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6 views

How do I startup geth to allow incoming work from an ASIC miner?

Github only shows options for GPU and CPU mining. I would like to point an ASIC at my geth node. Does anyone know how that's done? Other pools will accept connections such as: stratum+tcp://eth.pool....
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1answer
28 views

abi.decode with pragma experimental ABIEncoderV2 reverts with nested array

I have a function with a parameter of bytes calldata that needs to be decoded to a struct, but the call reverts in assembly. I believe the issue has something to do with the nested array. I have ...
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0answers
21 views

How to Initialize two items with item 1 and 2 which is an array

I was given this assignment to initialize an array with 2 items but when I initialized them i had an error that said "invalid implicit conversion from int const_1 to uint256[]memory req". ...
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0answers
29 views

Cannot read property 'name' of undefined

const config = require('../truffle-config.js'); const token_parameters = require('../token_parameters.json'); const ExampleToken = artifacts.require('ExampleToken'); module.exports = function(...
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0answers
14 views

Getting wrong nonce when trying to send transaction

Im using opencv in ganache in this app to send an ethereum transaction In my app im getting the transaction that i send like that nonce = web3.eth.getTransactionCount(account_1) tx = { 'nonce': nonce,...
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0answers
16 views

Duplicate events from get_new_entries using web3.py

I'm struggling to understand how to properly poll events emitted from contracts. The provider I'm using is Infura. My code boils down to the following: filter = target_event.createFilter(fromBlock='...
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0answers
23 views

Can string be changed to equivalent bytes and bytes32 in solidity?

I was wondering if it is possible to convert a string to a bytes32 or bytes in solidity like this, I want an input in string and require an equivalent bytes32 and bytes both. input string = "...
0
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1answer
42 views

How to verify transactions on ethereum blockchain?

I have a smart contract deployed in which there is a variable A whose value is updated through a public function fun_update(). I want to get all the addresses which updated that variable A through the ...
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0answers
12 views

Geth network stopped mining

On my POA network there are 5 nodes/miners but suddenly all nodes stopped mining and giving this in console "INFO [09-05|08:50:16.267] Looking for peers peercount=4 tried=4 static=0". We ...
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0answers
7 views

How do lightweight clients use CHT?

In the description of the LES protocol Canonical Hash Trie (CHT) structures are used by LES for quick initial syncing and secure on-demand retrieval of canonical hash mappings, block headers and ...
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2answers
35 views

ERC1155 Validation Error code: -32000

I am using web3py to make a transaction. But I am getting validation error: {'message': 'VM Exception while processing transaction: revert Need operator approval for 3rd party transfers.', 'code': -...
1
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2answers
36 views

Unable to upgrade Truffle

I am trying to update Truffle on Ubuntu 18.04. I currently have version 5.1.33 of Truffle installed on my system. u/lc2530hz:~$ truffle version You can improve web3's peformance when running Node.js ...
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2answers
194 views

Gas refunds via “Self-destruct” prior to a revert()

In a transaction that eventually calls revert(), if prior to the revert we have SELFDESTRUCT some contracts and thus received a gas refund, does the gas refund also get reverted?
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0answers
17 views

Out of stack DUP2 1/1024 when adding string to parameter

The below function was working fine until I added a string parameter and saved the string to a mapping. Now when I call it it fails with an 'out of stack' exception. Is there something I'm doing wrong ...
1
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0answers
14 views

Rust: Need both events when a transaction is sent and when is confirmed

Rust. For a method send() of a smart contract I need to process both events when the transaction is sent (and generates txhash) and when it is confirmed. From https://docs.rs/ethcontract/0.7.2/...
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0answers
26 views

Rock, paper, scissors and Secrether.io

I have thought of a RPS game using secrether.io: playerA hashes keccak256(move+11charsRandomData) as hash and sends it to RPS smart contract. RPS creates a transaction to Secrether Smart Contract - ...
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0answers
26 views

Extending deployed contract in solidity

I need to deploy a lot of typical contracts with identical functionality. Is there a way for extending the already deployed contract in solidity? I hope to make a single big contract with main ...
1
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0answers
32 views

Huge gas cost for deleting an element of a map

As you can see with the code below the last person to call claimAuction cleans up the AuctionProposal but has to pay 383729 gas instead of 73846 for that cleanup, a 519% increase! My question is ...
0
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1answer
35 views

“Dropped & Replaced” tx - what should I do?

