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8
votes
1answer
1k views

How can I generate a V3 of the Ethereum wallet file format in js, from strings: 'Passphrase' and 'Email or username' required by Quorumwallet?

Quorum Wallet prompts for a Passphrase and a Email or username to generate the account. On the FAQs there is a description of the algorithm to generate the account: What is the algorithm used to ...
4
votes
2answers
1k views

Watching for changes in web3.isConnected()

I am using Meteor & Web3 to talk to a Geth node, and would like to have an event fire in web3 when the Geth node goes down. Web3 has the ability to add callbacks to web3.eth.isSyncing to detect ...
2
votes
1answer
41 views

multi-step game, would the contract stop for a while for another transaction to come

To make my question specific, what I want to develop is a multi-step game. And the thing I want to realize is, let's say now we have the game taking players A & B included, and both A & B have ...
9
votes
3answers
4k views

Is it possible to run the Ethereum Wallet with a remote Blockchain?

To run the Ethereum Wallet on a small computer like a Phone or a Netbook it would useful to have a light client, possibly that connects to a hosted full Ethereum node. Is this currently possible?
1
vote
3answers
808 views

Syntax highlighting for Solidity VS Code extension not working on linux

Even if the extension installation completes correctly, syntax highlighting does not work.
4
votes
1answer
760 views

How do I access a contract by its address (within Mix)

I am trying to use Mix to test multiple instances of the same contract, therefore I am trying to select a contract by address, but currently without success. Is this a limitation within Mix or my ...
2
votes
1answer
57 views

Where are contracts actually running? [duplicate]

I wonder where "Smart Contracts" are actually running: Are they running on every node in the network? I rather doubt this, given the costs for running the contrat. If my assumption is correct and the ...
1
vote
1answer
142 views

does the smart contract have something similar to the locktime in bitcoin?

I want to develop a multi step gambling game with the contract, does the smart contract have something similar to the locktime in bitcoin to make the transactions can not be processed before certain ...
6
votes
1answer
242 views

Architecture best practices for decentralized, multi-seller sales platform

My question revolves around contracts creating subcontracts, and best practices with contract creation. The Story: I'm creating a tool to help people buy Widgets, Gizmos and Ratchets, all of which ...
2
votes
0answers
38 views

I downloaded the etherum wallet, how do you back it up wallet. [duplicate]

I saw somewhere to copy your etherum key and email it to yourself. this way you have can find it. I would imagine this would be needed, say your computer gets stolen. Please if anyone has suggestions ...
2
votes
1answer
1k views

How do you restore a wallet in Mist on OSX from a Windows backup?

In Mist on Windows I went to Accounts -> Backup -> Application Data, and backed up the Mist folder it pointed to. I assume this is backing up my wallet contracts, since Accounts -> Backup -> Accounts ...
4
votes
1answer
140 views

Where to find Ethereum introduction material?

I'm from Chile were few people know about Bitcoin and even less about Ethereum. I finished my studies last year in business engineering and I've been involved with the technology since 2013. Right ...
6
votes
3answers
2k views

How can Ethereum be useful in Insurance Industry? [closed]

How Ethereum can be useful to Insurance Industry ? I'm a Web Developer, still learning about Smart Contracts, and familiar with Blockchain fundamentals to some extent. Came across ...
18
votes
2answers
6k views

Deploying the Greeter contract via the geth CLI is not registering in my private blockchain

I am running a local private Ethereum blockchain using: geth --networkid 60098 --genesis CustomGenesis.json --nodiscover --maxpeers 0 --rpc --rpccorsdomain "http://localhost:3000" --datadir "./data" ...
3
votes
1answer
4k views

Software to measure power consumption of mining?

Does anyone know of any good software that will measure my PC's power consumption while I mine ethereum? I'm aware I could buy something to measure it on the socket, but free software is well, free.
8
votes
3answers
15k views

Ethereum Node Stuck, Can't Sync

I'm using a Macbook Pro OS X Version 10.9.5 and am unable to get through the syncing phase. "Ethereum node needs to sync, please wait..." is exactly what is prompt but regardless of the time I wait, ...
3
votes
2answers
417 views

how to develop a multi-step game with the contract

I want to develop a multi step gambling game, my question is can several transactions be sent to the game contract separately(some first, some after) but all contribute to the result?
5
votes
1answer
520 views

Why is it that the Mist client can not display the transactions?

