al_ustr_prev(3)

✨ al_ustr_prev(3) ✨

okay bestie so this is a page from the Allegro 5 API reference manual (the Library Functions Manual, if we're being fancy 💅) and it's about a tiny little function that walks backwards through a UTF-8 string. it's giving "reverse scavenger hunt" energy and honestly? kind of iconic.

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🌸 SYNOPSIS 🌸

#include <allegro5/allegro.h>

bool al_ustr_prev(const ALLEGRO_USTR *us, int *pos)

literally just one include and one function call, we love a low-effort queen 👑

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🦋 DESCRIPTION 🦋

so here's the vibe: al_ustr_prev finds the byte offset of the previous code point in the string, the one sitting right before *pos. and the slayest part? *pos does not have to be at the beginning of a code point — it can be chilling anywhere, no pressure 💖

it returns true on success, and the value pointed to by pos gets updated to the found offset. cute, right?

but if *pos was already at the end of the string, it returns false and *pos stays totally unmodified. respectful king, doesn't touch what it doesn't need to 🫶

⚠️ heads up bestie: this function just looks for an appropriate byte. it does not check whether the found offset is actually the beginning of a valid code point. so if you're working with possibly invalid UTF-8 strings, it could skip over some invalid bytes. no cap, watch out for that 😭

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👑 SEE ALSO 👑

• al_ustr_next(3) — the forward-walking sibling, go show it some love 💜

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~ and that's the whole page, bestie ~ this gem comes to you from the Allegro reference manual and was dated according to the footer on the original page (source/version + date live right there in the footer, iykyk 🎀). now go forth and iterate backwards with main character energy ✨💅🌈