Editing Multiuser DOS (section)

=={{anchor|MDOS|5.0|5.1}}Multiuser DOS==
<!-- This section may be linked to from inside or outside this article. Do not rename without keeping in sync. -->
{{About|Concurrent DOS|other uses|MDOS (disambiguation)|section=yes}}

Later versions of Concurrent DOS 386 incorporated some of the enhanced functionality of DR's later single-user PC DOS clone [[DR DOS 5.0]], after which the product was given the more explanatory name "Multiuser DOS" (a.k.a. MDOS), starting with version 5.0 (with BDOS 6.5) in 1991.<ref name="Scannell_1991_Tools"/>

Multiuser DOS suffered from several technical limitations that restricted its ability to compete with [[local area network|LANs]] based on [[PC DOS]]. It required its own special [[device driver]]s for much common hardware, as PC DOS drivers were not multiuser or multi-tasking aware. Driver installation was more complex than the simple PC DOS method of copying the files onto the boot disk and modifying [[CONFIG.SYS]] appropriately{{snd}} it was necessary to relink the Multiuser DOS [[Kernel (operating system)|kernel]] (known as a ''nucleus'') using the [[SYSGEN]] command.

Multiuser DOS was also unable to use many common PC DOS additions such as [[network stack]]s, and it was limited in its ability to support later developments in the PC-compatible world, such as [[graphics adaptor]]s, [[sound card]]s, [[CD-ROM]] drives and mice. Although many of these were soon rectified{{snd}} for example, graphical terminals were developed, allowing users to use [[Color Graphics Adapter|CGA]], [[Enhanced Graphics Adapter|EGA]] and [[Video Graphics Array|VGA]] software{{snd}} it was less flexible in this regard than a network of individual PCs, and as the prices of these fell, it became less and less competitive, although it still offered benefits in terms of management and lower total cost of ownership. As a multi-user operating system its price was higher than a single-user system, of course, and it required special device drivers, unlike single-user multitasking DOS add-ons such as [[Quarterdeck Office Systems|Quarterdeck's]] [[DESQview]]. Unlike MP/M, it never became popular for single-user but multitasking use.

When Novell acquired Digital Research in 1991<ref name="Scott_1991"/><ref name="BW_1991"/><ref name="Allchin_1992"/> and abandoned Multiuser DOS in 1992, the three Master VARs DataPac Australasia, Concurrent Controls<ref name="Barney_1994_CCI"/> and Intelligent Micro Software<ref name="Pontin_1995_IMS"/> were allowed to license the source code of the system to take over and continue independent development of their derivations in 1994.

Known versions include:

* DR Multiuser DOS 5.00 (1991),<ref name="CW_1991_DRMDOS50"/> 5.01
* Novell DR Multiuser DOS 5.10 (1992-04-13),<ref name="CW_MDOS51"/> 5.11<ref name="CCI_FPROD"/>
* Novell DR Multiuser DOS 5.13 (BDOS 6.6<!-- 1466 -->, 1992)

All versions of Digital Research and Novell DR Multiuser DOS reported themselves as "IBM PC DOS" version 3.31.

===Adaptations===
===={{anchor|Datapac|System Manager}}DataPac Australasia====
<!-- This section may be linked to from inside or outside this article. Do not rename without keeping in sync. -->

Known versions by DataPac Australasia Pty Limited include:

* Datapac Multiuser DOS 5.0
* Datapac Multiuser DOS 5.1 (BDOS 6.6)
<!-- * Datapac System Manager 5.0? did it exist? -->
* Datapac System Manager 7.0 (1996-08-22)

<!-- System Manager found market acceptance as NetWare dial-in WAN servers and as multiuser servers for cheaper terminals in China. -->
In 1997, Datapac was bought by [[Citrix Systems, Inc.]],<ref name="Citrix_1997"/><ref name="Duursma_2006_Citrix"/><ref name="Costello_1997_DataPac"/> and System Manager was abandoned soon after. In 2002 the Sydney-based unit was spun out into Citrix' Advanced Products Group.<ref name="Mulcaster_2002"/>