I requested a USDT withdrawal from Bilaxy exchange to my Binance USDT (ERC20) account. However, on etherscan, the transaction shows as "Dropped & Replaced". Do you guys think I shhould I ...
0
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1answer
27 views

Create map of existing objects in mint function for a smart contract

I'm really new to solidity and there is still alot I dont fully get. I have created this smart contract. I am getting an error while performing a test stating that the id to be set by the push cant be ...
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0answers
10 views

Adding proxy behind enode geth ethereum private network(Failed RLPx handshake)

I am trying to configure ngnix proxy behind geth. I have assinged a dns name to proxy. If I call xyz.com--it will internally redirect to IP:8000(in which JSON RPC is running) This part is working fine....
0
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1answer
34 views

Sweeping ETH from a 2 year old paper wallet, help?

I have a paper wallet from an ETH atm from 2 years ago. I am trying to sweep the funds onto a digital wallet. I have used multiple ETH wallet apps on my phone but none of them were able to recognize ...
0
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0answers
16 views

Check all failed transactions in last 100 blocks

How do I get all the failed transactions in last 100 blocks using etherscan or some other service? Also the reason for failure and gas involved in the transaction Checked few similar questions that ...
0
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1answer
18 views

What are some real world use cases for state channels?

Are there any state channel implementations being used today, or in development? (Not including payment channels) I'm interested in practical use cases rather than theoretical examples like playing ...
0
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1answer
17 views

I accidentally sent a BPT token to a token contract. Can I get it back?

Instead of transferring my BPT token to my wallet, I accidentally sent it to the contract itself. I sent 99,546.988023218400325838 BPT to the address 0x471eb7dcf6647abaf838a5aad94940ce6932198c The ...
2
votes
0answers
8 views

How do I automatically verify my contracts on etherscan using brownie?

I discovered truffle has truffle-plugin-verify that help you verify your contracts on etherscan. I wonder if similar functionality can be done with brownie ?
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0answers
20 views

What is the difference in the two mapping structures

Is the below mapping structure a legit way to create a restricted mapping, or is the latter best practice? mapping(address => SomeStruct)[5] private structs; and mapping(address => mapping(...
0
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1answer
28 views

Trouble using delegatecall to pass msg.sender to another contract

I'm trying to mint an NFT token in contract B by calling a method on contract A, but I want msg.sender (in contract B) to be the address that calls the function on A, not contract A's address. I ...
1
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2answers
19 views

At which (average) rate will block numbers increase with ETH 2.0?

Is the block number increase going to be more frequent than it is now ? The reason I am asking is because some smart contracts I am developing depend on the block number increase, so if this changes, ...
0
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1answer
38 views

Fees are too Damn High to send $20 worth of USDC. How can one minimize these fees?

It's 2020 September 3. Fees to send 20 USDC to someone is about $10-15 worth of gas fees. How can I minimize the gas fees when using metamask? And is it true that if I set the gas fee too low, I would ...
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0answers
9 views

Send from Drizzle useCacheSend hook sends trasactions twice

I'm following the old documentation about hooks and I'm getting a problem at sending transactions: every transaction is sent twice, why? The next is the current core: <form onSubmit={...
0
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1answer
19 views

Accessing dynamic variable name - external contract

Contract A wants to call an external contract B/C/D/E/F but the variable name is different within each contract B/C/D/E/F, and contract A does not know the variable name for B/C/D/E/F at the start. ---...
1
vote
1answer
69 views

How to get contract object using ABI json and address with web3j?

