BIO_F_NULL(3ossl)

💅 BIO_f_null — the null filter (yes, it's exactly what it sounds like)

okay so real talk, this page is from the OpenSSL fam, section 3ossl, and bestie… it's a short one. But we're gonna give it the full main-character treatment anyway because every page deserves love. 🎀

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✨ NAME ✨

BIO_f_null — the null filter. That's it. That's the whole vibe. 🦋

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✨ SYNOPSIS ✨

#include <openssl/bio.h>

const BIO_METHOD *BIO_f_null(void);

like, look at her. so minimal. so unbothered. 💅

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✨ DESCRIPTION ✨

BIO_f_null() returns the null filter BIO method. And what is that, you ask? It's a filter BIO that does nothing. Literally nothing. Not a single thing. 🫶

Every single request that comes into a null filter BIO gets passed straight through to the next BIO in the chain — no notes, no edits, no commentary. Which means the tea is: a BIO chain that contains a null filter BIO behaves exactly as though that BIO was never even there. ghost behavior fr fr 👻

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✨ NOTES ✨

As may be apparent… a null filter BIO is not particularly useful. 😭 like yeah. that's the note. that's the whole note. iconic honestly 💀

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✨ RETURN VALUES ✨

BIO_f_null() returns the null filter BIO method. (yes, that's the return value. she gives you the method. that's her job.) ⭐

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✨ COPYRIGHT ✨

Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.

Licensed under the Apache License 2.0 (the "License"). You may not use this file except in compliance with the License. You can obtain a copy in the file LICENSE in the source distribution or at https://www.openssl.org/source/license.html.

bestie please actually read the license, it's not a vibe to skip it 🙈

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okay that's the whole page, no cap. this one's from OpenSSL 3.5.6, dated 2026-04-07 — go drink some water and chain your BIOs responsibly 💖✨🌸