RAND_BYTES(3)

🎀 RAND_BYTES(3) 🎀

okay so bestie, you found the RAND_BYTES(3) page — it lives in the Library Functions Manual corner of the universe, and honestly? it's giving "vintage". let's get into it 💅

---

✨ NAME ✨

RAND_bytes, RAND_pseudo_bytes — generate random data 🎲✨

---

🌈 SYNOPSIS 🌈

this one's from the library “libcrypto”, and you'll be pulling in:

#include <openssl/rand.h>

and here are the two icons themselves, exactly as written:

int
RAND_bytes(unsigned char *buf, int num);

int
RAND_pseudo_bytes(unsigned char *buf, int num);

---

💖 DESCRIPTION 💖

🚨 heads up bestie: these functions are deprecated and only retained for compatibility with legacy application programs. use arc4random_buf(3) instead. periodt. 💀

RAND_bytes() puts num cryptographically strong pseudo-random bytes into buf. 🔥 like, actually strong. main character randomness.

RAND_pseudo_bytes() puts num pseudo-random bytes into buf. here's the tea though — pseudo-random byte sequences generated by RAND_pseudo_bytes() will be unique if they're of sufficient length, but they are not necessarily unpredictable. 😭 so basically: fine for non-cryptographic purposes and for certain purposes in cryptographic protocols, but usually not for key generation etc. do not come for me if you use it for keys, i warned you. 🙈

---

🦋 RETURN VALUES 🦋

• RAND_bytes() returns 1. ✨
• RAND_pseudo_bytes() returns 1. ✨

yes both. always 1. slay, consistency. 👑

---

🌸 HISTORY 🌸

RAND_bytes() first appeared in SSLeay 0.5.1 and has been available since OpenBSD 2.4. It has a return value since OpenSSL 0.9.5 and OpenBSD 2.7. 🕰️

RAND_pseudo_bytes() first appeared in OpenSSL 0.9.5 and has been available since OpenBSD 2.7. 🫶

---

okay that's the whole page, no notes 💜 this lil doc is brought to you by Debian, dated June 8, 2025 — shoutout to the packagers, they ate and left no crumbs 🎀✨ bye bestie, go use arc4random_buf(3) i'm begging 🧚