I worked with web3js(JavaScript) and used web3.eth.Contract with 2 params (json, address) and successfully got contract object. Now I started to work with web3j(Java) and don`t understand how I have ...
0
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0answers
12 views

Listen to contract creations on web3

Is it possible to listen to contract creations on web3? For example someone deploys a smart contract on the ethereum chain. Is there a method in web3 where I can listen to such an event?
0
votes
1answer
11 views

address of deployed RoleManagement contract on Volta

I'm trying to set up my own Origin framework and was wondering if it made sense to reuse the existing RoleManagement contract on the volta network
1
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0answers
17 views

web3 only works with metamask but no mobile metamask or trustwallet etc

i stripped down to the bare minimum to interact with a contract with metamask it works nice, i can call/transact nicely with only minimum of html/js but on mobile metamask or trustwallet it simply ...
0
votes
1answer
17 views

Etherscan Yellow Exclamation Sign - Compiler Specific Version Warning

I just noticed that my contract 0xa150Db9b1Fa65b44799d4dD949D922c0a33Ee606 has the warning on Etherscan (yellow exclamation). This is in the Contract section and the contract has been successfully ...
0
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0answers
7 views

Why I cannot get any updated smart contracts from etherscan after craweling while etherscan has supportted to upload proxy contract mark already?

Etherscan supports proxy contracts associated with its implementation contracts https://medium.com/etherscan-blog/and-finally-proxy-contract-support-on-etherscan-693e3da0714b since 2018. However, ...
0
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0answers
28 views

TypeError: Cannot read property '0' of undefined AND TypeError: eventAdded.watch is not a function

I'm currently trying to test run source code from GitHub based on a 2018 tutorial where solidity was using version 0.5.16. I'm currently using truffle v4.1.14. Appreciate any help. Thanks! In the ...
0
votes
1answer
17 views

TypeError: “send” and “transfer” are only available for objects of type “address payable”, not “address”

I'm currently trying to test run source code from GitHub based on a 2018 tutorial where solidity was using version 0.5.16. I'm currently using truffle v4.1.14. I understand that there was an update ...
1
vote
1answer
19 views

Does successful mining require the block's transactions in advance?

Typically a miner decides which transactions go inside a block. But does this have to be so? Is the actual mining process just a process to find the right nonce regardless of block contents or does it ...
2
votes
1answer
19 views

Am I locked to one solc version for upgradeable smart contracts?

I want to use delegatecall to make my contracts upgradeable. Is it true that variable layout may break if I change the solc version and therefore I should use the same Solidity version for all future ...
2
votes
1answer
97 views

i am new to this, can someone steal my erc20 token with the Function approve()

I have been using yield Farming (YFValue) and I noticed when I accept the contract via MetaMask. I set faming 500 USDT but in the contract the input was: Function: approve(address _spender, uint256 ...
0
votes
0answers
19 views

Node not syncing on Private Blockchain

Node 1 is mining but Node 2 is not syncing Running admin.peers on Node 1 gives: Running admin.peers on Node 2 gives: Both Nodes are using same genesis block When starting console on Node 2 I used --...
0
votes
1answer
137 views

Transaction dropped and replaced but still shows as pending in etherscan

I canceled a transaction by sending another 0 ETH transaction to myself customizing the nonce in Metamask. Now the canceled transaction shows as "dropped & replaced" in etherscan, but it'...
0
votes
1answer
32 views

TypeError: Operator >= not compatible with types bytes1 and int_const 37

pragma solidity ^0.5.16; library EmailRegex { struct State { bool accepts; function (byte) internal pure returns (uint) func; } function state(uint id) internal pure returns (State ...
0
votes
1answer
22 views

How is transferFrom secure?

function transferFrom(address sender, address recipient, uint256 amount) public virtual override returns (bool) { _transfer(sender, recipient, amount); _approve(sender, _msgSender(), ...
0
votes
0answers
9 views

“exceeds block gas limit” on partially synced geth

I am trying to send eth when my geth node is not fully synced (it's very, very slow) { currentBlock: 10683052, highestBlock: 10780597, knownStates: 57935524, pulledStates: 57929853, ...
1
vote
0answers
8 views

Suspicious md5sum of /usr/bin/geth

I want to sanity check my geth installation before unlocking my wallet. My geth version on Ubuntu is Geth Version: 1.9.18-stable Git Commit: f5382591874220287de253bfc08b10afd5244927 Architecture: ...
1
vote
1answer
29 views

How to get balance of an address using web3js

Here is a very simple code that i am using :- let web3 = new Web3(new Web3.providers.HttpProvider("https://ropsten.infura.io/v3/XXXXX")); var balance; web3.eth.getBalance("...

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