Prevent Windows 7 Shutdown

Question

I know that shutdown -a will abort a Windows shutdown, but I need to know if there is anything any where I can check for to see if a shutdown is in progress.

Ideally, I'd like a small program like this:

 import os

 while True:
    shuttingDown = <shutdown variable to check>
    if shuttingDown:
         os.system("shutdown.exe -a")

Answer 1

For preventing a Windows shutdown when it is happening, you can react to the WM_QUERYENDSESSION message (don't know if you can do that easily with Python's win32 API but it's simple in C). This might not prevent applications from closing because Windows sends WM_ENDSESSION to those that answer TRUE to the query message.

I guess you rather want to prevent a timed shutdown using "shutdown.exe". I'm sure that program uses InitiateSystemShutdown to show the shutdown dialog, but there are no resources on intercepting that call (at least I didn't find any or know of a Windows feature that allows such a thing).