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1500 questions
23
votes
11 answers

Are there any rinkeby testnet faucets that don't require social network accounts?

Are there any rinkeby testnet Faucet's that don't require social network accounts? https://www.rinkeby.io/#faucet wants requests centralized twitter/g+/fb posts.
Victory
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23
votes
3 answers

How to get current time by solidity?

I'd like to describe time like Apr15th 10:00AM . I know how to describe time range as follows, but I am not sure how to call date of time. Could you tell me about it if you know? 1 == 1 second 1 minutes == 60 seconds 1 hours == 60 minutes 1 days ==…
Toshi
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23
votes
2 answers

Explanation of Parity Library Suicide

So today, A vulnerability found within the Parity walletLibrary which resulted in freezings of potentially hundreds of millions of dollars from wallets using parity multi-sig. Can someone technically explain how this was abused? Here is link to…
NowsyMe
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23
votes
5 answers

How to convert BigNumber to Number in Truffle framework?

I have written an ERC20 token contract and deployed it in test network using truffle framework. When I check the token balance for an account using web3 it was giving the result in BigNumber when I try to convert it to a number using toNumber()…
Karthikeyan Thangavel
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23
votes
4 answers

Solidity - List contains

given address[] wallets. What is the correct method to check that the list contains a given address? Does solidity provide any native list contains function? If not, is the only way to do a full iteration of the array and check each element? Are…
monokh
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23
votes
1 answer

How to find solidity code for a contract address

I need to find out the public contract code i.e. solidity code for a contract address. For eample, here it has a tab for contract code but it's in assembly and byte code only, which is not useful. I need to find out method signatures so that I can…
garg10may
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23
votes
2 answers

Meaning of 'using SafeMath for uint256;'

Hi I just started to study solidity. Can you tell me what is using SafeMath for uint256;? https://github.com/decentraland/mana/blob/master/contracts/ContinuousSale.sol#L10
zono
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23
votes
2 answers

Why is my ether balance 0 in geth, even though the sync is nearly complete?

My geth --fast sync is nearly complete, and the balance shows correctly on Etherscan. I was running geth on linux and haven't synced in a while, so I deleted the chaindata and updated the wallet and started re-syncing with geth --fast. Even after…
user17499
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23
votes
2 answers

How to get Source code of an already deployed contract?

How can I retrieve the solidity code of an already published contract in the mist wallet?
tokyomonogatari
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23
votes
1 answer

At which point the smart contracts get executed?

Let's say I sent a transaction to invoke a smart contract (to its address). At which point will the smart contract get executed? Is it during the transaction validation process? Also, is there any limit on how long a smart contract can run on? For…
23
votes
4 answers

How can I empty the blockchain?

I am trying to do a fast sync using geth --fast but I am getting this message: blockchain not empty, fast sync disabled How can I empty the blockchain to allow for fast sync?
Randomblue
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23
votes
6 answers

How to remove gas system from ethereum

I'm testing Ethereum with a complex contract which requires quite a lot of gas. And I'm testing (and will be running) a private network with controlled miners, so I don't need them getting any reward, and my "coin" is not ether. Currently I'm…
BiS
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23
votes
2 answers

Difference between a pruned and unpruned blockchain

At the Berlin Blockchain Meetup, Gustav Simonsson teased the Homestead release coming soon (tm) and we were discussing blockchain bloat and the current size of the Ethereum blockchain. We discussed the pruned and unpruned blockchain and the geth…
q9f
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23
votes
5 answers

Is there a C# implementation available for Ethereum?

Is there a C# / .NET / Mono implementation available for Ethereum to interact with nodes and/or the blockchain?
q9f
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23
votes
5 answers

How to estimate gas at contract creation/deployment to private ethereum blockchain

What I have done a) When I use web3.eth.estimateGas to estimate the cost of a contract creation constructor with no parameters, the estimate is correct. b) If the contract is already deployed then estimating the gas cost of a contract function with…
Imroz
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