<s>
Ultrix	B-Operating_System
(	O
officially	O
all-caps	O
ULTRIX	B-Operating_System
)	O
is	O
the	O
brand	O
name	O
of	O
Digital	O
Equipment	O
Corporation	O
's	O
(	O
DEC	O
)	O
discontinued	O
native	O
Unix	B-Application
operating	I-Application
systems	I-Application
for	O
the	O
PDP-11	B-Device
,	O
VAX	B-Device
,	O
MicroVAX	B-Device
and	O
DECstations	B-Device
.	O
</s>
<s>
The	O
initial	O
development	O
of	O
Unix	B-Application
occurred	O
on	O
DEC	O
equipment	O
,	O
notably	O
DEC	O
PDP-7	B-Device
and	O
PDP-11	B-Device
(	O
Programmable	O
Data	O
Processor	O
)	O
systems	O
.	O
</s>
<s>
Later	O
DEC	O
computers	O
,	O
such	O
as	O
their	O
VAX	B-Device
,	O
also	O
offered	O
Unix	B-Application
.	O
</s>
<s>
The	O
first	O
port	O
to	O
VAX	B-Device
,	O
UNIX/32V	B-Operating_System
,	O
was	O
finished	O
in	O
1978	O
,	O
not	O
long	O
after	O
the	O
October	O
1977	O
announcement	O
of	O
the	O
VAX	B-Device
,	O
for	O
which	O
–	O
at	O
that	O
time	O
–	O
DEC	O
only	O
supplied	O
its	O
own	O
proprietary	B-Application
operating	O
system	O
,	O
VMS	B-Operating_System
.	O
</s>
<s>
DEC	O
's	O
Unix	B-Application
Engineering	O
Group	O
(	O
UEG	O
)	O
was	O
started	O
by	O
Bill	O
Munson	O
with	O
Jerry	O
Brenner	O
and	O
Fred	O
Canter	O
,	O
both	O
from	O
DEC	O
's	O
Customer	O
Service	O
Engineering	O
group	O
,	O
Bill	O
Shannon	O
(	O
from	O
Case	O
Western	O
Reserve	O
University	O
)	O
,	O
and	O
Armando	O
Stettner	O
(	O
from	O
Bell	O
Labs	O
)	O
.	O
</s>
<s>
Under	O
Canter	O
's	O
direction	O
,	O
UEG	O
released	O
V7M	O
,	O
a	O
modified	O
version	O
of	O
Unix	B-Operating_System
7th	I-Operating_System
Edition	I-Operating_System
(	O
q.v.	O
</s>
<s>
In	O
1988	O
The	O
New	O
York	O
Times	O
reported	O
Ultrix	B-Operating_System
POSIX-compliant	O
.	O
</s>
<s>
Shannon	O
and	O
Stettner	O
worked	O
on	O
low-level	O
CPU	B-General_Concept
and	O
device	O
driver	O
support	O
initially	O
on	O
UNIX/32V	B-Operating_System
but	O
quickly	O
moved	O
to	O
concentrate	O
on	O
working	O
with	O
the	O
University	O
of	O
California	O
,	O
Berkeley	O
's	O
4BSD	B-Operating_System
.	O
</s>
<s>
Berkeley	O
's	O
Bill	O
Joy	O
came	O
to	O
New	O
Hampshire	O
to	O
work	O
with	O
Shannon	O
and	O
Stettner	O
to	O
wrap	O
up	O
a	O
new	O
BSD	B-Operating_System
release	O
.	O
</s>
<s>
UEG	O
's	O
machine	O
was	O
the	O
first	O
to	O
run	O
the	O
new	O
Unix	B-Application
,	O
labeled	O
4.5BSD	O
as	O
was	O
the	O
tape	O
Bill	O
Joy	O
took	O
with	O
him	O
.	O
</s>
<s>
Stettner	O
stayed	O
at	O
DEC	O
and	O
later	O
conceived	O
of	O
and	O
started	O
the	O
Ultrix	B-Operating_System
project	O
.	O
</s>
<s>
Shortly	O
after	O
IBM	O
announced	O
plans	O
for	O
a	O
native	O
UNIX	B-Application
product	O
,	O
Stettner	O
and	O
Bill	O
Doll	O
presented	O
plans	O
for	O
DEC	O
to	O
make	O
a	O
native	O
VAX	B-Device
Unix	B-Application
product	O
available	O
to	O
its	O
customers	O
;	O
DEC-founder	O
Ken	O
Olsen	O
,	O
agreed	O
.	O
</s>
<s>
DEC	O
's	O
first	O
native	O
UNIX	B-Application
product	O
was	O
V7M	O
(	O
for	O
modified	O
)	O
or	O
V7M11	O
for	O
the	O
PDP-11	B-Device
and	O
was	O
based	O
on	O
version	O
of	O
UNIX	B-Operating_System
7th	I-Operating_System
Edition	I-Operating_System
