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Q81493: Using VCPI Programs with Windows

Article: Q81493
Product(s): Microsoft Windows 95.x Retail Product
Version(s): WINDOWS:3.0,3.0a,3.1,3.11
Operating System(s): 
Keyword(s): 
Last Modified: 05-OCT-1999

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The information in this article applies to:

- Microsoft Windows versions 3.0, 3.0a, 3.1, 3.11 
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SUMMARY
=======

Many MS-DOS-based applications use the Virtual Control Program Interface (VCPI)
specification to directly access protected-mode extended memory on an 80386 or
80486 computer. These programs do not work with Microsoft Windows version 3.0 in
386 enhanced mode. They work in Windows in real mode and may work in standard
mode. Windows uses a newer standard called DOS Protected Mode Interface (DPMI).

DPMI is a multitasking version of VCPI with a few other enhancements. Many
software companies have already announced plans to support DPMI in future
releases of their products. If you experience difficulties running an MS-
DOS-based application in standard or enhanced mode of Windows, check with the
MS-DOS-based-application manufacturer to see if it now supports the DPMI
specification.

MORE INFORMATION
================

The following switch can be entered into the SYSTEM.INI file in the [386Enh]
section to turn off the warning message that appears when an MS-DOS-based
application attempts to use VCPI:

  VCPIWarning=false

NOTE: Changing this switch does not allow the application to run. It merely
suppresses the warning message if you attempt to run one of these applications.

The following is a partial list of applications that use the VCPI specification
to access extended memory:

  Application                          Vendor
  --------------------------------------------------------------------
  Lotus 1-2-3 release 3.0              Lotus
  Interleaf Publisher                  IBM
  Autocad 386                          Autodesk
  Paradox 386                          Borland
  FoxBase+ 386                         Microsoft
  Smalltalk 80 386                     ParcPlace
  Common Lisp CLOE-386                 Symbolics
  Laboratory Microsystems UR/Forth     STSC
  APL Plus II                          STSC
  VM/386                               Intelligent Graphics Corporation
  Concurrent DOS 386                   Digital Research
  PC-MOS/386                           The Software Link

Lotus has announced that version 3.1 will follow the DPMI specifications and will
run under all three modes of Windows 3.0.

PC-MOS is a multitasking operating environment similar to Windows/386. You cannot
run Windows under PC-MOS because Microsoft Windows/286, Windows/386, and Windows
3.0 and 3.1 are all protected-mode software competing for the same resources.

The following is a list of 386 memory managers that use the VCPI specification
and are incompatible with Windows 3.0 running in enhanced mode:

  Memory Manager                       Vendor
  --------------------------------------------------------------------
  ILIM386.SYS                          Intel
  Soft Bits 386                        Soft Bits
  CEMM                                 COMPAQ Computer Company
  QEMM                                 Quarterdeck Office Systems
  386-to-the-Max                       Qualitas

Most of the companies listed above are also planning versions of their
applications that will use the DPMI specification.

Additional query words: 3.00 3.0 3.0a 3.00a VCPI DPMI 3.10 3.1 winmem win31 3.11

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Keywords          :  
Technology        : kbWin3xSearch kbZNotKeyword3 kbWin300 kbWin300a kbWin310 kbWin311
Version           : WINDOWS:3.0,3.0a,3.1,3.11

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