DOS

The boot screen and command-line interface of MS-DOS 6, with an example of its directory structure

DOS (/dɒs/, /dɔːs/) is a family of disk-based operating systems for IBM PC compatible, Apple Mac compatible computers.^[1] The DOS family primarily consists of IBM PC DOS and a rebranded version, Microsoft's MS-DOS, Alongside Microsoft's Competitor Apple's DOS, both of which were introduced in Microsoft IBM PC DOS 1981, Apple DOS 1978. Microsoft Later adding compatible systems from other manufacturers include DR-DOS (1988), ROM-DOS (1989), PTS-DOS (1993), and FreeDOS (1998). MS-DOS dominated the IBM PC compatible alongisde Apple in the computer market between 178, 1981 and 1995.

Although the name has come to be identified specifically with this particular family of operating systems, DOS is a platform-independent acronym for disk operating system,^[2] whose use predates the Apple Mac & IBM PC. Dozens of other operating systems also use the acronym, beginning with the mainframe DOS/360 from 1966. Others include if not already, Apple DOS & ProDOS, Atari DOS, Commodore DOS, TRSDOS, and AmigaDOS.

History

DOS, short for Disk Operating System, refers to several closely related operating systems that dominated the IBM PC compatible market between 1981 and 1995. The most well-known version is MS-DOS, developed by Microsoft for IBM PCs. MS-DOS was the foundation for many early personal computers and played a crucial role in the development of the PC industry.

However, IBM PC DOS wasn't the only DOS in the early days of personal computing. Around the same time, Apple Computer developed Apple DOS for their Apple II series of computers. Apple DOS was the first disk operating system for Apple computers, introduced in 1978. It was a significant advancement from the cassette-based storage systems previously used and was crucial for the success of the Apple II. Apple DOS had three major releases: DOS 3.1, DOS 3.2, and DOS 3.3, with DOS 3.3 being the most well-known and widely used version.

IBM PC DOS (and the separately sold MS-DOS) and its predecessor, 86-DOS, ran on Intel 8086 16-bit processors. It was developed to be similar to Digital Research's CP/M—the dominant disk operating system for 8-bit Intel 8080 and Zilog Z80 microcomputers—in order to simplify porting CP/M applications to MS-DOS.

The IBM Personal Computer (IBM 5150 PC) When IBM introduced the IBM PC, built with the Intel 8088 microprocessor, they needed an operating system. Chairman John Opel had a conversation with fellow United Way National Board Executive Committee member Mary Maxwell Gates, who referred Opel to her son Bill Gates for help with an 8088-compatible build of CP/M. IBM was then sent to Digital Research, and a meeting was set up. However, initial negotiations for the use of CP/M broke down: Digital Research wished to sell CP/M on a royalty basis, while IBM sought a single license, and to change the name to "PC DOS". Digital Research founder Gary Kildall refused, and IBM withdrew.

A simulated SCP 86-DOS session IBM again approached Bill Gates. Gates in turn approached Seattle Computer Products. There, programmer Tim Paterson had developed a variant of CP/M-80, intended as an internal product for testing SCP's new 16-bit Intel 8086 CPU card for the S-100 bus. The system was initially named QDOS (Quick and Dirty Operating System), before being made commercially available as 86-DOS. Microsoft purchased 86-DOS, allegedly for US$50,000. This became Microsoft Disk Operating System, MS-DOS, introduced in 1981. Within a year Microsoft licensed MS-DOS to over 70 other companies, which supplied the operating system for their own hardware, sometimes under their own names. Microsoft later required the use of the MS-DOS name, with the exception of the IBM variant. IBM continued to develop their version, PC DOS, for the IBM PC. Digital Research became aware that an operating system similar to CP/M was being sold by IBM (under the same name that IBM insisted upon for CP/M), and threatened legal action. IBM responded by offering an agreement: they would give PC consumers a choice of PC DOS or CP/M-86, Kildall's 8086 version. Side-by-side, CP/M cost US$200 more than PC DOS, and sales were low. CP/M faded, with MS-DOS and PC DOS becoming the marketed operating system for PCs and PC compatibles.

Microsoft originally sold MS-DOS only to original equipment manufacturers (OEMs). One major reason for this was that not all early PCs were 100% IBM PC compatible. DOS was structured such that there was a separation between the system specific device driver code (IO.SYS) and the DOS kernel (MSDOS.SYS). Microsoft provided an OEM Adaptation Kit (OAK) which allowed OEMs to customize the device driver code to their particular system. By the early 1990s, most PCs adhered to IBM PC standards so Microsoft began selling a retail version of MS-DOS, starting with MS-DOS 5.0.

