All Questions
18 questions
0
votes
0
answers
97
views
Recreate transaction log in solidity code
I have this log and i want to code a solidity contract/function that would do the same.
What i understand reading this transaction is that WBNB contract (0xbb4cdb9cbd36b01bd1cbaebf2de08d9173bc095c) is ...
- 13
3
votes
1
answer
2k
views
Find a Function Call Across All Contract Transactions
Is it possible to search for a particular function call across all transactions of a smart contract?
I'm doing due diligence on 1inch's smart contract in order to see if renounceOwnership was called ...
- 253
3
votes
1
answer
532
views
When a contract calls other contracts, is it an atomic operation?
If a contract calls several external methods of other contract(s), is it as a whole one atomic transaction (reverted as a whole if an exception happens)?
- 1,854
1
vote
1
answer
205
views
Can you activate Contract Functions just by receiving Ether alone?
Noob Question here. I have a Dapp that has no actual need of a web interface. What is the best way to activate functions if someone did something as simple as send Ether to an address it controls from ...
1
vote
1
answer
184
views
getEthToTokenInputPrice miner hack?
Plan to use getEthToTokenInputPrice in a Dapp. I was going to just use a larger sample size spread out over a large time period to mitigate flash loan price manipulation. Someone said this was ...
5
votes
2
answers
2k
views
Who is msg.sender in a nested call chain?
I read about who is msg.sender when calling a contract from a contract, but who is msg.sender when calling a contract from a contract that calls another contract and so on and so forth?
- 18.7k
1
vote
1
answer
113
views
Where is the position of each paramter in a smart contract function when encoded as inputdata in a transaction
When I reviewed the BEC attack, I found the position of each parameters value in real transaction was not corresponding in to definition of function in smart contract.
The exploit transaction is at:
...
- 71
0
votes
0
answers
43
views
How do i get to return value form one smart contract function into another smart contract on private ethereum network?
Here it is my called function.
pragma solidity ^0.4.19;
contract Called{
string public name;
function set(string _var) {
name = _var;
}
function get() view returns (...
- 31
12
votes
2
answers
7k
views
Does view functions cost gas? And how to send transaction in a proper way?
I have a method defined as:
getNames() view public , if i call on it
contractInstance.getNames.estimatedGas() it returns me a non-zero value, why? I mean, view methods should not consume any gas! On ...
- 221
1
vote
0
answers
524
views
How to get transaction hash at time of invoking function?
I have a function as follows:
function setEnergy(address dev, uint256 energy) public returns (bool) {
require(dev != address(0));
amount[dev].energyValue = amount[dev].energyValue + energy;
...
- 2,700
0
votes
1
answer
148
views
Need Solidity software for smart contract, for Multiple Token dispatch [duplicate]
Please I need to distribute tokens to at least 1,500 wallets and can't go through the stress of sending them one by one.
What I need is a smart contract to enable multiple dispatches to several ...
2
votes
2
answers
900
views
How do I deploy a contract, then send and retrieve a string from it?
I wish to store strings on-chain.
From what I understand so far, I need to set up a contract, then I can send transactions (with a string) to that contract which will be stored. Is this the best way ...
- 269
3
votes
1
answer
275
views
How can I set the gas price of a transaction initiated by a contract?
I am writing a contract that will interact with another contract: contract A will call a function defined by contract B. Is it possible to set the gas price that contract A is willing to pay when ...
- 63
1
vote
1
answer
126
views
How to be notified with bad transactions when sending to a JSON-RPC server?
With Ubuntu, I've tried Wallet/Mist and MetaMask on Ropsten testnet: they both notify me with bad transactions before inputting my password. I've tried to do the same thing with a JSON-RPC server, in ...
- 113
1
vote
0
answers
115
views
Implementing a reinforced invoice?
I have a question. My contract structure involves 2 user at address A and B respectively:
First A trigger the logging method from the contract with B's address as parameter. This will record a ...
- 11
5
votes
2
answers
905
views
return (bytes32,bytes32) , returns actual transaction address instead of the real data
I have attached my contract, which works fine on populus and compiles on geth. It is a simple source code: Test() function appends data into my linkedlist that is defined in my library. And get() ...
- 8,404
4
votes
1
answer
936
views
When a contract calls another contracts, can it return values?
When a contract calls another contract, are values returned ? I've seen things like:
function foo() external returns (bool success) {
if( ... ) throw;
return true;
}
But have read that calls ...
- 157
8
votes
3
answers
4k
views
Reading values from a contract: When do I need transactions?
Since reading on the Blockchain does not need performance of other nodes, I wonder how I can get values from a Smart Contract without any transactions. I have created a little example contract:
...
- 213