Yes; I'm aware, but for some environments writting a custom shell as the one for SDF would be an easier task. Or maybe a really restricted "ash" called "rash" -

Yes; I'm aware, but for some environments writting a custom shell as the one for SDF would be an easier task. Or maybe a really restricted "ash" called "rash" -because it is- with maybe autocomplete and that's it. Hardcoded $PATH and the like.