AL_REGISTER_BITMAP_IDENTIFIER(3)

💅 al_register_bitmap_identifier — Allegro 5 API 🎀

ok so this page lives in the Library Functions Manual section of the Allegro docs, and bestie, it's short but it matters. Let's get into it ✨

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✨ NAME ✨

al_register_bitmap_identifier — Allegro 5 API 🦋

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🌸 SYNOPSIS 🌸

#include <allegro5/allegro.h>

bool al_register_bitmap_identifier(const char *extension,
   bool (*identifier)(ALLEGRO_FILE *f))

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💖 DESCRIPTION 💖

So here's the vibe: you're registering an identify handler for al_identify_bitmap(3). Basically you hand over a function, and that function gets used to detect files for whatever extension you named. Iconic little tag-team situation 🤝

Your handler gets called with a single argument of type ALLEGRO_FILE(3) — that's a file handle, already opened for reading, sitting right at the first byte of the file. Ready to go, no setup needed 💅

Now, the handler's whole job is a vibe check: it should try to read as few bytes as possible to safely determine whether the file contents actually correspond to the type with that extension. If yes → return true. If no → return false. That's it, that's the job 🫶

⚠️ Important caveats, no cap: the file handle must not be closed by your handler. You also don't need to reset it back to the beginning — so like, don't stress about rewinding, just don't close it either 😭

A couple more deets about the arguments:

• The extension should include the leading dot (.) character. And good news — it gets matched case-insensitively 👑
• The identifier argument can be NULL if you want to unregister an entry. Ghosting it, essentially 🙈

Return value time: true on success, false on error. Also — and this is the little gotcha — it returns false if you try to unregister an entry that doesn't exist 🧚

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⭐ SINCE ⭐

5.1.12 — been here since the old days, fr fr 💜

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🌈 SEE ALSO 🌈

• al_identify_bitmap(3) — the main character this one's supporting 🎀

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okay that's the whole page! this little beauty comes straight out of the Allegro reference manual, so shoutout to the Allegro gang for keeping al_register_bitmap_identifier(3) documented and slaying 💖✨ go forth and identify those bitmaps bestie 🦋💅