Provided by: libsdl3-doc_3.2.10+ds-1_all 

NAME
SDL_WINDOWPOS_ISUNDEFINED - A macro to test if the window position is marked as "undefined."
HEADER FILE
Defined in SDL3/SDL_video.h
SYNOPSIS
#include "SDL3/SDL.h" #define SDL_WINDOWPOS_ISUNDEFINED(X) (((X)&0xFFFF0000) == SDL_WINDOWPOS_UNDEFINED_MASK)
AVAILABILITY
This macro is available since SDL 3.2.0. Simple Directmedia Layer SDL 3.2.10 SDL_WINDOWPOS_ISUNDEFINED(3)