All Questions
611 questions
0
votes
1
answer
158
views
How to use web3 to send ETH from wallet A to wallet B through an intermediary Smart Contract?
I want to send eth from 1 wallet address A to wallet B address but through an intermediary Smart contract, what should I do? I don't know how to solve that problem yet.
EX: https://bscscan.com/tx/...
0
votes
1
answer
255
views
cant go make a local host account
i had a local host 8545 account and accidentally deleted it but i have no idea how to get it back. and it just keeps saying Could not fetch chain ID. Is your RPC URL correct? and im just on a pc
0
votes
2
answers
700
views
I get an error whenever I try to deploy on BSC testnet. It only works on the ETH mainnet. The source I am using is on BSC
I cant deploy this source code myself on BSC even though the creator can, I can only deploy it onto the ETH testnet, not BSC.
Here is the original contract: https://bscscan.com/address/...
2
votes
1
answer
932
views
Send transaction with Brownie without confirmation wait
Is there is a way in Brownie to send a transaction without waiting for confirmation, like an async way?
- 158
0
votes
0
answers
888
views
How to send BNB (or other networks) with web3 on a dapp?
So, I tried the many examples found around but I never manage to get it working.
I have this snippet:
async function pay(cost) {
code = 0
message = "Please approve the tx"
...
- 123
0
votes
2
answers
1k
views
Create a MAX SUPPLY to Mint ERC20
I want to create an ERC20 on Solidity.
I want 1000 TOKENS of MAX SUPPLY (Like the 21m of bitcoin).
PERSON A: Mint to his wallet 700 Tokens. (Thats okey)
Only 300 Tokens are available.
PERSON B: Mint ...
- 25
0
votes
1
answer
3k
views
How I send tether token on metamask?
I have 1053 USDT and 0.0028 ETH in my metamask wallet.
I want to send 1000 USDT to other address but I faced "Insufficient funds." for ETH.
So, I think I can swap 53 USDT to ETH. But faced ...
- 86
0
votes
1
answer
493
views
Forgot password of eth keystore v3 mist wallet keystore!
I have my ethereum keystore v3 , it is mist keystore file , but it also may login from myetherwallet site,I forgot password to it,I tried lexansoft,but all alphabet so long to try,I will write my hash ...
- 11
1
vote
1
answer
2k
views
Why am I getting "Error: unknown account" when trying to send ETH using eth.sendTransaction?
I have an ETH testnet set up using this docker-compose.yml file.
When I try to send 1 wei from the "buffer" account 0x411167FeFecAD12Da17F9063143706C39528aa28 to the test account ...
user64747
1
vote
0
answers
774
views
Why don't we have an EVM integration library written in C++?
We have web3.js for JavaScript, web3j for Java and NEthereum for Unity/.NET.
I want to develop with Unreal Engine (C++) a game that runs on Polygon, but there's no integration library in C++.
Should I ...
- 11
0
votes
0
answers
35
views
Old eth network accounts do not appear after reinstalling metamask
I have a serious problem.
I switched from Note and in the new Note I restored Metamask using my phrases.
The installation worked.
Inside the Metamask of the old note I had the ETH network with two ...
- 1
0
votes
1
answer
30
views
I transfered ERC-20 token to the wrong Efinity address [duplicate]
I transfered ERC-20 token to the wrong Efinity(NFT blockchain on Polkadot) address,how to get it back? Someone plz let me know
1
vote
1
answer
893
views
Is there Blocks Pruning in ethereum clients specialy geth? (and other questions)
Is there Blocks pruning in ethereum clients such as geth and how does that work?
by pruning I meant, does the blocks information whether stored in DB like in cpp-ethereum are deleted if the ...
- 173
1
vote
0
answers
51
views
questions on block (and header) storage in ethereum, how is it stored along with tries?
I understand that ethereum uses Trie to track the state, transactions, receipts. and each trie has key-value pair that is stored in the database.
Each blockheader also has the root has of stateRoot, ...
- 173
2
votes
0
answers
62
views
Why does Ethereum use RLPx over TLS?
Ethereum encrypts data sent between peers. What are the reasons for implementing RLPx over TLS?
- 21
2
votes
0
answers
112
views
What is Ethereum's protocol stack regarding cryptography?
Resource 1 says that “There is no encryption as part of the Ethereum protocol—all messages that are sent as part of the operation of the Ethereum network can (necessarily) be read by everyone. As such,...
