suddenly stopped accepting your dollars, euros or bitcoins, the "bubble" would burst and their value would drop to zero.
But that is unlikely to happen: Bitcoin does not make such a guarantee. There is no central entity, just individuals building an economy. A ponzi scheme is a zero sum game. Early adopters can only profit at the expense of late adopters. Bitcoin has possible win-win outcomes. Early adopters profit from the rise in value.
Late adopters, and indeed, society as a whole, benefit from the usefulness of a stable, fast, inexpensive, and widely accepted p2p currency. The fact that early adopters benefit more doesn't alone make anything a Ponzi scheme.
All good investments in successful companies have this quality. Early adopters in Bitcoin are taking a risk and invested resources in an unproven technology. By so doing, they help Bitcoin become what it is now and what it will be in the future hopefully, a ubiquitous decentralized digital currency.
It is only fair they will reap the benefits of their successful investment. In any case, any bitcoin generated will probably change hands dozens of time as a medium of exchange, so the profit made from the initial distribution will be insignificant compared to the total commerce enabled by Bitcoin.
Worries about Bitcoin being destroyed by deflation are not entirely unfounded. Unlike most currencies, which experience inflation as their founding institutions create more and more units, Bitcoin will likely experience gradual deflation with the passage of time. Bitcoin is unique in that only a small amount of units will ever be produced twenty-one million to be exact , this number has been known since the project's inception, and the units are created at a predictable rate.
Also, Bitcoin users are faced with a danger that doesn't threaten users of any other currency: And not just to him; it's gone completely out of circulation, rendered utterly inaccessible to anyone. As people will lose their wallets, the total number of Bitcoins will slowly decrease. Therefore, Bitcoin seems to be faced with a unique problem. Whereas most currencies inflate over time, Bitcoin will mostly likely do just the opposite. Time will see the irretrievable loss of an ever-increasing number of Bitcoins.
An already small number will be permanently whittled down further and further. And as there become fewer and fewer Bitcoins, the laws of supply and demand suggest that their value will probably continually rise. Thus Bitcoin is bound to once again stray into mysterious territory, because no one exactly knows what happens to a currency that grows continually more valuable. Many economists claim that a low level of inflation is a good thing for a currency, but nobody is quite sure about what might happens to one that continually deflates.
Although deflation could hardly be called a rare phenomenon, steady, constant deflation is unheard of. There may be a lot of speculation, but no one has any hard data to back up their claims. That being said, there is a mechanism in place to combat the obvious consequences. Extreme deflation would render most currencies highly impractical: Even pennies would fetch more than a person could carry.
Bitcoin, however, offers a simple and stylish solution: Bitcoins can be divided up and trade into as small of pieces as one wants, so no matter how valuable Bitcoins become, one can trade them in practical quantities. In fact, infinite divisibility should allow Bitcoins to function in cases of extreme wallet loss. Even if, in the far future, so many people have lost their wallets that only a single Bitcoin, or a fraction of one, remains, Bitcoin should continue to function just fine.
No one can claim to be sure what is going to happen, but deflation may prove to present a smaller threat than many expect. For more information, see the Deflationary spiral page.
Bitcoin markets are competitive -- meaning the price of a bitcoin will rise or fall depending on supply and demand at certain price levels. Only a fraction of bitcoins issued to date are found on the exchange markets for sale. So even though technically, a buyer with lots of money could buy all the bitcoins offered for sale, unless those holding the rest of the bitcoins offer them for sale as well, even the wealthiest, most determined buyer can't get at them.
Additionally, new currency continues to be issued daily and will continue to do so for decades; though over time the rate at which they are issued declines to insignificant levels. Those who are mining aren't obligated to sell their bitcoins so not all bitcoins will make it to the markets even. This situation doesn't suggest, however, that the markets aren't vulnerable to price manipulation.
It doesn't take significant amounts of money to move the market price up or down, and thus Bitcoin remains a volatile asset. That the block chain cannot be easily forked represents one of the central security mechanisms of Bitcoin.
Given the choice between two block chains, a Bitcoin miner always chooses the longer one - that is to say, the one with the more complex hash. Thusly, it ensures that each user can only spend their bitcoins once, and that no user gets ripped off. As a consequence of the block chain structure, there may at any time be many different sub-branches, and the possibility always exists of a transaction being over-written by the longest branch, if it has been recorded in a shorter one.
