All Questions
519 questions
1
vote
1
answer
174
views
Smart Contract Balance = 0
Ok, I am pretty new to developing contracts, and I did so by using dAPP and truffle. But when adding it to the chain, it says there is no balance to the contract. How can I add tokens to be bought? ...
1
vote
1
answer
342
views
Best practice in 2018 to claim Ethereum presale purchase [duplicate]
I have the presale wallet and password, but went through a number of trials and just now trying to get back on my feet. I have yet to claim my presale and could really use it to help with medical ...
- 11
3
votes
3
answers
15k
views
How to fetch ETH/USD price from the coinmarketcap api
I want to fetch the current ETH-USD price from this api (https://api.coinmarketcap.com/v1/ticker/ethereum/?convert=USD). How do I fetch just the price into a variable in PHP for reuse on my ...
1
vote
2
answers
3k
views
Internal Token Transfer without ETH fee
Need to move all token from one address to another address(Internal) without fees. Could you please help me to solve this?
- 11
0
votes
1
answer
249
views
Transaction Pending and Dropped
I have a transaction pending from 4 days.
I have tried to unlock following this answer:
MyEtherWallet is pending and dropping. It looks like it is stuck in a loop for 2 days?
Now the current nonce is ...
- 1
2
votes
0
answers
500
views
Hashing Algorithm Equality in zk-SNARK [closed]
I am looking to implement the zk-SNARK capabilities of Ethereum to allow a user to prove that they have all the components required ('a', 'b', 'c', 'd') to create a publicly known hash 'x'. My general ...
- 21
0
votes
1
answer
68
views
How to define miners ACL on a private chain
is there a way to manage "allowed" miners in ethereum private chain ?
the idea is to have some sort of access control list of miner addresses which are allowed to seal a block.
in case the above is ...
- 167
3
votes
1
answer
755
views
Details about w3.eth.account.create()
I am currently getting started into developing involving Ethereum. I know what the function w3.eth.account.create() does and returns but I am unsure what happens behind the scenes.
Specifically, ...
- 65
-1
votes
1
answer
212
views
Generate ETH address with button on my website
I'd like to open a website that I can easily generate an ETH address like this website: http://taschh.com/microworkers/cv/generate/
Of course, I will have all of ETH address and its private key.
I don'...
- 1
8
votes
2
answers
475
views
How can I maximize the probability that my ETH nodes stay synchronized with mainnet for as long as possible?
I run three full ETH nodes, one on my local, home network, and two in the cloud. All three make use of geth.
My "local" node, is always in sync with mainnet, i.e. always showing the same last block ...
- 303
1
vote
0
answers
97
views
Can the unitsOneEthCanBuy value be changed after Token creation? [closed]
How can I change the value of "unitsOneEthCanBuy" in the contract ?
(As the Token is only created & ICO has n't happened)
- 11
5
votes
4
answers
807
views
Why do you want to use different implementations of EVM?
Currently there are many implementations of EVM (Java, C++, Python, Go, etc).
For example: I will be using Solidity to write DApp on the top of EVM-Java and EVM-Python, why would I want to use EVM-...
- 461
1
vote
1
answer
1k
views
how to batch send eth or erc20 from multiple address to one address?
How to batch send eth or erc20 from multiple address to one address?
How to do it with code?
For example, I have 30 eth address.
I want to from 30 eth address Transferring to the one account in ...
- 11
1
vote
2
answers
2k
views
Does an ERC-20 token transfer cost more gas than an ETH transfer?
After messing around on the Remix IDE, I realized that initializing a uint (to any value other than 0) costs about 20,000 gas. Because of this, an ERC-20 token transfer to an account with balance 0 ...
- 655
2
votes
2
answers
2k
views
Decoding ethereum leveldb keys and values
I've created a simple script to read ethereum data from the leveldb using C++. Basically this testing program would print all keys in leveldb to the console.
#include <cassert>
#include <...
- 61
0
votes
2
answers
8k
views
How to listen to events generated by an existing contract in web3 1.x.x?
Currently I'm unable to find a working solution. Let's say I have the following smartcontract:
contract Manufacturer {
event LogNewOrder(string order);
string[] public orders;
function ...
- 161
1
vote
0
answers
128
views
Library for create ethereum wallet
I want to create an ethereum wallet that is erc20 compatible on my client side.
It should allow user to enter his own password and generate private key, recovery phrases and utc file.
