where in the source code is the the proof of work checking the blockheader hash and nonce?

where in the source code is the the proof of work checking the blockheader hash and nonce?

Where in the source code do we check whether

 hash(blockheader*nonce) < Difficulty

In fact, the line I found is as follows: https://github.com/bitcoin/bitcoin/blob/v0.17.0.1/src/pow.cpp#L87

My problem with this is 3-fold

a) this is not the code that miners use to perform the check; it probably is the validation on node-side ?

b) here the "hash" refers to what exactly ?

c) why is this value tested against nTarget ? rather than Difficulty ?

d) this check is usually advertised in media as "<"less rather than "<=" less than equal. But seeing how this line is coded , it means HASH<= nTarget is OK.

https://ift.tt/2NhiSZA

Comments

Post a Comment

Popular posts from this blog

Activation of SegWit v1

Activation of SegWit v1 The segregated witness soft fork of August 2017 included a versioning field which would allow for future incrementation. Anthony Towns has recently posted an early draft of the proposal for the SegWit v1 upgrade to the mailing list . Although the devil is of course in the details, how could such an upgrade process look like? What are the different upgrade mechanism for the major [v1 - v16] and minor [v1.0 - v1.127] version changes? How is the soft fork signaled? How is the consensus change enforced? Is the v1 change as "contentious" and time consuming as v0 was? What are the tasks of node operators and miners? Thank you in advance for the answer! https://ift.tt/2VrPDpG
Read more

Why the Coinbase customer support 1(855)750-0786 is always busy?

Why the Coinbase customer support 1(855)750-0786 is always busy? My account has been freezed. Last month i had same issue and support staff helped me to recover my money.But since two days i am facing same issue cannot transfer my funds.I tried calling Coin base support 1(855)750-0786 but all lines are busy and busy tone i am getting right now. https://ift.tt/2qbzPts
Read more

Insta-mining problems, how to prevent being outgunned? And difficulty + adjustments

Insta-mining problems, how to prevent being outgunned? And difficulty + adjustments I created a new coin to learn something about Bitcoin. I cloned the source code, called it something different, put a new logo on it, nothing major. Then I made some nodes available, and put the source on github. The number of connections (aside from me) to the nodes reflected the number of git clones. I'm sure I had an instamine problem, where the hashrate went up and the difficulty went up so that I wasn't able to catch up quick enough and outgun the miners. Even when I did point significant hashpower at my new pool, I just made the difficulty go way up. I mined blocks, but they were orphaned. So was I mining on a different chain? i.e. the "wrong" one that broke off from the original that I wanted to catch up with? There have been some ideas on preventing an instamine. One is to mine a large number of blocks, and before putting out the source code and making it available for anyone...
Read more