<s>
Tru64	B-Operating_System
UNIX	I-Operating_System
is	O
a	O
discontinued	O
64-bit	B-Device
UNIX	B-Application
operating	I-Application
system	I-Application
for	O
the	O
Alpha	B-Device
instruction	B-General_Concept
set	I-General_Concept
architecture	I-General_Concept
(	O
ISA	O
)	O
,	O
currently	O
owned	O
by	O
Hewlett-Packard	O
(	O
HP	O
)	O
.	O
</s>
<s>
Previously	O
,	O
Tru64	B-Operating_System
UNIX	I-Operating_System
was	O
a	O
product	O
of	O
Compaq	O
,	O
and	O
before	O
that	O
,	O
Digital	O
Equipment	O
Corporation	O
(	O
DEC	O
)	O
,	O
where	O
it	O
was	O
known	O
as	O
Digital	B-Operating_System
UNIX	I-Operating_System
(	O
originally	O
DEC	B-Operating_System
OSF/1	I-Operating_System
AXP	I-Operating_System
)	O
.	O
</s>
<s>
As	O
its	O
original	O
name	O
suggests	O
,	O
Tru64	B-Operating_System
UNIX	I-Operating_System
is	O
based	O
on	O
the	O
OSF/1	B-Operating_System
operating	B-General_Concept
system	I-General_Concept
.	O
</s>
<s>
DEC	O
's	O
previous	O
UNIX	B-Application
product	O
was	O
known	O
as	O
Ultrix	B-Operating_System
and	O
was	O
based	O
on	O
BSD	B-Operating_System
.	O
</s>
<s>
It	O
is	O
unusual	O
among	O
commercial	O
UNIX	B-Application
implementations	O
,	O
as	O
it	O
is	O
built	O
on	O
top	O
of	O
the	O
Mach	B-Operating_System
kernel	I-Operating_System
developed	O
at	O
Carnegie	O
Mellon	O
University	O
.	O
</s>
<s>
(	O
Other	O
UNIX	B-Application
and	O
UNIX-like	B-Operating_System
implementations	O
built	O
on	O
top	O
of	O
the	O
Mach	B-Operating_System
kernel	I-Operating_System
are	O
GNU	B-Application
Hurd	I-Application
,	O
NeXTSTEP	B-Application
,	O
MkLinux	B-Application
,	O
macOS	B-Application
and	O
Apple	B-Operating_System
iOS	I-Operating_System
.	O
)	O
</s>
<s>
Tru64	B-Operating_System
UNIX	I-Operating_System
required	O
the	O
SRM	B-General_Concept
boot	O
firmware	B-Application
found	O
on	O
Alpha-based	O
computer	O
systems	O
.	O
</s>
<s>
In	O
1988	O
,	O
Digital	O
Equipment	O
Corporation	O
(	O
DEC	O
)	O
joined	O
with	O
IBM	O
,	O
Hewlett-Packard	O
,	O
and	O
others	O
to	O
form	O
the	O
Open	B-Application
Software	I-Application
Foundation	I-Application
(	O
OSF	O
)	O
.	O
</s>
<s>
A	O
primary	O
aim	O
was	O
to	O
develop	O
a	O
version	O
of	O
Unix	B-Application
,	O
named	O
OSF/1	B-Operating_System
,	O
to	O
compete	O
with	O
System	B-Operating_System
V	I-Operating_System
Release	O
4	O
from	O
AT&T	O
Corporation	O
and	O
Sun	O
Microsystems	O
.	O
</s>
<s>
After	O
DEC	O
's	O
first	O
release	O
(	O
OSF/1	B-Operating_System
Release	O
1.0	O
)	O
in	O
January	O
1992	O
for	O
their	O
line	O
of	O
MIPS-based	O
DECstation	B-Device
workstations	O
,	O
DEC	O
ported	O
OSF/1	B-Operating_System
to	O
their	O
new	O
Alpha	B-Device
AXP	I-Device
platform	O
(	O
as	O
DEC	B-Operating_System
OSF/1	I-Operating_System
AXP	I-Operating_System
)	O
,	O
and	O
this	O
was	O
the	O
first	O
version	O
(	O
Release	O
1.2	O
)	O
of	O
what	O
is	O
most	O
commonly	O
referred	O
to	O
as	O
