SSL_SESSION_REUSED(3ossl)

📦
version 15.1 · 3 versions
, in freebsd 15.1

💅 SSL_SESSION_REUSED — the "did we just reuse that session or what" check 💅

okay bestie, so this is from the OpenSSL squad (the 3ossl corner of manual-page-land, iykyk ✨), and it's genuinely one of the simplest little functions you'll ever meet. It's giving "one job, does it well" energy. Let's get into it 🫶

✨ NAME ✨

SSL_session_reused — literally just queries whether a reused session was negotiated during the handshake. That's it. That's the whole vibe check 🌸

🦋 SYNOPSIS 🦋

#include <openssl/ssl.h>

int SSL_session_reused(const SSL *ssl);

so you include the header, you call the function on a const SSL *, and you get back an int. iconic, no notes 💖

🎀 DESCRIPTION 🎀

okay so the actual job description: query whether a reused session was negotiated during the handshake. That's the entire thing. It's a yes-or-no girlie in function form 👑

🔥 NOTES 🔥

ngl this is the part where it gets cute, so pay attention 🧚

During the negotiation, a client can propose to reuse a session. The server then looks up the session in its cache. If both client and server agree on the session, it will be reused — and a flag gets set that can be queried by the application. That flag is exactly what this function is peeking at. slay 💅

so like… the whole handshake is a little group-chat negotiation, the client's like "hey can we reuse this one", the server checks the cache, everyone agrees, session gets reused, flag gets set, and then your app can ask "hey was that a reuse situation?" and SSL_session_reused is the one who answers. no cap 🔥

⭐ RETURN VALUES ⭐

bestie there are exactly two possible answers and neither of them is a mystery:

  • 0 — a new session was negotiated. fresh start, main character energy ✨
  • 1 — a session was reused. the reunion episode 🎀

that's the whole return value situation, fr fr 🦋

👑 SEE ALSO 👑

go read those if you want the full lore, iykyk 💜

Copyright 2001-2016 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 before you go copy-pasting stuff, it's giving "read the room" but for legal text 😭

and that's the page! 🍓 this little beauty is from OpenSSL 3.5.6, dated 2026-04-07, and it goes out to the whole SSL_SESSION_REUSED(3ossl) crew. mwah 💋💖

📦 where this page comes from