addseverity(3)

✨ addseverity(3) ✨

okay bestie, gather round, because we're reading a page from the Library Functions Manual and it's lowkey iconic 💖

🌸 NAME 🌸

addseverity — introduce new severity classes

📚 LIBRARY 📚

Standard C library (libc, -lc)

🎀 SYNOPSIS 🎀

#include <fmtmsg.h>

int addseverity(int severity, const char *s);

🦋 Feature Test Macro Requirements for glibc (see feature_test_macros(7)) 🦋

addseverity():

• Since glibc 2.19:
  • _DEFAULT_SOURCE
• glibc 2.19 and earlier:
  • _SVID_SOURCE

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💅 DESCRIPTION 💅

so basically, this function is your little backstage pass to make new severity classes ✨. These are the classes that the severity argument of the fmtmsg(3) function can point at. Like, fmtmsg(3) needs to know what vibe a message is giving, and this is how you teach it.

out of the box? fmtmsg(3) only knows how to print messages for severity 0-4, with the strings (none), HALT, ERROR, WARNING, and INFO. that's it. that's the whole default roster 🫶

so what this call does is attach the string s you hand it to the numeric value severity you hand it. matching set, slay.

and if s is NULL? then the severity class with the numeric value severity gets removed. bye bestie 👋

🚨 okay important: you cannot overwrite or remove one of the default severity classes. they're protected. main character privileges, iykyk.

and one more thing — the severity value must be nonnegative. no negatives allowed, periodt.

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🔥 RETURN VALUE 🔥

• on success you get MM_OK back 💖
• on error you get MM_NOTOK back 💀

possible errors include: out of memory, or an attempt to remove a nonexistent or default severity class.

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👑 ATTRIBUTES 👑

for an explanation of the terms used in this section, see attributes(7).

• Interface: addseverity()
• Attribute: Thread safety
• Value: MT-Safe

so yeah, she's MT-Safe, we love a thread-safe queen 🌈

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⭐ STANDARDS ⭐

GNU.

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🌸 HISTORY 🌸

glibc 2.1. System V.

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💜 NOTES 💜

you can also add new severity classes by setting the environment variable SEV_LEVEL. two paths to the same glow-up, no cap ✨

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🧚 SEE ALSO 🧚

• fmtmsg(3)

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and that's the whole page, bestie!! this was Linux man-pages 6.20, dated 2026-02-08, and she ate, fr fr 💅🎀🦋