OSF/1	B-Operating_System
.	O
</s>
<s>
DEC	B-Operating_System
OSF/1	I-Operating_System
AXP	I-Operating_System
Release	O
1.2	O
was	O
shipped	O
in	O
March	O
1993	O
.	O
</s>
<s>
OSF/1	B-Operating_System
AXP	I-Operating_System
was	O
a	O
full	O
64-bit	B-Device
operating	B-General_Concept
system	I-General_Concept
and	O
the	O
native	O
UNIX	B-Application
implementation	O
for	O
the	O
Alpha	B-Device
architecture	O
.	O
</s>
<s>
After	O
OSF/1	B-Operating_System
AXP	I-Operating_System
V2.0	O
onwards	O
,	O
UNIX	B-Operating_System
System	I-Operating_System
V	I-Operating_System
compatibility	O
was	O
also	O
integrated	O
into	O
the	O
system	O
.	O
</s>
<s>
In	O
1995	O
,	O
starting	O
with	O
release	O
3.2	O
,	O
DEC	O
renamed	O
OSF/1	B-Operating_System
AXP	I-Operating_System
to	O
Digital	B-Operating_System
UNIX	I-Operating_System
to	O
reflect	O
its	O
conformance	O
with	O
the	O
X/Open	O
Single	O
UNIX	B-Application
Specification	O
.	O
</s>
<s>
After	O
Compaq	O
's	O
purchase	O
of	O
DEC	O
in	O
early	O
1998	O
,	O
with	O
the	O
release	O
of	O
version	O
4.0F	O
,	O
Digital	B-Operating_System
UNIX	I-Operating_System
was	O
renamed	O
to	O
Tru64	B-Operating_System
UNIX	I-Operating_System
to	O
emphasise	O
its	O
64-bit-clean	O
nature	O
and	O
de-emphasise	O
the	O
Digital	O
brand	O
.	O
</s>
<s>
In	O
April	O
1999	O
,	O
Compaq	O
announced	O
that	O
Tru64	B-Operating_System
UNIX	I-Operating_System
5.0	O
successfully	O
ran	O
on	O
Intel	O
's	O
IA-64	B-General_Concept
simulator	O
.	O
</s>
<s>
A	O
Chinese	O
version	O
of	O
Tru64	B-Operating_System
UNIX	I-Operating_System
named	O
COSIX	B-Operating_System
was	O
jointly	O
developed	O
by	O
Compaq	O
and	O
China	O
National	O
Computer	O
Software	O
&	O
Technology	O
Service	O
Corporation	O
(	O
CS&S	O
)	O
.	O
</s>
<s>
From	O
release	O
V5.0	O
Tru64	B-Operating_System
UNIX	I-Operating_System
offered	O
a	O
clustering	B-Architecture
facility	O
named	O
TruCluster	B-General_Concept
Server	O
.	O
</s>
<s>
TruCluster	B-General_Concept
utilised	O
a	O
cluster-wide	O
filesystem	O
visible	O
to	O
each	O
cluster	O
member	O
,	O
plus	O
member	O
specific	O
storage	O
and	O
an	O
optional	O
quorum	O
disk	O
.	O
</s>
<s>
Member	O
specific	O
files	O
paths	O
were	O
enhanced	O
symbolic	B-Application
links	I-Application
incorporating	O
the	O
member	O
id	O
of	O
the	O
owning	O
member	O
.	O
</s>
<s>
Each	O
member	O
had	O
one	O
or	O
zero	O
votes	O
,	O
which	O
,	O
combined	O
with	O
a	O
possible	O
quorum	O
disk	O
,	O
implemented	O
a	O
cluster	O
formation	O
algorithm	O
similar	O
to	O
that	O
found	O
in	O
OpenVMS	B-Operating_System
.	O
</s>
<s>
With	O
their	O
purchase	O
of	O
Compaq	O
in	O
2002	O
,	O
HP	O
announced	O
their	O
intention	O
to	O
migrate	O
many	O
of	O
Tru64	B-Operating_System
UNIX	I-Operating_System
's	O
more	O
innovative	O
features	O
(	O
including	O
its	O
AdvFS	B-Application
,	O
TruCluster	B-General_Concept
,	O
and	O
LSM	O
)	O
to	O
HP-UX	B-Application
.	O
