Use native shell functions in std libraries to improve performance?

Use native shell functions in std libraries to improve performance? This could be done like in [os.Shell](https://github.com/monstermichl/TypeShell/blob/d86389ac4aa4453df17531982c223c3cf1474974/std/os.tsh#L8) with the help of *os.Shell* to determine the shell first and then use the appropriate OS commands.