Re: Reading D-Bus messages

[Ken Brown]

[For the moment I'm leaving out the cygwin list, because I think I see 
the problem.]

On 9/23/2010 3:19 AM, Michael Albinus wrote:
> Ken Brown<address@hidden>  writes:
>
> > Hi Michael,
>
> Hi Ken,
>
> > > I do not understand all details of keyboard.c. Is there something I need
> > > to set in order to urge the call of xd_read_queued_messages (via
> > > gobble_input)? Or do I need to suppress further polling? What is the
> > > difference for Emacs running with cygwin, compared with the GNU/Linux case?
> > >
> > > Btw, when I call xd_read_queued_messages inside xd_pending_messages,
> > > everything works fine also with cygwin. But I guess this isn't the
> > > correct solution.
> >
> > I don't know enough to attempt an answer.  Is there any chance you
> > could write a small self-contained program that exhibits the problem?
> > If so, there's a chance someone on the Cygwin list could help.
>
> The problem seems to be how gobble_input is called in kbd_buffer_get_event
> (keyboard.c):
>
> /* Note SIGIO has been undef'd if FIONREAD is missing.  */
> #ifdef SIGIO
>        gobble_input (0);
> #endif /* SIGIO */
>
> SIGIO is undefined, and gobble_input is not called under cygwin
> therefore. If I remove this conditional directive, D-Bus connections in
> Emacs work fine! What is the reason, that SIGIO is undefined under cygwin?

Grepping /usr/include, I see that SIGIO (and FIONREAD) seem to be 
defined.  So I think the trouble must be that these get undefined in the 
emacs build, perhaps because of the '#undef INTERRUPT_INPUT' in 
src/s/cygwin.h.  I changed it to '#define INTERRUPT_INPUT' and rebuilt, 
but dbus still didn't work.  I'm in the process of bootstrapping right 
now so I can try again.  I don't understand the build process well 
enough to know whether bootstrapping should be necessary after this change.

Ken