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

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1// Copyright (c) 2016-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#include <util/rbf.h>
6
7#include <primitives/transaction.h>
8
9#include <vector>
10
11bool SignalsOptInRBF(const CTransaction &tx)
12{
13    for (const CTxIn &txin : tx.vin) {
14        if (txin.nSequence <= MAX_BIP125_RBF_SEQUENCE) {
15            return true;
16        }
17    }
18    return false;
19}
20

FILE GUIDE · KEY SECTIONS

Detecting explicit replace-by-fee sequence signaling

SignalsOptInRBF scans transaction inputs for the sequence-number threshold declared in util/rbf.h.

Line 11 ↗

One signaling input is sufficient

The first input whose sequence is at most MAX_BIP125_RBF_SEQUENCE makes the function return true; no such input returns false, including an empty input vector. This is only a signaling test. It does not evaluate replacement fees, conflicts, inherited status or whether the local mempool will accept a replacement.

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