What UNIX does UTS look like?

[Charles Howell]

Is UTS a "look-alike" for one specific incarnation of UNIX  (e.g.
System  V,  BSD  4.2,  etc.)  or  is it a "blend" of various UNIX
systems?  I'm not so much interested in  the  "Chapter  1"  stuff
(tools)  as  I  am  in  chapters  2 and 3; how much work would be
required to port a tool written for BSD 4.2 ?  Does  UTS  run  on
top of VM?

Thanks,
    Chuck Howell