Re: Getting a hourglass cursor

[Jason Rumney]

Lennart Borgman wrote:
> On Tue, Sep 15, 2009 at 2:15 PM, Jason Rumney <address@hidden> wrote:
>   
> > Eli Zaretskii wrote:
> >     
> > > The case in point is "C-h H", which (at least on Windows) takes an
> > > annoyingly long time.
> > >
> > >       
> > On Windows, we don't support asynchronous timers, so the hourglass will only
> > display if we spend a long time executing lisp code. C-h H is spending time
> > doing redisplay (specifically finding fonts to display the various scripts),
> > so the hourglass does not display.
> >     
>
>
> Are there any difficulties with supporting async timers on w32?
>   

Yes, since Windows does not support signal handlers, anything 
asynchronous needs to be done in another thread, which cannot run Lisp 
code (at least until someone implements multithreading of Lisp, without 
restrictions like one thread per buffer or some of the other 
simplifications that have been talked about).