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1500 questions
11
votes
2 answers
Mining Performance of AMD Radeon Pro Duo
I would like to evaluate the purchase of that GPU for Ethereum Mining. Does someone already have benchmarks?
semantium
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11
votes
2 answers
How to get the "birth block" of a contract?
How does one query the "birth block" of a contract using web3?
will_durant
- 1,154
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- 21
11
votes
2 answers
How to listen to events using Web3 v1.0?
I have a problem when listening for events from my contract.
Code js :
var Web3 = require('web3');
var abi = '...';
var contractAddress = '0x62e7Dd1Af52d5A08D401b1e156cC4CB1d2f89d57';
var eventName = 'Transfer';
//var web3;
var etat;
const web3 =…
blind
- 113
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- 5
11
votes
1 answer
How can I store big files on the blockchain?
I can hardly create transactions larger than 100kiB. I am wondering, is it possible to store huge files (several MiB or GiB) on the blockchain?
If so, how?
q9f
- 32,913
- 47
- 156
- 395
11
votes
3 answers
Geth not syncing on testnet
I'm trying to run geth on a new mac and it gets stuck when trying to sync.
I'm running geth --testnet --syncmode "fast"
This is the console output:
INFO [01-06|11:33:20] Starting peer-to-peer node
instance=Geth/v1.7.3-stable/darwin-amd64/go1.9.2…
pabloruiz55
- 7,686
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11
votes
4 answers
How do I transfer funds from an exchange to a wallet I control?
This Q&A was spawned by the fact there's no one good place with this information. All answers will be wikis. A few of us are going to be collaborating on this effort. Please keep one answer per exchange. Feel free to add whatever you can.
The…
tayvano
- 15,961
- 4
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- 74
11
votes
2 answers
What is the correct way to check if an address is zero?
I remember reading that the correct way to check if an address is 0x0 or not is _addr == address(0) and not _addr == 0. However, I'm unable to find any difference between the two when I run the following:
pragma solidity ^0.4.19;
contract Test {
…
rohithpr
- 418
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- 16
11
votes
4 answers
difference between "deploy" and "new"?
So I'm using truffle and I notice that I seem to be able to deploy a contract's bytecode by calling deployer.deploy(MyContract);
But I've also seen people run:
myContract = await MyContract.new();
in a unit test without ever calling…
mark
- 209
- 1
- 7
11
votes
2 answers
How to make parity write logs?
I'm running a parity supernode, recently switched from geth because parity seems to perform much better, even in archive mode.
To log the standard output of geth, I used to run:
geth [options] console 2>>/tmp/geth.log
I tried to run similar command…
q9f
- 32,913
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- 395
11
votes
1 answer
Is the cost of updating storage different than the cost of adding to storage?
Do these have a separate cost?
sstore(1, 10) # first time adding a value to storage with this key
sstore(1, 20) # changing the value in storage.
I looked for a list of gas costs / opcodes, and the only one I could find…
Broseph
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11
votes
2 answers
How does cryptokitties work with smart contracts and is there a random element to it?
I'm totally new to cryptokitties, but my understanding of cryptokitties so far is:
It's a smart contract that generates new kitties according to your ethereum address.
My questions are:
If you are breeding kitties, how does it handle randomness…
Patoshi パトシ
- 4,800
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11
votes
4 answers
Is there a simple Ethereum address generator that consists only of private key and public key?
I can go to https://www.bitaddress.org/ , download their software to my system, disconnect my system from the Internet, then move my mouse over their page randomly to generate entropy and then get a single Bitcoin wallet. The single wallet address…
Lone Learner
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11
votes
4 answers
How to determine if ISP is blocking Ethereum traffic
My "Ethereum Wallet" from ethereum.org used to connect to several peers. A while ago I noticed it was taking longer and longer to sync and the number of peers dropped. It got worse, and seldom connected to more than 1 peer. Now, it connects to…
user11495
11
votes
1 answer
Difference between bytecode and runtime bytecode
In Remix, clicking on "details" for a contract reveals the "bytecode" and "runtime bytecode". What is the difference?
will_durant
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11
votes
3 answers
How to verify token after etherscan, and submit icon
Sorry, my English is not good, I verified my token on etherscan, but I do not know how to change the token's icon.
user17314
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