OS/2 is a series of computer operating systems, initially created by
IBM under the leadership of
IBM software designer Ed
Iacobucci. As a result of a feud between the two companies over how
OS/2 relative to Microsoft's new
Windows 3.1 operating
environment, the two companies severed the relationship in 1992 and
OS/2 development fell to
IBM exclusively. The name stands for
"Operating System/2", because it was introduced as part of the same
generation change release as IBM's "Personal System/2 (PS/2)" line of
second-generation personal computers. The first version of
released in December 1987 and newer versions were released until
OS/2 was intended as a protected mode successor of PC DOS.
Notably, basic system calls were modelled after
MS-DOS calls; their
names even started with "Dos" and it was possible to create "Family
Mode" applications: text mode applications that could work on both
systems. Because of this heritage,
OS/2 shares similarities with
Unix, Xenix, and
Windows NT in many ways.
IBM discontinued its support for
OS/2 on 31 December 2006. Since
then, it has been updated, maintained and marketed under the name
eComStation. In 2015 it was announced that a new OEM distribution
OS/2 would be released that was to be called ArcaOS.
available for purchase.
1 Development history
1.1 1985–1989: Joint development
1.2 1990: Breakup
1.3.2 Windows 3.x compatibility
1.4 1994–1996: The "Warp" years
1.5 Workplace OS
1.7 2001: Fading out
1.8 Security niche
1.9 Petitions for open source
2 Summary of releases
4 Historical uses
IBM products utilizing OS/2
7 See also
9 Further reading
10 External links
1985–1989: Joint development
The development of
OS/2 began when
Microsoft signed the "Joint
Development Agreement" in August 1985. It was code-named
"CP/DOS" and it took two years for the first product to be delivered.
OS/2 1.0 was announced in April 1987 and released in December. The
original release is textmode-only, and a GUI was introduced with OS/2
1.1 about a year later.
OS/2 features an API for controlling the video
display (VIO) and handling keyboard and mouse events so that
programmers writing for protected-mode need not call the
access hardware directly. In addition, development tools include a
subset of the video and keyboard APIs as linkable libraries so that
family mode programs are able to run under MS-DOS. A task-switcher
named Program Selector is available through the Ctrl-Esc hotkey
combination, allowing the user to select among multitasked text-mode
sessions (or screen groups; each can run multiple programs).
Communications and database-oriented extensions were delivered in
1988, as part of
OS/2 1.0 Extended Edition: SNA, X.25/APPC/LU 6.2, LAN
Manager, Query Manager, SQL.
The promised user interface, Presentation Manager, was introduced with
OS/2 1.1 in October 1988. It had a similar user interface to
Windows 2.1, which was released in May of that year. (The interface
was replaced in versions 1.2 and 1.3 by a look closer in appearance to
The Extended Edition of 1.1, sold only through
IBM sales channels,
introduced distributed database support to
IBM database systems and
SNA communications support to
IBM mainframe networks.
In 1989, Version 1.2 introduced Installable Filesystems and notably
the HPFS filesystem. HPFS provided a number of improvements over the
older FAT file system, including long filenames and a form of
alternate data streams called Extended Attributes. In addition,
extended attributes were also added to the FAT file system.
Installation Disk A of
OS/2 1.3 (3½-inch floppy disk)
The Extended Edition of 1.2 introduced TCP/IP and
OS/2 and Windows-related books of the late 1980s acknowledged the
existence of both systems and promoted
OS/2 as the system for the
The collaboration between
Microsoft unravelled in 1990,
between the releases of
Windows 3.0 and
OS/2 1.3. During this time,
Windows 3.0 became a tremendous success, selling millions of copies in
its first year. Much of its success was because
Windows 3.0 (along
with MS-DOS) was bundled with most new computers. OS/2, on the
other hand, was available only as an additional stand-alone software
package. In addition,
OS/2 lacked device drivers for many common
devices such as printers, particularly non-
IBM hardware. Windows,
on the other hand, supported a much larger variety of hardware. The
increasing popularity of Windows prompted
Microsoft to shift its
development focus from cooperating on
IBM to building its
own business based on Windows.
Several technical and practical reasons contributed to this breakup.
The two companies had significant differences in culture and vision.
Microsoft favored the open hardware system approach that contributed
to its success on the PC;
IBM sought to use
OS/2 to drive sales of its
own hardware, including systems that could not support the features
Microsoft programmers also became frustrated with
IBM's bureaucracy and its use of lines of code to measure programmer
IBM developers complained about the terseness and
lack of comments in Microsoft's code, while
complained that IBM's code was bloated.
The two products have significant differences in API.
Windows 2.0 was near completion, and the Windows API
already defined. However,
IBM requested that this API be significantly
changed for OS/2. Therefore, issues surrounding application
compatibility appeared immediately.
OS/2 designers hoped for source
code conversion tools, allowing complete migration of Windows
application source code to
OS/2 at some point. However,
OS/2 1.x did
not gain enough momentum to allow vendors to avoid developing for both
OS/2 and Windows in parallel.
