How to intercept messages about reboot or logoff?

Question

I tried to find information on this, but only found the WM_QUERYENDSESSION function. How can I use this to intercept reboot / shutdown messages?

import win32gui, win32con

msg = win32gui.GetMessage(None, 0, 0)
if msg and msg.message == win32con.WM_QUERYENDSESSION:
    print('EXIT')

Here is an example of my code, but when I run it it doesn't handle any actions. and does not intercept shutdown messages

This is straight from the [documentation](https://learn.microsoft.com/en-us/windows/win32/shutdown/wm-queryendsession): *"A window receives this message through its `WindowProc` function."* Why did you avoid reading it? — IInspectable, Jul 18 '20 at 12:36

score 0 · Answer 1 · answered Jul 20 '20 at 02:56

According to WM_QUERYENDSESSION: The WM_QUERYENDSESSION message is sent when the user chooses to end the session or when an application calls one of the system shutdown functions. A window receives this message through its WindowProc function.

So this message will only take effect when sent by the application and accepted in the WindowProc function.

How to intercept messages about reboot or logoff?

1 Answers1