Windows NT VDMs Keep Their Own System Time

 Last reviewed: May 8, 1997
Article ID: Q102611

The information in this article applies to:
  • Microsoft Windows NT operating system version 3.1
  • Microsoft Windows NT Advanced Server version 3.1

SUMMARY

Windows NT virtual DOS machines (VDMs) keep their own system time. Each time an MS-DOS-based application or a 16-bit Windows-based application is started, its BiosDataArea tick count is initialized to the current system time. When an MS-DOS-based application sets the time in a VDM, it is reflected in that VDM only. When a 16-bit Windows-based application changes the time, the new time is reflected in all 16-bit Windows-based applications running in Windows on Windows (WOW).

MORE INFORMATION

Windows NT is designed this way because MS-DOS-based applications depend on timer tic hardware for their sense of time. Many MS-DOS-based applications do not interact favorably with the timer tic hardware.

Additional query words: prodnt
Keywords : kbother nt16ap ntdosap ntgeneral
Version : 3.1
Platform : WINDOWS

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Last reviewed: May 8, 1997
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