OS/2 1.x targets the
Intel 80286 processor and
IBM insisted on supporting the 80286 processor, with its
16-bit segmented memory mode, because of commitments made to customers
who had purchased many 80286-based PS/2s as a result of IBM's promises
surrounding OS/2. Until release 2.0 in April 1992,
OS/2 ran in
16-bit protected mode and therefore could not benefit from the Intel
80386's much simpler
32-bit flat memory model and virtual 8086 mode
features. This was especially painful in providing support for DOS
applications. While, in 1988, Windows/386 2.1 could run several
DOS applications, including expanded memory
OS/2 1.3, released in 1991, was still limited to one
640 kB "
Given these issues,
Microsoft started to work in parallel on a version
of Windows which was more future-oriented and more portable. The
hiring of Dave Cutler, former VMS architect, in 1988 created an
immediate competition with the
OS/2 team, as Cutler did not think much
OS/2 technology and wanted to build on his work at Digital
rather than creating a "
DOS plus". His "NT OS/2" was a completely new
OS/2 2.0 upgrade box
IBM grew concerned about the delays in development of
Initially, the companies agreed that
IBM would take over maintenance
OS/2 1.0 and development of
OS/2 2.0, while
continue development of
OS/2 3.0. In the end,
Microsoft decided to
OS/2 3.0 as Windows NT, leaving all future
to IBM. From a business perspective, it was logical to concentrate on
a consumer line of operating systems based on
DOS and Windows, and to
prepare a new high-end system in such a way as to keep good
compatibility with existing Windows applications. While waiting for
this new high-end system to develop,
Microsoft would still receive
licensing money from
OS/2 sales. Windows NT's
can be seen in its initial support for the HPFS filesystem, text mode
OS/2 1.x applications, and
LAN Manager network support. Some
early NT materials even included
OS/2 copyright notices embedded in
the software. One example of NT
OS/2 1.x support is
in the WIN2K resource kit.
Windows NT could also support
Presentation Manager and AVIO applications with the addition of the
Windows NT Add-On Subsystem for Presentation Manager.
OS/2 2.0 was released in April 1992. It provided a
32-bit API for
native programs, though the OS itself still contained some 16-bit code
and drivers. It also included a new OOUI (object-oriented user
interface) called the Workplace Shell. This was a fully
object-oriented interface that was a significant departure from the
previous GUI. Rather than merely providing an environment for program
windows (such as the Program Manager), the
Workplace Shell provided an
environment in which a user could manage programs, files and devices
by manipulating objects on the screen. With the Workplace Shell,
everything in the system is an "object" to be manipulated.
OS/2 2.0 was touted by
IBM as "a better
DOS and a better
Windows than Windows". It managed this by including fully licensed
MS-DOS 5.0 which had been patched and improved upon. For the first
OS/2 was able to run more than one
DOS application at a time.
This was so effective that it allowed
OS/2 to run a modified copy of
Windows 3.0, itself a
DOS extender, including Windows 3.0
Because of the limitations of the
Intel 80286 processor,
could run only one
DOS program at a time, and did this in a way that
DOS program to have total control over the computer. A
DOS mode could crash the entire computer. In contrast, OS/2
2.0 could benefit from the virtual 8086 mode of the Intel 80386
processor to create a much safer virtual machine in which to run DOS
programs. This included an extensive set of configuration options to
optimize the performance and capabilities given to each
Any real mode operating system (such as 8086 Xenix) could also be made
to run using OS/2's virtual machine capabilities, subject to certain
direct hardware access limitations.
OS/2 could not run protected-mode DOS
programs using the older
VCPI interface, unlike the Standard mode of
Windows 3.1; it only supported programs written according to DPMI.
Microsoft discouraged the use of
VCPI under Windows 3.1, however, due
to performance degradation.)
Unlike Windows NT,
OS/2 also always gave
DOS programs the possibility
of masking real hardware interrupts, so any
DOS program could deadlock
the machine this way.
OS/2 could however use a hardware watchdog on
selected machines (notably
IBM machines) to break out of such a
deadlock. Later, release 3.0 leveraged the enhancements of newer Intel
486 and Intel Pentium processors—the Virtual
Interrupt Flag (VIF),
which was part of the
Virtual Mode Extensions (VME)—to solve this
Further information: VME (CONFIG.SYS directive)
Windows 3.x compatibility
Windows 3.0 (and later Windows 3.1) was achieved by
adapting Windows user-mode code components to run inside a virtual DOS
machine (VDM). Originally, a nearly complete version of Windows code
was included with
Windows 3.0 in
OS/2 2.0, and Windows
OS/2 2.1. Later,
IBM developed versions of
OS/2 that would use
whatever Windows version the user had installed previously, patching
it on the fly, and sparing the cost of an additional Windows
license. It could either run full-screen, using its own set of
video drivers, or "seamlessly," where Windows programs would appear
directly on the
OS/2 desktop. The process containing Windows was given
fairly extensive access to hardware, especially video, and the result
was that switching between a full-screen Win
OS/2 session and the
Workplace Shell could occasionally cause issues.
OS/2 only runs the user-mode system components of Windows, it
is not compatible with Windows device drivers (VxDs) and applications
Multiple Windows applications run by default in a single Windows
session - multitasking cooperatively and without memory protection -
just as they would under native Windows 3.x. However, to achieve true
isolation between Windows 3.x programs,
OS/2 also can run multiple
copies of Windows in parallel, with each copy residing in a separate
VDM. The user can then optionally place each program either in its own
Windows session - with preemptive multitasking and full memory
protection between sessions, though not within them - or allow some
applications to run together cooperatively in a shared Windows session
while isolating other applications in one or more separate Windows
sessions. At the cost of additional hardware resources, this approach
can protect each program in any given Windows session (and each
instance of Windows itself) from every other program running in any
separate Windows session (though not from other programs running in
the same Windows session).
