All Questions

0
votes
2answers
26 views

Error generating new tokens in a private chain

pragma solidity ^0.4.25; // ERC20 Token Smart Contract contract MyToken { string public constant name = "MyToken"; string public constant symbol = "MYT"; uint8 public constant decimals = ...
0
votes
1answer
13 views

Node lags behind 100 blocks, states are finished syncing

I run my geth node with the following command: ./geth --cache 8192 --syncmode full It has been syncing for a long time, and it looks like it has finished syncing: > eth.syncing { currentBlock: ...
1
vote
2answers
24 views

How truffle selects the address with which it deploys a smart contract with and where does it gets it's private keys?

I am reading truffle tutorials for deployment smart contract to gauche, I've never deployed any smart contract to real network. Now when migrate (deploy) a smart contract I get these info: ...
0
votes
1answer
14 views

Associate event struct to user addresses

I have two contracts. One called User and other called Event pragma solidity ^0.4.24; contract User { mapping(uint=>address) addresses; uint addressRegistryCount; } pragma solidity ^...
2
votes
1answer
21 views

How to burn the token without burn method in contract

while time of contract development, management decided to don't burn any token and we will use our token as utility token for apps but now they have decided to burn unsold tokens after ICO. our ...
0
votes
0answers
5 views

using <DrizzleContext.Consumer> re-renders the component infinitely

I'm trying to build a simple dapp using drizzle-react's 'DrizzleContext'. This is how my index.js file looks like: import React from 'react'; import ReactDOM from 'react-dom'; import { Drizzle, ...
1
vote
1answer
30 views

Return a mapping in a getAll function

pragma solidity ^0.4.24; contract User { mapping(uint=>address) addresses; uint addressRegistryCount; function set(address userAddress) public { addresses[...
1
vote
2answers
14 views

How to install infura to a server runing ubuntu 16.04

Im setting up an exchange and came to the installation of ethereum using this document http://support.bitexchange.systems/support/articles/how-to-install-ethereum-in-your-server. The 'geth' command ...
1
vote
1answer
16 views

How to ERC721 token using external contract to msg.sender?

I have Caller and ERC721 contract just like this : contract SampleToken is ERC721MetadataMintable { string private name; string private symbol; constructor (address _creator, string _name,...
0
votes
1answer
14 views

How can I access a contract's fallback function via 'myContract.methods'?

Web3.js documentation says here that the methods of a smart contract are available through: The name: myContract.methods.myMethod The name with parameters: myContract.methods['myMethod(uint256)'] The ...
0
votes
0answers
22 views

Linux Geth Mining: Stuck at Commit New Mining Work in private blockchain Offline

System information Geth Version: 1.8.20-stable Go Version: go1.11.2 Operating System: linux GOPATH= GOROOT=/home/travis/.gimme/versions/go1.11.2.linux.amd64 Genesis.json { "config": { "chainId": ...
1
vote
1answer
28 views

In the Remix Web3 Provider IDE, how do you call a function in an ERC20 token contract from another contract without getting an estimateGas error?

I am building a very basic smart contract, 'CheckAllowance', on top of the 'FiatTokenV1' ERC20 token in the Remix Web3 Provider IDE. When I try to check an address's allowance in the 'FiatTokenV1' ...
0
votes
0answers
10 views

Using Private Blockchains/DLT (E.g., Quorum) for Cybersecurity purposes to forestall data exfiltration/data leakage through consensus mechanism [on hold]

I am keen to use Private Blockchains/DLT such as Quorum for cybersecurity intent namely to deter and forestall data exfiltration through consensus mechanisms, i.e., securing read operations on smart ...
1
vote
1answer
15 views

How to change all the ethereum blocks from C drive to D drive — question about the answer

I'm new here and have no idea if this is the right way to respond. So I duplicated the question a have a question about: I've done the things written in the answer on the original question and I ...
0
votes
1answer
15 views

Unable to use call.value to send the ether to another contract

Block Builder! I create a bank and client contracts, in order to reproduce DAO attack event. The client can deposit, but can not withdraw. I enclose the repo from Github here: https://github.com/...
0
votes
2answers
21 views

Can smart contract send tokens/eth if it doesn't have a send function?

