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I need to get some values to find how updated my bitcoind client is.
For example, I would like the GUI to tell me:
Are there commands available in the JSON API to get this information? Or how else can I achieve this?
Regards
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You probably need to read: https://en.bitcoin.it/wiki/Original_Bitcoin_client/API_calls_list
You'll probably like the methods getblockcount and getblocknumber.
I don't think the API can give you the latest blocknumber until it's been updated, but you can find it on http://bitcoinwatch.com/ -> blocks -> count.
more details ( from #bitcoin-dev on IRC, thanks to sturles ) : the client can't know for sure until all the blocks are verified, but it can report what other clients claim they have. A malicious client can report arbitrary numbers to your client, so the bitcoin client can not be sure until the last block is verified. It can also make a guesstimate based on the current time and the age of the last verified block. – neofutur – 2012-03-09T11:45:17.947
so your best guess will probably be to get the latest block number from a trusted provider ( bitcoinwatch.com is just an example) – neofutur – 2012-03-09T11:47:19.737
Thanks for your reply.
I read that API command list but it is pretty vague.
The whole idea of doing this was to avoid using any 3rd party :(
How can I make a guestimate? How can I get the last verified block?
Cheers. – lbo – 2012-03-09T11:51:35.320
you have no way to be sure of it until your local client have verifieds all the blocks; other clients can lie to you, but having a look at the client code and debug.log, you could find that other nodes are sending you messages like "version message: version 32300,blocks=170346", they tell you their version and blockcount, you can ignore old version clients and decide that all the latest version ones should have the latest block. – neofutur – 2012-03-09T12:26:19.110
2 having this option ( downloaded XXX/YYYY blocks ) could really be useful for bitcoin users, if you can implement it as an API call, please fork https://github.com/bitcoin/bitcoin and send a pull request to share your good idea with others !
I was under the impression that version 5+ of the client (bitcoin-qt) offers all these capabilities. Am I wrong? – ripper234 – 2012-03-09T12:37:42.907
The client can't possibly tell if it's up to date in terms of blocks. The only way the client can know a block exists is to validate it. The only way to validate a block is to have it already. The client has no other mechanism to become convinced that it's not already current. (The exception would be if there was a checkpoint ahead of it.) – David Schwartz – 2012-03-10T05:44:27.663
How does Bitcoin-QR know it is "out of sync"? And it also says something like ~24 block(s) remaining. – kermit – 2012-10-28T14:39:26.763