Re: Exit hooks not run at logout on w32

[Jason Rumney <jasonr@gnu.org>]

Mathias Dahl wrote:
>     Applications with a window and message queue receive shutdown
>     notifications through the WM_QUERYENDSESSION message. These
>     applications should perform any required cleanup while processing
>     this message and return TRUE to indicate that they can be
>     terminated. 
>   

> So, I conclude that displaying a dialog box ("Do you want to save bla
> bla?") would violate the "rules" above, wouldn't they?
>   

That was my same conclusion, based on reading the documentation of the 
actual system messages. But it is interesting that the advice above 
contradicts the advice in the documentation for WM_QUERYENDSESSION, 
which says you should NOT perform cleanup while processing that message, 
but save it for WM_ENDSESSION. I think the contradictions in Microsoft's 
documentation about shutdown are what is causing the confusion here. 
Lennart posted another contradiction, where in the documentation for 
InitiateSystemShutdown, there is advice that applications can delay 
shutdown if they have unsaved data if a particular flag is passed. But 
that advice is for users of InitiateSystemShutdown, not for recipients 
of the shutdown messages, so my opinion is that it is informing of worst 
case expectations for code that wants to shut the system down (assuming 
that not all applications will take the advice elsewhere - apparently 
some of Microsoft's own products do not).