I don't think anybody
was even thinking of porting any of
the *BSD to IBM mainframes till much later, am I right?
No. BSD
was very much on IBM's radar in the late 1970s and 1980s.
Long before
Linus released Linux into the wild in 1990 for the
>>386<< much less any other ISA, IBM had been
shipping as a product AIX/370 (and AIX/PS2 for the 386);
which we developed at Locus for them. The user-space was
mostly System V, the kernel was based on BSD (4.1
originally) pluis a great deal of customization, including
of course the Locus OS work, which IBM called TCF - the
transparent computing facility. It was very cool you
could cluster 370s and PS/2 and from >>any<<
node run a program of either ISA. It has been well
discussed in this forum, previously.
A for
AIX/370 a quick history which Charlie can fill in more
from the IBM side, was that in the last 60s and early 70s,
IBM had a strange hold on the education/research market
with the S/360; but lost it because of the lack of
timesharing to DEC and PDP-10 based systems as IBM was
more and more focused on the commercial sector where there
was much more money to be made. But ... there was a
drive in the IBM educational/research team to be able to
reenter that market and Locus was hired to develop AIX/370
(and later PS2) as it was felt that UNIX was considered an
important offering for those customers. After it was
released as a product, it turned out purchasing AIX/370
was exceedingly difficult (for a number of reasons),
although it was extremely well received by those that ran
it, but getting it was difficult. In fact, I have been
told by folks that there at the time, that using TCF was
an important feature here at Intel for the success of the
simulation for the 486 and Pentium.
Again, Charlie
can tell you the history but IBM also developed AIX for the
RS/6000 which was the same OS (only
different) from
IBM Austin (no TCF,
but supported DS which was cool in its own right).
Locus was actually contracted to develop a
UNIX subsystem for the AS/400 also, but I'm not sure if
that ever shipped. I had left Locus and had gone to DEC by
then.