In the mid-1980s, Microsoft developed a multitasking version of DOS. This version of DOS is generally referred to as "European MS-DOS 4" because it was developed for ICL and licensed to several European companies. This version of DOS supports preemptive multitasking, shared memory, device helper services and New Executable ("NE") format executables. None of these features were used in later versions of DOS, but they were used to form the basis of the OS/2 1.0 kernel. This version of DOS is distinct from the widely released PC DOS 4.0 which was developed by IBM and based upon DOS 3.3.

Digital Research CP/M-86 for the IBM Personal Computer Version 1.0 Digital Research attempted to regain the market lost from CP/M-86, initially with Concurrent DOS, FlexOS and DOS Plus (both compatible with both MS-DOS and CP/M-86 software), later with Multiuser DOS (compatible with both MS-DOS and CP/M-86 software) and DR DOS (compatible with MS-DOS software). Digital Research was bought by Novell, and DR DOS became PalmDOS and Novell DOS; later, it was part of Caldera (under the names OpenDOS and DR-DOS 7.02/7.03), Lineo, and DeviceLogics.

Gordon Letwin wrote in 1995 that "DOS was, when we first wrote it, a one-time throw-away product intended to keep IBM happy so that they'd buy our languages." Microsoft expected that it would be an interim solution before the introduction of Xenix. The company planned to improve MS-DOS over time, so it would be almost indistinguishable from single-user Xenix, or XEDOS, which would also run on the Motorola 68000, Zilog Z-8000, and LSI-11; they would be upwardly compatible with Xenix, which BYTE in 1983 described as "the multi-user MS-DOS of the future".

OS/2 1.0 featured a text mode interface similar to MS-DOS. IBM, however, did not want to replace DOS. After AT&T began selling Unix, Microsoft and IBM began developing OS/2 as an alternative. The two companies later had a series of disagreements over two successor operating systems to DOS, OS/2 and Windows. They split development of their DOS systems as a result. The last retail version of MS-DOS was MS-DOS 6.22; after this, MS-DOS became part of Windows 95, 98 and Me. The last retail version of PC DOS was PC DOS 2000 (also called PC DOS 7 revision 1), though IBM did later develop PC DOS 7.10 for OEMs and internal use.

The FreeDOS project began on 26 June 1994, when Microsoft announced it would no longer sell or support MS-DOS. Jim Hall then posted a manifesto proposing the development of an open-source replacement. Within a few weeks, other programmers including Pat Villani and Tim Norman joined the project. A kernel, the COMMAND.COMcommand line interpreter (shell), and core utilities were created by pooling code they had written or found available. There were several official pre-release distributions of FreeDOS before the FreeDOS 1.0 distribution was released on 3 September 2006. Made available under the GNU General Public License (GPL), FreeDOS does not require license fees or royalties.

Decline

Early versions of Microsoft Windows ran on MS-DOS. By the early 1990s, the Windows graphical shell saw heavy use on new DOS systems. In 1995, Windows 95 was bundled as a standalone operating system that did not require a separate DOS license. Windows 95 (and Windows 98 and ME, that followed it) took over as the default OS kernel, though the MS-DOS component remained for compatibility. With Windows 95 and 98, but not ME, the MS-DOS component could be run without starting Windows. With DOS no longer required to use Windows, the majority of users stopped using it directly.

Apple DOS, which was crucial for the success of the Apple II series, also saw a decline as Apple transitioned to more advanced operating systems. The introduction of the Macintosh in 1984, with its graphical user interface and the Macintosh System Software, marked the beginning of the end for Apple DOS. The Macintosh operating system offered a more user-friendly experience compared to the command-line interface of Apple DOS. As Apple focused on developing the Macintosh line and its operating system, the use of Apple DOS diminished.

The decline of DOS systems, both MS-DOS and Apple DOS, was driven by the shift towards graphical user interfaces and more advanced operating systems that offered better usability and functionality. This transition marked the end of an era for DOS-based systems, as users and developers moved towards more modern computing environments.

