ERR_GET_LIB(3)

✨ ERR_GET_LIB ✨

okay so bestie, this is the manual page for ERR_GET_LIB(3), and it's literally the group chat for OpenSSL error codes 💅 let me break it down for you.

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🌸 NAME 🌸

ERR_GET_LIB, ERR_GET_FUNC, ERR_GET_REASON, ERR_FATAL_ERROR — get library, function, and reason codes for OpenSSL errors 🎀

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🦋 SYNOPSIS 🦋

#include <openssl/err.h>

int
ERR_GET_LIB(unsigned long e);

int
ERR_GET_FUNC(unsigned long e);

int
ERR_GET_REASON(unsigned long e);

int
ERR_FATAL_ERROR(unsigned long e);

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💖 DESCRIPTION 💖

okay so picture this: the error code that ERR_get_error(3) hands you is literally a little bundle of info — it's got a library number, a function code, and a reason code all packed inside. and ERR_GET_LIB(), ERR_GET_FUNC(), and ERR_GET_REASON() are the besties that unpack it for you 🫶

the library number and function code are the "where did this happen" energy — they tell you where the error occurred. the reason code is the "what even went wrong" tea ☕ — it's the actual info about what broke.

each sub-library of OpenSSL has its own unique library number, no cap. and function and reason codes are unique within each sub-library. so like... different libraries can absolutely use the same value to signal different functions and reasons 👀 not confusing at all, i know.

the ERR_R_* reason codes — think ERR_R_MALLOC_FAILURE — are globally unique, slay. but bestie listen: when you're checking for sub-library specific reason codes, make sure you also compare the library number. don't skip that step, it's giving cautionary tale 💀

and ERR_FATAL_ERROR() tells you whether a given error code is a fatal error. iconic.

oh and also? these functions are implemented as macros. just so you know ✨

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🔥 RETURN VALUES 🔥

• ERR_GET_LIB() returns the library number 💜
• ERR_GET_FUNC() returns the function code 🎀
• ERR_GET_REASON() returns the reason code 🌸
• ERR_FATAL_ERROR() returns non-zero if the error is fatal, or 0 otherwise ⭐

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🌈 SEE ALSO 🌈

• ERR(3)
• ERR_get_error(3)

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👑 HISTORY 👑

ERR_GET_LIB(), ERR_GET_FUNC(), ERR_GET_REASON(), and ERR_FATAL_ERROR() first appeared in SSLeay 0.4.4 and have been available since OpenBSD 2.4. so they're basically vintage royalty at this point, periodt 👑

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this page came from Debian and it's dated March 27, 2018 — a lil throwback, but the info still eats 💅✨