The older a transaction is though, the lower its chances of being over-written, and the higher of becoming permanent. Although the block chain prevents one from spending more Bitcoins than one has, it means that transactions can be accidentally nullified. A new block chain would leave the network vulnerable to double-spend attacks.
However, the creation of a viable new chain presents considerable difficulty, and the possibility does not present much of a risk. Bitcoin will always choose the longer Block Chain and determines the relative length of two branches by the complexities of their hashes.
Since the hash of each new block is made from that of the block preceding it, to create a block with a more complex hash, one must be prepared to do more computation than has been done by the entire Bitcoin network from the fork point up to the newest of the blocks one is trying to supersede.
Needless to say, such an undertaking would require a very large amount of processing power and since Bitcoin is continually growing and expanding, it will likely only require more with the passage of time.
A much more distinct and real threat to the Bitcoin use is the development of other, superior virtual currencies, which could supplant Bitcoin and render it obsolete and valueless.
A great deal of careful thought and ingenuity has gone into the development of Bitcoin, but it is the first of its breed, a prototype, and vulnerable to more highly-evolved competitors. At present, any threatening rivals have yet to rear their heads; Bitcoin remains the first and foremost private virtual currency, but we can offer no guarantees that it will retain that position. It would certainly be in keeping with internet history for a similar system built from the same principles to supersede and cast Bitcoin into obsolescence, after time had revealed its major shortcomings.
Friendster and Myspace suffered similar fates at the hand of Facebook, Napster was ousted by Limeware, Bearshare and torrent applications, and Skype has all but crushed the last few disciples of the Microsoft Messenger army. This may sound rather foreboding, so bear in mind that the introduction of new and possibly better virtual currencies will not necessarily herald Bitcoin's demise.
If Bitcoin establishes itself sufficiently firmly before the inception of the next generation of private, online currencies so as to gain widespread acceptance and general stability, future currencies may pose little threat even if they can claim superior design.
This is known as the network effect. Is this a problem? This is only a problem if you are investing in Bitcoin for short period of time. A manipulator can't change the fundamentals, and over a period of years, the fundamentals will win over any short term manipulations. It can be significantly more or less time than that depending on luck; 10 minutes is simply the average case.
Blocks shown as " confirmations " in the GUI are how the Bitcoin achieves consensus on who owns what. Once a block is found everyone agrees that you now own those coins, so you can spend them again. Until then it's possible that some network nodes believe otherwise, if somebody is attempting to defraud the system by reversing a transaction.
The more confirmations a transaction has, the less risk there is of a reversal. Only 6 blocks or 1 hour is enough to make reversal computationally impractical. This is dramatically better than credit cards which can see chargebacks occur up to three months after the original transaction!
Ten minutes was specifically chosen by Satoshi as a tradeoff between first confirmation time and the amount of work wasted due to chain splits. After a block is mined, it takes time for other miners to find out about it, and until then they are actually competing against the new block instead of adding to it. If someone mines another new block based on the old block chain, the network can only accept one of the two, and all the work that went into the other block gets wasted.
Lengthening the time between blocks reduces this waste. As a thought experiment, what if the Bitcoin network grew to include Mars? From the farthest points in their orbits, it takes about 20 minutes for a signal to travel from Earth to Mars. With only 10 minutes between new blocks, miners on Mars would always be 2 blocks behind the miners on Earth.
It would be almost impossible for them to contribute to the block chain. If we wanted collaborate with those kinds of delays, we would need at least a few hours between new blocks. YES, you do, IF the transaction is non-recourse. The Bitcoin reference software does not display transactions as confirmed until six blocks have passed confirmations.
As transactions are buried in the chain they become increasingly non-reversible but are very reversible before the first confirmation. Two to six confirmations are recommended for non-recourse situations depending on the value of the transactions involved. When people ask this question they are usually thinking about applications like supermarkets. This generally is a recourse situation: Double-spends might be a concern for something like a snack machine in a low-traffic area with no nearby security cameras.
Such a machine shouldn't honor zero-confirmation payments, and should instead use some other mechanism of clearing Bitcoin or validating transactions against reversal, see the wiki article here for alternatives.
Applications that require immediate payment processing, like supermarkets or snack machines, need to manage the risks. Here is one way to reverse an unconfirmed payment:.
A Finney attack is where an attacker mines a block containing a movement of some coins back to themselves. Once they find a block solution, they quickly go to a merchant and make a purchase, then broadcast the block, thus taking back the coins.