I try to ...
- 141
1
vote
3
answers
1k
views
Ethereum mining pool
Guys I want to build a mining pool for ethereum which is based on GPU mining.
I've searched alot but I couldn't find anything except genoil(cpp-ethereum) which supports GPU mining but the creation of ...
- 143
2
votes
2
answers
2k
views
Why don't private blockchain networks that do not charge for transactions charge a fee when processing ethereum/ proprietary token on the network?
I ask this questions is there seem to be 2 flavors of blockchain: 1. Public think bitcoin and ethereum. 2. Private hyperledger, SAP Leonaro, etc. The public network charges for transactions which make ...
- 21
2
votes
2
answers
2k
views
Delete/hide ETH address on Ledger Nano S
Is it possible to delete / hide one of ETH addresses that my Ledger Nano S is providing after logging via MyEtherWallet?
I know ledger is allowing me to use lots of addresses. It is displaying the ...
- 21
0
votes
1
answer
730
views
Can I solo mine ethereum instead of pool?
I am running a single rx 480 at 22mh/s, this rig is not geared towards mining and I’m doing it for fun. Would I be able to solo mine ethereum blocks for a higher payout? Or should I stick to pool ...
0
votes
2
answers
3k
views
Solidity Smart Contract auto withdrawal (ETH)
I'm kinda new to smart contracts, searched a lot, but hope someone here can help me out.
I'll try to explain as good as I can. I'm mining Ethereum with a couple of rigs.
Each individual rig auto-...
1
vote
1
answer
30
views
tokens and coins based on ETH
I intend to trade tokens and coins using MyEtherWallet. Is it possible to use MEW to do Tx's between ALL coins and tokens, or is the wallet limit to a specific list?
- 11
3
votes
1
answer
2k
views
Invalid address error
I keep getting Error: Invalid address when trying to run the application.
My current setup of web3 using infura node is
if (typeof web3 !== 'undefined') {
web3 = new Web3(web3.currentProvider);
} ...
- 31
0
votes
2
answers
1k
views
How to make an action to send record to my database?
I want all transaction of the tokens send to my database through smart contract.
For example, A send 10Token to B, it will show on blockchain, but I also want a function which smart contract will let ...
- 1
2
votes
3
answers
852
views
Hi, is Ethereum MIt licensed?
is Ethereum MIt licensed? Can we use it for business purpose?
1
vote
1
answer
235
views
Everyone is asking Now is Ethereum still ASIC Resistant? [duplicate]
According to Bitmain - plus other 3 company in china, that they will lunch Asic Miner Machine for Ethereum this 2nd Quarter 2018.
My question is there any way that ethereum can prevent this to happen?...
- 11
0
votes
1
answer
1k
views
Convert contract arguments to ABI-encoded format
My Contract Source
https://gist.github.com/munggo/ed25afb0aff9169a6c57f1d464d13177
Convert contract arguments to ABI-encoded format
How???
0
votes
2
answers
547
views
solidity - forever can't return the msg.sender balance
this is my contract code
pragma solidity ^0.4.4;
contract IamHongKongTokenBack_00{
// 現在我錢包的地址+Eth量
function SeeMyAddAndETHVar() public constant returns (address, uint) {
address _myadd = msg....
0
votes
1
answer
271
views
Verify Contract Code Eth
I'm trying to verify an erc20 Contract code for a few days.
I have read a lot and tried but just can not get on. maybe someone can help me?
Here are the dates:
/*
Implements EIP20 token standard: ...
- 3
2
votes
1
answer
9k
views
CUDA ERROR : Cannot allocate big buffer for DAG
Windows Config
Windows 10
Ram 8GB DDR4
1TB HDD
Vertual Ram set max at 20000mb
Still having CUDA error.
GPU GTX 1060 3 GB x 2
GPU GTX 1060 6 GB x 3
Total 5 GPU
- 21
1
vote
1
answer
329
views
web3.admin.addpeers return BigNumber Error
When I using ethconsole to deal with a private chain. I hope it can connects to another node which I get the node information.
But the command "web3.admin.addPeer("enode://[email protected]:30304",...
- 13
0
votes
1
answer
185
views
cpp-ethereum Current block number is 0
I have using eth --private "customChain" --genesis-json genesis.json --db-path data" to create a private chain.
and when I into ethconsole it shows:
Connecting to node at \\.\pipe\geth.ipc
Connection ...