"Latest Transactions" not updating in Mist Wallet after sending Eth from Polo to my wallet. Balance is updating fine but can't see any transactions since 3/31.
2
votes
0answers
105 views

Mix wont connect to nodes: Error status 0

I managed to configure Morden test network to run, but Mix is unable to discover testnet node, it is giving this error: A "Unable to initiate request to the live network. Please verify your ethereum ...
9
votes
3answers
1k views

How would stablecoins work on Ethereum?

The idea of a stablecoin in Ethereum is to create a token that is pegged to the price of say $1 USD. What are the main ways of achieving a stable cryptocurrency? What DApps are implementing them and ...
2
votes
0answers
37 views

Is the term “open execution” wrong in any way? [closed]

I read a post discussing Ethereum, and how it can be thought of as the next step of the "open source" movement of software, and he coined the term "open execution," and I rather liked it. The real ...
4
votes
1answer
104 views

Is it conceivable to have a DApp that doesn't issue tokens?

I'm trying to nail down my explanations to people when they ask about Ethereum, and I'm trying to think of applications that wouldn't benefit from dispersing a token for some reason or another.
2
votes
1answer
98 views

How is the amount of gas required by an op code determined? [duplicate]

Is this proportional to time required to process? Is a high gas transaction more expensive for the miner to include in a block and does it add more to blockchain size than a low gas transaction?
8
votes
1answer
982 views

Losing connection between nodes on private network

I have 3 nodes running on a private network. After asking this question, I've manually added node1 as peer to node2 and node3, so my network looks like this: _______ ...
8
votes
3answers
3k views

How can I accept Bitcoin payment in a smart contract? What would be the code for that?

I will create my personal token and I would like to be able to sell it for ETH and BTC. I know how to add the sell function for ETH, but how can I sell the tokens for BTC? The ETH sell function I ...
2
votes
1answer
440 views

How can I confirm validity of deployed contract?

I have deployed contract using mist browser 0.6.1 How can I do code validity check on ethereum mist?
21
votes
2answers
78k views

What's the best hardware for Mining Ether?

As my title says, I am a complete newbie to the Ethereum Project, but not to the cryptography in general. Although this will be the first time I will consider investing in the mining process. And I ...
9
votes
1answer
6k views

Is it possible to have mappings inside mappings?

Is this possible? mapping(address => mapping(uint => customStruct[])) someName Because I cannot debug and find my mistake... is there not enough gas, or it crashes on this code, while trying ...
6
votes
2answers
2k views

Smart contract based betting

Let’s say I want to enter into a bet with my friend that if it rains 10 days from now, I will pay him $100. If it doesn’t, he will pay me $100. Would it be possible to take advantage of smart ...
1
vote
0answers
44 views

newcomer here, any suggestions about developing a new smart contract [closed]

I want to develop a new smart contract as my graduation project, any suggestions about which client to use to develop a new contract?
1
vote
1answer
59 views

How to get Mix UI to show buttons at top of scenario module

Was watching this video and saw at about 8:11 a bunch of UI buttons at the top of the Mix scenario module (right 1/3 of screen) that I don't have in mine. I verified I have the latest, 1.0.2. I am ...
11
votes
1answer
4k views

Peer discovery not working on private network

I'm running 3 nodes with the following command: geth --verbosity 4 --autodag --nat any --genesis /opt/blockchain/genesis.json \ --datadir /opt/blockchain/data --networkid 4828 --port 30303 --rpc ...
7
votes
2answers
2k views

What is the purpose of tokenRecipient contract in token example?

The example of how to create a token (https://www.ethereum.org/token) includes contract tokenRecipient. Why is it there?
4
votes
1answer
4k views

How to create a data structure in Solidity with no limits on size?

