From owner-freebsd-stable@FreeBSD.ORG  Thu Aug  7 05:30:31 2003
Return-Path: <owner-freebsd-stable@FreeBSD.ORG>
Delivered-To: freebsd-stable@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 7DD1A37B401
	for <freebsd-stable@freebsd.org>;
	Thu,  7 Aug 2003 05:30:31 -0700 (PDT)
Received: from smtp3.adl2.internode.on.net (smtp3.adl2.internode.on.net
	[203.16.214.245])
	by mx1.FreeBSD.org (Postfix) with ESMTP id 4DF3F43F75
	for <freebsd-stable@freebsd.org>;
	Thu,  7 Aug 2003 05:30:30 -0700 (PDT)
	(envelope-from smckay@internode.on.net)
Received: from smtp3.adl2.internode.on.net (localhost [127.0.0.1])
	h77CUPYV049748	for <freebsd-stable@freebsd.org>;
	Thu, 7 Aug 2003 22:00:26 +0930 (CST)
Received: (from mailnull@localhost)h77CUPXf049744
	for <freebsd-stable@freebsd.org>;
	Thu, 7 Aug 2003 22:00:25 +0930 (CST)
X-Authentication-Warning: smtp3.adl2.internode.on.net: mailnull set sender to
	<smckay@internode.on.net> using -f
Received: from dungeon.home (ppp188-209.lns1.bne1.internode.on.net
	[150.101.188.209])
	by localhost (8.12.9/8.12.9+MIMEDefang) with ESMTP id h77CUOYV049739;
	Thu, 07 Aug 2003 22:00:25 +0930
Received: from dungeon.home (localhost [127.0.0.1])
	by dungeon.home (8.12.8p1/8.11.6) with ESMTP id h77CUMgj003099;
	Thu, 7 Aug 2003 22:30:23 +1000 (EST)
	(envelope-from mckay)
Message-Id: <200308071230.h77CUMgj003099@dungeon.home>
To: freebsd-stable@freebsd.org
Date: Thu, 07 Aug 2003 22:30:22 +1000
From: Stephen McKay <smckay@internode.on.net>
X-Streamed-Recipients: <freebsd-stable@freebsd.org>
X-Proc-As: freebsd-stable
X-Scanned-By: MIMEDefang 2.33 (www . roaringpenguin . com / mimedefang)
cc: Stephen McKay <smckay@internode.on.net>
Subject: nvi dying with "Resource temporarily unavailable"
X-BeenThere: freebsd-stable@freebsd.org
X-Mailman-Version: 2.1.1
Precedence: list
List-Id: Production branch of FreeBSD source code
	<freebsd-stable.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-stable>,
	<mailto:freebsd-stable-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-stable>
List-Post: <mailto:freebsd-stable@freebsd.org>
List-Help: <mailto:freebsd-stable-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-stable>,
	<mailto:freebsd-stable-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 07 Aug 2003 12:30:31 -0000

Since I upgraded to FreeBSD 4.8 (from 4.5) I've noticed occasional failures
of nvi.  It will suddenly die as a key is pressed, emitting:

Error: input: Resource temporarily unavailable

and you are staring at your command prompt.

I googled for this message and found that people here and there have been
complaining of this since about FreeBSD 4.2, but that absolutely none of
them have received a reply.

What's going on here?  Down in the bowels of nvi a read of the pty returns
EAGAIN and that is treated as fatal.  This should only occur with read() if
the input is non-blocking, and as far as I can tell it isn't.

So, is this a nvi bug (read() returning EAGAIN should be non-fatal)?  Is
this a pty bug (read() incorrectly returning EAGAIN)?  Perhaps it could be
even an xterm bug?  (Since I also upgraded to the XFree86 4.x series when I
upgraded to FreeBSD 4.8 and maybe those other folks were early adopters).

Any ideas?

Stephen.