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Difference between “decoded input” and “input” in Remix?

What is the difference between "decoded input" and "input" in the remix output? If these functions were to be called in an actual blockchain, would the "decoded input" be saved in a block, and thus ...
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0answers
5 views

Metamask Signing gives different signature than web3.js

I have successfully been using metamask to sign EIP712 data. I am currently trying to write truffle tests and need to replicate the signing process outside the browser. The issue I am facing is that ...
1
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1answer
4 views

Where is the Parity v2.5.11 web UI at?

This used to open the parity web UI for my local node, but now the browser it says it cannot connect, as if I just entered any other bogus port: http://127.0.0.1:8180/ I upgraded from Parity 1.7 to ...
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0answers
10 views

EIP-712 typed signature for arrays

I'm trying to generate a typed signature for an array in JavaScript based on EIP-712 and using eth-sig-util. My problem is that I need to sign an array. It says in the specification to use Type[] or ...
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0answers
11 views

recursive constructor via modifier?

I have just encountered several interesting Solidity contracts. Below is an simplified one where a modifier (Example(5)) decorated on the constructor seems to call that constructor recursively, which ...
1
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0answers
8 views

How many times has the Ethereum mining difficulty bomb been pushed back?

Ethereum has a built in mining difficulty bomb to force an upgrade. How many times have the difficulty bomb been pushed out? And by pushing out this mining bomb, doesn't this create more ETH into the ...
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0answers
21 views

Connecting robot to Ethereum Blockchain

I have a social robot (Pepper) and I would like to connect it to ethereum blockchain node. The robot support Python language. Thanks in advance for your helps.
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1answer
15 views

How dangerous is to use tx.origin to check if msg.sender is some address? (details below…)

Let's say: function transfer() public payable { require(tx.origin == 0xb2930B35844a230f00E51431aCAe96Fe543a0347); msg.sender.call.value(1 ether)(); } Ignore the address above I just copied it ...
-2
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0answers
16 views

Transaction ran out of gas after adding gas and nonce in signedtx

When i called method from my test erc20 contract on private dev chain. it always gives me error that Transaction ran out of gas. but in parity event list it shows me that event occurred. i get ...
2
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1answer
15 views

Blockchain overhead - general question

I was reviewing the blockchain technology the other day, Maybe this is not the right place or maybe I should rephrase my question but.. Blockchain is peer to peer, every peer stores the data Data is ...
1
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0answers
9 views

Calculated blockhash of PoA block mismatches with actual blockhash returned by RPC

I set up a Demo PoA chain using Parity Etheruem. I sent some transactions to it and it started producing blocks. A block on my demo PoA chain was generated with block hash ...
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0answers
15 views

Invalid implicit conversion from int_const 0 to address requested [duplicate]

Invalid type for argument in a function call. Invalid implicit conversion from int_const 0 to address requested.
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1answer
18 views

How to check when erc20 token was received in certain address

i am hosting a node and fully sync it. how i can call its api endpoints to figure out when DGX is received in certain wallet addresses.
0
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1answer
11 views

How to store token number with their holders?

I am actually looking towards cost reasonable design idea where I can know that which token number belongs to which wallet address. let's say addressA bought first five tokens, so token no 1,2,3,4,5 ...
1
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1answer
12 views

Watching for events

How come sometimes events show up on block explorers in hex and sometimes to you can see the actual string name of the event in the logs. I ask because my event watchers on my front end only pick up ...
1
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0answers
20 views

Delegate transaction signature

What's the most efficient and trust-less way to sign a transaction through a middle-ware? Thanks for your help.
-1
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0answers
8 views

autocall send recieve tokens (what is best way )

my need : autocall for m-reson happen in my contract to send ETH to m_address of binance sell it there and then send back usdt to contract is there a way to do this in decentrlized way ? ...
1
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1answer
18 views

Cannot verify Solidity contract code on etherscan.io

I am unable to verify the contract below on Etherscan. No errors in Remix. I tried all of the solutions recommended in answers to similar questions, which were: Remove the ^ in pragma Compile ...
2
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0answers
16 views

How to calculate vanity address using C?

I have a curiosity about tacking on zeroes to strings, and Ethereum addresses are no exception. I wrote my own python program, and it was too slow. I wrote the program at https://pastebin.com/hTFGiKzR ...
1
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0answers
17 views

Address to create a contract

This query is for informational purposes, with something that has had me in doubt all night. I am trying to send a self-signed transaction for the creation of a contract My Tx transaction to send is ...
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0answers
3 views

input field is not getting displayed by using ContractForm

<DrizzleProvider options={drizzleOptions}> <LoadingContainer> <div> <h1>Welcome Doctor</h1> ...
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0answers
23 views

How can execute function that send ether in geth console?

I want to execute the send function that sends ether from the sender to the receiver, the code is as shown below. contract Sender { function send(address _receiver , uint amount) public ...
0
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2answers
23 views

How to get new transactions by addresses?

I have an array of addresses on my server which I need to track. What method should I use to do that via websockets? I’m new to eth and cryptocurrency at all, and I don’t understand “blocks”, “gas ...
0
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1answer
18 views

Send transaction with locked contract -> Error: insufficient funds for gas * price + value

I'm trying to send a transaction for a token with a locked contract. I'm doing this to find out when this contract will be open. So I'm expecting to get some kind of error like "ERC-20 Token Transfer ...
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0answers
10 views

Some of the new Ethereum Txn hashes are not showing on any blockchain explorer

I have my own node setup using parity for ethereum. Everything was going perfect. But from today , means right after Ethereum hard forked into their improved version of "Istanbul" at block 9069000 ...
1
vote
1answer
12 views

how to create Function Selector (Method IDs)

As stated in ABI specs that 0xcdcd77c0: the Method ID. This is derived as the first 4 bytes of the Keccak hash of the ASCII form of the signature baz(uint32,bool). So, I have to create method IDs (...
0
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1answer
17 views

Dispute in smart contartcs [closed]

i don't have enough knowladge of contracts. any one have a good article about What is arbitration and dispute in smart contracts.can you please help.
0
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1answer
25 views

Is it possible that a contract address is same as a external address?