This attack is a risk primarily for goods that are dispatched immediately, like song downloads or currency trades. Because the attacker can't choose the time of the attack, it isn't a risk for merchants such as supermarkets where you can't choose exactly when to pay due to queues, etc. The attack can fail if somebody else finds a block containing the purchasing transaction before you release your own block, therefore, merchants can reduce but not eliminate the risk by making purchasers wait some length of time that's less than a confirm.
Because pulling off this attack is not trivial, merchants who need to sell things automatically and instantly are most likely to adjust the price to include the cost of reversal fraud, or elect to use special insurance.
So after having an IP or two banned because of checking to often First don't use the script under this update; the variable expansion Bash preforms causes multiple calls to https: You can try adding sleep between the assignment and calls but that would be very slow. The last one above is likely the best for scripting as the file it saves to can be read for just the number inside or the last time it was modifide. The person to show the correct function was LoHoris, however, the updates to Bitcoin node software now uses bitcoin-cli getblocktemplate and not bitcoind for these lookups.
Thanks to both of them it is possible to offer you all a combination of both answers wrapped into a checker script; ready for your customization and updated for the year This script first checks the exit status of bitcoin-cli getblocktemplate because anything other than 0 is usually an error it'll run the other parts only if bitcoin-cli getblocktemplate shows an error.
Of course it is possible to check for specific error codes instead and do things for specific error codes The other checks then compare local block count verses https: These only run when local check of sync status error out thus if you're on a slower like Steven Roose mentioned then this script is ideal.
And add one line to crontab to accomplish running on a schedule. Last modify the very end of the script to write output to a file. Hopefully this is acceptable enough of an answer to mark this question as [Solved] such that future web searchers can have an easier time of this.
Bitcoin Stack Exchange is a question and answer site for Bitcoin crypto-currency enthusiasts. Join them; it only takes a minute: Here's how it works: Anybody can ask a question Anybody can answer The best answers are voted up and rise to the top. How to check if the block chain is up to date using bitcoind or json-rpc?
Steven Roose 8, 7 27 BinaryMage That question does not make clear that it is about the daemon in the headline. I would have ignored it if I had seen it when I was looking for an answer. Check out my edit. The getwork call will fail if you aren't up to date. As others have said, there is no absolute way of telling if your blockchain is up to date. With the high volume of questions we're getting about delayed payments, we decided it would be best to write a short explanation about what's happening with many bitcoin transactions right now.
Transactions on the Bitcoin network itself aren't controlled or confirmed by BitPay, but by the bitcoin miners which group transactions into "blocks" and add those blocks to the Bitcoin "blockchain" — the shared historical record of all transactions. When a transaction has been added to a block six blocks ago, it's considered a done deal. Currently, bitcoin network traffic is unusually high due to increasing demand for transactions per block.
Block sizes are limited, so this means that transactions which exceed the capacity for a block get stuck in a queue for confirmation by bitcoin miners. This queue of unconfirmed transactions is called the bitcoin mempool. For context on what's happening now, here is a look at the current bitcoin mempool size. A lot of people are interested in using bitcoin for transactions.
The bad news is that this network traffic may produce delays of a few hours to a few days for some users and a wait time of weeks for a small number of users. If your bitcoin transaction to a BitPay merchant has not confirmed yet, you will need to wait for it to be confirmed by bitcoin miners. Since BitPay does not control confirmation times, there is unfortunately nothing we can do to speed up the process once your transaction has already been broadcast to the network.
You can check your transaction's confirmation status and other payment details on any blockchain explorer like BitPay's block explorer Insight. Look up your transaction using your transaction ID or the sending or receiving bitcoin addresses, which can all be found in your bitcoin wallet that sent the payment.
Bitcoin Block Explorer is a web tool that provides detailed information about Bitcoin blocks, addresses, and transactions. Home. Summary, Status: Disconnected. Total Fees, BTC. Total Size, (KB). Transactions Per Second, fc95eadc8d62cae10dbeabfba14df0cd94faa1 1H4b2NgLGXL7MyEHg5T4Dx9wPn5hbkVCjZ. Http().request("wearebeachhouse.com") except Exception as e: print "Unable to get true blockcount from blockexplorer:"+str(e) else: if Slightly abstractly, and probably not useful in your case, the client is always syncing: there is no real difference between "having all blocks" and "not.