I am researching bitcoin/litecoin source.

I am trying to revise and start new block, create genesis block.

So I changed genesisOutputScript variable at chainparams.cpp  52 line, via [ cat genesiscoinbase.hex ]

and then changed below line's source like following..

Code:

pchMessageStart[2] = 0xb1;
        pchMessageStart[3] = 0xde;
        nDefaultPort = 2454;
        nPruneAfterHeight = 100000;

        genesis = CreateGenesisBlock(1518706741, 2084524493, 0x1e0ffff0, 1, 50 * COIN);
        consensus.hashGenesisBlock = genesis.GetHash(); 
	printf("genesis.GetHash = %s\n", genesis.GetHash().ToString().c_str());
	printf("genesis.hashMerkleRoot = %s\n", genesis.hashMerkleRoot.ToString().c_str());
        assert(consensus.hashGenesisBlock == uint256S("0xf333b8dff21df2ec0034590afa921a09e43ff41c5c8e5ac10cd83bf17615554d"));
        assert(genesis.hashMerkleRoot == uint256S("0xc4ef14392acd1d6123ab6b4497601f2a164e50f5da77903dc7e2ad1a8fa25f2d"));

        // Note that of those with the service bits flag, most only support a subset of possible options
        vSeeds.emplace_back("something.something.com", true); 

        base58Prefixes[PUBKEY_ADDRESS] = std::vector<unsigned char>(1, 55);
        base58Prefixes[SCRIPT_ADDRESS] = std::vector<unsigned char>(1, 55);
        base58Prefixes[SCRIPT_ADDRESS2] = std::vector<unsigned char>(1, 55);
        base58Prefixes[SECRET_KEY] =     std::vector<unsigned char>(1,176);
        base58Prefixes[EXT_PUBLIC_KEY] = {0x04, 0x88, 0xB2, 0x1E};
        base58Prefixes[EXT_SECRET_KEY] = {0x04, 0x88, 0xAD, 0xE4};

        vFixedSeeds = std::vector<SeedSpec6>(pnSeed6_main, pnSeed6_main + ARRAYLEN(pnSeed6_main));

        fDefaultConsistencyChecks = false;
        fRequireStandard = true;
        fMineBlocksOnDemand = false;

        checkpointData = (CCheckpointData) {
            {
                {  0, uint256S("0x001")},
            }
        };

        chainTxData = ChainTxData{
            // Data as of block 59c9b9d3fec105bdc716d84caa7579503d5b05b73618d0bf2d5fa639f780a011 (height 1353397).
            1518706741, // * UNIX timestamp of last known number of transactions
            0,  // * total number of transactions between genesis and that timestamp
                    //   (the tx=... number in the SetBestChain debug.log lines)
            0.06     // * estimated number of transactions per second after that timestamp
        };

but after compile this with 'make' , then run ./litecoind  ,
error says,

genesis.GetHash = f333b8dff21df2ec0034590afa921a09e43ff41c5c8e5ac10cd83bf17615554d
genesis.hashMerkleRoot = c4ef14392acd1d6123ab6b4497601f2a164e50f5da77903dc7e2ad1a8fa25f2d
Error: Error: A fatal internal error occurred, see debug.log for details
Segmentation fault (core dumped)


