All Questions
227 questions
3
votes
0
answers
1k
views
How to access and import presale ether without the json wallet file
I purchased ether presale. I have the public key, which shows the amount, and I have a text password I created at the time of purchase. I do not have a json drop file. How do I import my wallet? I ...
- 31
3
votes
1
answer
93
views
Is there any case where a contract will use gas?
I was wondering, why and when is it important to fund your contract with ether?
Is this really only ever if you want to send ether from your contract?
Does a contract ever need to pay gas for ...
- 195
3
votes
1
answer
1k
views
ethminer || Segmentation fault: 11 [duplicate]
I recently updated cpp-ethereum. I am now on ethminer version 1.2.3
when I start it to mine with ethminer --opencl-device 1 I get the folowing output.
Getting work package...
Segmentation fault: 11
...
- 723
3
votes
2
answers
190
views
Is there any other platform to check contract working?
I am trying from past few days but didn't get test ether to test my own contract...is there any other platform where I can test my contract or can you send me some ether
...
- 33
3
votes
0
answers
145
views
What are all the usages of ether? [duplicate]
I know that gas is used to keep contracts running but what are other usages for ether? Is ether used for buying all kinds of virtual tokens, will you need ether to use dapps or how is ether going to ...
- 861
3
votes
1
answer
2k
views
value transfer did not complete most likely as a result of a revert opcode
When i want to send some eth to an erc20 contract i receive the following error: "value transfer did not complete most likely as a result of a revert opcode".
I modified the fallback function in ...
3
votes
1
answer
221
views
ReplaySafeSplit contract on Mist v0.8.10
I'm trying to split my ETH/ETC from a presale wallet in Mist v0.8.10. I've followed the original Steemit post on running the split contract yet when I go to run the contract it doesn't show a field to ...
- 31
3
votes
1
answer
725
views
Why Are My The DAO To ETH Refunds Failing?
A user on thadao.slack.com was having trouble withdrawing their refunds from The DAO Withdrawal contact.
I checked the WithdrawDAO contact and noticed that there are many other transactions failing:
...
- 40.4k
2
votes
2
answers
838
views
How to retrieve 1 eth I send by mistake to my smart contract token?
This is the contract as you see there's one eth there https://etherscan.io/address/0x19d71f00354ad302e89ca47e59b68917f9a871d7#code.
I still have ownership of contract.
My eth stuck in smart contracts....
- 23
2
votes
0
answers
240
views
I want to reward users letting them claim tokens if they use my DApp. How do I prevent cheaters from using any other DApp?
I want to distribute tokens to users by verifying some data they provide to a DApp (for example, matching their camera photo with the database containing their faces). Since there will be thousands of ...
- 838
2
votes
0
answers
1k
views
Exchange deposits using smart contracts and externally owned accounts
While researching how different exchanges handle user deposits, I noticed a stark contrast between several prominent exchanges.
Kraken:
Exchanges like Kraken use newly generated deposit addresses (no ...
- 191
2
votes
2
answers
2k
views
Internal contract-to-contract call
I am confused with the following sentence in the Solidity documentation:
During the execution of the fallback function, the contract can only rely on the “gas stipend” it is passed (2300 gas) being ...
- 121
2
votes
5
answers
8k
views
Any shortcuts to get some test ethers for goerli test net?
let me know if you have any other ways to get some test ethers apart form(https://faucet.goerli.mudit.blog/) tweet post, fb post link and mycrypto request.
2
votes
4
answers
9k
views
How to withdraw Ether from a contract?
I am writing a smart contract which receives Ether.
How can I transfer Ether from the contract to my personal purse (non programmatically using such a program as Ethereum Wallet)?
Can I send Ether ...
- 1,854
2
votes
2
answers
2k
views
smart contract address checksum
I am going through ethereum blockchain demo's and currently trying to call other contract deployed already on a local ethereum rpc in memory blockchain.
Using truffle and ethereum rpc i am testing ...
- 131
2
votes
1
answer
323
views
How to modify the gasLimit of the private block chain on the console
as the title,How to modify the "gasLimit" of the private block chain on the console?
- 21
2
votes
2
answers
738
views
Cannot send ETH or DAO via Ethereum Wallet (Mist)
I have DAO and ETH in my Ethereum Wallet. Every time I try to send it, I input my password and press send, and it sits there saying "confirming" for a few minutes. Eventually, it just reverts back to ...
