patch to make emacs proceed if DISPLAY is unreachable

[Vivek Dasmohapatra]

Hi: In the past, I've had to administer various machines with NFS mounted 
homedirs, and from time to time when su'ing I've been bitten by the fact
that altough DISPLAY was set, emacs couldn't read my .Xauthority
file (as it was on NHS). I've had a look at the code, and figure oud what's
going on, (I think), and put together this patch to make emacs proceed
as if -nw had been supplied if DISPLAY is unreachable for some reason.

This behaviour does not apply to displays explicitly provided by -d
on the command line, only to implicit DISPLAY settings.

I find I prefer this behaviour, so I'm submitting the patch,
hopefully the emacs team will consider either using this patch
or implementing similar behaviour themselves (I think the patch
is without side effect, but I could be wrong).

--
Vivek

emacs.display-lenience.patch
Description: Text document