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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server340 file guides

Release published 2026-10-28 · Snapshot fetched 2026-11-01. Latest stable release at fetch time; development branches and Git history are excluded. Only the selected code window and visible folders load here.

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1// Copyright (c) 2019-present The Bitcoin Core developers
2// Distributed under the MIT software license, see the accompanying
3// file COPYING or http://www.opensource.org/licenses/mit-license.php.
4
5#ifndef BITCOIN_INDEX_DISKTXPOS_H
6#define BITCOIN_INDEX_DISKTXPOS_H
7
8#include <flatfile.h>
9#include <serialize.h>
10
11struct CDiskTxPos : public FlatFilePos
12{
13    uint32_t nTxOffset{0}; // after header
14
15    SERIALIZE_METHODS(CDiskTxPos, obj)
16    {
17        READWRITE(AsBase<FlatFilePos>(obj), VARINT(obj.nTxOffset));
18    }
19
20    CDiskTxPos(const FlatFilePos& blockIn, uint32_t nTxOffsetIn) : FlatFilePos{blockIn.nFile, blockIn.nPos}, nTxOffset{nTxOffsetIn} {
21    }
22
23    CDiskTxPos() = default;
24};
25
26#endif // BITCOIN_INDEX_DISKTXPOS_H
27

FILE GUIDE · KEY SECTIONS

A transaction position relative to a stored block

CDiskTxPos extends a flat-file location with an offset after the block header. It is a storage locator, not a transaction identifier or an on-chain field.

Line 11 ↗

Combine the block location with a transaction offset

The base supplies file number and block data position; nTxOffset counts additional bytes after the header. Readers using this representation read the header and then seek by that offset. This differs from the newer txindex BlockTxPosition offset measured from the start of the whole block.

Line 15 ↗

Use the shared file-location encoding plus a varint

Serialization writes the inherited FlatFilePos and variable-length transaction offset. A decoded position only says where to look; a reader must still open retained data, deserialize it and check that the transaction is the requested one.

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Bitcoin Core source © its contributors, distributed under the MIT license. Original notices and bundled third-party licenses are retained in the source tree.