SDL_GetPrimaryDisplay - Man Page

Defined in SDL3/SDL_video.h

#include "SDL3/SDL.h"

SDL_DisplayID SDL_GetPrimaryDisplay(void);

( SDL_DisplayID ) Returns the instance ID of the primary display on success or 0 on failure; call SDL_GetError () for more information.

This function should only be called on the main thread.

This function is available since SDL 3.2.0.

·(3), SDL_GetDisplays(3)