Q80124: Retrieving the Names of Simultaneous Tasks Under Windows

Article: Q80124
Product(s): Microsoft Windows Software Development Kit
Version(s): WINDOWS:3.0,3.1
Operating System(s): 
Keyword(s): kb16bitonly
Last Modified: 06-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
=======

There are situations when it is necessary for an application to obtain a list of
all applications that are running in the Windows environment at a particular
time.

In Windows 3.0, instead of using the EnumWindows() function and an
application-supplied callback function to enumerate all parent windows, the
application can retrieve a handle to the first window in the task list and walk
through the list to obtain the names of all windows in the task list.

In Windows 3.1, however, an application should instead use the ToolHelp Library
functions. More specifically, use TaskFirst(), TaskNext(), ModuleFirst(), and
ModuleNext().

NOTE: Since the ToolHelp functions work in Windows 3.0 and since ToolHelp is
itself a redistributable library, these functions can be safely used in Windows
3.0 also.

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

The most efficient way to retrieve the name of each task running under Windows
3.0 is to use the GetWindow() function. GetWindow (hwnd, GW_HWNDFIRST) provides
the handle to the first window in the task list. The application can walk
through the task list by calling GetWindow (hwndCurrent, GW_HWNDNEXT). The
following example demonstrates how to obtain a handle to each top-level window.
The GetWindowText() function provides the name of each window from its handle.

      hwndNext = GetWindow(hWnd, GW_HWNDFIRST);
      /* Where: hWnd is the original/current window. GW_HWNDFIRST will
         return the first sibling window for a child window, otherwise
         it returns the first top-level window in the system's list of
         top-level windows */ 
      while (hwndNext)
      {
         if ((hwndNext != hWnd) &&  // Do not get this application's
                                    // name.
             (IsWindowVisible(hwndNext)) &&
             (!GetWindow(hwndNext, GW_OWNER)))
         {
            if (GetWindowText(hwndNext, (LPSTR)szTemp, sizeof(szTemp)))
            {
              // This is a valid top-level window handle.
              // Its name is in szTemp...
            }
         }
         hwndNext = GetWindow(hwndNext, GW_HWNDNEXT);
      }

The code above will retrieve the name of each visible window. To also retrieve
the names of invisible windows, remove the call to IsWindowVisible().

Additional query words: no32bit 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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