Whether Windows applications are running in full-screen or windowed
mode, and in one Windows session or several, it is possible to use DDE
OS/2 and Windows applications, and OLE between Windows
1994–1996: The "Warp" years
OS/2 Warp 4 desktop after installation
Released in 1994,
OS/2 version 3.0 was labelled as
OS/2 Warp to
highlight the new performance benefits, and generally to freshen the
product image. "Warp" had originally been the internal
IBM name for
IBM claimed that it had used
Star Trek terms as internal
names for prior
OS/2 releases, and that this one seemed appropriate
for external use as well. At the launch of
OS/2 Warp in 1994, Patrick
Stewart was to be the Master of Ceremonies; however Kate Mulgrew
of the then-upcoming series Star Trek: Voyager was substituted at the
last minute.:p. 108
OS/2 Warp offers a host of benefits over
OS/2 2.1, notably broader
hardware support, greater multimedia capabilities, Internet-compatible
networking, and it includes a basic office application suite known as
IBM Works. It was released in two versions: the less expensive "Red
Spine" and the more expensive "Blue Spine" (named for the color of
their boxes). "Red Spine" was designed to support
applications by utilizing any existing installation of Windows on the
computer's hard drive. "Blue Spine" includes Windows support in its
own installation, and so can support Windows applications without a
Windows installation. As most computers were sold with Microsoft
Windows pre-installed and the price was less, "Red Spine" was the more
popular product.
OS/2 Warp Connect—which has full
LAN client support built-in—followed in mid-1995. Warp Connect was
OS/2 2.0, most performance-sensitive subsystems, including the
graphics (Gre) and multimedia (MMPM/2) systems, were updated to 32-bit
code in a fixpack, and included as part of
OS/2 2.1. Warp 3 brought
about a fully
32-bit windowing system, while Warp 4 introduced the
32-bit GRADD display driver model.
Mozilla 1.7.13 for
OS/2 Warp 4
Firefox 3.5.4 for
OS/2 Warp 4
In 1996, Warp 4 added Java and speech recognition software.
released server editions of Warp 3 and Warp 4 which bundled IBM's LAN
Server product directly into the operating system installation. A
personal version of Lotus Notes was also included, with a number of
template databases for contact management, brainstorming, and so
forth. The UK-distributed free demo
OS/2 Warp essentially
contained the entire OS and was easily, even accidentally,
cracked[clarification needed], meaning that even people who liked it
did not have to buy it. This was seen as a backdoor tactic to increase
the number of
OS/2 users, in the belief that this would increase sales
and demand for third-party applications, and thus strengthen OS/2's
desktop numbers. This suggestion was bolstered by the
fact that this demo version had replaced another which was not so
easily cracked, but which had been released with trial versions of
various applications. In 2000, the July edition of
Australian Personal Computer
Australian Personal Computer magazine bundled software CD-ROMs,
included a full version of Warp 4 that required no activation and was
essentially a free release.
Special versions of
OS/2 2.11 and Warp 4
also included symmetric multiprocessing (SMP) support.
OS/2 sales were largely concentrated in networked computing used by
corporate professionals; however, by the early 1990s, it was overtaken
Microsoft Windows NT. While
OS/2 was arguably technically superior
Microsoft Windows 95,
OS/2 failed to develop much penetration in
the consumer and stand-alone desktop PC segments; there were reports
that it could not be installed properly on IBM's own Aptiva series of
Microsoft made an offer in 1994 where
IBM would receive
the same terms as
Compaq (the largest PC manufacturer at the time) for
a license of Windows 95, if
IBM ended development of
IBM refused and instead went with an "
IBM First" strategy of promoting
OS/2 Warp and disparaging Windows, as
IBM aimed to drive sales of its
own software as well as hardware. By 1995,
Windows 95 negotiations
IBM and Microsoft, which were already difficult, stalled when
IBM purchased Lotus SmartSuite, which would have directly competed
Microsoft Office. As a result of the dispute,
IBM signed the
license agreement 15 minutes before Microsoft's
Windows 95 launch
event, which was later than their competitors and this badly hurt
IBM officials later conceded that
OS/2 would not
have been a viable operating system to keep them in the PC
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Main article: Workplace OS
IBM started development on an intended replacement for OS/2
called Workplace OS. This was an entirely new product, brand new code,
that borrowed only a few sections of code from both the existing OS/2
and AIX products. It used an entirely new microkernel code base,
intended (eventually) to host several of IBM's operating systems
(including OS/2) as microkernel "personalities". It also included
major new architectural features including a system registry, JFS,
support for UNIX graphics libraries, and a new driver model.
Workplace OS was developed solely for POWER platforms, and IBM
intended to market a full line of PowerPCs in an effort to take over
the market from Intel. A mission was formed to create prototypes of
these machines and they were disclosed to several Corporate customers,
all of whom raised issues with the idea of dropping Intel.
Advanced plans for the new code base would eventually include
replacement of the OS/400 operating system by Workplace OS, as well as
a microkernel product that would have been used in industries such as
telecommunications and set-top television receivers.
