Editing OS/2 (section)

===1985–1990: Joint IBM–Microsoft development===

{{multiple image
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| image1            = OS-2 1.x logo glowing.svg
| caption1          = Logo of OS/2 1.x
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| caption2          = OS/2 1.0 featured a text-mode interface similar to MS-DOS.
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The development of OS/2 began when IBM and Microsoft signed the "Joint Development Agreement" in August 1985.<ref>{{Cite web|title=Joint Development Agreement Between International Business Machines Corporation And Microsoft Corporation|url=https://www.tech-insider.org/personal-computers/research/acrobat/871126.pdf|url-status=live|archive-url=https://web.archive.org/web/20210815044103/https://www.tech-insider.org/personal-computers/research/acrobat/871126.pdf|archive-date=August 15, 2021|access-date=August 15, 2021|website=Tech Insider}}</ref><ref name="JointAgreementPR">{{cite press release| title=Microsoft Operating System/2 With Windows Presentation Manager Provides Foundation for Next Generation of Personal Computer Industry|author=Michal Necasek| work=The History of OS/2| date=April 2, 1987| archive-date=April 10, 2010| access-date=March 25, 2013| url=http://pages.prodigy.net/michaln/history/pr/87apr_m3592.html|archive-url=https://web.archive.org/web/20100410013835/http://pages.prodigy.net/michaln/history/pr/87apr_m3592.html |url-status=dead}}</ref> It was code-named "CP/DOS" and it took two years for the first product to be delivered.

====OS/2 1.0 (1987){{anchor|1.0}}====
OS/2's release was long delayed. It was widely believed that all IBM programmers used [[assembly language]], and a rumor said that the delay was because they had to learn [[C (language)|C]].<ref name="vose198807">{{Cite magazine |last=Vose |first=G. Michael |date=July 1988 |title=Reader's Guide to OS/2 |url=https://archive.org/details/byte-1988-07_202104/page/51/mode/1up?view=theater |access-date=2025-04-12 |department=Book Reviews |magazine=[[Byte (magazine)|Byte]] |pages=51-54}}</ref> OS/2 1.0 was announced in April 1987 and released in December. The original release only ran in [[text mode]], and a GUI was introduced with OS/2 1.1 about a year later. OS/2 features an [[Application programming interface|API]] for controlling the [[display device|video display]] (VIO) and handling [[computer keyboard|keyboard]] and mouse events so that programmers writing for [[protected mode]] need not call the [[BIOS]] or access hardware directly. Other development tools included a subset of the video and keyboard APIs as linkable libraries so that family mode programs are able to run under MS-DOS,{{citation needed|date=April 2019}} and, in the OS/2 Extended Edition v1.0, a database engine called Database Manager or DBM (this was related to [[DB2]], and should not be confused with the [[DBM (computing)|DBM]] family of database engines for Unix and [[Unix-like]] operating systems).<ref>{{cite web|url=http://users.informatik.uni-halle.de/~brass/zert08/c1_produ.pdf|title=DBA Certification Course (Summer 2008) Chapter 1: DB2 Products and Tools|website=Users.informatik.uni-halle.de|access-date=2 April 2019}}</ref> A task-switcher named Program Selector was 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).<ref>{{cite web|title=OS/2 1.0|author=Michal Necasek|work=The History of OS/2|date=2001-07-16|url=http://pages.prodigy.net/michaln/history/os210/index.html|url-status=dead|archive-url=https://web.archive.org/web/20100811211529/http://pages.prodigy.net/michaln/history/os210/index.html|archive-date=2010-08-11}}</ref>

Communications and database-oriented extensions were delivered in 1988, as part of OS/2 1.0 Extended Edition: [[Systems Network Architecture|SNA]], [[X.25]]/[[Advanced Program-to-Program Communication|APPC]]/LU 6.2, [[LAN Manager]], [[Query Management Facility|Query Manager]], SQL.

[[File:Os2-1.1-desktop.png|thumb|right|OS/2 1.1 was the first version to feature the Presentation Manager GUI.]]

====OS/2 1.1 (1988){{anchor|1.1}}====
The promised user interface, [[Presentation Manager]], was introduced with OS/2 1.1 in October 1988.<ref name="Both1996">{{cite web|title=A Short History of OS/2|author=David Both|work=DataBook for OS/2 Warp|date=May 2, 2012|orig-year=originally published December 19, 1996|url=http://www.databook.bz/?page_id=223|access-date=April 9, 2013|archive-url=https://web.archive.org/web/20130218111519/http://www.databook.bz/?page_id=223|archive-date=February 18, 2013|url-status=dead}}</ref> It had a similar user interface to [[Windows 2.1x|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 [[Windows 3.0]].)

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.

====OS/2 1.2 (1989){{anchor|1.2|1.21}}====
In 1989, Version 1.2 introduced Installable Filesystems and, notably, the [[High Performance File System|HPFS]] [[File system|filesystem]]. HPFS provided a number of improvements over the older [[File Allocation Table|FAT]] file system, including long filenames and a form of [[Fork (file system)|alternate data streams]] called [[Extended Attributes]].<ref>{{cite web|title=HPFS|author=H. Gilbert|work=Das Boot|publisher=PC Lube and Tune|year=1995|url=http://www.yale.edu/pclt/BOOT/HPFS.htm|url-status=dead|archive-url=https://web.archive.org/web/20060714193222/http://www.yale.edu/pclt/BOOT/HPFS.htm|archive-date=2006-07-14|access-date=2006-06-09}}</ref> In addition, extended attributes were also added to the FAT file system.<ref>{{cite web|title=Implementation of extended attributes on the FAT file system|author =Bob Eager|work=Tavi Systems|date=28 October 2000|url=http://www.tavi.co.uk/os2pages/eadata.html}}</ref>

[[Image:MS-OS2-v1.0-diskettes.jpg|left|thumb|Installation Disk A of Microsoft OS/2 1.3 (3½-inch floppy disk)]]

The Extended Edition of 1.2 introduced [[Internet protocol suite|TCP/IP]] and [[Ethernet]] support.

OS/2- and Windows-related books of the late 1980s from both Microsoft's [[Gordon Letwin]] and his IBM counterpart [[Ed Iacobucci]] acknowledged the existence of both systems and promoted OS/2 as the system of the future.<ref>{{cite book|last=Iacobucci|first=Ed|author-link=Ed Iacobucci|author2=foreword by [[Bill Gates]]|title=OS/2 Programmer's Guide|year=1988| publisher=[[McGraw-Hill Osborne Media]]|chapter=Foreword|isbn=0-07-881300-X|quote=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.}}</ref>{{r|vose198807}}