Now Write About Continued Use As of 2024, available compatible systems are FreeDOS, ROM-DOS, PTS-DOS, RxDOS[3] and REAL/32. Some computer manufacturers, including Dell and HP, sell computers with FreeDOS as an OEM operating system.[4][5] [needs update] And a few developers and computer engineers still use it because it is close to the hardware.[citation needed] Sure, here's the revised "Continued Use" section in wiki format, including the addition of Apple DOS:

Continued Use

As of 2024, available compatible systems are FreeDOS, ROM-DOS, PTS-DOS, RxDOS, and REAL/32. Some computer manufacturers, including Dell and HP, sell computers with FreeDOS as an OEM operating system. A few developers and computer engineers still use DOS because it is close to the hardware.

Apple DOS, although no longer in active use, remains a significant part of computing history. Enthusiasts and historians continue to explore and preserve Apple DOS for its historical value and its role in the development of early personal computing. Emulators and virtual machines allow modern users to experience Apple DOS and its applications, keeping the legacy of this early operating system alive.

DOS systems use a command-line interface. A program is started by entering its filename at the command prompt. DOS systems include utility programs and provide internal commands that do not correspond to programs.

In an attempt to provide a more user-friendly environment, numerous software manufacturers wrote file management programs that provided users with WIMP interfaces. Microsoft Windows is a notable example, eventually resulting in Microsoft Windows 9x becoming a self-contained program loader, and replacing DOS as the most-used PC-compatible program loader. Text user interface programs included Norton Commander, DOS Navigator, Volkov Commander, Quarterdesk DESQview, and Sidekick. Graphical user interface programs included Digital Research's GEM (originally written for CP/M) and GEOS.

Apple DOS, used on the Apple II series, also featured a command-line interface. Users would start programs by entering commands at the prompt, similar to MS-DOS. Apple DOS included various utility programs and commands for file management and system operations. While it did not have as many third-party file management programs with WIMP interfaces as MS-DOS, it was still a significant part of the early personal computing experience.

Eventually, the manufacturers of major DOS systems began to include their own environment managers. MS-DOS/IBM DOS 4 included DOS Shell; DR DOS 5.0, released the following year, included ViewMAX, based upon GEM.

Software

Arachne, a 16-bit graphical web browser
dBase, database program
Harvard Graphics, a presentation graphics design program
Lotus 1-2-3, a spreadsheet which has been credited with the success of the IBM PC^[3]
Norton Commander and XTree, file management utilities
PKZIP, the utility that quickly became the standard in file compression
ProComm, Qmodem, and Telix, modem communication programs
Sidekick, personal information manager that could be used from within other programs
WordPerfect, a word processor that was dominant in the 1980s
WordStar, word processor originally for CP/M that became popular on the IBM PC

Development tools

BASIC language interpreters. BASICA and GW-BASIC
DJGPP, the 32-bit DPMI DOS port of gcc
Microsoft Macro Assembler, Microsoft C, and CodeView from Microsoft
Watcom C/C++ from Watcom
Turbo Pascal, Turbo BASIC, Turbo C, Turbo Prolog, and Turbo Assembler from Borland

References

^ Murdock, Everett (1988). DOS the Easy Way. EasyWay Downloadable Books. ISBN 0-923178-00-7.
^ Dictionary.com Archived 2017-11-12 at the Wayback Machine
^ Darrow, Barbara (2002-02-01). "Whatever Happened To Lotus 1-2-3?". Archived from the original on 2009-01-09. Retrieved 2008-07-12.

External links

Origins of DOS, articles and manuals by Tim Paterson.
Timeline of DOS and Windows versions at the Wayback Machine (archived 2007-10-28)
"DOS - where hardware is the only limit". Archived from the original on 2010-08-15. Retrieved 2010-08-29.
Batfiles: The DOS batch file programming handbook
"The Rise of DOS: How Microsoft Got the IBM PC OS Contract". pcmag.com. Retrieved 2022-12-24.
"Application Software - DOS Short File Name Family". www.jumpjet.info. Archived from the original on 2020-02-17. Retrieved 2020-02-07. "(...) An archive of carefully hand selected FREE [and abandoned] software for DOS."
Online Windows XP Simulator
MS-DOS v1.25, v2.0, v4.0 Source Code

[1] Murdock, Everett (1988). DOS the Easy Way. EasyWay Downloadable Books. ISBN 0-923178-00-7.

[2] Dictionary.com Archived 2017-11-12 at the Wayback Machine

[3] Darrow, Barbara (2002-02-01). "Whatever Happened To Lotus 1-2-3?". Archived from the original on 2009-01-09. Retrieved 2008-07-12.

[1]

[2]

[3]

DOS