All Questions
Tagged with contract-invocation transactions
123 questions
4
votes
1
answer
6k
views
Can I send ethereum to a contract outside of its constructor?
How do I fund Solidity contracts with Ether? The example in the Solidity FAQ, http://solidity.readthedocs.io/en/develop/frequently-asked-questions.html#store-ether-in-a-contract, funds a contract via ...
- 614
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
1
answer
840
views
Why is my TX failing due to lack of gas even though the correct amount of gas was supplied?
Caveat: I tried to provide links to my transactions and addresses in etherscan.io, but I "need at least 10 reputation to post more than 2 links."
I have an account that I want to sweep. I want to ...
- 211
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
5
votes
2
answers
1k
views
calling a contract function from another contract [out of gas]
Consider the following two contracts A and B. Suppose I store these in
a and b. Then when I make a call and try to pass two addresses as follows:
a.reqswap(b.address,eth.accounts[0],eth.accounts[1])
...
- 331
7
votes
2
answers
3k
views
How can I use "eth_sendTransaction" to invoke a contract and get logs?
I have deployed：
contract test {
function multiply(uint a) returns(uint d) {
return a * 7;
}
}
I can call the contract with "eth_call" :
mpsp@ubuntu-slave2:~$ ...
- 153
1
vote
0
answers
60
views
Can two state-changing transactions be in a single block? [duplicate]
I don't know how Ethereum verifies the atomicity of the state of a contract in the mining process.
Say I have a greet-counting contract.
If two people call the greet function in (almost) the same ...
- 11
3
votes
1
answer
2k
views
NodeJS+web3 - Reading from a contract works, how about writing to a contract? [duplicate]
In Mist you can call functions of contracts in two ways:
On the left panel, to call functions that read from a contract (the result is immediate).
On the right panel, to call functions that write ...
- 152
7
votes
1
answer
1k
views
I created a wallet contract, sent ether to it and now cannot send to another account
While experimenting. I creating a wallet contract. Here is the address: https://etherscan.io/address/0xC23501aB1E8E5C5EDB0fFA83C5A4DcFb9c31a355 I sent some ether to it. Now I want to send the ether ...
3
votes
1
answer
104
views
Same functionality, new contract for new usage?
When different people use the same contract functionality, do they send to the same contract address? Or do they create their own new copies of the contract at a different address? If they use the ...
- 2,426
7
votes
1
answer
3k
views
Passing ether with call to Solidity function
I have deployed a contract to testnet which appears to function.
I have a function named contribute which gets the ether from the msg.value. The function is below and doesn't take any arguments.
I ...
- 397
2
votes
1
answer
2k
views
Understanding data payload on contract call [duplicate]
I'm running truffle's default example Metacoin:
import "ConvertLib.sol";
contract MetaCoin {
mapping (address => uint) balances;
function MetaCoin() {
balances[tx.origin] = 10000;
}
...
- 2,491
20
votes
2
answers
4k
views
What happens when a smart contract gets several similar calls in the same block?
What happens when a smart contract gets several similar calls in the same block?
Consider for instance this greeter:
contract greeter {
string name;
function setName(string name_) {
...
- 1,109
5
votes
1
answer
462
views
Proper ethereum exchange workflow
I've recently found out, that there's no convenient way to monitor transactions to 'externally owned account' generated by some contract.
I went to various forums and ethereum bugtrackers for an ...
- 51
21
votes
1
answer
2k
views
What is the order and concurrency behavior of multiple calls to a contract in a single transaction?
Suppose a contract has three call APIs that have side effects.
What's the behavior if I try to:
Call all three APIs from one address (i.e. issue three transactions if from nodejs). Are all three ...
- 4,291
2
votes
2
answers
3k
views
How can i sent ETH from a contract wallet to another account?
Use the mist wallet 0.3.9.
The ETH from a pool is sent to a wallet address. How can I send the ETH from wallet to account?
When I try to send from the wallet address to an exchange address, I saw ...
- 21
16
votes
1
answer
8k
views
How much does it cost to use a contract?
Still new to ethereum and would like to know the price for a contract.
- 4,810
195
votes
2
answers
60k
views
What is the difference between a transaction and a call?
What is the difference between a transaction and a call? In some interfaces, I can interact with contracts via calls or via transactions. What is the difference between the two, and can contracts also ...
- 7,636
12
votes
2
answers
997
views
What happens when two smart contracts recursively call each other?
As I understand it, a smart contract can "call" other smart contracts. So what happens when two smart contracts call each other in a recursive loop? Does the whole network break down and die?
- 1,405
30
votes
4
answers
11k
views
Does every node execute the contract code for each transaction?
This question was asked on Reddit a while ago:
When a node sends a transaction to the network and has the receiver as a contract, does every node execute the contract bytecode with the inputs to ...
- 8,981
28
votes
2
answers
22k
views
How do I know how much gas to use when calling a contract?
When I am calling (sending a transaction to) a contract how do I determine how much gas to use? Is there a way to calculate this upfront & what happens if I send too much / too few gas?
- 8,981
91
votes
9
answers
26k
views
Can contracts pay the gas instead of the message sender?
Is it possible for a contract to pay the gas costs (or part of it) that result from the contract being called? Or does the sender of a message always pay the resulting gas costs no matter what?
- 7,636