from	O
Bell	O
Labs	O
.	O
</s>
<s>
V7M	O
,	O
developed	O
by	O
DEC	O
's	O
original	O
Unix	B-Application
Engineering	O
Group	O
(	O
UEG	O
)	O
,	O
Fred	O
Canter	O
,	O
Jerry	O
Brenner	O
,	O
Stettner	O
,	O
Bill	O
Burns	O
,	O
Mary	O
Anne	O
Cacciola	O
,	O
and	O
Bill	O
Munson	O
–	O
but	O
the	O
work	O
of	O
primarily	O
Canter	O
and	O
Brenner	O
.	O
</s>
<s>
V7M	O
contained	O
many	O
fixes	O
to	O
the	O
kernel	B-Operating_System
including	O
support	O
for	O
separate	O
instruction	O
and	O
data	O
spaces	O
,	O
significant	O
work	O
for	O
hardware	O
error	O
recovery	O
,	O
and	O
many	O
device	O
drivers	O
.	O
</s>
<s>
V7M	O
was	O
well	O
respected	O
in	O
the	O
Unix	B-Application
community	O
.	O
</s>
<s>
UEG	O
evolved	O
into	O
the	O
group	O
that	O
later	O
developed	O
Ultrix	B-Operating_System
.	O
</s>
<s>
The	O
first	O
native	O
VAX	B-Device
UNIX	B-Application
product	O
from	O
DEC	O
was	O
Ultrix-32	B-Operating_System
,	O
based	O
on	O
4.2BSD	O
with	O
some	O
non-kernel	O
features	O
from	O
System	B-Operating_System
V	I-Operating_System
,	O
and	O
was	O
released	O
in	O
June	O
1984	O
.	O
</s>
<s>
Ultrix-32	B-Operating_System
was	O
primarily	O
the	O
brainchild	O
of	O
Armando	O
Stettner	O
.	O
</s>
<s>
It	O
provided	O
a	O
Berkley-based	O
native	O
VAX	B-Device
Unix	B-Application
on	O
a	O
broad	O
array	O
of	O
hardware	O
configurations	O
without	O
the	O
need	O
to	O
access	O
kernel	B-Operating_System
sources	O
.	O
</s>
<s>
A	O
further	O
goal	O
was	O
to	O
enable	O
better	O
support	O
by	O
DEC	O
's	O
field	O
software	O
and	O
systems	O
support	O
engineers	O
through	O
better	O
hardware	O
support	O
,	O
system	O
messages	B-Architecture
,	O
and	O
documentation	O
.	O
</s>
<s>
Later	O
,	O
Ultrix-32	B-Operating_System
incorporated	O
support	O
for	O
DECnet	B-Protocol
and	O
other	O
proprietary	B-Application
DEC	O
protocols	O
such	O
as	O
LAT	B-General_Concept
.	O
</s>
<s>
It	O
did	O
not	O
support	O
VAXclustering	B-Operating_System
.	O
</s>
<s>
DEC	O
provided	O
Ultrix	B-Operating_System
on	O
three	O
platforms	O
:	O
PDP-11	B-Device
minicomputers	O
(	O
where	O
Ultrix	B-Operating_System
was	O
one	O
of	O
many	O
available	O
operating	O
systems	O
from	O
DEC	O
)	O
,	O
VAX-based	O
computers	O
(	O
where	O
Ultrix	B-Operating_System
was	O
one	O
of	O
two	O
primary	O
OS	O
choices	O
)	O
and	O
the	O
Ultrix-only	O
DECstation	B-Device
workstations	O
and	O
DECsystem	B-Device
servers	O
.	O
</s>
<s>
Note	O
that	O
the	O
DECstation	B-Device
and	O
the	O
later	O
DECsystem	B-Device
products	O
(	O
as	O
opposed	O
to	O
DEC	O
's	O
original	O
DECsystem	B-Device
line	O
)	O
used	O
MIPS	B-Device
processors	O
and	O
predate	O
the	O
much	O
later	O
Alpha-based	O
systems	O
.	O
</s>
<s>
The	O
V7m	O
product	O
was	O
later	O
renamed	O
to	O
Ultrix-11	B-Operating_System
to	O
establish	O
the	O
family	O
with	O
Ultrix-32	B-Operating_System
,	O
but	O
as	O
the	O
PDP-11	B-Device
faded	O
from	O
view	O
Ultrix-32	B-Operating_System
became	O
known	O
simply	O
as	O
Ultrix	B-Operating_System
.	O
</s>
<s>
When	O
the	O
MIPS	B-Device
versions	O
of	O
Ultrix	B-Operating_System
was	O
released	O
,	O
the	O
VAX	B-Device
and	O
MIPS	B-Device
