al_ustr_newf(3alleg5)

✨ al_ustr_newf ✨

okay so bestie, this one's from the Allegro 5 API manual (yes, 3alleg5, iykyk) and it's genuinely one of the most useful little functions in the whole string game 💖

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🌸 SYNOPSIS 🌸

#include <allegro5/allegro.h>

ALLEGRO_USTR *al_ustr_newf(const char *fmt, ...)

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🦋 DESCRIPTION 🦋

It makes you a brand new string, and it builds that string out of a printf-style format string. That's the whole vibe. You hand it a format, it hands you back a fresh ALLEGRO_USTR. iconic behavior honestly 💅

Now. The notes. Because there are notes. And the notes are important, no cap 🚨

• The %s specifier takes C string arguments, NOT ALLEGRO_USTRs. So if you wanna pass an ALLEGRO_USTR as a parameter you gotta go through al_cstr(3alleg5), and it must be NUL terminated. And like, be careful bestie: if the string contains an embedded NUL byte, everything from that byte onwards is just ignored. Gone. Poof. 💀
• The %c specifier outputs a single byte, not the UTF-8 encoding of a code point. So it's only usable for ASCII characters (value <= 127), OR if you literally and intentionally mean to output byte values from 128–255. That's it, that's the range.

So how do you actually put a code point's UTF-8 encoding in there? 🧚 You encode it into a memory buffer using al_utf8_encode(3alleg5), and then you use the %s specifier. And remember to NUL terminate that buffer. Do not forget. I'm watching. 🙈

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⭐ SEE ALSO ⭐

• al_ustr_new(3alleg5)
• al_ustr_appendf(3alleg5)

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and that's the page, bestie!! go forth and format your little heart out 🎀✨

this has been the Allegro reference manual's page for al_ustr_newf(3alleg5) — same page, same name, forever and always 🫶💜