A partial pre-alpha version of
Workplace OS was demonstrated at Comdex
where a bemused
Bill Gates stopped by the booth. The second and last
time it was shown in public was at an
OS/2 user group in Phoenix AZ,
where the pre-alpha code refused to boot.
It was released in 1995. But with $990 million being spent per year on
development of this as well as Workplace OS, and no possible profit or
widespread adoption, the end of the entire
Workplace OS and OS/2
product line was near.
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A project was launched internally by
IBM to evaluate the looming
competitive situation with
Microsoft Windows 95. Primary concerns
included the major code quality issues in the existing
(resulting in over 20 service packs, each requiring more diskettes
than the original installation), and the ineffective and heavily
matrixed development organization in Boca Raton (where the consultants
reported that "basically, everybody reports to everybody") and Austin.
That study, tightly classified as "Registered Confidential" and
printed only in numbered copies, identified untenable weaknesses and
failures across the board in the Personal Systems Division as well as
IBM as a whole. This resulted in a decision being made at a
level above the Division to cut over 95% of the overall budget for the
entire product line, end all new development (including Workplace OS),
eliminate the Boca Raton development lab, end all sales and marketing
efforts of the product, and lay off over 1,300 development individuals
(as well as sales and support personnel). $990 million had been spent
in the last full year. Warp 4 became the last distributed version of
2001: Fading out
An ATM in
A small and dedicated community remained faithful to
OS/2 for many
years after its final mainstream release, but overall,
to catch on in the mass market and is little used outside certain
IBM traditionally had a stronghold. For example, many
bank installations, especially automated teller machines, run OS/2
with a customized user interface; French
SNCF national railways used
OS/2 1.x in thousands of ticket selling machines.
Telecom companies such as
OS/2 in some voicemail systems.
OS/2 was used for the host PC used to control the Satellite
Operations Support System equipment installed at
NPR member stations
from 1994 to 2007, and used to receive the network's programming via
IBM began indicating shortly after the release of Warp 4 that
OS/2 would eventually be withdrawn, the company did not end support
until December 31, 2006. Sales of
OS/2 stopped on December 23,
2005. The latest
IBM version is 4.52, which was released for both
desktop and server systems in December 2001. Serenity Systems has been
OS/2 since 2001, calling it eComStation. Version 1.2 was
released in 2004. After a series of preliminary "release candidates,"
version 2.0 GA (General Availability) was released on 15 May 2010.
eComStation version 2.1 GA was released on May 20, 2011.
IBM is still delivering defect support for a fee.
customers to migrate their often highly complex applications to
e-business technologies such as Java in a platform-neutral manner.
Once application migration is completed,
IBM recommends migration to a
different operating system, suggesting
Linux as an
This section needs to be updated. Please update this article to
reflect recent events or newly available information. (March 2016)
As of 2008[update], support for running
OS/2 under virtualization
appears to be improving in several third-party products.
historically been more difficult to run in a virtual machine than most
other legacy x86 operating systems because of its extensive reliance
on the full set of features of the x86 CPU; in particular, OS/2's use
of ring 2 prevented it from running in VMware. Emulators such as
Bochs don't suffer from this problem and can run
OS/2. A beta of VMWare Workstation 2.0 released in
January 2000 was the first hypervisor that could run
OS/2 at all.
Later, the company decided to drop official
Microsoft (originally Connectix) has been able to run
OS/2 without hardware virtualization support for many years. It also
provided “additions” code which greatly improves host-guest OS
interactions in OS/2. The additions are not provided with the current
version of VirtualPC, but the version last included with a release may
still be used with current releases. At one point,
OS/2 was a
supported host for
VirtualPC in addition to a guest. Note that OS/2
runs only as a guest on those versions of
VirtualPC that use
virtualization (x86 based hosts) and not those doing full emulation
VirtualPC for Mac).
Oracle Corporation (originally InnoTek, later Sun)
OS/2 Warp 3, 4 and 4.5 as well as eComStation as guests.
However, attempting to run
OS/2 and eComStation can still be
difficult, if not impossible, because of the strict requirements of
VT-x/AMD-V hardware-enabled virtualization and only ACP2/MCP2 is
reported to work in a reliable manner.
The difficulties in efficiently running
OS/2 have, at least once,
created an opportunity for a new virtualization company. A large bank
in Moscow needed a way to use
OS/2 on newer hardware that
OS/2 did not
support. As virtualization software is an easy way around this, the
company desired to run
OS/2 under a hypervisor. Once it was determined
VMware was not a possibility, it hired a group of Russian
software developers to write a host-based hypervisor that would
officially support OS/2. Thus, the
Parallels, Inc. company and their
Parallels Workstation was born.
NCR Corporation and
Diebold Incorporated have both adopted
Windows XP as their migration path from OS/2.
Diebold Incorporated initially shipped XP Embedded Edition
exclusively, but following extensive pressure from customer banks to
support a common OS, switched to XP Professional to match their
primary competitor NCR Corporation.
OS/2 has few native computer viruses; while it is not invulnerable
by design, its reduced market share appears to have discouraged virus
writers. There are, however, OS/2-based antivirus programs, dealing
DOS viruses and Windows viruses that could pass through an OS/2
Petitions for open source
Many people hoped that
IBM would release
OS/2 or a significant part of
it as open source. Petitions were held in 2005 and 2007, but IBM
refused them, citing legal and technical reasons. It is unlikely
that the entire OS will be open at any point in the future because it
contains third-party code to which
IBM does not have copyright, and
much of this code is from Microsoft.