For example i create a contract first, and then i generate a private key that map to the contract address. I know that is hard to achieve but is it possible theoretically?
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0answers
23 views

Retrieving the first and latest transaction date of a contract

Etherscan offers a time series of ethereum transaction of a contract address. Is there a way to retrieve this data? For example the duration mentioned here https://etherscan.io/address/...
0
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1answer
10 views

Passing array of struct as parameter: Only libraries are allowed to use the mapping type in public or external functions

I am trying to push multiple items to the array of structs in the contract. Couldn't find a clear answer if it is possible to pass an array of struct as a parameter. Apparently I can't but I get a ...
0
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0answers
16 views

TypeError: CreateListFromArrayLike called on non-object

I have this contract and deployed it to my local client (ganache gui) and its abi.json file (of solc compiler generated). The third file is param.txt which contains encoded functions with arguments ...
0
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0answers
8 views

Is there a way to check if a hosted node is running on the new fork?

I am hosting Rinkeby node using geth v1.97. However, I was wondering if there is a command or way to check whether it is running on the new fork or not.
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0answers
17 views

How to get BNB ERC-20 address from Binance API?

I was going trying to use the binance API for getting the token address for the BNB ERC-20 token. But using just BNB as the asset name returns the Binance Chain address for the BNB token. I have ...
0
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1answer
15 views

How do I install Go-ethereum and solidity on Debian10

I am using debain on wsl and I want to install ethereum and solidity for blockchain development but I am not able to find an exact way to do it.
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1answer
32 views

Using await with web3 function calls

I have just implemented a tweak to make my asynchronous call run sequentially, however it is messy solution. I have got the following code: async function myClick() { calculateAmounts(); ...
0
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0answers
9 views

local testnet mining error

my genesis.json file { "config": { "chainId": 271, "homesteadBlock": 0, "eip155Block": 0, "eip158Block": 0 }, "nonce": "0x0000000000000042", "...
0
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1answer
20 views

I´m new to Ethereum and Solidity, ¿can anyone help me?. Thank you!

I have to: Write a Contract Constructor that will store the addresses at each of the member variables you declared in the previous stage. The arbiter and beneficiary will be arguments to the ...
0
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0answers
8 views

Truffle to Ropsten Testnet Deployment Issue: No migration

I am trying to deploy my contract on Ropsten test network through Truffle Framework. I use the command truffle migrate --network ropsten. Following is my truffle-config.js: const HDWalletProvider = ...
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2answers
41 views

multisend ERC20 tokens

I have main address: const fromAddress There is also an array of addresses and their keys:foreth/keys I need to send all erc20 tokens from: foreth array to the: fromAddress Tokens are sent only ...
0
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0answers
9 views

Is there same offical article about how Ethereum Gas Tracker calcluate price?

Is there same offical article about the approach how ethscan.io's gas tracker get price and time? I think it calculate form the transaction hisotry in last 1000 block.But no article or code can be ...
1
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1answer
14 views

Transfer WETH from myetherwallet to metamask wallet

I converted some of my ETH to WETH already, on my hardware wallet. H/w wallet was conected to myetherwallet, and I can see my WETH there under tokens panel. I also created a metamask wallet and I am ...
0
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1answer
18 views

How to store data on ethereum blockchain WITHOUT IPFS

Hi guys ^^ i want to store PDF file on ethereum blockchain without use of IPFS. I want to do it because i have my own private network where this data will be only stored. That's why i want to store it ...
2
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1answer
14 views

What is the Muir Glacier hardfork?

What is the Muir Glacier hardfork on the Ethereum mainnet?
2
votes
1answer
13 views

Check emitted event with BN

I'm currently testing events that include numeric values: const level = new BN(1); truffleAssert.eventEmitted(tx, 'EventName', {level}); As you can see, the level variable is a BN, and holds the ...
1
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0answers
13 views

UNGAS and why was GAS made available to programming smart contracts?

Hardforks, such as Istanbul, have illustrated the best practice that smart contracts should not make any assumptions about gas. Gas costs have, can, and will change, for example: Is transfer() still ...
0
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0answers
11 views

Compiling Old Version Contracts , gives ParserError: Expected pragma, import directive or contract/interface/library definition

Ihave to compile some old contracts (having solidity pragma is <0.5. For this purpose, I have just copy and paste this contract from Etehrscan and save with its name in contracts folder. Install ...
0
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1answer
23 views

private key should be a Buffer

I need to check the balance of several addresses for the presence of erc20 tokens, if the balance is not empty, send eth there and forward this balance to the resulting address. But in the end, I get ...
0
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0answers
15 views

Gas limit per block - Increasing or Decreasing the value of Gas limit in Go-Ethereum Source Code

My question is that is it possible to modify the value of Gas limit per block in go-ethereum source code. If yes, which part of GasLimit value could be affected on the Gaslimit per block in source ...
1
vote
1answer
15 views

can a smart contract autonomously hold erc20 tokens or ETH?

I want to make a simple smart contract, but I don't know if smart contracts are capable of what I desire. Please tell me if they are: a user can send ETH (or any ERC20 token) to the smart contract ...
1
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1answer
23 views

Should I stop the geth node during hard-fork?

As the countdown on https://ethernodes.org/istanbul, should I need to stop my geth node before hard-fork? Or I could continue to syncing during hard-fork. Thanks alot.

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