Thx, but I need to make this function itself.

So I installed geth at my server. But then what?

How this eth daemon know when receive ether? And how can I know this too?

Bitcoin .conf has [ walletnotify ] option.

But ethereum doesn't have it?

Then how can I know when receive ethereum?

The development and updates will be reasonably paced in order to prevent a hard fork from occurring.
And also, based on litecoin's update, we will also update.

I counted bitcoin address length, it is 34.

Is this all the same always?

And how about other coin's case?

If same coin, address's length is always same?

1. So if just using bitcoin daemon, send coin to address that does not exist, or wrong address. Then what happens?


2. If send ETC to ERC20 address, then it is lost?

So bitcoin's API, commands, daemon feature is same at all other alt-coins?

And eth ERC20 token does not have any source github, API, commands, daemon, right?

I don't know well about Bitgo,

What they actually provide?

Is it useful?

and are there none of similar service?


So if I want to make over 100 coin's daemon and setting it on server, are Bitgo helpful?

At many hardware (ledger nano), window application wallet (electrum), it requires choosing standard/segwit address type.

What should I choose?

Regardless of what I chosen, are there no compatibility issue between them now and future?

If there is 0.5 bitcoin in daemon wallet, then how can I send whole to another wallet?

Because there is fee, I can't type like [ sendtoaddress <address> 0.5  ], right?

Then how can I know minimum transaction fee I need to set?

How I can set at daemon?

Are there no windows 10 bitcoin wallet which does not require downloading full blockchain data?

Just need send/receive/address function.

What are needed function components for make exchange?


-User join/login, Google 2FA, My page

-Trade
All coins,
Buy/Sell,

-Databases
User's data, transaction data, coin's price chasing (option?)

-Server
webpage server, coin server

-Coin integration

-Integration with real national bank account of users

-Admin pages for exchange


What else are there more to implement?

What are these seed? m/44'/0'/111'/0/1,  m/44'/145'/48271'/0/3 ,  m/49'/0'/54'/0/0

I just thought made bunch of address from one bitcoin daemon.

Where is seed and how to know what seed used from above?

Yes I am using segwit address on ledger nano, so it does not have menu like above (MyAccount-> Account settings), nor xpub.

For example, I mined continuously some alt-coin,

and when I try to send some big amount of coin (over millions), -qt wallet program stopped and after some while,

it spit out error message that transaction size is too big, so can't send coin.

After I lower the amount of coin to send, sending executed.

So this means, for gathering million coins from too many 1000 coins mined reward,

-> transaction data size become big, can't send coin?

Then, how much size is limit and where can I revise it at source-code?


So from what I experienced, I infer like this,
----------------
A wallet have 10, 100 thousand mined record. Mine reward is 1,000 coin.

1. Try send 500,000 coins,
A wallet should gather 500 mined transactions from its own wallet, and then should sum them up and make as one pile and send to address?

-> I don't know how much filesize this become, how much this become? How much size increase per one transaction record?


2. Try send 5,000,000 coins,
A wallet should gather 5,000 mined transactions from its own wallet, and then should sum them up and make as one pile and send to address?

-> This occured error that file size is too big, so can't send coin.

So as far as I know,

old wallet can send coin with 0 fee.

But while bitcoin core updated, at some point, the rule adopted that fee can't be 0 regardless of amount of sending coin.
So now bitcoin can't be send with 0 fee, Right?

Send bitcoin to own same wallet(daemon)'s another address require fee?

To show transaction detail on blockchain explorer.

How to do using [xpub key]? How to do this? How it can send coins send straight to cold hardware storage? (I want to use ledger nano s something..)

I use new&old wallet. I manage many altcoins.

So then, following con is possible? Meet victim offline, Send bitcoin, as soon as, show him detail at block explorer with transaction ID (confirm is 0), and then take the real money from victim, then after apart from him, then anyone can reverse (or cancel) that sending?

To block this, at least 1 confirm is needed?

I can't understand... if port is different, how can those wallet can communicate each other? Even if they are emerged from same source code.