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The pages on this site contain documentation for very old MS-DOS software, purely for historical purposes. If you're looking for up-to-date documentation, particularly for programming, you should not rely on the information found here, as it will be woefully out of date.

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     Command: Windows Kill Application (WKA)
 
     Syntax:  WKA
 
     Summary: Simulates a fatal error in the current task.
 
     Description:
 
     There may be times when you want to halt your program immediately.
     You can force an immediate interrupt of a CVW session by pressing
     CTRL+ALT+SYSREQ. You then have the opportunity to change debugging
     options, such as setting breakpoints and modifying variables. To
     resume continuous execution, press F5; to single-step, press F10.
 
     You should take care when you interrupt the CVW session. For
     example, if you interrupted the session while Windows code or
     other system code was executing, attempting to use the Step or
     Trace functions will produce unpredictable results. When you
     interrupt the CVW session, it is usually safest to set breakpoints
     in your code and then resume continuous execution, rather than
     using Step or Trace.
 
     An infinite loop in your code presents a special problem. Again,
     since you should avoid using Step or Trace after interrupting your
     program, you should try to locate the loop by setting breakpoints
     in places you suspect are in the loop.
 
     Terminating Your Application with WKA
 
     At times, you may have to terminate the application. The WKA
     command terminates the currently executing task. Since this task
     is not necessarily your application, you should use the WKA
     command only when your application is the currently executing
     task.
 
     If your application is the currently executing task and is
     executing a module containing CodeView information, the Source
     window highlights the current line or instruction. However, if
     your application contains modules that are compiled without
     CodeView information, it is more difficult to determine whether
     the assembly-language code displayed in the Source window belongs
     to your application or to another task.
 
     In this case, use the Windows Display Global Heap (WDG) command,
     with the value in the CS register as the argument. CVW displays a
     listing that indicates whether the code segment belongs to your
     application.
 
     If the current code is in your application, you can safely use the
     WKA command without affecting other tasks. However, the WKA
     command does not perform all the cleanup tasks associated with the
     normal termination of a Windows application.
 
     For example, GDI objects created during the execution of the
     program but not destroyed before you terminated the program remain
     allocated in the global heap. This reduces the amount of memory
     available during the rest of the Windows session. Because of this,
     you should use the WKA command to terminate the application only
     if you cannot terminate it normally.
 
     NOTE: The WKA command simulates a fatal error in your application,
           causing Windows to display an Unexpected Application Error
           message box. After you close this message box, Windows may
           not release subsequent mouse input messages from the system
           queue until you press a key.
 
           If this happens, the mouse pointer moves on the Windows
           screen but Windows does not respond to the mouse. After you
           press any key, Windows responds to the queued mouse events.
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