- 13
0
votes
1
answer
129
views
Do I need to have my account unlocked for a mining pool
I have a mining pool and I'm using geth. Do i need to keep my pool wallet unlocked in geth in order for the pool to work? Includes unlocking blocks and sending payments to miners on the pool.
- 3
0
votes
1
answer
109
views
Feedback the cheat and fraud of etc eth on twitter. How can i recover my loss?
Eth and etc arg two great projects.
As i can't find the etc email, hope you can kindly cc to etc too, thanks.
A few days ago on Twitter to search for the etheric classic, found an account, and read ...
- 11
0
votes
1
answer
96
views
What happens to the ETH if the contract is canceled?
I sent ETH to a company during their ICO. The contract, on Etherscan shows, Warning! Error encountered during contract execution [Bad instruction] and the contract was canceled. My question is what ...
- 3
5
votes
3
answers
6k
views
How store ETH in a smart contract
The question it's How store Ether in a smart contract.
In first step, I try transfer the transaction value to the smartcontract address doing something y something like that:
function storeETH() ...
1
vote
2
answers
102
views
Is it possible to fork ethereum so that only specified account(s) can deploy new contract?
Blockchains supporting smart contract are sometimes compared with smartphones in the sense that it is an infrastructure opened to host an indefinite number of Apps, any participant can create and ...
- 73
-1
votes
1
answer
269
views
Whats wrong with this?
I know I'm not actively mining eth but I can't figure out whats wrong:
Found suitable OpenCL device [Turks ] with 2147483648 bytes of GPU memory
m 19:19:56|main Getting work package...
m 19:19:...
- 1
-2
votes
1
answer
839
views
How to sent ETH from Parity command line
I was wondering if it is possible to send ETH using the parity command line, without opening the browser and going to the address 127.0.0.1:8080. I want to host my Parity instance on a headless ...
- 49
2
votes
0
answers
4k
views
How to send ERC20 Tokens to multiple addresses? [duplicate]
I've been 2 days trying to do it, with no success.
I need to send Tokens to 1300 addresses that participated in the Bounty/Airdrop and I can't send manually one by one, that would take a lot of time ...
- 51
1
vote
1
answer
352
views
How to invoke multiple oracaliszed queries from a single contract
I want to invoke 2 different orcalized queries from the same contract. I saw a few posts but none of the answer works. Is there any way we can do that? Here is my contract. I was expecting this ...
- 113
1
vote
1
answer
702
views
I sent ETH to my receiving contract address [closed]
I sent ETH to one of my receiving address which is contract address. But this receiving contract address was my personal trading wallet address. But, no transaction I'd has been received. When will I ...
6
votes
1
answer
934
views
Ethereum Merkle Patricia Trie and Hashes
In Ethereum, there's a hash of all of the 3 tries in each block.
Out of curiosity.
The docs state that the functionality is supposed to just provide a mapping between 160bit keys and values. I find ...
- 323
0
votes
1
answer
99
views
Smart contract development
I have read at many places
peoples require someone with an excellent experience to develop and
deploy a smart contract for ICO
Here my question is, what exactly smart contract is here?
Does ...
- 409
6
votes
2
answers
3k
views
Ethereum Merkle Patricia Trie (Extension node)
I do not have time to look through the source code right now. My questions is:
In Ethereum, when is the decision to replace part of a given path with an Extension-node made?
I suppose the sole idea ...
- 323
0
votes
1
answer
897
views
Share difficulty and hashrate
Can anybody explain relations or formulas between share difficulty, target and hashrate?
Thank you.
1
vote
0
answers
34
views
Calculating data amount being mined. Server
Does anyone know how to calculate hardware being used by mining activity on a blockchain? I'm curious what the equivalent hardware usage is in a blockchain. I'm looking for a formula of blockchain ...
- 11
-1
votes
2
answers
989
views
After leaving 1 hour my GPU mining ethereum via dwarfpool is it normal to be still at exactly zero?
Current understanding is that if you start mining a block on your own you might put your (single) machine in a very difficult situation in order to decrypt the block on it own and gain 5 ETH.
That is ...
0
votes
2
answers
212
views
ETC transaction doesn't reflect in myetherwallet -help
I just transfer ETC from my POLO account to the ledger nano s using
myetherwallet,
Ans something wired happend :
Here i dont see that i got anything
https://etherscan.io/address/...
- 3