[ale] Mac's version of BSD

[Drifter]

I am essentially clueless about the underpinnings of a Mac.
But, given the recent discussions on failing hard drives, I couldn't help 
but remember my wife's recent PAIN -- the HD in her Mac laptop died and 
that's when she discovered that her backup drive had died a week or so 
earlier.  (She hadn't understood the error messages she was getting.)
Two new hard drives later she is trying to recover what she can.

So this afternoon I checked and the command <smartctl> is not on her 
machine.  Is it available?  If so, what is the download/install procedure?

Sean