Linked Questions

8
votes
1answer
2k views

Documentation On Multisig Wallet in Mist?

Is there documentation related to the built-in multisig wallet contract in the Mist Wallet? I see there are many additional functions in this contract like changing / adding / removing owners etc. ...
6
votes
1answer
2k views

How is an ABI stored in bytecode?

I'm trying to understand how a simple hex string like 0x25d8dcf2 is enough information to execute a function in a contract. I've read up on the ABI and understand that the hex string is basically just ...
5
votes
2answers
3k views

Understanding nameReg.call(“register”, “MyName”) style call between contracts

Here's an example from solidity docs on Address type methods(call method specifically): address nameReg = 0x72ba7d8e73fe8eb666ea66babc8116a41bfb10e2; nameReg.call("register", "MyName"); ...
8
votes
2answers
5k views

Get smartcontract token balance via JSON RPC

Via Geth commandline I can get my smartcontract token balance with: var mytest = eth.contract([{interface}]).at(contract address); mytest.balanceOf(eth.accounts[0]) >998 I want to present the ...
8
votes
1answer
4k views

How to pass arbitrary bytes to a function (2016)

I'm trying to implement a contract which will store bytes blob, a dynamic bytes array. For example I have following struct: Sign { address signer; bytes16 signType; bytes sign; } plus ...
6
votes
2answers
796 views

Why does an empty message still invoke the code of the contract?

An empty message still invokes the code of the contract and is the mechanism that allows Solidity to implement a feature of a fallback function per contract. But when msg.data is empty, why does ...
4
votes
2answers
3k views

What is “data” param of rawTx? How to send ETH by using web3

I want to send eth by using web3 on testnet. Source address is 0xbddf0bf3ac858d7fb8a2bdda55884d61779ba5a9. The destination is 0x8005ceb675d2ff8c989cc95354438b9fab568681. I found the example on web3 ...
4
votes
2answers
2k views

Solidity return string not hex?

Currently I'm using ether.camp to create a contract. At this stage it simply gets and stores some values. However when I try and get the values they are in bytes/hex even though the return type is ...
7
votes
1answer
1k views

When does the fallback function get called?

Is it true to say that if the first four bytes of an Ethereum's transaction does not contain one of the contract's encoded function calls, then the fallback function will be called? In other words if ...
8
votes
2answers
782 views

Can msg.data be used as an identifier?

I'm looking at the multisig wallet implementation here and I see the usage of sha3(msg.data,block.number) being used as an identifier. What exactly is inside the msg.data and why is it unique enough ...
6
votes
2answers
530 views

Is sending some datas in the data field safe?

An airdrop ask to send it 0ETH with 150000 GAS and some datas in DATA field. Is it safe? What could be the aim of this transaction? Thanks.
2
votes
1answer
2k views

How to know the hex code to use in data to call a specific contract function?

For instance, on the BAT ico site, you can see the crowdsale contract address, the ABI and also a string to use in the data part of your transaction if you don't want to call the contract function ...
5
votes
1answer
1k views

How do you get a string value from msg.data in the fallback function?

Im trying to do what The DAO did and do something when a sender sent money to my contract address. But im not sure how to. The something I want to do is to just create a new user in a mapping with the ...
2
votes
1answer
746 views

Where does ABI decoding take place?

I'm trying to understand the winning contract from the Underhanded Solidity Contest. That contract apparently caused an overflow in the ABI decoder, but I'm having a hard time understanding where in ...
5
votes
1answer
655 views

Accessing the last function parameter from msg.data

I have a fallback (unnamed) function in my contract and I know that the last parameter (or first, does not matter) passed is always an uint. Is it possible to somehow access it though the msg.data?

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