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1500 questions
16
votes
1 answer
Structure of a transaction receipt
What does it mean line by line?
Result: {
"blockHash": "0xe6b110c9167d9aabeb13b02a7b9358d879426474a79170403d67da33a391dbdc",
"blockNumber": 665,
"contractAddress": null,
"cumulativeGasUsed": 68527,
"from":…
Roland Kofler
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16
votes
3 answers
TheDAO difference between a hard and a soft fork?
There are currently different scenarios examined which include soft or hardforking the ethereum blockchain to mitigate the DAO attack.
What plans are there exactly and what are the difference between the hard and the soft fork?
q9f
- 32,913
- 47
- 156
- 395
16
votes
5 answers
Using web3 to sign a transaction without connecting to geth
Is it possible to use the web3.js library in a client's browser to let them generate an address and sign a transaction without them connecting to an ethereum node?
Max
- 171
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16
votes
2 answers
Why was Frontier's "default" gasLimit = 3141592?
I've noticed this number at least in two places:
On the Ethereum Network Status web page.
In the sources of pyethereum.
The number looks suspiciously familiar, and I keep asking myself:
"Where have I seen it before?" and "What exactly is this…
Kostya
- 866
- 1
- 7
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16
votes
2 answers
How does the Ethereum Homestead difficulty adjustment algorithm work?
From From EIP 2, the Homestead difficulty adjustment algorithm is:
block_diff = parent_diff + parent_diff // 2048 *
max(1 - (block_timestamp - parent_timestamp) // 10, -99) +
int(2**((block.number // 100000) - 2))
where // is the…
BokkyPooBah
- 40,274
- 14
- 123
- 193
16
votes
3 answers
What does web3.eth.getStorageAt() return?
I want to know how this works: web3.eth.getStorageAt(addressHexString, position [, defaultBlock] [, callback])
What data we can store at any address and how? And what will this eth API return?
BlockA
- 857
- 2
- 7
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16
votes
2 answers
what is the role of Migrations.sol contract in truffle project?
I have started working with truffle since 4 months and I don't give importance to Migrations.sol, I thought it's just a "get started" contract.
But when I removed it caused a problem.
can anyone explains the role of this contract?
maroodb
- 1,111
- 1
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16
votes
3 answers
What are State Channels and use case/code examples?
A previous Reddit post gave some indication:
It's basically Lightning-network style payment channels but for
arbitrary state updates. Participants in the Dapp send messages with
transactions to each other that update the state but do not…
Alan Wunsche
- 1,655
- 2
- 16
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16
votes
5 answers
Send tokens using approve and transferFrom vs only transfer
We can send tokens using below ERC20 contract methods
approve() and transferFrom()
transfer()
Here if i use 2nd option the tokens are directly transferred, while if i use 1st option its a two step process
I am new to this and i want to understand…
Rishikesh Jadhav
- 161
- 1
- 1
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16
votes
8 answers
Solved: How to change Solidity linter [solc] compiler version in Visual Studio Code?
Hi may I know how to change my Solidity linter compiler version in Visual Studio Code(vscode)? OR Visual studio code how to specify solidity compiler version?
The only Solidity related extensions I have installed are solidity 0.0.38 by Juan Blanco,…
Russo
- 1,784
- 1
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- 30
16
votes
2 answers
How do I retrieve the Voted events from TheDAO?
This question was asked by @Pablo Yabo in the comment section of the question How can I view The DAO proposals including the current voting status?.
BokkyPooBah
- 40,274
- 14
- 123
- 193
16
votes
4 answers
What is the Identity function and what are its uses?
The contract at address 0x04 is the identity function. What is it and what are use cases for it?
eth
- 85,679
- 53
- 285
- 406
16
votes
3 answers
Solo Vs Pool Mining With A GPU
Currently I'm using 1 r9 380 card with 20 MH. I've only been mining for 3 days straight (72hours). I used the Mining Calculators from Etherscan and Cryptocompare. While these sites calculate it will take me approximately 1 month to solve a block for…
01infiniti
- 245
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- 9
16
votes
2 answers
Why are smart contract outputs different from ordinary transactions?
A Coinbase exchange engineer said:
"Depositing from smart contracts is hard. Smart contract outputs are
not like normal ETH transactions and it is non-trivial for us to get
notified when we receive coins from smart contracts."
Similarly, the…
bshanks
- 263
- 2
- 5
16
votes
4 answers
How can I easily parse a raw transaction?
In the Bitcoin ecosystem, there are tools like https://blockchain.info/decode-tx to decode a raw transaction. Is there a site that offers the equivalent for Ethereum?
I'm looking for an easy way to parse a raw transaction and make it human readable,…
Steve Ellis
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