- 21
2
votes
1
answer
72
views
Purchase real Ether and add to base/default account
I created an Ethereum Consortium Leader instance on Microsoft Azure and they provided us with an Admin site and RPC endpoint:
http://someName.eastus.cloudapp.azure.com/
http://someName.eastus....
- 227
2
votes
2
answers
4k
views
How to send transaction to Infura node using Web3? [duplicate]
I want to send ETH from one account to another using Web3 interface and Infura node. I have tried like below, and I got error 405(). Error: Invalid JSON RPC response: ""
I test it in Rinkeby test ...
- 61
2
votes
2
answers
1k
views
Incoming transaction confirmed but not showing in Mist wallet
I trasnferred E10 from Kraken on 05-04-16 13:20:09 +0100 to address 0x023d29a271b2a2406ceedf208f7e36e9e24ff23d with the transaction ID ...
- 31
2
votes
1
answer
962
views
Can I rely on the fact that 'address(this).balance >= msg.value' is always true?
To my understanding, at the beginning of a payable function in a contract, an amount of msg.value ether is added to the contract's balance.
Therefore, the expression address(this).balance >= msg....
- 26.2k
2
votes
2
answers
765
views
Can't enter any commands after starting eth on Windows
I'm running the eth client (0.9.41) on Windows 10 using the following command:
eth --frontier -b -i
as stated here.
The program hangs and I'm not able to enter any commands. The last produced ...
- 893
2
votes
1
answer
594
views
How to execute smart contract code without gas or ether?
I have been trying to execute my code on remix or ethereum wallet. But to deploy my smart contract, how can I execute the code without any gas and ether. I dont need it to be online. I just need to ...
- 121
2
votes
0
answers
162
views
Read function returning blank array in geth
I have deployed a smart contract on geth which has 2 simple read, write functions in it. Then I called the write function;
e.g. payment.place_order("Laptop", 10,{from:eth.accounts[0]}).
After the ...
- 141
2
votes
1
answer
4k
views
Please help. I accidentally sent ETH to the GTH contract address
Last night I accidentally sent ETH to the GNT contract address (owing to the fact that the address was on my clipboard last and my old android phone that I have one of my wallets on did not copy the ...
2
votes
0
answers
560
views
Mist started re-syncing and ethers are gone
I downloaded the blockchain with geth --fast --cache=1024 option and size of my blockchain data after download of 2412706 blocks was around 10.9GB. I imported my accounts to keystore files and ...
- 8,076
2
votes
1
answer
91
views
How to calculate number of ETH that got bought in transaction by trading?
Let's say I have the following decoded transaction input data:
[
"0xac709fcb44a43c35f0da4e3163b117a17f3770f5",
"2500000000000000000000",
"0x0000000000000000000000000000000000000000",
...
- 325
2
votes
2
answers
10k
views
Any quick, easy ways to convert ERC-20 tokens?
Are there any quick ways to convert my Airdrop ERC-20 tokens from various old ETH wallets to ETH/BTC...? Looks like I've got a few hundred $ kicking around in old Airdrop tokens.
I've seen a few ...
- 23
2
votes
0
answers
566
views
Ether.li Wallet lost?
I created a Ether.li wallet but missed to press the finish button on the page where you note your keys.
Then i transferred money to the wallet which was not saved. After i got on the Ether.li hompage ...
- 21
1
vote
2
answers
107
views
What is the core difference between coin and token?
From googling some results, both are exchanges of value
token is limited to the project ecosystem.
coin is a general-purpose exchange of value.
But I didn't get it Bitcoin is a Coin still we buy it ...
- 113
1
vote
1
answer
918
views
Help me understand this sample code for new ERC20 token
This is my first question here so please bear with me.
I have deployed my first token on test network.
I was reading about how to improve Token contracts and stumbled upon this sample file.
This ...
- 175
1
vote
1
answer
5k
views
Minimum requirement for ether mining
I install geth and ethminer.exe and start two exe via cmd
https://i.hizliresim.com/o6Vly9.png
is this enough for mining?If yes Where will I will get coin from mining?
Should I create wallet and ...
- 123
1
vote
2
answers
10k
views
Migrating from paper wallet to Ledger Nano S with private key ONLY
I recently purchased a Ledger Nano S, and I'm wanting to transfer my Ether from my paper wallet to the new ledger device. Please forgive my ignorance, but I have no idea how I can transfer my Ether ...
1
vote
2
answers
2k
views
Should an API call be in the Solidity backend or the Javascript frontend?