versions	O
were	O
referred	O
to	O
as	O
VAX/ULTRIX	O
and	O
RISC/ULTRIX	O
respectively	O
.	O
</s>
<s>
Much	O
engineering	O
emphasis	O
was	O
placed	O
on	O
supportability	O
and	O
reliable	O
operations	O
including	O
continued	O
work	O
on	O
CPU	B-General_Concept
and	O
device	O
driver	O
support	O
(	O
which	O
was	O
,	O
for	O
the	O
most	O
part	O
,	O
also	O
sent	O
to	O
UC	O
Berkeley	O
)	O
,	O
hardware	O
failure	O
support	O
and	O
recovery	O
with	O
enhancement	O
to	O
error	O
message	O
text	O
,	O
documentation	O
,	O
and	O
general	O
work	O
at	O
both	O
the	O
kernel	B-Operating_System
and	O
systems	O
program	O
levels	O
.	O
</s>
<s>
Later	O
Ultrix-32	B-Operating_System
incorporated	O
some	O
features	O
from	O
4.3BSD	O
and	O
optionally	O
included	O
DECnet	B-Protocol
and	O
SNA	B-Architecture
in	O
addition	O
to	O
the	O
standard	O
TCP/IP	B-Protocol
,	O
and	O
both	O
the	O
SMTP	B-Protocol
and	O
DEC	O
's	O
Mail-11	O
protocols	O
.	O
</s>
<s>
Notably	O
,	O
Ultrix	B-Operating_System
implemented	O
the	O
inter-process	B-Operating_System
communication	I-Operating_System
(	O
IPC	O
)	O
facilities	O
found	O
in	O
System	B-Operating_System
V	I-Operating_System
(	O
named	B-Operating_System
pipes	I-Operating_System
,	O
messages	B-Architecture
,	O
semaphores	B-Operating_System
,	O
and	O
shared	B-Operating_System
memory	I-Operating_System
)	O
.	O
</s>
<s>
While	O
the	O
converged	O
Unix	B-Application
from	O
the	O
Sun	O
and	O
AT&T	O
alliance	O
(	O
that	O
spawned	O
the	O
Open	B-Application
Software	I-Application
Foundation	I-Application
or	O
OSF	O
)	O
,	O
released	O
late	O
1986	O
,	O
put	O
BSD	B-Operating_System
features	O
into	O
System	B-Operating_System
V	I-Operating_System
,	O
DEC	O
,	O
as	O
described	O
in	O
Stettner	O
's	O
original	O
Ultrix	B-Operating_System
plans	O
,	O
took	O
the	O
best	O
from	O
System	B-Operating_System
V	I-Operating_System
and	O
added	O
it	O
to	O
a	O
BSD	B-Operating_System
base	O
.	O
</s>
<s>
Originally	O
,	O
on	O
the	O
VAX	B-Device
workstations	O
,	O
Ultrix-32	B-Operating_System
had	O
a	O
desktop	O
environment	O
called	O
UWS	O
,	O
Ultrix	B-Operating_System
Worksystem	O
Software	O
,	O
which	O
was	O
based	O
on	O
X10	B-Operating_System
and	O
the	O
Ultrix	B-Device
Window	I-Device
Manager	I-Device
.	O
</s>
<s>
Later	O
,	O
the	O
widespread	O
version	O
11	O
of	O
the	O
X	B-Operating_System
Window	I-Operating_System
System	I-Operating_System
(	O
X11	B-Operating_System
)	O
was	O
added	O
,	O
using	O
a	O
window	O
manager	O
and	O
widget	B-Library
toolkit	I-Library
named	O
XUI	B-Application
(	O
X	B-Operating_System
User	O
Interface	O
)	O
,	O
which	O
was	O
also	O
used	O
on	O
VMS	B-Operating_System
releases	O
of	O
the	O
time	O
.	O
</s>
<s>
Eventually	O
Ultrix	B-Operating_System
also	O
provided	O
the	O
Motif	B-Application
toolkit	I-Application
and	O
Motif	B-Device
Window	I-Device
Manager	I-Device
.	O
</s>
<s>
Ultrix	B-Operating_System
ran	O
on	O
multiprocessor	B-Operating_System
systems	O
from	O
both	O
the	O
VAX	B-Device
and	O
DECsystem	B-Device
families	O
.	O
</s>
<s>
Ultrix-32	B-Operating_System
supported	O
SCSI	B-Architecture
disks	O
and	O
tapes	O
and	O