IBM also once engaged in a
technology transfer with Commodore, licensing
Amiga technology for
OS/2 2.0 and above, in exchange for the
REXX scripting language.
This means that
OS/2 may have some code that was not written by IBM,
which can therefore prevent the OS from being re-announced as
open-sourced in the future. On the other hand,
REXX for Windows and
OS/2 to the Open Object
maintained by the
REXX Language Association on Sourceforge.
There was a petition, arranged by OS2World, to open parts of the OS.
Open source operating systems such as
Linux have already profited from
OS/2 indirectly through IBM's release of the improved JFS file system,
which was ported from the
OS/2 code base. As
IBM didn't release the
source of the
OS/2 JFS driver, developers ported the
Linux driver back
to eComStation and added the functionality to boot from a JFS
partition. This new JFS driver has been integrated into eComStation
v2.0, the successor of OS/2.
Summary of releases
Release dates refer to the US English editions unless otherwise
OS/2 2.0 LA (Limited Availability)
OS/2 for Windows
OS/2 2.11 SMP
OS/2 Warp Connect
OS/2 Warp Server 4
OS/2 Warp 4
OS/2 Warp Server Advanced SMP
WorkSpace On-Demand 1.0
WorkSpace On-Demand 2.0
OS/2 Warp Server for e-Business (version 4.50)
OS/2 Convenience Pack 1 (version 4.51)
OS/2 Convenience Pack 2 (version 4.52)
The graphic system has a layer named
Presentation Manager that manages
windows, fonts, and icons. This is similar in functionality to a
non-networked version of
X11 or the Windows GDI. On top of this lies
Workplace Shell (WPS) introduced in
OS/2 2.0. WPS is an
object-oriented shell allowing the user to perform traditional
computing tasks such as accessing files, printers, launching legacy
programs, and advanced object oriented tasks using built-in and
third-party application objects that extended the shell in an
integrated fashion not available on any other mainstream operating
system. WPS follows IBM's
Common User Access user interface standards.
Hardware vendors were reluctant to support device drivers for
alternative operating systems including
OS/2 and Linux, leaving users
with few choices from a select few vendors. To relieve this issue for
IBM licensed a reduced version of the Scitech display
drivers, allowing users to choose from a wide selection of cards
supported through Scitech's modular driver design.
WPS represents objects such as disks, folders, files, program objects,
and printers using the
System Object Model
System Object Model (SOM), which allows code to
be shared among applications, possibly written in different
programming languages. A distributed version called DSOM allowed
objects on different computers to communicate. DSOM is based on CORBA.
The object oriented aspect of SOM is similar to, and a direct
competitor to, Microsoft's Component Object Model, though it is
implemented in a radically different manner; for instance, one of the
most notable differences between SOM and COM is SOM's support for
inheritance (one of the most fundamental concepts of OO
programming)—COM does not have such support. SOM and DSOM are no
longer being developed.
OS/2 also includes a radical advancement in application development
with compound document technology called OpenDoc, which was developed
OpenDoc proved interesting as a technology, but was not
widely used or accepted by users or developers.
OpenDoc is also no
longer being developed.
The multimedia capabilities of
OS/2 are accessible through Media
Control Interface commands. The last update (bundled with the IBM
Netscape Navigator plugins) added support for
Support for newer formats like PNG, progressive JPEG, DivX, Ogg, MP3
comes from third parties. Sometimes it is integrated with the
multimedia system, but in other offers it comes as standalone
TCP/IP stack is based on the open source
BSD stack as visible with
SCCS what compatible tools.
Some problems were classic subjects of comparison with other operating
Synchronous input queue (SIQ): if a GUI application was not servicing
its window messages, the entire GUI system could get stuck and a
reboot was required. This problem was considerably reduced with later
Warp 3 fixpacks and refined by Warp 4, by taking control over the
application after it had not responded for several seconds.
No unified object handles (
OS/2 v2.11 and earlier): The availability
of threads probably led system designers to overlook mechanisms which
allow a single thread to wait for different types of asynchronous
events at the same time, for example the keyboard and the mouse in a
"console" program. Even though select was added later, it only worked
on network sockets. In case of a console program, dedicating a
separate thread for waiting on each source of events made it difficult
to properly release all the input devices before starting other
programs in the same "session". As a result, console programs usually
polled the keyboard and the mouse alternately, which resulted in
wasted CPU and a characteristic "jerky" reactivity to user input. In
IBM introduced a new call for this specific problem.
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OS/2 has been widely used in Iran Export Bank (Bank Saderat Iran) in
their teller machines, ATMs and local servers (over 30,000 working
stations). As of 2011, the bank moved to virtualize and renew their
infrastructure by moving
OS/2 to Virtual Machines running over
OS/2 was widely used in Brazilian banks.
Banco do Brasil
Banco do Brasil had a peak
10,000 machines running
OS/2 Warp in the 1990s.
OS/2 was used in
automated teller machines until 2006. The workstations and automated
teller machines and attendant computers have been migrated to
OS/2 has been used in the banking industry.
Suncorp bank in Australia
still ran its ATM network on
OS/2 as late as 2002. ATMs in Perisher
OS/2 as late as 2009, and even the turn of the decade.
OS/2 was widely adopted by accounting professionals and auditing
companies. In mid-1990s native
32-bit accounting software were well
developed and serving corporate markets.
