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Hash of the transaction VS Transaction Hash or Transaction ID

I just want to be sure I understood well how each of them are generated. I'm a bit confused because of the similarity of the names and because I couldn't find in the yellow paper how the transaction ...
0
votes
1answer
253 views

Solidity test file reaches gas limit due to imports

I have a sol contract X.sol and a sol test file TestX.sol. X.sol is large: ~4m Gas after optimisation TextX.sol compiles, migrates and executes tests fine when just executing a single test - testY, ...
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votes
1answer
260 views

Can't set gas limit for oraclize callback function higher than the default 200000

Could you please help me with the following. I am using OraclizeIt (https://github.com/oraclize/ethereum-api) to retrieve a JSON from some other service via REST. Basically the smart contract method ...
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1answer
80 views

How can I decode transaction input to know what method was called and what arguments were passed in (and arguments types)?

following to the approach explained here to use etherscan api from Python to get transactions info such as input How to retrieve transactions' info such as gaslimit and gasprice from Etherscan? ...
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votes
1answer
1k views

GETH ~ why do i get ERROR: no space left on device

While downloading blockchain im getting this error Fatal: Error starting protocol stack: write /root/.ethereum/geth/chaindata/230944.ldb: no space left on device how this can be resolved? Im ...
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votes
2answers
748 views

truffle/web3 event listeners returns nothing

We have an event being triggered in a contract and our listeners on the client cant receive the return value. https://gist.github.com/stupeters187/9529b54fe0d48ee606ad06ced6b16031 Update: metamask ...
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votes
1answer
121 views

Issue in creating App using Monax :- Contract not found in JSON

I am trying to create applications using Monax. I am using the reference given in Monax for developing app https://github.com/monax/hello-doug. I have created hello-chain as mentioned in their Read-me....
0
votes
1answer
189 views

Monax :-Issue in executing job configuration file

I am using Monax version 0.18.0.I am following the tutorial for deploying contracts in Monax https://monax.io/docs/getting-started/. I have used the sample contract defined in their starting tutorial....
0
votes
1answer
2k views

Contract Not sending ether to other account

I have created a contract which store the address of the users and i want to send 1 ether all the users stored in array. Here is my code contract project{ address public user; bytes32[10] ...
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votes
2answers
600 views

Public struct array variable getter

I create a struct array and map it to an address: contract MyContract { struct something { bytes32 test1; bytes32 test2; bytes32 test3; } mapping (address => ...
0
votes
1answer
218 views

Solidity smart contract inherited function output failed

I'm trying to inherit a function from the parent contract into child contract and its working fine in remix JavaScript VM. I did the following steps: Deployed the parent contract in remix JavaScript ...
0
votes
1answer
1k views

ETH wallet error

I want to download the ETH wallet and make light synchronization on my PC. I downloaded ethereum wallet, but after launch, the Checksum mismatch in downloaded node crashes! MD5: 308 ... Please install ...
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votes
1answer
77 views

Smart contract returning values as zeros

pragma solidity ^0.4.18; contract TransManager { //state variables // contract owner address private creator; uint transCounter; // File Meta metaData struct metaData{ uint id; ...
0
votes
1answer
474 views

Ethereum light node: Light vs Cache vs fastsync

There are many different options when running a Ethereum node. I want to make sure I pick the right options before I start downloading the blockchain... can someone explain the advantages of using: —...
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votes
1answer
509 views

Transfer transaction

I need help with the following : I have made an EOS token transfer transaction from myetherwallet account to another account and I have been told it can be reversed "You would need this account to ...
0
votes
2answers
547 views

Why is string getter returning an empty response?

