Provided by: libsdl3-doc_3.2.20+ds-2_all 

NAME
SDL_GetJoystickSerial - Get the serial number of an opened joystick, if available.
SYNOPSIS
#include <SDL3/SDL_joystick.h>
const char * SDL_GetJoystickSerial(SDL_Joystick *joystick);
DESCRIPTION
Returns the serial number of the joystick, or NULL if it is not available.
FUNCTION PARAMETERS
joystick
the SDL_Joystick obtained from SDL_OpenJoystick().
RETURN VALUE
Returns the serial number of the selected joystick, or NULL if unavailable.
AVAILABILITY
This function is available since SDL 3.2.0.
Simple Directmedia Layer SDL 3.2.20 SDL_GetJoystickSerial(3)