SDL_hid_read(3)

📦
version 3.4.18 · 9 versions
, in fedora 43, fedora 44

💖 SDL_hid_read(3) 💖

okay bestie, so this one lives in the SDL3 FUNCTIONS section of the manual, and it's literally about reading an Input report off a HID device. that's the whole vibe. let's get into it 🫶

✨ NAME ✨

SDL_hid_read — Read an Input report from a HID device.

like... that's it. that's the job. it reads an Input report. from a HID device. no cap. 🎀

✨ SYNOPSIS ✨

#include <SDL3/SDL_hidapi.h>

int SDL_hid_read(SDL_hid_device *dev, unsigned char *data, size_t length);

ok so you gotta pull in the header first, #include <SDL3/SDL_hidapi.h>, and then you've got this little icon of a function right here. slay. 💅

✨ DESCRIPTION ✨

so here's the tea, bestie: Input reports get returned to the host through the INTERRUPT IN endpoint. that's the pipe they come down, that's just how it is. 🌈

and here's the part that gets people — the first byte will contain the Report number if the device uses numbered reports. if it doesn't? then it doesn't. conditional, periodt. 💀

✨ FUNCTION PARAMETERS ✨

  • dev — a device handle returned from SDL_hid_open(). you gotta have one of these already, like you can't just show up with nothing. 🙈
  • data — a buffer to put the read data into. it's your lil container. the data goes in here. 🍓
  • length — the number of bytes to read. important note: for devices with multiple reports, make sure to read an extra byte for the report number. don't forget it, that extra byte is load-bearing fr fr. ✨

✨ RETURN VALUE ✨

ok so this is the part where you actually read the receipt:

  • returns the actual number of bytes read — so it might not be the full length you asked for, keep that in mind 👑
  • returns -1 on failure. when that happens, call SDL_GetError() for more information. she'll tell you what went wrong 💜
  • and if no packet was available to be read and the handle is in non-blocking mode, this function returns 0.
⚠️ lowkey crucial: 0 and -1 mean completely different things here. 0 = nothing was there yet, you're in non-blocking mode, all good. -1 = something actually went wrong. do not mix these up bestie, it's giving bug energy. 😭

✨ AVAILABILITY ✨

This function is available since SDL 3.2.0. so if you're on anything older than that, it's simply not giving. upgrade your SDL, bestie. 🌸

🦋 sign-off 🦋

this page came to you from Simple Directmedia Layer, and the version floating around up there is SDL 3.4.18, dated alongside SDL_hid_read(3). go read some reports, you're gonna ate this one. mwah 💖✨🎀

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