Re: my Emacs is broken

[Jan D.]

>     Richard> My Emacs is broken:  It starts an X window, but that is blank and
>     Richard> does not react to any input.  This is in
>     Richard> 
>     Richard> In GNU Emacs ---current CVS--- (sparc-sun-solaris2.8, X toolkit)
>     Richard> 
>     Richard> I guess this problem is related with this change:
>     Richard> 
>     Richard> 2002-08-17  Richard M. Stallman  <address@hidden>
>     Richard> 
>     Richard>  * s/sol2-5.h (BROKEN_SIGIO): Add #undef.
> 
> When I set the DISPLAY variable to 0:0 I get the same result as Markus
> and David Koppelman. If the DISPLAY variable is either set to `X-hostname`:0.0
> (that's what I always use) or localhost:0.0 (as long as we're on the 
> X-server),
> than everything's fine. David Koppelman just sent me email that it also
> works for him when the DISPLAY var is set properly.

I assume you mean :0.0?  If not, that may be some Sun specific thing.
Anyway, if you set DISPLAY to :0.0 you let the Xlib choose "optimal"
communication mechanism to the X server, whatever that may be.
If you use hostname:0 you usually get TCP/IP over the loopback i/f (i.e.
stream sockets).  Setting DISPLAY to unix:0 gives you unix domain sockets,
which usually is a bit faster than TCP/IP (but not much,
just a few percent on my box).

It is possible that :0.0 on your machine selects some means of communication
that does not work with SIGIO.  Could be shared memory perhaps.  Some
types of X over shared memory requires application support.  Emacs does
not have that.

        Jan D.