DOCUMENT:Q73668  05-NOV-1999  [win16sdk]
TITLE   :MS-DOS-Based Application Characteristics Under Windows
PRODUCT :Microsoft Windows Software Development Kit
PROD/VER:WINDOWS:3.0,3.1
OPER/SYS:
KEYWORDS:kb16bitonly

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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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