===={{anchor|CCI|CCI7.00|CCI7.10|CCI7.21|CCI7.22}}Concurrent Controls====
<!-- This section may be linked to from inside or outside this article. Do not rename without keeping in sync. -->

Known CCI Multiuser DOS versions by Concurrent Controls, Inc. (CCI) include:

* CCI Multiuser DOS 7.00
* CCI Multiuser DOS 7.10
* CCI Multiuser DOS 7.21<ref name="CCI_1997_HELP"/>
* CCI Multiuser DOS 7.22<ref name="CCI_1997_HELP"/> R1 (September 1996), R2 (1996), R3 (1997), R4 GOLD/PLUS/LITE (BDOS 6.6<!-- 1466h -->, 1997-02-10), R5 GOLD (1997), R6 GOLD (1997), R7 GOLD (June 1998), R8 GOLD, R9 GOLD, R10 GOLD, R11 GOLD (2000-09-25), R12 GOLD (2002-05-15), R13 GOLD (2002-07-15), R14 GOLD (2002-09-13), R15 GOLD, R16 GOLD (2003-10-10), R17 GOLD (2004-02-09), R18 GOLD (2005-04-21)<!-- 2004? -->

All versions of CCI Multiuser DOS report themselves as "IBM PC DOS" version 3.31.<ref name="CCI_1997_HELP"/> Similar to [[SETVER]] under [[DOS]], this can be changed using the Multiuser DOS {{mono|DOSVER&nbsp;x.y}} utility.<ref name="CCI_1997_HELP"/>

In 1999, CCI changed its name to Applica, Inc.<ref name="CCI_1999_Applica"/> In 2002 Applica Technology became Aplycon Technologies, Inc.<ref name="Aplycon_2002_Applica"/>

===={{anchor|IMS}}Intelligent Micro Software, Itera and Integrated Solutions====

=====DOS 386 Professional=====
{{Expand section|date=January 2017}}

====={{anchor|IMS5.1|IMS5.11|IMS5.14|IMS7.0|IMS7.1}}IMS Multiuser DOS=====
Known adaptations of IMS Multiuser DOS include:

* IMS Multiuser DOS Enhanced Release 5.1 (1992)
* IMS Multiuser DOS 5.11
* IMS Multiuser DOS 5.14
* IMS Multiuser DOS 7.0
* IMS Multiuser DOS 7.1 (BDOS 6.7<!-- 1467h -->, 1994)

All versions of IMS Multiuser DOS report themselves as "IBM PC DOS" version 3.31.

====={{anchor|7.50|7.51|7.52|7.53|7.54|7.60|7.61|7.62|7.63|7.70|7.71|7.72|7.73|7.74|7.80|7.81|7.82|7.83|7.90|7.91|7.92|7.93|7.94|7.95}}REAL/32=====
<!-- This section may be linked to from inside or outside this article. Do not rename without keeping in sync. -->
[[File:IMS REAL-32 Version 7.6 720x400.png|thumb|IMS REAL/32 Version 7.6]]
Intelligent Micro Software Ltd. (IMS) of [[Thatcham]], UK, acquired a license to further develop Multiuser DOS from Novell in 1994 and renamed their product REAL/32 in 1995.<ref name="Pontin_1995_IMS"/>

Similar to [[FlexOS]]/[[4690 Operating System|4690 OS]] before, IBM in 1995 licensed REAL/32 7.50 to bundle it with their 4695 POS terminals.<ref name="Pontin_1995_IMS"/>{{clarify|date=September 2018|reason=Not clear if this replaces FlexOS 386 on these systems, or if merely upgrades some parts of FlexOS from REAL/32.}}

IMS REAL/32 versions:

* IMS REAL/32 7.50 (BDOS 6.8<!-- 1468h -->, 1995-07-01), 7.51 (BDOS 6.8<!-- 1468h -->), 7.52 (BDOS 6.9<!-- 1469h -->), 7.53 (BDOS 6.9<!-- 1469h -->, 1996-04-01), 7.54 (BDOS 6.9<!-- 1469h -->, 1996-08-01)<ref name="RM_1996_754"/>
* IMS REAL/32 7.60 (BDOS 6.9<!-- 1469h -->, February 1997),<ref name="MaxFrame_2001_760"/> 7.61, 7.62, 7.63
* IMS REAL/32 7.70 (November 1997), 7.71, 7.72, 7.73, 7.74 (1998)<ref name="MaxFrame_2001_774"/>
* IMS REAL/32 7.80, 7.81 (February 1999), 7.82, 7.83 (BDOS 6.10<!-- 146Ah -->)
* IMS REAL/32 7.90 (1999)<!-- before August 1999 -->,<ref name="IMS_1999_R32-790"/> 7.91, 7.92
* ITERA IMS REAL/32 7.93 (June 2002<!-- or November 2002 -->),<ref name="IMS_2002_R32-793"/> 7.94 (BDOS 6.13<!-- 146Dh -->, 2003-01-31)<ref name="IMS_2003_R32-794"/>
* Integrated Solutions IMS REAL/32 7.95<!-- (August 2010 or earlier) --><ref name="IS_2010_R795"/>

REAL/32 7.50 to 7.74 report themselves as "IBM PC DOS" version 3.31, whereas 7.80 and higher report a version of 6.20.<!-- this holds true at least up to 7.94, not sure about 7.95 --> [[Logical Block Addressing|LBA]] and [[FAT32]] support was added with REAL/32 7.90 in 1999.<ref name="IMS_1999_R32-790"/> On 19 April 2002, Intelligent Micro Software Ltd. filed for insolvency and was taken over by one of its major customers, Barry<!-- Stuart --> Quittenton's Itera Ltd.<ref name="LII_2002_Discontinued"/><ref name="LII_2002_NewOwner"/><ref name="LII_2002_ITERA"/> This company was dissolved on 2006-03-28.<ref name="ITERA_UK"/><ref name="NEXOK_Itera"/> As of 2010 REAL/32 was supplied by Integrated Solutions<!-- Ltd. --> of Thatcham, UK, but the company, at the same address, was later listed as builders.<ref name="IS_2010_R795"/>

=====REAL/NG=====
<!-- This section may be linked to from inside or outside this article. Do not rename without keeping in sync. -->
REAL/NG was <!-- ITERA? -->IMS' attempt to create the "Next Generation" of REAL/32, also named "REAL/32 for the internet age". REAL/NG promised "increased range of hardware from PCs to x86 multi-processor server systems".<ref name="realng"/>

Advertised feature list, as of 2003:<ref name="keyfeaturesofrealng"/>

* Runs with [[Red Hat Linux|Red Hat 7.3]] or later version of [[Linux]]
* [[Backward compatible]] with DOS and REAL/32
* Max 65535 [[virtual console]]s; each of these can be a user
* No Linux expertise required
* Administration/setup/upgrade by web browser (local and remote)
* Supplied with [[TCP/IP]] Linux-/Windows-based terminal emulator for the number of users purchased
* Print and file sharing built in
* [[Drive mapping]] between Linux and REAL/NG servers built in
* User hardware support
* Increased performance
* Vastly increased TPA
* [[Multi-processor]] support
* Improved hardware support
* Built-in firewall support
* Very low cost per seat
* Low total cost of ownership
* Supplied on CD
* Supplied with a set of Red Hat CDs

By 10 December 2003, IMS made "REALNG V1.60-V1.19-V1.12" available,<ref name="realng_probablylatest"/> which, based on the [[Internet Archive]], seems to be the latest release.

By 2005, the realng.com website was mirroring the IMS main website, and had no mention of REAL/NG, only REAL/32.<ref name="realng_disappear"/>