</s>
<s>
In	O
December	O
2004	O
,	O
HP	O
announced	O
a	O
change	O
of	O
plan	O
:	O
they	O
would	O
instead	O
use	O
the	O
Veritas	B-Application
File	I-Application
System	I-Application
and	O
abandon	O
the	O
Tru64	B-Operating_System
advanced	O
features	O
.	O
</s>
<s>
In	O
the	O
process	O
,	O
many	O
of	O
the	O
remaining	O
Tru64	B-Operating_System
developers	O
were	O
laid	O
off	O
.	O
</s>
<s>
In	O
October	O
2010	O
,	O
HP	O
stated	O
that	O
they	O
would	O
continue	O
to	O
support	O
Tru64	B-Operating_System
UNIX	I-Operating_System
until	O
31	O
December	O
2012	O
.	O
</s>
<s>
In	O
2008	O
,	O
HP	O
contributed	O
the	O
AdvFS	B-Application
filesystem	O
to	O
the	O
open-source	O
community	O
.	O
</s>
<s>
These	O
versions	O
were	O
released	O
for	O
Alpha	B-Device
AXP	I-Device
platforms	O
.	O
</s>
<s>
Version	O
Approx	O
Date	O
Notes	O
DEC	B-Operating_System
OSF/1	I-Operating_System
1.2	O
March	O
1993	O
DEC	B-Operating_System
OSF/1	I-Operating_System
1.2A	O
April	O
1993	O
Hardware	O
only	O
release	O
DEC	B-Operating_System
OSF/1	I-Operating_System
1.3	O
July	O
1993	O
DEC	B-Operating_System
OSF/1	I-Operating_System
1.3A	O
September	O
1993	O
DEC	B-Operating_System
OSF/1	I-Operating_System
1.3B	O
November	O
1993	O
Hardware	O
only	O
release	O
DEC	B-Operating_System
OSF/1	I-Operating_System
2.0	O
March	O
1994	O
DEC	B-Operating_System
OSF/1	I-Operating_System
2.0A	O
April	O
1994	O
Logical	O
Storage	O
Manager	O
(	O
LSM	O
)	O
v1	O
;	O
AdvFS	B-Application
v1	O
;	O
ASE	O
v1	O
introduced	O
DEC	B-Operating_System
OSF/1	I-Operating_System
2.0B	O
May	O
1994	O
Hardware	O
only	O
release	O
DEC	B-Operating_System
OSF/1	I-Operating_System
2.1	O
July	O
1994	O
DEC	B-Operating_System
OSF/1	I-Operating_System
3.0	O
August	O
1994	O
SMP	O
support	O
DEC	B-Operating_System
OSF/1	I-Operating_System
3.0A	O
September	O
1994	O
ASE	O
v1.1	O
;	O
System	B-Operating_System
V	I-Operating_System
Environment	O
DEC	B-Operating_System
OSF/1	I-Operating_System
3.0B	O
September	O
1994	O
Hardware	O
only	O
release	O
Digital	B-Operating_System
UNIX	I-Operating_System
3.2	O
February	O
1995	O
Digital	B-Operating_System
UNIX	I-Operating_System
3.2A	O
March	O
1995	O
ASE	O
v1.2	O
Digital	B-Operating_System
UNIX	I-Operating_System
3.2B	O
May	O
1995	O
Hardware	O
only	O
release	O
Digital	B-Operating_System
UNIX	I-Operating_System
3.2C	O
July	O
1995	O
Digital	B-Operating_System
UNIX	I-Operating_System
3.2D-1	O
January	O
1996	O
ASE	O
v1.3	O
Digital	B-Operating_System
UNIX	I-Operating_System
3.2D-2	O
January	O
1996	O
Hardware	O
only	O
release	O
Digital	B-Operating_System
UNIX	I-Operating_System
3.2E	O
March	O
1996	O
TruCluster	B-General_Concept
v1.0	O
Digital	B-Operating_System
UNIX	I-Operating_System
4.0	O
March	O
1996	O
CDE	O
made	O
default	O
desktop	O
Digital	B-Operating_System
UNIX	I-Operating_System
3.2F	O
June	O
1996	O
Digital	B-Operating_System
UNIX	I-Operating_System
3.2G	O
August	O
1996	O