In solidity we are not allowed recursive Structs, so I cannot create a recursive data structure with unlimited nodes. Similarly, Solidity Arrays are fixed to the size you initialize them with. So I ...
5
votes
1answer
6k views

Mining wattage on Sapphire R9-390

got my first rig coming online. 6x Sapphire R9-390. I have 2x 750w power supply. Am I good? Does anyone have these cards and know the watt draw? Thank you :-)
7
votes
1answer
1k views

do the contracts of ethereum have the access to the nonce of the blocks?

by this question I mean when we try to develop a gambling game contract we need some random input, can we just use the nonce data from some certain blocks? (I just start learning blockchain, I'm from ...
12
votes
3answers
10k views

Is there any Ether mixer / tumbler available?

Quick checking around there are exactly two references to an Ether Mixer - this non functioning and here (r/ethereum) 24 days ago. Unless I am missing something how can I hide the source of an ETH ...
3
votes
1answer
1k views

Dangling hash node ref: too many open files

I'm running two supernodes with the geth client. At peak times they have 500-800 connections and handle around 16GB traffic per hour. This is how I run the node: geth --networkid "1" --identity "...
4
votes
2answers
1k views

truffle deploy to geth failing, generating “receipt not found” repeatedly from geth

I've just installed truffle on an ubuntu virtualbox, and it is failing to deploy to a geth dev setup. Geth gives me a never-ending receipt not found for transaction ...
62
votes
2answers
49k views

What is the relationship between Mist and Ethereum Wallet?

In https://github.com/ethereum/mist/releases 0.3.6 the files are named Mist. Starting in 0.3.7 the files are named Ethereum-Wallet. Will files named Mist take over in the future, or will there be 2 ...
1
vote
0answers
148 views

What are the preferred protocols to integrate external data sources & sinks with a BC network? [closed]

I'd like to trigger events and send data to external non-ethereum network applications. What is the preferred communication protocol and mechanism to use so as not to impact BC processing? My ...
23
votes
2answers
9k views

How do you delete/remove/hide contracts from Ethereum Wallet (aka mist)?

I have tons of experimental contracts I created as part of doing tutorials which I no longer need. I know I can kill the contract (from https://www.ethereum.org/greeter tutorial) but that still leaves ...
4
votes
1answer
214 views

The third party api failure problem

I wanted to highlight a problem we all suffer from when using third party API's. Let's say you want to make an ethereum transaction. Normally the API will return a txid when the request is successful. ...
7
votes
1answer
5k views

How to unlock accounts programmatically after the node has started?

Is there any way of just unlocking accounts without opening the console with geth? I'm writing some scripts to automate cluster generation and I wish I could just call geth to unlocking some accounts ...
6
votes
0answers
344 views

testrpc 2.0.0 - cannot find module 'memdown'

Trying to get testrpc (2.0.0) working on an ubuntu virtualbox, and getting this error when I run it: mowliv@u4:~$ testrpc module.js:341 throw err; ^ Error: Cannot find module 'memdown' ...
2
votes
1answer
337 views

sendTransaction from iPhone app

How do I call sendTransaction from within an iPhone app? I was thinking of running a web to Geth proxy where the iPhone app would call the Api exposed by the proxy which in turn calls my self hosted ...
7
votes
4answers
519 views

Splice Struct Entry by Index in Solidity

I have a struct and I'd like to remove an item by index: struct Payout { address addr; uint yield; } Payout[] public payouts; I'm not familiar with structs and more use to dealing with arrays ...
3
votes
1answer
653 views

ethminer || Segmentation fault: 11 [duplicate]

I recently updated cpp-ethereum. I am now on ethminer version 1.2.3 when I start it to mine with ethminer --opencl-device 1 I get the folowing output. Getting work package... Segmentation fault: 11 ...
24
votes
1answer
7k views

Is it possible to get the transaction hash from within a Solidity function call?

Within a Solidity function, is the transaction hash available as a global variable from within the contract? I would have thought it would be something like tx.hash in the same way you can do tx....
3
votes
1answer
744 views

Nethereum and UWP on .Net c#

Is there a way to make Nethereum work with an UWP app ? Because when I try to download the package with nuget It raise an error. I enter the following command in Nuget Package Manager: Install-...

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