* Attached Support Processor, one of the two early IBM System / 360 programs that replaces the native SPOOL facilities of OS / 360 ; the other was Houston Automatic Spooling Priority ( HASP ).

With ASP Version 3 the name was changed to Asymmetric Multiprocessor and support was added for OS / VS2 ( SVS ).

* Auxiliary Storage Pool, a group of disk drives in the IBM i ( aka OS / 400 ) operating system

Three emulators of the machine exist, ElectrEm for Windows / Linux / Mac OS X, Elkulator for Windows / DOS and the Multi-system emulator MESS.

The rise of TCP / IP during the 1990s led to a re-implementation of most of these types of support on that protocol, and AppleTalk became unsupported as of the release of Mac OS X v10. 6 in 2009.

| ATA / ATAPI-8 || ATA-8 || — || || Hybrid drive featuring non-volatile cache to speed up critical OS files || In progress

( Around 1990, OS / 2 came out with " preemptive multitasking " of DOS, an alternative to DESQview for multi-node BBS.

By 1995, many of the DOS-based BBSes had begun switching to modern multitasking operating systems, such as OS / 2, Windows 95, and Linux.

JPI first launched a MS-DOS compiler named JPI Modula-2, that later became TopSpeed Modula-2, and followed up with TopSpeed C, TopSpeed C ++ and TopSpeed Pascal compilers for both the MS-DOS and OS / 2 operating systems.

MS-DOS and Win16 subsystems ( only on i386 ) can run some applications for those platforms, and it has an OS / 2 subsystem for running CLI OS / 2 applications.

IBM contributed its Common User Access model from OS / 2's Workplace Shell.

OS / 390 or its successor, z / OS, display dates in yy. ddd format for most operations.

* On systems that support one-button mice, context menus are typically opened by pressing and holding the primary mouse button ( this works on the icons in the Dock on Mac OS X ) or by pressing a keyboard / mouse button combination ( e. g. Ctrl-mouse click in Mac OS ).

Debian GNU / Linux, which includes the GNU OS tools and Linux kernel, is a popular and influential Linux distribution.

* Open Dylan-Host of two open source, optimizing Dylan compilers targeting Unix / Linux, Mac OS X, and Microsoft Windows

EFI booting has been supported in only Microsoft Windows versions supporting GPT, the Linux kernel 2. 6. 1 and later, and Mac OS X on Intel-based Macs.

; Macintosh Common Lisp: Version 5. 2 for Apple Macintosh computers with a PowerPC processor running Mac OS X is open source.

* Installable File System ( IFS ) – a filesystem API for IBM OS / 2 and Microsoft Windows NT

Originally developed on IRIX, Freeciv has been ported to many different operating systems: it is distributed with many Linux distributions, offers installers for Microsoft Windows, and has been known to run on Mac OS X, Solaris, Ultrix, QNX, OS / 2, Cygwin, AmigaOS, RISC OS, Maemo, ZETA, SkyOS and various BSDs.

This allowed the game to be ported to different platforms such as Linux and OS / 2 ( EComStation ).

Modern Windows operating system versions are based on the newer Windows NT kernel that was originally intended for OS / 2.

Version 2. 03, and later 3. 0, faced challenges from Apple over its overlapping windows and other features Apple charged mimicked the ostensibly copyrighted " look and feel " of its operating system and " embodie and generated a copy of the Macintosh " in its OS.

OS / 2 logo

During the mid to late 1980s, Microsoft and IBM had cooperatively been developing OS / 2 as a successor to DOS.

OS / 2 would take full advantage of the aforementioned protected mode of the Intel 80286 processor and up to 16 MB of memory.

OS / 2 1. 0, released in 1987, supported swapping and multitasking and allowed running of DOS executables.

A GUI, called the Presentation Manager ( PM ), was not available with OS / 2 until version 1. 1, released in 1988.

Microsoft wanted to further develop Windows, while IBM desired for future work to be based on OS / 2.

In an attempt to resolve this tension, IBM and Microsoft agreed that IBM would develop OS / 2 2. 0, to replace OS / 2 1. 3 and Windows 3. 0, while Microsoft would develop a new operating system, OS / 2 3. 0, to later succeed OS / 2 2. 0.

Support was added to OS X in order to provide support for the large number of existing AppleTalk devices, notably laser printers and file shares, but alternate connection solutions common in this era, notably USB for printers, limited their demand.

AppleTalk support was finally removed from the MacOS in Mac OS X v10. 6 in 2009.

Frederick Phillips Brooks, Jr. ( born April 19, 1931 ) is a software engineer and computer scientist, best known for managing the development of IBM's System / 360 family of computers and the OS / 360 software support package, then later writing candidly about the process in his seminal book The Mythical Man-Month.

In response to the impending release of OS / 2 2. 0, Microsoft developed Windows 3. 1, which included several minor improvements to Windows 3. 0 ( such as display of TrueType scalable fonts, developed jointly with Apple ), but primarily consisted of bugfixes and multimedia support.

Chicago was designed to have support for 32-bit preemptive multitasking like OS / 2 and Windows NT, although a 16-bit kernel would remain for the sake of backward compatibility.

While OS / 2 continued to run Windows 3. 1 applications, it lacked support for anything but the Win32s subset of Win32 API ( see above ).

In the case of Mac OS X, the driver appears not to support file fragmentation at all ( i. e. it only supports ISO 9660 Level 2 but not Level 3 ).

Todd Hollenshead has also expressed support for Linux: " All said, we will continue to be a leading supporter of the Linux platform because we believe it is a technically sound OS and is the OS of choice for many server ops.

MINIX 3 also has support for virtual memory management, making it suitable for desktop OS use.

First released in 1974, MVS was extended by program products with new names multiple times, first to MVS / SE ( System Extension ), next to MVS / SP ( System Product ) Version 1, next to MVS / XA ( eXtended Architecture ), next to MVS / ESA ( Enterprise Systems Architecture ), next to OS / 390 and finally to z / OS ( when 64-bit support was added with the zSeries models ).

Software upgrades usually require setting up the operating system or portions thereof, and are non-disruptive only when using virtualizing facilities such as IBM's Z / OS and Parallel Sysplex, or Unisys ' XPCL, which support workload sharing so that one system can take over another's application while it is being refreshed.

It was the final version of Mac OS X to support the PowerPC architecture.

Mac OS X v10. 6 also features Microsoft Exchange Server support for Mail, iCal, and Address Book, new 64-bit technology capable of supporting greater amounts of RAM, an all new QuickTime X with a refreshed user interface and more functionality that used to be only available to QuickTime Pro owners.

An update introduced support for the Mac App Store, Apple's digital distribution platform for OS X applications.

OS / 2 is no longer marketed by IBM, and IBM standard support for OS / 2 was discontinued on 31 December 2006.

* 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 wanted.

Windows NT's OS / 2 heritage can be seen in its initial support for the HPFS filesystem, text mode OS / 2 1. x applications, and OS / 2 LAN Manager network support.