Ethereum questions and answers

Ethereum

Geth IPC endpoint unavailable after upgrading from 1.3.5 to 1.4.10

This question is somewhat related to this (https://ethereum.stackexchange.com/questions/3277/how-to-connect-attach-to-a-remote-node) one. Following the suggestion in the comments from this (https://ethereum.stackexchange.com/questions/7497/geth-bug-when-working-with-address-arrays) one, I upgraded geth to v1.4.10 and launched it and launched it on a private net: geth --datadir "data_dir" --mine --minerthreads 3 --networkid 13 --rpcapi eth,web3,personal --rpc --maxpeers 0 which outputs: I0728 ....

Amelia Amelia: 26 minutes ago

Ethereum

Front-end IPFS library

I'm looking for a light IFPS library that I can include on the front-end. I only need to save files and retrieve the hash. Using Browserify on https://github.com/ipfs/js-ipfs-api is about 2.2mb, which seems high. https://www.npmjs.com/package/browser-ipfs Looks good but hasn't been updated in two years. ....

Olivia Olivia: 56 minutes ago

Ethereum

Deployment of Blockchain Dapp application on cloud!

I have my dapp in progress using PrivateNet, Metamask, HTML, CSS, JAVASCRIPT & Solidity in Ethereum. After the finishing of my application I just wanted to host my application on cloud. As of now when I searched for the deployment, I didn't get such blockchain environment like Heroku . Can ....

Mia Mia: 1 hour ago

Ethereum

Does externally owned account have two parameters ("codehash" and "storage root")?

I often see the following figure. That figure explains to me that every contract account has four parameters for computing the global state root. But I can't understand what parameters the externally owned account has for calculating the global state root. I think the user's account should have two parabeters(nonce ....

Mia Mia: 3 hours ago

Ethereum

how transaction in block-chain is validated

Please explain complete procedure/journey how transaction in block-chain get validated by miners, From broadcast of transaction to become part of new block. ....

Olivia Olivia: 3 hours ago

Ethereum

who pays for gas in a refund transaction

I would like to know who pays the gas when a transaction is refunded by the smart contract. Suppose if a sender sends some amount of money to a smart contract, and it finds out that there is some issue with the transaction and wants to refund the sender. Who ....

Charlotte Charlotte: 4 hours ago

Ethereum

How to get price of ETH to DAI within smart contract?

Is it possible to get the current price of Ethereum to Dai within a smart contract? Can this be done without a transaction, using a read operation by the nodes on some kind of existing decentralized exchange or the dai contract itself? ....

Emma Emma: 5 hours ago

Ethereum

Retrieve specific account in truffle 5 console

I am following a truffle tutorial where the individual users web3.eth.accounts to retrieve all the accounts from Ganash. However that seemed depreciated and to duplicate his results I used web3.eth.getAccounts() as you can see below. However a next command is ran in truffle console web3.eth.accounts which presents account at position ....

Mia Mia: 6 hours ago

Ethereum

Instantiate web3 to work with the real Ethereum network

I know how to instantiate web3 to work with a local test network: var web3Instance = new Web3(new Web3.providers.HttpProvider("http://localhost:8545")); How do I change this code to connect to the real network? ....

Elijah Elijah: 7 hours ago

Ethereum

Installation of pyethapp fails on Raspberry Pi

I'm trying to install pyethapp on Raspberry PI B+ sudo pip install pyethapp getting error Complete output from command python setup.py egg_info: Couldn't find index page for 'pytest-runner' (maybe misspelled?) No local packages or download links found for pytest-runner>2.0,<3 Traceback (most recent call last): File "<string>", line 1, in <module> ....

Henry Henry: 7 hours ago