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How to create transaction using bitcoin-qt console

Example of a transaction with single input and output

Start bitcoin-qt (on testnet)

bitcoin-qt -testnet

Open console

How to get bitcoins for development using Regtest

Start bitcoind

> bitcoind -regtest -daemon

Generate block chain

> bitcoin-cli -regtest generate 101

How to activate segwit on regtest

Start bitcoind

> bitcoind -regtest -daemon

Generate block chain

> bitcoin-cli -regtest generate 432

How to get Public Key of a Bitcoin Address

Generate bitcoin address

> getnewaddress
mkAhnkryoSs3dLWeBhbhJsw5d1LMs3B3Lt

Get public key

> validateaddress mkAhnkryoSs3dLWeBhbhJsw5d1LMs3B3Lt

How compute double sha256

This example is from BIP 143 - Native P2WPKH

Compute double sha256

> export PREV_OUTS=fff7f7881a8099afa6940d42d1e7f6362bec38171ea3edf433541db4e4ad969f00000000ef51e1b804cc89d182d279655c3aa89e815b1b309fe287d9b2b55d57b90ec68a01000000
> echo -n $PREV_OUTS | xxd -r -p | openssl dgst -sha256 -binary | openssl dgst -sha256
96b827c8483d4e9b96712b6713a7b68d6e8003a781feba36c31143470b4efd37

How to compute OP_HASH160 of public key

OP_HASH160 of public key = RIPEMD160(SHA256(ECDSA_publicKey))

1. Generate address

> getnewaddress
mpLwhoaRWxfgdQAz8JnnH7NUuhS157DM61

2. Get public key

How to create scriptPubKey for P2PKH

1. Get public key hash

Get the public key hash by computing OP_HASH160 of public key

In this example:

public key: 033e8c5dcb8e35670de496b57c1fa4366800ce3be5fded9b8800759881bc8da2e5
public key hash: 60d47ac02b129c08f94232ea506d1826424fe7be

How to create bitcoin address

0. Overview

Address = base58 encode ([version byte][public key hash][checksum])

version byte = 00 (for P2PKH on mainnet)

public key hash = RIPEMD160(SHA256(public key))

How to convert private key to WIF

0. Overview

WIF = base58check encode ([version byte][private key][checksum])

version byte = 80 for mainnet, ef for testnet and regtest

checksum = first 4 bytes of double SHA256 of private key

	# Simple wrappers for Material Design Lite text fields to use with SimpleForm (Rails)

	SimpleForm.setup do \|config\|

	config.wrappers :mdl_field, tag: 'div', class: 'mdl-textfield mdl-js-textfield', error_class: 'is-invalid' do \|b\|
	b.use :html5
	b.use :input, class: 'mdl-textfield__input'
	b.use :label, class: 'mdl-textfield__label'
	b.use :error, wrap_with: { tag: :span, class: "mdl-textfield__error" }
	end