[TUHS] Source code abundance?

[Angelo Papenhoff]

On 06/03/17, Clem Cole wrote:
> On Mon, Mar 6, 2017 at 11:20 AM, Joerg Schilling <schily at schily.net> wrote:
> 
> >
> > The kernel definitely looks like it was written from scratch.
> >
> > The fact that there are functions like "issig()" make it obvious that the
> > authors did have access to at least the V6 kernel via the Lions book.
> 
> 
> I can say for a fact that is not how it was.   AIX was a port starting
> with AT&T code originally targeted to run on DEC and Intel Systems.
> 
> As I said previously when I ran down the history of AIX, the developers had
> AT&T licenses.   As I was reminded in an off line discussion with one of
> the IBM guys when I was checking to make sure, ISC did the original 386
> port for all of AT&T, Intel and IBM (one port - 3 checks).  ISC also
> started the AIX port, with a number of the folks moving to LCC which was a
> step I left out in my previous email sorry, since it was implied when I
> said they started with that AT&T 386 stuff (which AT&T got from ISC).
> Bottom line.... it was not a rewrite, it was always a port.
> 
> ...
> 
> Companies like DEC, HP and IBM start working with one version of the kernel
> or worse yet, the command system and enhance it as they need.   But time
> moves forward and their version and the rest of the world start to become
> different (branch/fork).   Linux has been mostly able to keep the kernel
> the same, but not the command system.

I find this hard to believe. Of course code evolves, but I don't really
see anything that looks like original UNIX code in AIX 4.1.3. I would
expect at least a slight semblance. Had they really replaced (almost?)
all code by the time of AIX 4?

aap