- 21
0
votes
1
answer
2k
views
How get private key from eth address public key/address
By mistake I send "TRU" erc20 token in a ether address and can't access it now. I have only eth address and public key of this address. How to get private key from eth address or using ...
0
votes
1
answer
229
views
How to securely send a message
I was wondering that can I encrypt a string, send it to a smart contract, for that to be decrypted only by some address's private key?
e.g "Hello" to be encrypted in a way that it would be ...
- 67
1
vote
0
answers
904
views
Getting nonce too high on RPC debug_traceTransaction call
i am trying to get the transaction trace (similar to the one found as Geth trace_2 on etherscan) and to do so i try to use the debug_traceTransaction but each time with any transaction hash i am ...
- 3,058
1
vote
0
answers
123
views
Experimental data on transaction propagation time
Does anyone have empirical data on how long does it take to propogate a transaction thought out most of blockchain?
I know we can speculate on how long it would take (like here). But I am interested ...
- 123
1
vote
1
answer
322
views
Not able to use --testnet flag on geth windows
I have a problem where if put
geth --testnet removedb
it says
flag provided but not defined: -testnet
Im on windows 10 x64. Thanks in advance!
- 21
2
votes
1
answer
756
views
Geth Reverse Proxy "Invalid Host Specified"
I am getting 403 "invalid host specified"
Running geth this way:
docker run --rm -p 8547:8547 -p 30303:30303 --name=geth -dti -v /data/geth:/data ethereum-node --datadir=/data --http --http....
- 161
1
vote
0
answers
257
views
Listening to smart contract events RPC, using web3, on aleth node
bakcground,
I am working on an ethereum based fork of cpp-ethereum/aleth node and not using the official golang client (geth), unfortunately from what I read, websocket support has been 'ditched' in ...
- 21
4
votes
1
answer
4k
views
Web3: Get token address from pair address
I am studying all listed pairs on Pancakeswap. I get the pair address from
PCS_FACTORY_ADDRESS="0xca143ce32fe78f1f7019d7d551a6402fc5350c73"
PCS_FACTORY_ADDRESS = Web3.toChecksumAddress(...
- 41
0
votes
0
answers
12
views
ETH sent to contract address, how to get it back? [duplicate]
Instead of transferring my ETH token to my wallet, I accidentally sent it to some contract address, this one: 0xE592427A0AEce92De3Edee1F18E0157C05861564.
Is there any way to get my ETH back?
0
votes
1
answer
628
views
How To Verify A Coin Without Original Contract Source Code?
We are new to crypto. A while ago we created a coin (3DOM coin) with 14,000,000,000 units and stored them in our wallet on myetherwallet.com. We would like to deploy the token now but we do not have ...
2
votes
0
answers
164
views
Running a SPV wallet on Arduino/ESP32?
I want my ESP32 to make transactions and check for the details of blockchain using a secure method. Actually, I want to use make calls to the blockchain instead of relying on a single node. In my ...
- 683
1
vote
1
answer
243
views
Compilation Error while using ChainLink
I am using Remix IDE for my smart contract development. I am using the following import line
import "https://github.com/smartcontractkit/chainlink/blob/develop/evm-contracts/src/v0.6/...
- 13
0
votes
1
answer
133
views
I tried to send eth from Metamask (in balancer) but transfer is looking failed but I loss my eth(90$ around) What I should do?
I tried to send eth from Metamask but transfer is looking failed but I loss my eth(90$ around) What I should do?
0
votes
1
answer
48
views
RPC connection fails
I launched my geth with those parameters :
sudo geth --syncmode "light" --cache=2048 --datadir /mnt/ssd/ethereum --pprof.addr 0.0.0.0 --pprof
It's running on a ubuntu server 20 on a ...
- 181
1
vote
1
answer
434
views
Simple way to send gasless Transactions
I was wondering if there is a way for a user to pay transaction fees for another user, meaning user A sign the transaction and user B send it to the network and pays the gas fees.
I found a solution ...
- 13
0
votes
0
answers
743
views
Connecting external server to Ethereum node via RPC failed "bind: cannot assign requested address"
I am trying to connect an external server to my Ethereum node. Considering I don't want to use --rpcaddr 0.0.0.0 (which it works)for security reasons, I am using the following command to start geth:
...
- 39
2
votes
1
answer
920
views
405 Method Not Allowed with websocket geth RPC
curl -i -N -H "Connection: Upgrade" -H "Upgrade: websocket" -H "Host: XXXXXXX" -H "Origin: https://XXXXXXX/" -H "Content-Type: application/json" -X ...