This is a sequence of another question I asked. I have the following contract contract User { string publicKey; function setPublicKey(string _publicKey) onlyOwner { ...
0
votes
1answer
307 views

eth.getBalance(eth.coinbase) = 0, node/client not fully synced yet

I just started to get my fingertips wet with Ethereum and Dapps. After receiving some ether on Ropsten to test with: https://ropsten.etherscan.io/address/0x05c86fc0ec0b80715f1cbc2fa96e86ba18e2eb90 I ...
0
votes
1answer
2k views

Explanation on why I need an address, a pool and a wallet

I am very new to this world so this is a very newby question but as much as I have searched there don't seem to be any newbie getting started guide that spells this stuff out. I am trying to setup my ...
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votes
2answers
1k views

Has it been more profitable to mine or buy Ethereum?

Given all the posts speculating about future performance of Ethereum, I figured I'd ask and answer a question about past performance: Historically, would I have ended up with more Ethereum if I had ...
0
votes
1answer
104 views

Can manage node in my ethereum private network

I have created ethereum private network. there are two node got connected with in this network. both are mining. I have created small contract for transaction. All transaction is happening through my ...
0
votes
1answer
195 views

What exactly is Ether currency in Ethereum? [duplicate]

What is exactly Ether currency in Ethereum? Is it a token or a set of some functions that generate some tokens? If so, how many of those functions exist and what do they do? Are they hardcoded in the ...
0
votes
0answers
40 views

Are function modifiers added to the stack in solidity? [duplicate]

I've got a function with a decent number of modifiers and I hit the CompilerError: Stack too deep, try removing local variables error. If I remove one of the modifiers though, everything's all right. ...
0
votes
1answer
371 views

Setting values of an byte array dynamically

If I set the values of an array as follows, am I wrong? uint256 n = 0; bytes32[n] example; function getArraySize(uint256 arraySize) public returns(uint256 size) { size = arraySize; return size; }...
0
votes
1answer
225 views

web3.eth.accounts.wallet.add(account) not working

I need help with adding a new wallet to a web3 instance. e.g.: web3 = new Web3(new Web3.providers.HttpProvider(connectionString)); const account = await web3.eth.accounts.privateKeyToAccount('0x'+...
0
votes
2answers
48 views

Integrate more then one user with one ethereum account

I have many users inside the organization and I want to use same ethereum account for all the users , but with different usernames, so it there anyway to do that ?
0
votes
2answers
5k views

Migrating from paper wallet to Ledger Nano S with private key ONLY

I recently purchased a Ledger Nano S, and I'm wanting to transfer my Ether from my paper wallet to the new ledger device. Please forgive my ignorance, but I have no idea how I can transfer my Ether ...
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votes
3answers
3k views

Ethereum Wallet Start Mining option is disabled

I just downloaded Ethereum wallet and after syncing the blocks when I went to Start mining to get some Ether, the menu button is grayed out, its disabled This is my wallet, in case if you can send me ...
0
votes
1answer
216 views

how to deal with bytes32 to string in javascript?

I am going to set a email address from users and going to save it to ethereum network. I kept email as bytes32 in smart contract and when I am sending the value to javascript i am getting always a ...
0
votes
1answer
50 views

Ethereum fork that implements transaction ordering

Hyperledger fabric has its consensus that contains Transactions endorsement Transactions ordering Transactions committed to a block I wonder if there is an Ethereum consensus or fork that would have ...
0
votes
1answer
189 views

Best way to do USD math in Solidity?

Pardon the n00b question! I am trying to do some simple math in solidity using USD values. For example, say the start price of a token offering is $0.50 USD and the contribution is $10.00 USD, then ...
0
votes
1answer
105 views

identifier problem with “require”

function transfer(address to, uint tokens) public returns (bool success) ; uint256 public max_contribution = 50 ether; uint256 public min_contribution = 0.1 ether; require (msg.value &...
0
votes
1answer
188 views

Creating an offline address creator for Ethereum

I found this Bitcoin Paper Wallet: https://bitcoinpaperwallet.com/bitcoinpaperwallet/generate-wallet.html I would like to add it Ethereum just for fun. On this question, they show how to create ...
0
votes
1answer
492 views

JSON RPC + web3: Subscribe to Solidity events

When using web3 and the JSON RPC, is there a way to subscribe to Solidity events? For instance, I want to subscribe to every event Transfer(address indexed from, address indexed to, uint256 value); ...
0
votes
2answers
73 views