OS/2 ran the faulty baggage handling system at Denver International
Airport. The OS was eventually scrapped, but the software written for
the system led to massive delays in the opening of the new airport.
The OS itself was not at fault, but the software written to run on the
OS. The baggage handling system was eventually removed.
OS/2 was used by radio personality Howard Stern. He once had a
10-minute on-air rant about
Windows 95 and recommended
OS/2. He also used
OS/2 on his
IBM 760CD laptop.
OS/2 was used as part of the Satellite Operations Support System
(SOSS) for NPR's Public Radio Satellite System. SOSS was a
computer-controlled system using
NPR member stations used to
receive programming feeds via satellite. SOSS was introduced in 1994
OS/2 3.0, and was retired in 2007, when
NPR switched over to its
successor, the ContentDepot.
OS/2 was used to control the SkyTrain automated light rail system in
Vancouver, British Columbia, Canada until the late 2000s when it was
replaced by Windows XP.
OS/2 was used in the
Jubilee Line Extension
Jubilee Line Extension Signals
Control System (JLESCS) in London, UK. This control system delivered
by Alcatel was in use from 1999 to 2011 i.e. between abandonment
before opening of the line's unimplemented original automatic train
control system and the present
SelTrac system. JLESCS did not provide
automatic train operation only manual train supervision. Six OS/2
local site computers were distributed along the railway between
Stratford and Westminster, the shunting tower at Stratford depot, and
several formed the central equipment located at Neasden. It was once
intended to cover the rest of the line between Green Park and Stanmore
but this was never introduced.
OS/2 has been used by
The Co-operative Bank
The Co-operative Bank in the UK for its domestic
call centre staff, using a bespoke program created to access customer
accounts which cannot easily be migrated to Windows.
OS/2 has been used by the Stop & Shop supermarket chain (and has
been installed in new stores as recently as March 2010).
OS/2 has been used on ticket machines for
Croydon Tramlink in
OS/2 has been used in New York City’s subway system for
OS/2 was used in checkout systems at Safeway supermarkets.
OS/2 was used by Trenitalia, both for the desktops at Ticket Counters
and for the Automatic Ticket Counters up to 2011. Incidentally, the
Automatic Ticket Counters with
OS/2 were more reliable than the
current ones running a flavor of Windows.
OS/2 was used as the main operating system for Abbey National General
Insurance motor and home direct call centre products using the PMSC
Series III insurance platform on DB2.2 from 1996-2001
BYTE in 1989 listed
OS/2 as among the "Excellence" winners of the BYTE
Awards, stating that it "is today where the Macintosh was in 1984:
It's a development platform in search of developers". The magazine
predicted that "When it's complete and bug-free, when it can really
use the 80386, and when more desktops sport OS/2-capable PCs, OS/2
will—deservedly—supersede DOS. But even as it stands,
OS/2 is a
In March 1995
OS/2 won seven awards
InfoWorld Product of the Year.
Five Awards at CeBIT.
PC Professional Magazine - Innovation of the Year award.
CHIP Magazine named
OS/2 Warp the Operating System of the Year.
DOS International named
OS/2 Warp the Operating System of the Year.
1+1 Magazine awarded it with the Software Marketing Quality award.
Industrie Forum awarded it with its Design Excellence.
SPA Best Business Software Award.
IBM products utilizing OS/2
IBM has used
OS/2 in a wide variety of hardware products, effectively
as a form of embedded operating system.
Nature of Product
Used as the operating system for the Library Manager (LM) that
controlled the tape accessor (robot)
Used as the operating system for the Service Processor (SP) and if
installed, the Network Node Processor (NNP).
The 3890/XP1 was announced November 12, 1988. It initially used OS/2
1.1 Extended Edition on a PS/2 Model 80 to emulate the stacker
control software that previously ran on a System 360.
Used in a range of Automatic Teller Machines manufactured by IBM. Was
also used in later 478x ATMs manufactured with Diebold.
Used as the operating system for the Support Element (SE). Was
also used in later mainframe models such as the
IBM 2064 and 2074.
History of the graphical user interface
Multiple Virtual DOS Machine (MVDM) -
DOS machine and
seamless Windows integration
^ Matthew Nawrocki (26 February 2013). "Preview: eComStation 2.2 Beta,
the legacy of
OS/2 lives on". TechRepublic. TechRepublic. Retrieved 22
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^ McCracken, Harry (April 2, 2012). "25 Years of IBM's OS/2: The
Strange Days and Surprising Afterlife of a Legendary Operating
System". Time Magazine. Retrieved 20 May 2017.
^ Markoff, John (June 28, 1992). "I.B.M. and
Operating-System Feud". The New York Times. Retrieved 20 May
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OS/2 1.3: Ten Years Ago". The History
of OS/2. Archived from the original on 2007-10-12.
IBM (12 July 2005). "Changes in support for
OS/2 Warp 4 and OS/2
Warp Server for e-business". ibm.com. Archived from the original on 27
^ James Sanders (2015). "OS/2: Blue Lion to be the next distro of the
^ James Sanders (2016). "
OS/2 resurrected: Blue Lion becomes ArcaOS,
details emerge for upcoming release".
^ Sharwood, Simon (19 May 2017). "What is dead may never die: a new
OS/2 just arrived". The Register.
