Q73668: MS-DOS-Based Application Characteristics Under Windows

Article: Q73668
Product(s): Microsoft Windows Software Development Kit
Version(s): WINDOWS:3.0,3.1
Operating System(s): 
Keyword(s): kb16bitonly
Last Modified: 05-NOV-1999

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The information in this article applies to:

- Microsoft Windows Software Development Kit (SDK) versions 3.0, 3.1 
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SUMMARY
=======

This article discusses the mechanism that the Microsoft Windows graphical
environment uses to run an MS-DOS (non-Windows) application.

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

In the Window environment, each MS-DOS-based application runs has a
Windows-based application to act as its agent. When the MS-DOS-based application
is running in a window under enhanced mode Windows, and the MS- DOS-based
application makes a call to the display hardware, the agent intercepts the call
and places the character into its window. To the MS-DOS-based application, the
agent acts as a virtual copy of the display hardware.

NOTE: The Windows agent does not manage the display; it simply renders the
MS-DOS-based application's display into a window.

To determine if an application is an MS-DOS-based application, check the
application's name to see if it matches the name of the MS-DOS-based application
agent. The module name of the MS-DOS-based application agent is WINOLDAP. The
following code fragment performs this check:

     BOOL IsThisWOAWindow(HWND hWnd)
     {
        BOOL IsWOA;
        HANDLE hModWOA;
        IsWOA = FALSE;
        if (hModWOA = GetModuleHandle("WINOLDAP"))
           {
           if (hModWOA == (HANDLE)(GetClassWord(hWnd, GCW_HMODULE)))
              {
              IsWOA = TRUE;
              }
           }
        return IsWOA;
     }

To determine how many MS-DOS-based applications are running at any given time,
call the code above from an loop that enumerates the handles of all windows in
the system.

Additional query words: 3.00 3.10

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Keywords          : kb16bitonly 
Technology        : kbAudDeveloper kbWin3xSearch kbSDKSearch kbWinSDKSearch kbWinSDK300 kbWinSDK310
Version           : WINDOWS:3.0,3.1

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