- 162
0
votes
1
answer
42
views
pending transaction on eth blockchain
i still waiting from 4h for my transaction. I know de gwei is low but what you think it will be processed.
0xb69c181d38bcd157d07a623b5c1b620e6694644626bc1ed48e984ed089933e86
- 1
1
vote
0
answers
36
views
Ethereum NFT options
I am looking at producing a set of NFT's that are a set of 100, the item does not have an image, but is a token to run through an algorithm, I want them to be limited whole NFT's, not ERC-20s.
I am ...
0
votes
1
answer
175
views
Is their any change to move a wallet from an bnb blockchain to an ethereum blockchain?
I transferred some ethereum to my bnb wallet. Later I found out that this bnb wallet is not on the ethereum platform.
So I send an amount of ETH to an address similar to the address of the bnb wallet (...
- 1
0
votes
1
answer
95
views
A silly question about web3.eth.sign
I'm a beginner and I need to sign the data with metamask，Find the document https://learnblockchain.cn/docs/web3js-0.2x/web3.eth.html#sign
then In the browser's debug desk ，i try run
web3.eth.sign('...
- 1
0
votes
1
answer
236
views
Is it possible to charge extra ETH fee for token transfers? [closed]
Is it possible to accumulate fee amount deducted from transfer transactions in a different address in smart contracts?
Person A transfers tokens to Person B. Let's say the transaction fee is 0.1 ETH, ...
- 1
0
votes
1
answer
42
views
any 3rd party service that can get all transaction?
3rd party service recommended
have any 3rd party service that can get all transaction of address?
because from my research the web3 cant get the full transaction by account.
- 1
0
votes
0
answers
523
views
Internal Transactions - How to find out the address of the contract that is calling?
i have been Googling for this answer, but i haven`t succeeded.
The scenario is the following: I have two contracts interacting with each other, and I want to make sure that they only respond to each ...
- 29
1
vote
1
answer
984
views
The security of JSON-RPC
I currently use web3 and geth to develop dapps, and we know that web3 interacts with geth through json rpc. If we want to unlock an account through dapp, we need to enter the password in the dapp, and ...
- 437
2
votes
1
answer
5k
views
message: 'invalid argument 0: json: cannot unmarshal hex string without 0x prefix into Go struct field SendTxArgs.value of type *hexutil.Big'
I am using a JSON RPC request and source code is as follows:
var options ={
url: "http://127.0.0.1:8545",
method: "POST",
headers: {"Content-Type":"...
- 21
2
votes
0
answers
58
views
Encoding and signing transaction with aleth client [closed]
I am learning aleth client. I want to do two simple steps:
encode json to rlp with ./rlp create [...]
sign this rlp with ./aleth-key sign <ma_rlp>
And I am getting errors in ./aleth-key sign &...
- 101
1
vote
0
answers
102
views
creating and signing transaction
I am looking a way to create signed transaction using c++ libs from aleth. I have this transaction:
{
from: "0025defd0f341b7f673f84b81c8416d58df29045",
to: "...
- 101
7
votes
3
answers
3k
views
Is there any c++ library for signing transactions?
I am working on light wallet in c++, and I am looking for a c++ library for signing transactions. I mean something where i will pass transaction and private key and it will return signed transaction ...
- 101
1
vote
0
answers
483
views
Understanding eth_estimateGas with regards to gas price, and current mempool
Does anyone have a detailed understanding of how eth_estimateGas works with regards to gasPrice and the current mempool state?
I have historically seen some really odd behavior when using ...
- 640
0
votes
0
answers
43
views
Using two key for displaying data from contract
i can't found any idea how to get data with two keys. One key "address", second key is "IsCollect"
My mapping:
mapping(address => Player) public users;
struct table:
...
- 1
-2
votes
1
answer
786
views
Datetime in solidity [closed]
how can i get date time in solidity like that: 14/10/2020 20:50. I don't want 8:50 PM.
I get in timestamp but timestamp not possible convert because I have wrong timestamp.
- 31
1
vote
0
answers
393
views
Properly Exposing Geth RPC in 2020
With the default allowed ["net", "web3", "eth"], I want to expose Geth 1.9.21-stable RPC to another machine.
In config.html I set HTTPVirtualHosts = ["*"].
The ...
- 232
1
vote
0
answers
36
views
Generating blocks without mining,
I have private test network, and I need to simulate forks. Is any possibility to immediately set number block fork-1 (in PoA or any other protocol) ? If yes, what is the easiest way to do it ??
- 11