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 in safely separate environments. The system offered a high degree of control, with the ability to set memory and CPU usage limits. Unique CONFIG.SYS and AUTOEXEC.BAT files could be configured for each application, and even different DOS versions.
VM/386 had initially been developed by Softguard Systems, a producer of copy-protection software, with plans to include features like non-DOS system support, but financial constraints forced its sale to Intelligent Graphics Corporation, which launched the product in 1987. It won a PC Magazine award for technical excellence in 1988. The company also introduced a multi-user version, which allowed a number of serial terminals and even graphical systems to be connected to a single 386 computer. Current versions of the software have built on the multi-user support, and can handle tens of users in a networked environment with Windows 3.11 support, access controls, virtual memory and device sharing, among other features.
A version of the software designed to cooperate with Unix was bundled with Everex Systems workstations. The system now sees use mainly in vertical applications like point-of-sale systems, where its ability to run reliably on cheap, reliable hardware outweigh any gains from newer operating systems that are more complex and less reliable.
Early competition included Desqview 386, Sunny Hill Software's Omniview, and Windows/386 2.1. As the target market shifted away from single-user systems to multiple-user setups with many serial terminals it began to compete more directly with the likes of Multiuser DOS and PC-MOS/386.
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- Michael J. Miller, Tracey Capen (13 February 1989), "Multitasking", InfoWorld: 57–58
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- "The 5th Annual Awards (1988): 386 Software Technology", PC Magazine
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- Everex Systems Inc. announces DOS multitasker for UNIX workstations., 23 October 1989