and here is debug.log file says,

2018-02-15 15:23:10 Litecoin version v0.15.1.0-845fc69ab-dirty
2018-02-15 15:23:10 InitParameterInteraction: parameter interaction: -whitelistforcerelay=1 -> setting -whitelistrelay=1
2018-02-15 15:23:10 Assuming ancestors of block 59c9b9d3fec105bdc716d84caa7579503d5b05b73618d0bf2d5fa639f780a011 have valid signatures.
2018-02-15 15:23:10 Setting nMinimumChainWork=00000000000000000000000000000000000000000000002ebcfe2dd9eff82666
2018-02-15 15:23:10 Using the 'standard' SHA256 implementation
2018-02-15 15:23:10 Using RdRand as an additional entropy source
2018-02-15 15:23:10 Default data directory /home/ubuntu/.litecoin
2018-02-15 15:23:10 Using data directory /home/ubuntu/.litecoin
2018-02-15 15:23:10 Using config file /home/ubuntu/.litecoin/litecoin.conf
2018-02-15 15:23:10 Using at most 125 automatic connections (1024 file descriptors available)
2018-02-15 15:23:10 Using 16 MiB out of 32/2 requested for signature cache, able to store 524288 elements
2018-02-15 15:23:10 Using 16 MiB out of 32/2 requested for script execution cache, able to store 524288 elements
2018-02-15 15:23:10 Using 4 threads for script verification
2018-02-15 15:23:10 scheduler thread start
2018-02-15 15:23:10 HTTP: creating work queue of depth 16
2018-02-15 15:23:10 No rpcpassword set - using random cookie authentication
2018-02-15 15:23:10 Generated RPC authentication cookie /home/ubuntu/.litecoin/.cookie
2018-02-15 15:23:10 HTTP: starting 4 worker threads
2018-02-15 15:23:10 init message: Verifying wallet(s)...
2018-02-15 15:23:10 Using BerkeleyDB version Berkeley DB 4.8.30: (April  9, 2010)
2018-02-15 15:23:10 Using wallet wallet.dat
2018-02-15 15:23:10 CDBEnv::Open: LogDir=/home/ubuntu/.litecoin/database ErrorFile=/home/ubuntu/.litecoin/db.log
2018-02-15 15:23:10 Cache configuration:
2018-02-15 15:23:10 * Using 2.0MiB for block index database
2018-02-15 15:23:10 * Using 8.0MiB for chain state database
2018-02-15 15:23:10 * Using 440.0MiB for in-memory UTXO set (plus up to 286.1MiB of unused mempool space)
2018-02-15 15:23:10 init message: Loading block index...
2018-02-15 15:23:10 Opening LevelDB in /home/ubuntu/.litecoin/blocks/index
2018-02-15 15:23:10 Opened LevelDB successfully
2018-02-15 15:23:10 Using obfuscation key for /home/ubuntu/.litecoin/blocks/index: 0000000000000000
2018-02-15 15:23:10 LoadBlockIndexDB: last block file = 0
2018-02-15 15:23:10 LoadBlockIndexDB: last block file info: CBlockFileInfo(blocks=0, size=0, heights=0...0, time=1970-01-01...1970-01-01)
2018-02-15 15:23:10 Checking all blk files are present...
2018-02-15 15:23:10 LoadBlockIndexDB: transaction index disabled
2018-02-15 15:23:10 Initializing databases...
2018-02-15 15:23:10 Pre-allocating up to position 0x1000000 in blk00000.dat
2018-02-15 15:23:10 Opening LevelDB in /home/ubuntu/.litecoin/chainstate
2018-02-15 15:23:10 Opened LevelDB successfully
2018-02-15 15:23:10 Wrote new obfuscate key for /home/ubuntu/.litecoin/chainstate: 926d8d907f958c5b
2018-02-15 15:23:10 Using obfuscation key for /home/ubuntu/.litecoin/chainstate: 926d8d907f958c5b
2018-02-15 15:23:10 init message: Rewinding blocks...
2018-02-15 15:23:10  block index              18ms
2018-02-15 15:23:10 init message: Loading wallet...
2018-02-15 15:23:10 nFileVersion = 150100
2018-02-15 15:23:10 Keys: 0 plaintext, 0 encrypted, 0 w/ metadata, 0 total
2018-02-15 15:23:10 Performing wallet upgrade to 60000
2018-02-15 15:23:10 keypool added 2000 keys (1000 internal), size=2000 (1000 internal)
2018-02-15 15:23:10 keypool reserve 1
2018-02-15 15:23:10 keypool keep 1
2018-02-15 15:23:10  wallet                  738ms
2018-02-15 15:23:10 keypool added 1 keys (0 internal), size=2000 (1000 internal)
2018-02-15 15:23:10 setKeyPool.size() = 2000
2018-02-15 15:23:10 mapWallet.size() = 0
2018-02-15 15:23:10 mapAddressBook.size() = 1
2018-02-15 15:23:10 ERROR: ReadBlockFromDisk: Errors in block header at CBlockDiskPos(nFile=0, nPos=8)
2018-02-15 15:23:10 *** Failed to read block
2018-02-15 15:23:10 Error: Error: A fatal internal error occurred, see debug.log for details


So what is the problem? What am I missing? How to fix and can make my own genesis block?

Thanks.

I am searching bitcoin(or litecoin) source copying, making new alt-coin tutorial.

I googled and saw every threads in this forum, and other sites,

so far there is none based on newest source. (0.15.1)

So all datas written there are incomplete. some still can be applied, some not.

Are there none of it?

So bitcoin block generation speed is 10 minutes, is this minimum transaction speed?

Then how can faster it?

I find at 'chainparams.cpp', consensus.nPowTargetSpacing = 10 * 60;

So this is 10 minutes, so if I change it to 0.1 * 60, then transaction speed also become 6 seconds?

What else parameters should I change to speed up?

From newest bitcoin/litecoin source,

So I testing make new genesis block, based on new blockchain.

So I changed at 'chainparams.cpp'
pchMessageStart[0~4] value to random value for start new blockchain, (is this right?)

and also I changed following line's

consensus.hashGenesisBlock == uint256S("0x............");
genesis.hashMerkleRoot == uint256S("0x.....");

to value of mine. (knowing by printf code added above these lines)

After compile ('make'), run by ./bitcoind

but error says 'A fatal internal error occured, see debug.log file'

and debug.log says at end,

ReadBlockFromDisk : Errorrs in block header at CBlockDiskPos(nFile =0, nPos =


Maybe I need to revise more elsewhere to start new blockchain?
How to fix?

