Class

BlockHeader

final class BlockHeader

Overview

Headers are what miners iterate (changing the nonce until the resulting hash is ≤ the target implied by bits) and what the P2P network gossips before blocks. Use for header-first IBD and for lightweight chain-presence checks that don’t need full transaction data.

Wraps the opaque btck_BlockHeader type; deinit calls btck_block_header_destroy when the last Swift reference drops.

Topics

Initializers

init(Data) throws
Parses a block header from its 80-byte serialized form.

Instance Properties

var bits: UInt32
The difficulty target in compact (nBits) encoding — the threshold the block’s hash must meet or fall below for the proof-of-work to be valid.
var hash: BlockHash
The block’s hash — double-SHA256 of these 80 header bytes.
var nonce: UInt32
The nonce — the UInt32 that miners increment to find a header whose hash satisfies bits. Exhaustively searched during mining; meaningless except as part of the proof-of-work commitment.
var previousHash: BlockHash
The hash of the previous block’s header — the chain linkage field.
var timestamp: UInt32
The block’s timestamp in Unix epoch seconds as claimed by the miner.
var version: Int32
The block version field. Interpreted per BIP 9 for signalling soft-fork readiness; must be ≥ 4 on networks where BIP 65 is active (all current Bitcoin networks).