also	O
proprietary	B-Application
Digital	B-Architecture
Storage	I-Architecture
Systems	I-Architecture
Interconnect	I-Architecture
and	O
CI	O
peripherals	O
employing	O
DEC	O
's	O
Mass	B-Device
Storage	I-Device
Control	I-Device
Protocol	I-Device
,	O
although	O
lacking	O
the	O
OpenVMS	B-Operating_System
distributed	O
lock	O
manager	O
it	O
did	O
not	O
support	O
concurrent	O
access	O
from	O
multiple	O
Ultrix	B-Operating_System
systems	O
.	O
</s>
<s>
DEC	O
also	O
released	O
a	O
combination	O
hardware	O
and	O
software	O
product	O
named	O
Prestoserv	O
which	O
accelerated	O
NFS	O
file	O
serving	O
to	O
allow	O
better	O
performance	O
for	O
diskless	O
workstations	O
to	O
communicate	O
to	O
a	O
file	O
serving	O
Ultrix	B-Operating_System
host	O
.	O
</s>
<s>
The	O
kernel	B-Operating_System
supported	O
symmetric	B-Operating_System
multiprocessing	I-Operating_System
while	O
not	O
being	O
fully	O
multithreaded	B-Operating_System
based	O
upon	O
pre-Ultrix	O
work	O
by	O
Armando	O
Stettner	O
and	O
earlier	O
work	O
by	O
George	O
H	O
.	O
Goble	O
at	O
Purdue	O
University	O
.	O
</s>
<s>
the	O
processing	O
of	O
interrupts	B-Application
)	O
.	O
</s>
<s>
SunOS	B-Operating_System
)	O
.	O
</s>
<s>
Also	O
,	O
Ultrix	B-Operating_System
was	O
slow	O
to	O
support	O
many	O
then	O
new	O
or	O
emerging	O
Unix	B-Application
system	I-Application
capabilities	O
found	O
on	O
competing	O
Unix	B-Application
systems	I-Application
(	O
e.g.	O
</s>
<s>
The	O
absence	O
of	O
memory-mapped	O
file	O
support	O
was	O
regarded	O
as	O
a	O
particular	O
deficiency	O
with	O
Ultrix	B-Operating_System
in	O
comparison	O
to	O
its	O
competitors	O
in	O
the	O
early	O
1990s	O
.	O
</s>
<s>
As	O
part	O
of	O
its	O
commitment	O
to	O
the	O
OSF	O
,	O
Armando	O
Stettner	O
went	O
to	O
DEC	O
's	O
Cambridge	O
Research	O
Labs	O
to	O
work	O
on	O
the	O
port	O
of	O
OSF/1	B-Operating_System
to	O
DEC	O
's	O
RISC-based	O
DECstation	B-Device
3100	I-Device
workstation	O
.	O
</s>
<s>
This	O
was	O
released	O
in	O
1991	O
with	O
a	O
Mach-based	O
kernel	B-Operating_System
for	O
the	O
MIPS	B-Device
architecture	I-Device
.	O
</s>
<s>
A	O
port	O
of	O
Ultrix	B-Operating_System
to	O
Alpha	B-Device
was	O
carried	O
out	O
during	O
the	O
initial	O
development	O
of	O
the	O
Alpha	B-Device
architecture	O
,	O
but	O
was	O
never	O
released	O
as	O
a	O
product	O
.	O
</s>
<s>
Later	O
,	O
DEC	O
replaced	O
Ultrix	B-Operating_System
with	O
OSF/1	B-Operating_System
on	O
Alpha	B-Device
,	O
ending	O
Unix	B-Application
development	O
on	O
the	O
MIPS	B-Device
and	O
VAX	B-Device
platforms	O
.	O
</s>
<s>
The	O
last	O
major	O
release	O
of	O
Ultrix	B-Operating_System
was	O
version	O
4.5	O
in	O
1995	O
,	O
which	O
supported	O
all	O
previously	O
supported	O
DECstations	B-Device
and	O
VAXen	B-Device
.	O
</s>
<s>
There	O
were	O
some	O
subsequent	O
Y2K	B-Error_Name
patches	O
.	O
</s>
<s>
WordMARC	B-Protocol
,	O
a	O
scientifically-oriented	O
word	O
processor	O
,	O
was	O
among	O
the	O
application	O
packages	O
available	O
for	O
Ultrix	B-Operating_System
.	O
</s>
<s>
The	O
following	O
shells	O
were	O
provided	O
with	O
Ultrix	B-Operating_System
:	O
</s>
