SDL_HINT_CUDA_DEVICE environment variable

Greetings,

It has been suggested by users of various software that leverage SDL that one use the following environment variables to run headless and/or off-screen on a specific GPU, where GPU_INDEX is the index of the device, e.g. SDL_VIDEODRIVER=offscreen SDL_HINT_CUDA_DEVICE=2 ./myOpenGLBasedApp

While SDL_VIDEODRIVER exists in the SDL 2.0.9 source, SDL_HINT_CUDA_DEVICE does not, yet a google search shows the latter being suggested for use on multiple webforums. Was this variable removed in SDL 2.0 or is it somehow automatically generated and not hardcoded into the source? I ask because, for ‘C+G’ (compute + graphics) jobs in Linux seem to run on device 0 regardless of what index SDL_HINT_CUDA_DEVICE is set to.

Thanks

Update: this environment variable apparently exists in Epic’s fork of SDL2.