Thanks.

I now trying to change variables of bitcoin source and make own.
 
For that maybe I need to change hashGenesisBlock's value to match to my block?

so I revised source like this,

chainparams.cpp : 123~126 line around approx.

assert(consensus.hashGenesisBlock == uint256S("0x"));   // deleted whole after '0x' to spit out error and then debug.log file will show the right value?

but after try, debug.log file itself does not generated, and to take this code change effective, tried compile, but this error.

http://naver.me/55BHuWIC

How to do fix?

Thanks.

So for make own coin, I need to change 2 variables about merkleRoot hash value?

at (chainparams.cpp),

consensus.hashGenesisBlock = uint256s("0x2rj203rfjdlakjf3..........));
genesis.hashMerkleRoot = uint256s("0xf2094ur293228ry289.......));

How to change this to right one?

If I have new coin idea, then what?

Write about idea (white paper or whatever), then where to register it to spread it to public ICO investors?

Should I first setup ethereum token distribution system?

Originally it was at src/Main.h file's  following function.

--------

Code:

static bool AllowFree(double dPriority){
        return dPriority > COIN * 576 / 250;
}

But new source doesn't have this part itself.

Where it gone? Or to what shape changed?

So bitcoin uses sha256, litecoin scrypt, dash x11.

Where is revision location(source code filename, approx line position)  of this algorithm?

Is it widespread and hard to revise? or easy to change?

How change to x11 algorithm? Some site says x11 is best algorithm.

I know 21,000,000 is maximum bitcoin number.

Now its remaining 4,000,000 approx.

So its over at 2140 year?

What happen then? If all mined, all current many miner hardwares (ASIC) all become trash?

Or they can continue finding new block, but reward is only bitcoin transaction fee?

So there are many web-wallet services providing sites.

How they program it?

Are there bitcoin's opened API to generate wallet and address to receive coin?


How about other alt-coin's cases?

If that coin is based on bitcoin sources and copied, then they also automatically provide API?

Most articles, datas got googled based on very older version, even 4 years ago.

At that time's version, there is file of src/Main.cpp, src/Main.h  where some key parameters existed.

But recent source (Bitcoin, 0.15.1) does not have above files (Main.cpp, Main.h).

Maybe source code there was moved?

To where and how to locate them all to make alt-coin?
Are there no tutorial or documents about source code location changing guide?

So for ICO, website need.

Basically it does ICO automatic coin distribution.

It should provide automatic system with account making, coin adding in exchange of user's deposit of Bitcoin, Ethereum, etc.

And dashboard, web wallet of that ICO coin.

For side feature, FAQ, contact support, calander function with coin buying cap and bonus rate schedule, etc.

Are there solution for this? Or all ICOs doing this job on their own with web developer?

I heard that most recent icos uses Ethereum platform and make tokens on it.

Is this best option now?

How about cloning Bitcoin or litecoin and start new coin?

What is more good and why?

Thanks.

I know Bitcoin Diamond give away some portion of their coins to Bitcoin owners for just free and without any acting of owners. One day it just generated even before knowing of that.

Their intent of this act is of course for promoting & advertising their coins?

Then how they perform this? Are there any code example of executing this?

Thanks.

So now there are many ICOs, new coins.

Where most of them keep some ratio of coins for themselves to use develop, marketing.

1. Then techinically (programming point of view), how to give some coin to some specific wallet address or some user account even before system started and before genesis block started?


2. And sell those coins to make develop, marketing money.
How to give away coins to normal users worldwidely in exchange of their money (USD, BTC)?


3. Are there example code for abvoe 1,2 process?


4. Until all pre-sale, ICO ended, coin system is not started yet, right?


Thanks.

1. How bitcoin system can block bad intent sources?

What happen if someone revise bitcoin source and launch it as like bitcoin?

If he has intend that he will take some bitcoin?


2. How bitcoin system can adopt legitimate improvement, changes of sources?

There is many volunteers developers to bitcoin sources, continuously updated bitcoin sources.

Who decide adoption of changes and how it can be spread to normal bitcoin system users worldwide?

I know Bitcoin Cash is almost same with bitcoin. Just few parameters different.

How can I create like that? I got bitcoin source downloaded, forked to my git account, installed vmware workstation and there I installed ubuntu.

Then what? Bitcoin source file revision?

Where is location of specific parameters?

Are there no tutorial or documents, video about this subject? (Bitcoin copied altcoin)

Thanks.

Correct me if I know wrong.

I know the reason like this,

If some programmer want to revise the bitcoin source and after done, for test, he need to compile revised source to make new running file, -qt.exe

Is this right?

Thanks.

I want to make alt-coin.

I want to do this without install ubuntu. Can I? Is this possible?


And why compiling process need? Compiling bitcoin source is really hard in windows 10, right?

And there is already compile done -qt.exe file at googling.

But if I change parameters at source code, then I need to recompile and make another version's -qt.exe file?