Microsoft (1985). "Joint Development Agreement Between IBM
and Microsoft" (PDF). Retrieved March 25, 2013. [permanent dead
^ Michal Necasek (April 2, 1987). "
Microsoft Operating System/2 With
Presentation Manager Provides Foundation for Next Generation
of Personal Computer Industry". The History of
OS/2 (Press release).
Archived from the original on April 10, 2010. Retrieved March 25,
^ Michal Necasek (2001-07-16). "
OS/2 1.0". The History of OS/2.
Archived from the original on 2010-08-11.
^ a b David Both (May 2, 2012) [originally published December 19,
1996]. "A Short History of OS/2". Data
OS/2 Warp. Retrieved
April 9, 2013.
^ H. Gilbert (1995). "HPFS". Das Boot. PC Lube and Tune. Archived from
the original on 2006-07-14.
^ Bob Eager (28 October 2000). "Implementation of extended attributes
on the FAT file system". Tavi Systems.
^ Iacobucci, Ed; foreword by
Bill Gates (1988). "Foreword". OS/2
Programmer's Guide. McGraw-Hill Osborne Media.
ISBN 0-07-881300-X. I believe
OS/2 is destined to be the most
important operating system, and possibly program, of all time. As the
successor to DOS, which has over 10,000,000 systems in use, it creates
incredible opportunities for everyone involved with PCs.
^ Mary Bellis. "The Unusual History of the
^ Thomas Hormby (25 May 2005). "Windows History (1985–1994)".
osviews.com. Archived from the original on March 12, 2006. Retrieved
April 9, 2013.
^ Michal Necasek (2001-10-29). "
OS/2 1.1 and 1.2: The Early Years".
The History of OS/2. Archived from the original on 2006-06-13.
^ Paul Thurrott (24 January 2003). "
Windows Server 2003: The Road To
Gold". winsupersite.com. Archived from the original on 4 June
^ Gates, Bill; Myhrvold, Nathan; Rinearson, Peter. The Road Ahead.
^ Michael Lee Vasu; Debra W. Stewart; G. David Garson (1998-03-03).
Organizational behavior and public management. p. 268.
^ Gordon Letwin. ""What's happening to OS/2," a Usenet post by Gordon
Letwin from August 1995, the point of view of a
^ Gates, Bill. "
Bill Gates Interview". Computer History Collection
(transcript of a Video History interview). Interview with David
Allison. National Museum of American History, Smithsonian Institution.
Retrieved April 10, 2013.
Microsoft (2000). Inside Out, Microsoft—In Our Own Words. Warner
Business Books. ISBN 0-446-52739-4.
^ Microsoft. "Compatibility of OS/2-based Applications and APIs".
Microsoft TechNet. Microsoft. Retrieved April 9, 2013.
^ Robert X. Cringely (27 April 2006). "Killer Apps: For Apple's
Windows Strategy to Work, It Must Replace
Microsoft Office and Buy
Adobe Systems". pbs.org.
Microsoft (6 November 1999). "
Windows 3.1 Standard Mode and the
VCPI". support.microsoft.com. Archived from the original on March 9,
^ Christian Alice Scarborough (15 September 1998). "Team OS/2
Frequently Asked Questions".
OS/2 Games Setting Archive". Game Zero magazine. 6 March
^ Timothy F. Sipples (20 February 1995). "
OS/2 Warp Frequently Asked
^ "Biography for Kate Mulgrew".
Internet Movie Database. In 1996, was
IBM to help promote the latest release of
version 4 (previously codenamed Merlin), due to associations with Star
^ "In Search of Stupidity, Excerpts from Chapter 6".
Insearchofstupidity.com. Retrieved April 9, 2013.
^ Chapman, Merrill R. In Search of Stupidity: Over 20 Years of
High-tech Marketing Disasters (paperback) (2nd ed.). Berkeley,
California: Apress. ISBN 9781590597217. OCLC 71275572. Lay
summary – Amazon. They rented a hall in
New York City
New York City and invited
hundreds to see Patrick Stewart, the then current captain of the
Starship Enterprise to help roll out the product in a gala event.
(Stewart was a no-show.)
^ Lewis, Peter H. (8 August 1995). "PERSONAL COMPUTERS;
OS/2 No Longer
at Home at Home". The New York Times.
^ Wasserman, Elizabeth (June 8, 1999). "MS/DoJ:
yank Smart Suite". PC World.
^ "C. The Similar Experiences of Other Firms in Dealing with
Microsoft". Albion.com. Retrieved 2013-03-20.
^ Fleisch, Brett D; Allan, Mark (September 23, 1997). "Workplace
Microkernel and OS: A Case Study". John Wiley & Sons, Ltd.
Archived from the original on August 24, 2007. Retrieved March 25,
^ "OS2 World Community Forum – Index". Os2world.com. Retrieved
^ a b IBM. "End of Standard Support".
^ "News :: eComStation 2.0 GA to be Released for Warpstock Europe
2010". eComStation. Retrieved 2013-03-20.
^ "News :: eComStation 2.1 GA available". eComStation. Retrieved
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^ "Migration Station". Archived from the original on May 13, 2010.
Retrieved April 9, 2013.
OS/2 Server Transition". Redbooks.ibm.com.
2003-10-06. Archived from the original on 2014-02-01. Retrieved
^ "3346/GEN/K (1–32) (Page 1)" (PDF). Retrieved 2013-03-20.
