Newsgroups: gnu.emacs.bug
Path: utzoo!utgpu!jarvis.csri.toronto.edu!snow.white.toronto.edu!cks
From: cks@white.toronto.edu (Chris Siebenmann)
Subject: Re: X11 hanging behavior with uvaxes, 18.51
Message-ID: <89Feb13.161804est.15497@snow.white.toronto.edu>
Reply-To: cks@white.toronto.edu (Chris Siebenmann)
Organization: Ziebmef home away from home
References: <27941@ucbvax.BERKELEY.EDU> <GRUNWALD.89Feb8112253@flute.cs.uiuc.edu>
Distribution: gnu
Date: Mon, 13 Feb 89 16:17:54 EST

In article <GRUNWALD.89Feb8112253@flute.cs.uiuc.edu> grunwald@flute.cs.uiuc.edu (Dirk Grunwald) writes:
[problem with Emacs 18.51 and X11, where Emacs comes up and just sits there.]
>I've noticed this too -- but in emacs 18.52. I noticed that if you set
>display to the internet name instead of the local name, it works.

 This is apparently a problem with SIGIO on Unix domain sockets in
Ultrix. You can cure the problem by remaking Emacs using s-bsd4-3.h
instead of s-bsd4-2.h.

 Enclosed below is a message I got the last time I mentioned this
problem (and the solution) on this list, which explains exactly what's
going on.

# From: John.Myers@K.GP.CS.CMU.EDU
# To: cks%white.toronto.edu@RELAY.CS.NET
# Subject: Re: 18.52 and X11
# Date: Thu, 27 Oct 88 11:46:00 EDT
#
# Under Ultrix, SIGIO doesn't work on unix domain sockets.--it's never
# delivered.
#
# Emacs isn't hanging, it's spin-looping.  After doing a select, it
# notices that there is input available on stdin, so it calls a routine
# to read and interpret the input.  The routine that gets called to read
# the input notices that it is being run in INTERRUPT_INPUT mode, so
# assumes the input has already been read by the SIGIO handler.  It
# finds nothing in the input buffer (since the SIGIO handler never got
# called), so it returns and emacs goes back to doing a select().
# Repeat.
#
# The X support forces INTERRUPT_INPUT mode so that ^G will work as
# advertised.
#
# Ultrix sucks.
#
# --
# _.John G. Myers	Internet: John.Myers@cs.cmu.edu
#			LoseNet:
# ...!seismo!inhp4!wiscvm.wisc.edu!give!up
# "The world is full of bozos.  Some of them even have PhD's in Computer
# Science"

-- 
	"I shall clasp my hands together and bow to the corners of the world."
			Number Ten Ox, "Bridge of Birds"
Chris Siebenmann		...!utgpu!{ncrcan,ontmoh!moore}!ziebmef!cks
cks@white.toronto.edu	     or ...!utgpu!{,csri!}cks