Let's assume you just created 1,000 tokens at address 0x012345. You, the owner of 0x012345 sent by mistake all tokens and 1ETH to a smart contract with address 0x987654. This smart contract doesn't ...
0
votes
0answers
13 views

Array Compare function returns opcode error [on hold]

VMerror:invalid opcode Solidity code pragma solidity ^0.4.25; contract addition{ uint consensus=0; uint[] x; uint[] y; uint sum =0; uint sum1; uint sum2; uint length1; ...
2
votes
1answer
20 views

Burn the rest of the token after airdrop is complete

I have started to develop blockchain and learn solidity. I tried making a smart contract with the 200M supply, the creator only held 50M of the total supply and the rest was in the smart contract for ...
2
votes
1answer
13 views

Trying to understand why my test.js fails

I have a function that is not passing my tests in JS but the function works as expected in Remix. Can you help me contract.sol function test1 () public view returns(bool){ return(true); } ...
0
votes
1answer
14 views

Is there multiple chains of block in ethereum network?

Since blockchain is a chain of blocks, In ethereum, 1. is there only one chain of blocks 2. are there multiple chains of blocks.
0
votes
0answers
12 views

How can I create transaction via BlockCypher Ethereum API?(missing trie node)

I am created two ETH addresses, BUT I dont have any wei on it, if I will try create transaction, what response should I get, error that I dont have any wei or something like this {'error': 'Error ...
1
vote
1answer
24 views

Getting all past events in web3JS

I have seen similar questions here, but the answers didn't help so far. I have a JS function in a React component that should parse all the past events of the contract. The function is invoked in ...
0
votes
0answers
21 views

ERC-20 decimals issue

I'm using a simple crowdsale contract: pragma solidity >=0.4.22 <0.6.0; contract owned { address public owner; constructor() public { owner = msg.sender; } ...
1
vote
0answers
16 views

Processing gas cost on a sidechain

I am developing a sidechain that will store data and I want to evaluate the processing of this data in the ethereum network to get the cost in gas. I'm going to develop a smart contract that will ...
0
votes
0answers
8 views

How to control an ethOS rig miner remotely?

Apparently one of ethOS features is instruct rig to remote reboot and other settings remotely. How to control an ethOS rig miner remotely ? Apparently, I need to edit local.conf file. If so, how ...
0
votes
1answer
17 views

Wich version of solidity do I have to use in Quorum

If I want to use Quorum, in which Solidity version do I have to write my contracts?
0
votes
0answers
18 views

How to read data from external files in Quorum Blockchain?

I have a use case where we have implemented Quorum Blockchain using AWS. The smart contract was written in Solidity. Initially we randomized the valued by coding in Smart Contract however we now want ...
2
votes
2answers
27 views

Which version of solidity works web3js [on hold]

In what version of solidity do I have to write my smart contracts if I want to interact with Web3.js
0
votes
2answers
18 views

ERC721 Error: invalid number value arg=“_tokenId”, coderType=“uint256”, value=

MyERC721: pragma solidity ^0.5.0; import "openzeppelin-solidity/contracts/ownership/Ownable.sol"; import "openzeppelin-solidity/contracts/token/ERC721/ERC721Full.sol"; import "openzeppelin-solidity/...
0
votes
0answers
9 views

Struct Mapping: DeclarationError: Identifier not found or not unique for

Using openzepplin version 2.0.0 and solc version 0.5. I am writing an ERC721 token contract on truffle. Truffle compiles with no error on solc 0.4.23. I had to upgrade to 0.5 due to openzepplin ...
0
votes
1answer
12 views

How to send context from DrizzleContext.Provider to a Class Component / Class Container

I'm using the new Context API supported 'drizzle-react' library in my dapp. Can anyone please clarify how to receive the context sent from DrizzleContext.Provider into a "class" component? Check out ...
0
votes
0answers
16 views

Ethereum blockchain monitoring and contracts input data parsing

I am monitoring a particular addresses, that may be used as transactions' destination addresses in contracts' internal transactions. I should support monitoring of the sendMultiSig method (contract - ...
0
votes
0answers
8 views

What is the Ethereum equivalent of BIP37?