I am fairly new to blockchain development. I want to call a function in my contract when a condition in the API is true. Should I make this API call in my contract, or in my frontend?
1
vote
1
answer
2k
views
Implementing EIP 155 for Signing Party
EIP-155 states:
If block.number >= FORK_BLKNUM and v = CHAIN_ID * 2 + 35 or v = CHAIN_ID * 2 + 36, then when computing the hash of a transaction for
purposes of signing or recovering, instead ...
- 13
1
vote
2
answers
581
views
How do I export ethereum blocks with quickblocks to a JSON file?
I am looking for how to export or save data from ethereum blocks in a json file
using quickblocks.
1
vote
1
answer
137
views
Etherli Problem
I bought ethereum about a year ago and transferred it to my ether.li wallet.
Now unfortunately I forgot my password and can't find the sheet I wrote it on.
I tried the "forgot password" Option but I ...
1
vote
2
answers
919
views
How do I get the price chainlink price feed when testin with hardhat?
I have written a smart contract utilizing the chainlink price feed.
Now I want to test if the prices which I calculate in my smart contract are correct.
In solidity I fetch the current USD / ETH price ...
- 195
1
vote
3
answers
471
views
When creating a new contract I receive a "contract code couldn't be stored" error but the contract is still created
Sale.new({ from: state.account, value: value, gas: 4000000 }).then((instance) => {
// do something with instance
}).catch((err) => {
alert(err)
})
When the above code runs I sometimes ...
- 123
1
vote
1
answer
117
views
My Coinbase Wallet Seedphrase is compromised
An address has taken all my Ether. My problem is that i linked my wallet with a few presale crypto. How do i go about it? How do i link a new wallet with the connected presale cryptos?
- 11
1
vote
2
answers
1k
views
Not able to assign ethers to account in private chain
I am running a testnet with init property for genesis block i am able to create an account and its working fine only problem is that i am not able to assign any pre ethers to an account which i was ...
- 455
1
vote
1
answer
545
views
Can't see my Ether in mist wallet
I withdrew Eth from Poloniex to "Account 1" in my Mist Wallet. The transaction shows it being received: https://www.etherchain.org/tx/0x4cfb836eb7a2f870c8d7e60dffec6ede16693a416fc394a8242557f8897223c6 ...
- 13
1
vote
2
answers
959
views
Deploying a simple contract to ETH Mainnet (from remix) costing $500? Am I doing this wrong?
I have a simple contract that I've tested on my ganache network, and now I'd like to push it to the mainnet. So I funded my Metamask with around $100 or 0.025 eth, figured that would be enough to ...
- 178
1
vote
2
answers
444
views
unable to use testrpc with ethereum wallet
i am trying to open ethereum wallet with testrpc to quickly test my code.
1) have opened the command prompt and entered cmd "testrpc"
2) opened another command prompt and entered cmd ""Ethereum ...
- 45
1
vote
0
answers
401
views
Catch a "require()" in frontend
I was trying to validate a transaction with some conditions on contract level and was wondering if it was possible in any way to give user feedback in the frontend if a require() fails - aka if it ...
- 23
1
vote
1
answer
2k
views
Ethereum Mining: Do miners get a fee AND create new ether as a reward? [duplicate]
So far what I get is that when I send ether or any contract via the ethereum network that I then have to pay for this transaction by paying gas (which again has a price in ether and so on). So miners ...
- 11
1
vote
1
answer
897
views
Simpler verification of externally-created ECDSA signatures in Solidity
I just want to use ecrecover to verify with a public key that the corresponding private key signed a message passed through a variable in solidity. What's the simple way to do this? I have inserted ???...
- 77
1
vote
1
answer
529
views
eth_getLogs was only return erc20 tokens
i have used below command to get every logs on the special blocks but its only return erc20 token logs and ethereum transactions was not listed.
my geth command:
curl --data '{"method":"eth_getLogs",...
- 145
1
vote
2
answers
1k
views
What is the full block reward? [duplicate]
The Ethereum launch process states that with the release of Homestead, the Ether mining will be at 100% rather than 10% of the usual reward rate.
Does that mean the full block reward would be 50 ...
- 33k
1
vote
2
answers
1k
views
Get All Contracts from Blockchain
I am developing a large database of exploitable contract addresses and creating a website to host such a database for users to use to see if contracts are safe.
Is there a way to get all contract ...
- 383