[Info-vax] What is a "real" Unix ?

[gah4]

On Monday, September 4, 2023 at 5:15:26 AM UTC-7, Simon Clubley wrote:

(snip)

> In that case, what is a "real" Unix ? 

> Is it something that implements a set of user-visible APIs and certain 
> behaviour within its kernel (fork() semantics for example) ? 
 

There used to be a story about George Washington's axe.
(The one he cut down the cherry tree with.)

After many year, two new blades and three new handles, it is still GW's axe.

So, starting with BSD Unix, and one by one replacing Unix copyright code with
BSD replacements, is there some point that it isn't Unix anymore?