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1500 questions
21
votes
2 answers
What is the zero value for a string?
How to verify that a string, or a struct with only string properties, is initialised or not, inside of a mapping?
According to the docs, it means checking that the element of the mapping is at its 0-value, which is unclear to me when talking about…
lajarre
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21
votes
2 answers
Why is geth always returning a 0 balance?
I installed geth on a remote server (Ubuntu 14.04) and created an account. I transferred 0.01 eth to the account. From my local machine (OS X), I can view the transaction and account balance correctly with web3.
However, if I log into the server…
eterps
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21
votes
2 answers
what does "Warning: This function only accepts a single "bytes" argument. Please use "abi.encodePacked(...)" mean
In this question the OP is running into a warning upon using the keccak256 function in Solidity:
Warning: This function only accepts a single "bytes" argument. Please use "abi.encodePacked(...)" or a similar function to encode the data.
uint256…
SCBuergel
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21
votes
2 answers
How to view latest block number of a geth node in the console?
How to get information about the state of the blockchain on a geth node?
There are mentions of admin.chainSyncStatus in the documentation, but it is undefined on my 1.4.0 node. The admin.nodeInfo shows a hash for the head block, but not the…
redfish
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21
votes
4 answers
Are Whisper and Swarm still being developed?
I know that both Whisper and Swarm were is early prototype stages, with Whisper already being included in the geth client.
What is the current status of these project? I know Swarm has been largely superseded by ipfs, but there was a plan to…
Tjaden Hess
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21
votes
2 answers
By what mechanism are ASIC-based miners made less favourable?
Bitcoin mining is dominated by miners that use ASIC-based mining equipment, thereby skewing the mining rewards in favour of those able to afford large numbers of ASIC mining rigs.
Ethereum prevents this, meaning miners can still expect rewards even…
Richard Horrocks
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21
votes
2 answers
How do I find out the solidity compiler version I am using?
Specifically, while using Mist. When I create a contract via the Mist GUI, I want to then be able to verify the source code over at Etherscan. However, Etherscan requires that you provide the compiler version and whether or not optimizations were…
Micah Zoltu
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21
votes
9 answers
Block explorer running on private network
Is there any application out there that allows me to explore the Ethereum blockchain in a private network? (something similar to what blockchain.info does to bitcoin or etherchain does to ethereum public network)
Henrique Barcelos
- 2,481
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21
votes
5 answers
How to spend ether from multiple accounts?
I would like to know how to send ether from multiple accounts. For example, suppose I have 3 accounts with 5 ether in each account, how do I send the total (15 ether) to an account in a single transaction? I'm asking because from what I understand…
Paul
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21
votes
4 answers
How does one contract send ether to another contract with more than 2300 gas?
I want one contract to collect a certain amount of finney before sending it to another contract, but I can't simply send in with C2.send(thisMuch).
function() {
Dividend m = Dividend(dividendAddr);
if (this.balance >= 70 finney) {
…
Sileniced
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21
votes
4 answers
Full list of geth terminal commands
Is there a comprehensive list of the commands available in the geth terminal anywhere?
(eg. miner.start(), eth.accounts, admin.nodeInfo, etc.)
Kris Randall
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21
votes
2 answers
Call function on another contract
I've created a contract called "Name" which I've deployed to the testnet. this function just register some text for the user and display it back.
My contract is:
contract Name is mortal{
mapping(address=>string) public text;
string public…
shultz
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21
votes
2 answers
Is there length limits on Token Symbols?
Is there a limit on the length of a ERC20 Token symbol? I would like to use 4 letters, one of which is lower case, but that isn't an issue. My concern is if Exchanges have setup their tools to only handle 3 letters which is what most are today.
mazecreator
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21
votes
5 answers
Metamask: How to access/call deployed contract's functions using Metamask
I'm learning Solidity. I've set up Metamask, truffle and testrpc. I can send ether from one account to another via metamask. But I want to Metamask to access my deployed contract, and call my contract functions.
Question: Can I test and interact…
Aydin
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21
votes
7 answers
What's the advantage of EthOS over Ubuntu or Windows mining?
What exactly is the EthOs Distro? As far as I understand it's an ethereum-dedicated linux. Why should someone want to use it?
What's the advantage of EthOS over Ubuntu or Windows? What are the features? Better mining?
rethsid
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