SDL_IN_BYTECAP(3)

💖 SDL_IN_BYTECAP(3) 💖

okay bestie, welcome to the SDL3 FUNCTIONS corner of the manual, where we're talking about SDL_IN_BYTECAP — a lil macro that annotates function params with input buffer size. no cap, that's literally all it does, and it's iconic for it. 🎀

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✨ NAME ✨

SDL_IN_BYTECAP — macro that annotates function params with input buffer size. that's the whole vibe. 🦋

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🌸 SYNOPSIS 🌸

#include <SDL3/SDL_stdinc.h>

#define SDL_IN_BYTECAP(x) _In_bytecount_(x)

copy that include exactly, bestie, character for character. 💅

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🫶 DESCRIPTION 🫶

so here's the tea. say we wanted to annotate memcpy, right? like this:

void *memcpy(void *dst, SDL_IN_BYTECAP(len) const void *src, size_t len);

what this is doing is noting that src should be len bytes in size, and that it's only read by the function. that's it, that's the note. 📝

and because that note is there, the compiler or other analysis tools can warn you when this doesn't appear to be the case. like a lil friend going "bestie… that buffer is NOT len bytes, I'm gonna need you to look at that". 🔍✨

and on compilers without this annotation mechanism? it's defined to nothing. fr fr, it just vanishes. poof. 🫥 the code still compiles, the annotation just doesn't exist. no drama, no warnings, no vibe check.

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⭐ AVAILABILITY ⭐

this macro is available since SDL 3.2.0. so if you're on something older, it's giving… not here yet. 💀

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and that's the whole page, periodt. thanks for reading, you ate. 👑

signing off from the Simple Directmedia Layer besties — this was SDL 3.4.18, page SDL_IN_BYTECAP(3). mwah, take care of your buffers. 💖🌈