DESQview (DV) is a text mode multitasking operating environment developed by Quarterdeck Office Systems which enjoyed modest popularity in the late 1980s and early 1990s. Running on top of DOS, it allows users to run multiple programs concurrently in multiple windows.

Desq

Quarterdeck's predecessor to DESQview was a task switching product called Desq (shipped late April allows multiple copies of the same single-tasking BBS software to run simultaneously on a single computer, resulting in a multi-user BBS.

Decline of DESQview

DESQview does not provide a graphical user interface (GUI). While Quarterdeck did provide suites of programming libraries and utilities to support the development of software to use its features, these never became widely popular. DESQview's ability to run most software with no modification and the cost of "run-time" licenses, combined with the costs of the development suites themselves made this an unreasonable combination for commercial shrink-wrapped software publishers and vendors.

Microsoft released Windows 3.0 with its own memory management and multitasking features. While DESQview was far faster, smaller, and more stable, it was more expensive and didn't include support for the graphical features of MS Windows.

The decline of QEMM started with the bundling of a memory manager in Digital Research's DR DOS 5.0, released in 1990. To catch on, Microsoft included its own EMM386 in MS-DOS 5.0, while previously the memory management functionality was only available with Windows. QEMM could still be used instead, notably with Windows 3.1x, but only for incremental benefit. Sales of QEMM declined. In August 1994, after three quarters of losses, the company laid off 25% of their employees and the CEO, president, and founder Terry Myers resigned.

As users moved from DESQview to other platforms, notably Windows 3.x and OS/2, third party utility authors wrote utility programs that emulated some DESQview API functions to allow suitably equipped DOS programs to co-operate with these OS. The most notable are TAME (for Windows) and OS/2SPEED (for OS/2).

DESQview/X

Quarterdeck eventually also released a product named DESQview/X (DVX), which is an X Window System server running under DOS and DESQview and thus provides a GUI to which X software (mostly Unix) could be ported.

DESQview/X had three window managers that it launched with, X/Motif, OPEN LOOK, and twm. The default package contained only twm, the others were costly optional extras, as was the ability to interact on TCP/IP networks. and preferable to OS/2 on 286. The magazine that year listed version 3.0 as among the "Distinction" winners of the BYTE Awards, stating that "unlike OS/2, DESQview lets you run the programs you've already paid for ... Many users will find that DESQview is all they need".

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Further reading

  • Screenshots of DESQview/X
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