VMware Team. "A Notice to
OS/2 Users". Archived from the
original on 2006-04-20.
^ VirtualBox. "
^ Timothy Prickett Morgan. "Breaking News—Parallels Joins the PC and
Server Virtualization Fray". itjungle.com. Archived from the original
^ John F. Morar, David M. Chess. "the effect of computer viruses on
OS/2 and Warp". research.ibm.com. Archived from the original on
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Retrieved April 9, 2013.
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^ The Art of
Unix Programming p. 66 ISBN 0-13-142901-9,
^ "Open Object
REXX FAQ". Retrieved 2011-07-05.
OS/2 Museum. Retrieved 2016-12-19.
^ "PC Magazine (archives scanned by Google)" (PDF). PC Magazine.
Linux Client Transition" (PDF).
IBM redbook. 2004.
p. 9. Archived from the original (PDF) on 2011-11-24. Retrieved
IBM Developer Connection for OS/2, Internal Fixpack 12J
^ KbdGetConsole() and DosWaitMuxWaitSem(), see Control Program
Programming Guide and Reference,
^ "Brazilian banks look to
Linux for ATMs". [permanent dead link]
^ "NetIQ Manages Over 1000 Windows Servers for One of Australia's
Largest Banks; ANZ Bank Completes Roll Out of NetIQ Management
Software to 1,300 Servers" (fee). Business Wire. January 24, 2002.
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Strange Days and Surprising Afterlife of a Legendary Operating
System". Technologizer. Time.com. Retrieved April 9, 2013.
BYTE Awards". BYTE. January 1989. p. 327.
^ "IBM's Developer Support News 1995 Issue 4".
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^ "Support Element Operations Guide". Retrieved 30 December
IBM 2074 Model 2 Console Support Controller — Consolidating and
Streamlining Console Support Function". Retrieved 19 June 2014.
Harvey M. Deitel and Michael S. Kogan (1992). The Design of OS/2.
Addison Wesley. ISBN 0-201-54889-5.
Letwin, Gordon (1988). Inside OS/2.
Pascal, Zachary (1994). Showstopper! The Breakneck Race to Create
Windows NT and the Next Generation at Microsoft. Warner Books.
Peter Moylan (2004-07-23). "Some fundamental
Michal Necasek (2005-12-03). "
PowerPC Edition". The History
of OS/2. Archived from the original on August 12, 2010. Retrieved
April 10, 2013. —Necasek discusses an aborted port to PowerPC
Reimer, Jeremy. "Half an operating system: The triumph and tragedy of
OS/2". Retrieved 12 December 2013.
os2world.com – Community of
ecomstation.ru – Community of eComStation and
netlabs.org – OpenSource Software for
OS/2 and eCS
hobbes.nmsu.edu – The
OS/2 software repository
EDM/2 – The source for
eCSoft/2 – The
OS/2 and eComstation software guide
osFree an open source project to build an
OS/2 clone operating system
Voyager Project, a defunct project to reimplement
OS/2 on modern
Linux API porting project
OS/2 API implementation for Windows
Microsoft documentation of
OS/2 API compatibility with Windows NT
The History of OS/2
Technical details of OS/2
OS/2 Warp 4 Installation and Update Manual; with boot disks and many
History of IBM
Mergers and acquisitions
IBM Power Systems
Information Management Software
Tivoli Software: Service Automation Manager
Criminal Reduction Utilising Statistical History
Center for The Business of Government
The Weather Company
The Weather Company (Weather Underground)
1250 René-Lévesque, Montreal, QC
One Atlantic Center, Atlanta, GA
Rome Software Lab
Toronto Software Lab
330 North Wabash, Chicago, IL
Thomas J. Watson
Thomas J. Watson Center, New York
Cambridge Scientific Center
Canada Head Office Building
Somers Office Complex
Academy of Technology
Centers for Advanced Studies: CASCON
The Great Mind Challenge
Linux Technology Center
IBM Virtual Universe Community
World Community Grid
Automated teller machine
Hard disk drive
Universal Product Code
Magnetic stripe card
Sabre airline reservation system
Scanning tunneling microscope
Globally Integrated Enterprise
Commercial Processing Workload
Thomas J. Watson
Thomas J. Watson (1914–1956)
Thomas Watson Jr.
Thomas Watson Jr. (1956–1971)
T. Vincent Learson
T. Vincent Learson (1971–1973)
Frank T. Cary (1973–1981)
John R. Opel (1981–1985)
John Fellows Akers (1985–1993)
Louis V. Gerstner Jr.
Louis V. Gerstner Jr. (1993–2002)
Samuel J. Palmisano
Samuel J. Palmisano (2002–2011)
Ginni Rometty (2012–present)
Board of directors
William R. Brody
Michael L. Eskew
Shirley Ann Jackson
Andrew N. Liveris
James W. Owens
Samuel J. Palmisano
Virginia M. Rometty
Joan E. Spero
A Boy and His Atom
Common Public License/
IBM Public License
IBM and the Holocaust
IBM international chess tournament
Operating systems by Microsoft
Nokia Asha platform
Windows 10 Mobile
Microsoft Windows family
Windows 95 (Development)
Windows NT 3.1
Windows NT 3.5
Windows NT 3.51
Windows NT 4.0
HPC Server 2008
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Home Server 2011
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Windows Preinstallation Environment
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