Questions tagged [erc-20-approve]
The erc-20-approve tag has no usage guidance.
12
questions
0
votes
1answer
12 views
Unable to approve
///
pragma solidity ^0.6.0;
import "https://github.com/OpenZeppelin/openzeppelin-contracts/blob/master/contracts/token/ERC20/IERC20.sol";
import "https://github.com/OpenZeppelin/...
0
votes
1answer
15 views
An attack to my contract similar to ERC-20 approval() exploit
I have
function setNonRecurringFlow(uint256 _child, int256 _remainingSwapCredit) external;
function setRecurringFlow(
uint256 _child,
int256 _maxSwapCredit,
int256 ...
0
votes
0answers
22 views
Which of two ERC-20 approval() bug workarounds in better? [closed]
There is an attack vector to withdraw ERC-20 approved amount twice.
https://docs.openzeppelin.com/contracts/3.x/api/token/erc20 proposes to introduce increaseAllowance(spender, addedValue) and ...
0
votes
0answers
11 views
What is the cause of an “APPROVED” transaction but doesnt do a “TRANSFER” for an ERC-20 Token?
I have a transaction that was approved and I paid $3 in fees. But the token was never "transfered" where and how can I debug what happen to my transaction of why it didn't transfer?
2
votes
1answer
111 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 ...
2
votes
1answer
164 views
How to transfer ERC20 token to another contract and calling contracts function
I need to send an ERC20 Token from a contract to another contract and calling a function of the other contract at the same time.
I know how to transfer an ERC20 Token from solidity to another contract,...
1
vote
1answer
40 views
How to make a delegatecall to external ERC20 token's approve function?
What I would like to do is something like this:
function testCall(uint amount) public virtual returns (bool) {
address tta = address(0xE7B6....);
(bool success, bytes memory result) = tta....
5
votes
0answers
45 views
Not able to use DAI's permit() function
I'm having trouble testing the permit() functionality from the DAI contract. I've read the documentation and a couple of other resources, although, I got the contract code and deployed myself a copy ...
1
vote
1answer
66 views
Usecase for approve and allowance functions of ERC20 token
Could you please enlighten me on how approve and allowance functions work using a usecase? I dont understand the underlying operations of these functions. Especially, when a token owner delegates the ...
0
votes
1answer
44 views
Is it possible for a contract to erc20 approve another contract?
I want my contract (#1) to be able to approve another contract (#2) to transfer erc20 tokens from #1 to #2. Is this possible?
0
votes
0answers
102 views
Want to Access remote dai smart contract in another smart contract
I want to transfer Dai tokens from account1 to account2.
My account1 has 50 DAI tokens.
Kovan Dai contract address given by makerdao is: 0x4F96Fe3b7A6Cf9725f59d353F723c1bDb64CA6Aa.
What I am doing ...
7
votes
4answers
487 views
Is it possible to batch approve + transfer with CREATE2?
In our dapp, we currently have the following user flow:
Approve the Sablier contract to spend up to x ERC20 tokens
Transfer the x ERC20 tokens to the Sablier contract
This is not super bad UX, but ...