Digital	B-Operating_System
UNIX	I-Operating_System
4.0A	O
September	O
1996	O
ASE	O
v1.4	O
Digital	B-Operating_System
UNIX	I-Operating_System
4.0B	O
December	O
1996	O
X/Open	O
-compliant	O
Curses	O
Digital	B-Operating_System
UNIX	I-Operating_System
4.0C	O
April	O
1997	O
Digital	B-Operating_System
UNIX	I-Operating_System
4.0D	O
December	O
1997	O
Y2K	O
readiness	O
;	O
extended	O
UIDs/GIDs	O
;	O
class	O
scheduler	O
;	O
JDK	O
1.1.4	O
;	O
Netscape	O
3.04	O
Digital	B-Operating_System
UNIX	I-Operating_System
4.0E	O
November	O
1998	O
ASE	O
v1.5	O
;	O
USB	O
support	O
;	O
AdvFS	B-Application
atomic	O
write	O
data	O
logging	O
;	O
Sendmail	O
8.8.8	O
;	O
ODBC/JDBC	O
;	O
Netscape	O
4.05	O
Tru64	B-Operating_System
UNIX	I-Operating_System
4.0F	O
April	O
1999	O
USB	O
keyboard/mouse	O
support	O
;	O
limited	O
DVD	O
support	O
;	O
Netscape	O
4.5	O
;	O
COM	O
for	O
Tru64	B-Operating_System
UNIX	I-Operating_System
Tru64	B-Operating_System
UNIX	I-Operating_System
5.0	O
July	O
1999	O
Improved	O
performance/scalability	O
;	O
Hot-swap	O
;	O
Sendmail	O
8.8.8	O
;	O
OpenMP	O
;	O
Netscape	O
4.51	O
;	O
X11R6.3	O
Tru64	B-Operating_System
UNIX	I-Operating_System
5.0A	O
April	O
2000	O
UFS	O
Delayed	O
metadata	O
option	O
;	O
Sendmail	O
8.9.3	O
;	O
Netscape	O
4.7	O
;	O
ISO	O
9660	O
install	O
disc	O
Tru64	B-Operating_System
UNIX	I-Operating_System
4.0G	O
May	O
2000	O
Maximum	O
256	O
X	O
clients	O
(	O
formerly	O
128	O
)	O
;	O
Netscape	O
4.7	O
Tru64	B-Operating_System
UNIX	I-Operating_System
5.1	O
September	O
2000	O
Extended	O
System	B-Operating_System
V	I-Operating_System
functionality	O
;	O
Tcl/Tk	O
8.2	O
;	O
IPv6	O
Tru64	B-Operating_System
UNIX	I-Operating_System
5.1A	O
September	O
2001	O
Online	O
CPU	O
addition/removal	O
;	O
UNIX	B-Application
98	O
Conformance	O
;	O
X11R6.5	O
;	O
Netscape	O
4.76	O
Tru64	B-Operating_System
UNIX	I-Operating_System
5.1B	O
September	O
2002	O
Big	O
Pages	O
;	O
IPv6	O
Enhancements	O
;	O
Netscape	O
6	O
;	O
Unicode	O
3.1	O
Tru64	B-Operating_System
UNIX	I-Operating_System
5.1B-1	O
November	O
2003	O
Name	O
Service	O
Switch	O
(	O
NSS	O
)	O
;	O
Mozilla	O
1.4	O
Tru64	B-Operating_System
UNIX	I-Operating_System
5.1B-2	O
August	O
2004	O
Unified	O
Buffer	O
Cache	O
Scaling	O
;	O
Perl	O
5.8.4	O
;	O
Mozilla	O
1.6	O
Tru64	B-Operating_System
UNIX	I-Operating_System
5.1B-3	O
June	O
2005	O
AdvFS	B-Application
robustness	O
;	O
Accounting	O
refinements	O
;	O
LSM	O
enhancements	O
;	O
Mozilla	O
1.7.5	O
Tru64	B-Operating_System
UNIX	I-Operating_System
5.1B-4	O
December	O
2006	O
POSIX	O
conformance	O
;	O
Rebranding	O
(	O
COMPAQ	O
to	O
HP	O
)	O
;	O
2007	O
U.S.	O
DST	O
changes	O
;	O
BIND	O
9.2.5	O
Tru64	B-Operating_System
UNIX	I-Operating_System
5.1B-5	O
March	O
2009	O
Standards	O
conformance	O
;	O
Support	O
for	O
latest	O
DST	O
changes	O
;	O
BIND	O
9.2.8	O
Tru64	B-Operating_System
UNIX	I-Operating_System
5.1B-6	O
October	O
2010	O
Defect	O
fixes	O
only	O
.	O
</s>