I’m looking for a library/standard for my spv wallet to learn about its incoming transactions. Do we have the Ethereum equivalent of BIP37?
0
votes
1answer
19 views

How does number of miners impact in processing the business logic(smart contract) in Blockchains

Does a number of validating devices/miners have an impact on processing business logic? If I understand correctly, as the number of validating devices increases, the time it takes to reach the ...
0
votes
0answers
14 views

Really slow syncing on mainnet with SSD disk and archive mode

I've set up a full Parity Ethereum node connected to the main network on a server with 2TB SSD, 4 CPUs and 8GB memory. I've set the pruning mode to archive since my application does a lot of state ...
0
votes
1answer
14 views

approve() and sendFrom()

Im trying to run the code below in a smart contract to use as an escrow. calling approve first and calling send from later does nothing to get the tokens into the smart contract, what am I missing ...
0
votes
0answers
20 views

is there anyother way to open ethereum wallet? [on hold]

I am working on ubuntu 18.04.1LTS. I have downloaded the zip file Ethereum-wallet-linux64.0-11-1.zip. The executable Ethereum wallet will not open.
0
votes
1answer
15 views

How to add True USD on Myrtherwallet [on hold]

i want to buy some true USD tokens, how should i add it on myetherwallet?
0
votes
1answer
21 views

Fallback function calls get reverted

I created a contract which mints tokens when the msg.value is higher or equal to the token(ticket) price. Unfortunately when I send a transaction to the contract fallback it gets reverted. It's my ...
1
vote
0answers
28 views

blockhash refactoring, if hashes are relative to latest block, are all stored in contract?

The blockhash refactoring EIP included in Constantinople expands the range of blocks that can be accessed with blockhash(). Besides the last 256 blocks, 256 multiples of 256^1, and 256 multiples of ...
0
votes
1answer
22 views

Which laws have to be followed for an ICO/STO in Europe? [on hold]

Which laws have to be followed for an Initial Coin Offering / Security Token Offering in Europe? P.s.: Don't worry, the purpose of this question is NOT to rely on the answers solely. Consultation of ...
0
votes
1answer
15 views

Unable to sign a message on geth Console

I have two accounts on my geth node . The geth node is syncing with the Ropsten testnet . I executed the following commands personal.unlockAccount(eth.accounts[1],'Test'); The result was true After ...
0
votes
0answers
23 views

Sending message on a transaction?

I want send a data on a transaction. _data is storing my message.. Here's my code: const Tx = require('ethereumjs-tx') const Web3 = require('web3') const web3 = new Web3('https://rinkeby.infura.io/v3/...
0
votes
1answer
28 views

Could not find “store” in either the context or props of “Connect(c)”. Either wrap the root component in a <Provider>

i'm trying to create a drizzle-react app which uses the new DrizzleContext component but running the following error in my 'localhost:3000': > Could not find "store" in either the context or ...
0
votes
0answers
20 views

2019 SPECS FOR RUNNING GETH FULL NODE

What are the specs for running an ethereum full node in Jan 2019? No fast flags as eth.blocknumber and some other methods needed. PLEASE NEED OFFICIAL ANSWER Thank you! I have a very powerful machine ...
0
votes
1answer
20 views

How to instantiate an array of struct inside a struct

Collection[] public collections; struct Book { string name; address writer; bytes32 proof; } struct Collection { Book[] books; address collectionCreator; } // Question: how to ...
0
votes
1answer
30 views

Could somebody explain me what is the difference of msg.sender, spender, from, to, owner in ERC20?

I read ERC20 solidity code below. https://github.com/OpenZeppelin/openzeppelin-solidity/blob/master/contracts/token/ERC20/ERC20.sol Then, I couldn't understand what the terms of msg.sender, spender, ...
0
votes
1answer
38 views

How can a peer request another peer to invoke a function from his private contract

I build a permissioned network using Quorum, I have a peerA which has a private smart contract, another peerB that cannot invoke functions of the smart contract as it is private So, can peerB send ...
0
votes
0answers
17 views

BOUGHT ETH at COIN MAMA did not know it be a SMART CONTRACT NEVER GOT IT AT WAVES CLIENT [on hold]

CAN I RECOVER IT SOME WAY with the HASH WAVES DONT SUPPORT SMART CONTRACTSAND THEY CANT GET IT TO MY WALLET I DID NOT KNOW COIN MAMA USED CONTRACTS FOR ETH PURCHASES
0
votes
0answers
8 views

Issue in understanding Crowsale in the ICO contract

I want to create a token and run an ICO but all this without the function of crowdsale and minting. It want it to be a token which has a strict initial suplly (exmpl 1M) and without the funtion of ...

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