stringprep_ucs4_to_utf8(3)

💖 stringprep_ucs4_to_utf8(3) 💖

okay bestie, welcome to the libidn corner of the man pages 🎀 this one is a lil function called stringprep_ucs4_to_utf8, and no cap, it's actually so useful — it's the little glow-up machine that takes your chunky 32-bit UCS-4 text and turns it into a cute lil UTF-8 string ✨

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🌸 NAME 🌸

stringprep_ucs4_to_utf8 — it's an API function, periodt 💅

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✨ SYNOPSIS ✨

#include <stringprep.h>

char * stringprep_ucs4_to_utf8(const uint32_t * str, ssize_t len, size_t
* items_read, size_t * items_written);

like, that's the whole vibe right there 🫶

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🦋 ARGUMENTS 🦋

• const uint32_t * str — a UCS-4 encoded string. the main character of this whole operation 👑
• ssize_t len — the maximum length of str that we're actually gonna use. and here's the tea: if len < 0, then the string is terminated with a 0 character. so negative len = "just go till the null, girl" 💀
• size_t * items_read — a location to store the number of characters read. or NULL if you literally don't care. your call 🍓
• size_t * items_written — a location to store the number of bytes written, or NULL. and heads up: the value stored here does not include the trailing 0 byte. not the null, just the real ones 💅

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🌈 DESCRIPTION 🌈

So what does it DO? It converts a string from a 32-bit fixed width representation (that's UCS-4, the thicc one) into UTF-8 🧚 and the result is terminated with a 0 byte, so it's nice and tidy at the end.

Return value: a pointer to a newly allocated UTF-8 string. and bestie, listen — this value must be deallocated by the caller. that memory is yours to free, nobody's gonna do it for you, it's giving main character responsibility 😭

If an error occurs, NULL will be returned. so like, always vibe check your return value fr fr 🙈

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💀 REPORTING BUGS 💀

Found a bug? Not me being dramatic but like, please tell the devs 🫶

Report bugs to <help-libidn@gnu.org>.

General guidelines for reporting bugs: https://www.gnu.org/gethelp/

GNU Libidn home page: https://www.gnu.org/software/libidn/

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👑 COPYRIGHT 👑

Copyright © 2002-2026 Simon Josefsson.

Copying and distribution of this file, with or without modification, are permitted in any medium without royalty provided the copyright notice and this notice are preserved. (iconic behaviour honestly ✨)

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💜 SEE ALSO 💜

The full documentation for libidn is maintained as a Texinfo manual. If the info and libidn programs are properly installed at your site, the command

info libidn

should give you access to the complete manual. obsessed 💅

As an alternative you may obtain the manual from:

https://www.gnu.org/software/libidn/manual/

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and that's the whole page, bestie!! this was stringprep_ucs4_to_utf8(3) from libidn 1.44 🌸 go forth and convert your UCS-4 to UTF-8, slay, and remember to free() that pointer 🎀✨🦋