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1500 questions
23
votes
3 answers
What is knownStates?
I am using geth client (VERSION: 1.4.12-stable-421df866)
to sync to the Ethereum testnet. To check the status of the sync, I ran web3.eth.syncing in the geth console. This is the output I see:
{
currentBlock: 1743872,
highestBlock:…
maheshmurthy
- 1,237
- 2
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- 17
23
votes
3 answers
This contract may be abstract, not implement an abstract parent's methods completely or not invoke an inherited contract's constructor correctly
I'm trying to test out Ampleforth on Rinkbey using Remix. Here are all the files that I copy into remix.
https://github.com/cryptoghoulz/based-contracts/tree/master/contracts/v4
They compile fine, but when I deploy UFragments I get this error:
This…
Richard Garfield
- 1,017
- 2
- 10
- 14
23
votes
4 answers
Error "no key for given address or file" when unlocking coinbase account
Using json-rpc eth_unlockAccount() method I can unlock everyone of my node accounts except coinbase. When trying to unlock coinbase account, geth responds with the message:
no key for given address or file.
I've bee reading Ethereum Wallet: error…
Juan Ignacio Pérez Sacristán
- 3,550
- 9
- 43
- 73
23
votes
3 answers
Math operation between int and uint
How is it possible to either convert uint to int or do simple math comparison operations?
Something like:
uint a;
uint b;
int c;
if (a - b < c) doSomething();
What I'm trying to do is to see if the subtraction of two integers are negative or not.…
Shayan
- 895
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- 8
- 24
23
votes
4 answers
Unlocking accounts and making transactions in web3.js
This question is related to this one and this one. It also has a partial answer here and here.
In the third link the account is being unlocked for a period of time using web3.js:
web3.personal.unlockAccount("0x..", "", 1000);
The unlock…
Sebi
- 5,294
- 6
- 27
- 52
23
votes
5 answers
Conversion of uint to string
I am trying to convert uint to string in solidity. Is it possible to convert? if so how can I convert it?
Convertion to base 10 is prefered, but in hexadecimal might also be helpful.
madhan siva
- 581
- 1
- 4
- 8
23
votes
1 answer
In geth, `eth.syncing` gives `false` even when blocks are imported
I issue eth.syncing and get false even when at the same time blocks are imported. Is this correct behaviour?
Using geth version 1.4.6
TMOTTM
- 1,953
- 2
- 14
- 23
23
votes
1 answer
Can anyone explain what's the difference between mist/geth/parity in simple terms?
What's the difference between geth/mist/parity?
Krishna
- 251
- 2
- 3
23
votes
2 answers
What are the types of nodes in Ethereum?
I have seen the usage of the word full node many times. What exactly is an Ethereum full node? What are bootstrap nodes and light nodes/clients? Are there any other types of nodes?
galahad
- 3,920
- 3
- 26
- 66
23
votes
3 answers
How do Ethereum mining nodes maintain a time consistent with the network?
We have established that the timestamp on a parent block has to be before the timestamp of a child block in Can a child block have an earlier timestamp than the parent block?.
How are differences in the clock settings on different miners' computers…
BokkyPooBah
- 40,274
- 14
- 123
- 193
23
votes
2 answers
What type of operations have negative gas costs?
I understand that some operations cost negative gas because they free up space on the blockchain, such as selfdestructs. What are all the operations that can have negative gas? Does this only occur because the operation ultimately frees up space…
DirtStats
- 656
- 5
- 16
23
votes
3 answers
Account uniqueness guaranteed?
When we create an account in the Ethereum main network, how does the protocol guarantee the unique address of an account? Since even if we are not connected to the network we can create an account, is there a possibility of two accounts getting the…
Abhiram mishra
- 1,922
- 1
- 13
- 23
23
votes
12 answers
The reason for "Could not find artifacts for" in truffle?
Any ideas about the reason for the following error from truffle? The contract is from the solidity docs.
Truffle.js -
//var Set = artifacts.require("./Set");
var Consumer = artifacts.require("./Consumer");
var Infofeed =…
Trevor Lee Oakley
- 2,327
- 2
- 19
- 48
23
votes
2 answers
Gas price in ETH unit
I am wondering if there's a website that provides the price of the standard gas limit (21000 Gas, transaction cost for sending ETH) in ETH unit.
I checked Ether.Fund site, but it provides the gas price in BTC and is based on ether pre-sale rate.
suburhok
- 401
- 2
- 4
- 6
23
votes
7 answers
How can I return an array of struct from a function?
I know that it's possible to return a struct through argument destructing:
contract Test {
struct Point {
int x;
int y;
}
Point point;
function getPoint() returns (int x, int y) {
x = point.x;
y =…
Henrique Barcelos
- 2,481
- 4
- 20
- 38