Suggestion on my asset contract

I created asset transaction smart contract. Functions are Create Assets (asset id, asset details, with owner) and pushing into array list. Get Assets by owner address: Looping assets array and get ...
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votes
2answers
449 views

Ethereum transaction RangeError: private key length is invalid

I'm running a tutorial on how to sign an ethereum transaction programmatically, and I'm getting the following error: RangeError: private key length is invalid This is the code: var Web3 = require(...
0
votes
1answer
145 views

truffle-contract: cannot test method before real consume ether method

I am using truffle-contract for connecting between frontend and smart contract. Currently, I can call method on smart contract and can consume ether successfully. const result = await instance....
0
votes
2answers
915 views

create ethereum wallet in Api

I want to create an Ethereum wallet, and I need an address and a private key, but I am unable to generate both. Please suggest a way to generate key pairs.
0
votes
1answer
58 views

how to get the real balance of ETH by eth_getbalance

as I know, the transaction should be confirmed by 11 times then it will be done. but when i use eth_getbalance to get the balance ,it will return some fake balance without confirmed. so How can I get ...
0
votes
1answer
477 views

Transaction signing fails Invalid RLP.“,”data“:”RlpExpectedToBeList"

I'm trying to sign and push a transaction using ethereumjs and Infura. It seems to be working and I'm getting a transaction hash back, but the transaction is not visible on Etherscan, and when I'm ...
0
votes
1answer
487 views

Solidity Debugging in Remix

I am working Remix Browser for the following simple Contract. I had a couple of questions. I could not find the right answers. During Contract Creation: It gives the following error. What is ...
0
votes
2answers
1k views

What is the maximum number of blocks in a blockchain?

What is the maximum number of blocks in a blockchain?
0
votes
1answer
241 views

Ropsten Network - geth console does'nt give updated blocknumber

I have used the command : geth --testnet --syncmode "fast" --rpc --rpcapi db,eth,net,web3,personal --cache=1024 --rpcport 8545 --rpcaddr 127.0.0.1 --rpccorsdomain "*" --bootnodes "enode://...
0
votes
1answer
184 views

Smart contract with authorized actions based on addresses

I want to build a service where users can sign up (off-chain) to get credentials which give them the right to perform certain on-chain actions. For example, lets pretend I'm building a service where ...
0
votes
2answers
295 views

Calculate integer input length

I need to get the length of input which is an integer in bytes function mine(string s , uint i ) public view returns () { return (length of i); }
0
votes
1answer
171 views

Why I do not get returned value of function of my smart contract using testRPC and a Graphical User Interface?

I have a smart contract that is tested with remix and it works well. Its code is as follows : contract Weechain: pragma solidity ^0.4.15; // --------------------------------------------------------...
0
votes
1answer
151 views

How to retrieve transactions' info such as gaslimit and gasprice from Etherscan?

This link shows the latest 500k transactions, and by clicking each one it opens a page with its info including gaslimit, gasprice, usedgas etc. https://etherscan.io/txs How can i retrieve the ...
0
votes
2answers
823 views

Increase all values of mapping or array without loop

Would it be possible to increase all the values of a mapping or array (without a loop)? Example: mapping(address => uint) score; uint[] values; function increase_scores() public { // ...
0
votes
1answer
533 views

Import account from one geth node to another geth node

I had a geth node where i created an account. Then i backed up the keystore folder just in case. I had to format the pc and install geth again. So i would like to know how can i import my old account ...
0
votes
3answers
199 views

Error trying to create a crowdfunding contract?

I am using the template code found on the Ethereum website for crowdfunding and when I insert it in the solidity contract source code in the Ethereum wallet, it returns: Unused local variable ...
0
votes
1answer
2k views

why am I getting this error : Fatal: Error starting protocol stack: datadir already used by another process

I was trying out on creating a private ethereum network by following this link . However the first connection took too long so I uninstalled it and reinstalled it again. However when I try to run ...

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