Ubuntu Manpages

SDL_PRIx64

A printf-formatting string for a Uint64 value as lower-case hexadecimal.

#include <SDL3/SDL_stdinc.h>
#define SDL_PRIx64 "llx"

Use it like this:

SDL_Log("There are %" SDL_PRIx64 " bottles of beer on the wall.", bottles);
    

This macro is available since SDL 3.2.0.