The Multiuser DOS Federation (MDOS) was an industry alliance to promote the growth and acceptance of multi-user

DOS DOS is shorthand for the MS-DOS and IBM PC DOS family of operating systems. DOS may also refer to: Computing * Data over signalling (DoS), multiplexing data onto a signalling channel * Denial-of-service attack (DoS), an attack on a communicat ...

-based solutions on

286 __NOTOC__ Year 286 ( CCLXXXVI) was a common year starting on Friday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Maximus and Aquilinus (or, less frequently, year 1039 ...

386 __NOTOC__ Year 386 ( CCCLXXXVI) was a common year starting on Thursday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Honorius and Euodius (or, less frequently, year 11 ...

and

486 __NOTOC__ Year 486 ( CDLXXXVI) was a common year starting on Wednesday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Basilius and Longinus (or, less frequently, year 12 ...

computers. It was formed in July 1990. Initially among them were

Digital Research Digital Research, Inc. (DR or DRI) was a company created by Gary Kildall to market and develop his CP/M operating system and related 8-bit, 16-bit and 32-bit systems like MP/M, Concurrent DOS, FlexOS, Multiuser DOS, DOS Plus, DR DOS ...

Theos Software THEOS, which translates from Greek as "God", is an operating system which started out as OASIS, a microcomputer operating system for small computers that use the Z80 processor. When the operating system was launched for the IBM Personal Comp ...

, SunRiver,

DigiBoard Digi International is an American Industrial Internet of Things (IIoT) technology company headquartered in Hopkins, Minnesota. The company was founded in 1985 and went public as Digi International in 1989. The company initially offered intellige ...

Alloy An alloy is a mixture of chemical elements of which at least one is a metal. Unlike chemical compounds with metallic bases, an alloy will retain all the properties of a metal in the resulting material, such as electrical conductivity, ductilit ...

, Viewport International and others. The idea was to reduce costs by allowing workgroups to run DOS applications from a shared PC while working on terminals or workstations. On 18 February 1991, several members of the Multiuser DOS Federation issued a press release regarding their intentions to support DPMI (mostly

DPMI 1.0 In computing, the DOS Protected Mode Interface (DPMI) is a specification introduced in 1989 which allows a DOS program to run in protected mode, giving access to many features of the new PC processors of the time not available in real mode. It ...

) in their products including Alloy Computer Products Inc. ( PC-PLUS), Bluebird Systems, Inc. ( SuperDOS),

Concurrent Controls, Inc. Multiuser DOS is a real-time multi-user multi-tasking operating system for IBM PC-compatible microcomputers. An evolution of the older Concurrent CP/M-86, Concurrent DOS and Concurrent DOS 386 operating systems, it was originally developed by ...

( CCI Concurrent DOS 386,

CCI Multiuser DOS Multiuser DOS is a real-time multi-user multi-tasking operating system for IBM PC-compatible microcomputers. An evolution of the older Concurrent CP/M-86, Concurrent DOS and Concurrent DOS 386 operating systems, it was originally developed by ...

), Digital Research, Inc. (

DR Multiuser DOS Multiuser DOS is a real-time multi-user multi-tasking operating system for IBM PC-compatible microcomputers. An evolution of the older Concurrent CP/M-86, Concurrent DOS and Concurrent DOS 386 operating systems, it was originally developed by ...

), S&H Computer Systems, Inc. (

TSX-32 TSX-32 has been a general purpose 32-bit multi-user multitasking operating system for x86 architecture platform, with a command line user interface. It is compatible with some 16-bit DOS applications and supports file systems FAT16 and FAT32. It ...

), StarPath Systems, Inc. ( Vmos/3),

The Software Link The Software Link, Inc. (TSL) was a company in Norcross, Georgia that developed software for personal computers from 1986 to 1994. The company was co-founded by Rod Roark and Gary Robertson. Products * PC-MOS: an MS-DOS-like multiuser operating ...

(

PC-MOS/386 PC-MOS/386 is a multi-user, multitasking computer operating system produced by The Software Link (TSL), announced at COMDEX in November 1986 for February 1987 release. PC-MOS/386, a successor to PC-MOS, can run many MS-DOS programs on the ho ...

), THEOS Software Corporation (

THEOS THEOS, which translates from Greek as "God", is an operating system which started out as OASIS, a microcomputer operating system for small computers that use the Z80 processor. When the operating system was launched for the IBM Personal Comp ...

Intelligent Graphics Corporation VM/386 is a multitasking operating system or 'control program' that took early advantage of the capabilities of Intel's 386 processor. By utilizing Virtual 8086 mode, users were able to run their existing text-based and graphical DOS software i ...

(

VM/386 VM/386 is a multitasking operating system or 'control program' that took early advantage of the capabilities of Intel's 386 processor. By utilizing Virtual 8086 mode, users were able to run their existing text-based and graphical DOS software i ...

). Several of them had previously worked on the alternative

XVCPI In computing, the Virtual Control Program Interface (VCPI) is a specification published in 1989 by Phar Lap Software that allows a DOS program to run in protected mode, granting access to many features of the processor not available in real mode ...

specification.

References

DOS on IBM PC compatibles {{organization-stub

See also

References