How to gracefully terminate a process?

Question

I want to terminate a number of processes, but I want to give each process the chance to save its data, ask the user about saving a file and even ignore the close request.

Answer 1

Use the EndTask API function. It is the same function that is used by task manager.

BOOL EndTask(      
    HWND hWnd,
    BOOL fShutDown,
    BOOL fForce
);

http://msdn.microsoft.com/en-us/library/ms633492(VS.85).aspx

Answer 2

You can use taskkill /im your_program.exe to send a termination signal to the application. It will trigger a WM_CLOSE to windows message queue. You can use Either https://msdn.microsoft.com/en-us/library/windows/desktop/ms633573(v=vs.85).aspx or

https://docs.microsoft.com/en-us/windows/desktop/api/winuser/nf-winuser-getmessage

to process the message.

Please refer a similar answer Win32 API analog of sending/catching SIGTERM

Answer 3

To add to Chris Becke answer about terminating gracefully terminating console process.

AttachConsole() to attach to the console application and send control break event, similar to that of pressing CTRL+C in command prompt.

Using GenerateConsoleCtrlEvent(CTRL_BREAK_EVENT,processID).

This control event should be handled in console application for graceful termination.

Answer 4

See MSKB Q178893 How To Terminate an Application "Cleanly" in Win32. Basically send send WM_CLOSE to all windows of the target app to allow a grace shutdown, before force kill the app with TerminateProcess

Answer 5

I'm not too sure about the win32 apis but you could shell execute the taskkill command line function.

taskkill /?
taskkill /pid 1230
taskkill /im notepad.exe

The /f switch would force the kill but not using it just sends the termination signal so the application closes gracefully.

Answer 6

EnumWindows enumerates all the top level windows in a process. GetWindowThreadProcessId gets the process and Id of each thread.

You now have enough information to gracefully close any GUI application.

You can send WM_CLOSE messages to any window you wish to close. Many windows handle WM_CLOSE to prompt the user to save documents.You can send a WM_QUIT message using PostThreadMessage to the discovered threads to cause the message loop to terminate.

User code is not allowed to call DestroyWindow from a different app or thread to the windows... if the app does not respond to WM_CLOSE or WM_QUIT requests you're back in TerminateProcess land.

This will not close console applications as the application process, and process that owns the window, are different.

---

Refer to T.s. Arun's answer below for the correct method for dealing with console applications.