Transcript for #bitcoin-dev 2017/03/06

00:51 ruid I want to play around on the testnet. How do I create a wallet, and get receive addresses? listreceivedbyaddress is empty.
02:04 praxeology ruid you still there?
07:54 bit7_ can some kind soul please help me with the NBitcoin C# Library ? I am having some issues with Sending of Bitcoins to a TestNet Test Wallet. Thank You. :)
08:12 bit7_ any kind soul can help me with coding a program in C# with the NBitcoin Library ? :)
08:41 fnb_theory bit7_ you still need help with NBitcoin?
08:51 bit7_ FnB_Theory - may i please kindly ask if you are still there sir ? :D
08:54 fnb_theory yeah I'm here bit7_, where are you getting stuck?
08:54 bit7_ validateaddress
08:55 bit7_ sorry to cut it short - i have went to the bitcoin stack exchange to ask on this issue
08:55 bit7_ may i please kindly ask your kind self to read the whole article at the bitcoin stack exchange ... sorry for the inconveniences :)
08:56 fnb_theory yeah, read it. I'll answer you on there. I think I still have an account lying somewhere
08:57 bit7_ Thank you very much for your time and kind help FnB_Theory ... I really appreciate it very much !!! :D
08:57 fnb_theory no problem.
09:19 bit7_ if you get the code to work, please post a reply on the forum and message me here so I will know to check out the forum for updates. Thank you
09:21 fnb_theory I've posted an answer.
09:35 bit7_ Dear Fnb_Theory - When i compiled the code using your Bitcoin Address Function, the Visual Studio Compiler gives an error message. Can you please take a look at the Stack Exchange Thread again ... Thank You for your help :)
09:41 fnb_theory check out my reply.
09:43 bit7_ Thank you FnB_Theory - I am compiling my code and will test it out now :)
09:52 bit7_ Dear FnB_Theory - I posted a reply on the Thread - It is not working for some reason ... can you please kindly take a look again and help out ... :)
10:13 bit7_ Dear FnB_Theory - may i please kindly ask how can i configure BitPay wallet to use the TestNet network ? Thank You.
10:48 fnb_theory Hi bit7_, if you create a new wallet in copay, there is an advanced section that you can expand during the create process. It'll ask you if you'd like to use testnet. Toggle that switch.
10:48 fnb_theory In order to get money into that wallet, you can use a bitcoin testnet faucet
10:50 bit7_ do i need bitcoin core to use bitpay ?
10:52 fnb_theory as in, running a bitcoin node?
10:52 bit7_ sorry - i meant if i want to use BitPay wallet software and send and receive bitcoins - do i need to use bitcoin core ?
10:53 bit7_ or can i simply just instll bitpay and send and receive bitcoins without any need for bitcoin core
10:53 fnb_theory yeah, you don't need to be running a Biicoin node. Copay/BitPay will connect to its own.
11:01 bit7_ Thank you very much for your kind help and time - I need to compile my code again ... FnB_Theory - Thank You !!! :)
11:02 fnb_theory No problem bit7_, let me know if you need any more help.
11:43 bit7_ FnB_Theory - somehow the bitpay testing is not working ... i use bitpay as a test wallet to receive bitcoins from my program and it is not coming in ... but if i send bitcoins from a testnet faucet it works ... it is almost as if there is something about the C# code in the program that is not working somewhere ... :(
11:44 bit7_ i have tested 2 wallets on testnet and it is not working too
11:44 bit7_ perhaps can you recommend a good c# bitcoin library that i can just use to write a simple bitcoin transaction program ? Thank You :D
11:48 fnb_theory I think what I can do is send you some working code. NBitcoin is the best C#, and only afaik, library out there right now.
11:48 bit7_ yes please thank you very much for the code ... how can you send the code to me ?
17:26 bit7_ can any kind souls please spare a few testnet bitcoins to my testnet wallet please?
17:27 shesek I made a time-locked-weighted (via CSV) voting system this past weekend for a hackathon, would love to hear what you think :)
17:27 shesek
17:27 shesek (running on testnet, hackathon-grade quality :-)
17:28 shesek source is available here:, including a cli tool to create the HODL proofs locally
17:31 bit7_ does any kind souls know of a web based test wallet which will give me a secret key?
17:32 bit7_ please also recommend a website that gives test bitcoin ? Thank you
17:41 molz_ bit7_, what's your testnet address?
17:41 molz_ bit7_, send me in pm
17:41 molz_ not sure if the bot might kick you if you post an address here
17:44 bit7_ how do I pm you?
17:45 molz_ type: /query molz_
18:48 praxeology Any plans to drop support of 32 bit builds?
18:49 praxeology Who still uses a 32 bit computer these days?
18:49 wumpus not in general
18:49 wumpus many small VPSes are still 32 bit, and ARM is mostly 32-bit too (although 64 bit is becoming more popular there too)
18:50 wumpus there was discussion of dropping the 32-bit windows build at some point, but there's no urgent motivation to do so.
18:51 praxeology if i use uint64_t, and fopen64, and do basic arithmetic on the uint64_t, would that cause any problem with a 32-bit build?
18:51 wumpus no
18:52 praxeology ok good
18:52 praxeology I guess its all define macro'd so it works seamlessly?
18:53 wumpus compilers are smart enough to do 64-bit arithmethic on 32-bit architectures
18:53 wumpus in additions it's just a matter of propagating the carry, for multiplications it's slightly more involved unless the CPU
18:53 wumpus has a 32x32->64 or 32x32->32hi instruction, as most do
18:54 wumpus in any case it's not something you need to worry about while writing C/C++
18:55 praxeology alright, because I'm trying to make utxo backup states in single files, and soon enough the utxo set will be > 2GB and I wanted to be sure it would still work on the 32 bit build :)
18:55 wumpus there are some filesystems that don't support >2GB or >4GB files, but it has nothing to do with the bitness of the processor
18:57 Diablo-D3 good ole signed ints.
18:59 praxeology1 uh, did I miss any reply? I was disconnected
19:18 praxeology wumpus was that you answering my questions about 32/64 bit? thanks. cheers.
23:37 ginseng what is the total approximate size of the full blockchain with pruning enabled?
23:38 praxeology ginseng: about prune leave count blocks * 1MB
23:39 praxeology plus the unspent transaction data is 2GB
23:39 praxeology but that is not technically the "blockhain", but it is necessary data
23:40 praxeology plus blockheadersize * tip height
23:41 praxeology plus the block index is about 70MB
23:41 ginseng praxeology: ok. are all 450k blocks prunable?
23:41 praxeology You can't prune to the tip because of concern for forks
23:42 ginseng how close to the tip can you prune?
23:43 praxeology but you could prune to only have say 6*24*30 blocks would be fine, thats 4.3GB, only double the unspent transaction data
23:43 praxeology 6*24*30 is 30 days, which is probably waaay more than a fork would last
23:44 ginseng i mean, the user would not configure this right? bitcoin core must have some defaults set
23:44 ginseng i should have specified that i plan to use bitcoin core
23:44 ginseng ultimately i am hoping to run a full node with <20GB space
23:46 praxeology yea 20GB should be fine. the command line options for pruning says 550MB, but it doesn't really say its the default or a suggestion
23:46 praxeology 550 is about 3.8 days
23:49 ginseng ok cool. thanks. pruning may make running a full node viable again