From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Sean McAfee Newsgroups: gmane.emacs.help Subject: Weird interaction between chroot jail and shell-mode Date: Sat, 30 Oct 2010 13:17:32 -0700 Message-ID: NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Trace: dough.gmane.org 1291893109 8939 80.91.229.12 (9 Dec 2010 11:11:49 GMT) X-Complaints-To: usenet@dough.gmane.org NNTP-Posting-Date: Thu, 9 Dec 2010 11:11:49 +0000 (UTC) To: help-gnu-emacs@gnu.org Original-X-From: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Thu Dec 09 12:11:42 2010 Return-path: Envelope-to: geh-help-gnu-emacs@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1PQePW-0002Xe-LJ for geh-help-gnu-emacs@m.gmane.org; Thu, 09 Dec 2010 12:11:42 +0100 Original-Received: from localhost ([127.0.0.1]:47873 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PQePV-00062d-10 for geh-help-gnu-emacs@m.gmane.org; Thu, 09 Dec 2010 06:11:41 -0500 Original-Path: usenet.stanford.edu!postnews.google.com!news1.google.com!Xl.tags.giganews.com!border1.nntp.dca.giganews.com!nntp.giganews.com!local2.nntp.dca.giganews.com!nntp.supernews.com!news.supernews.com.POSTED!not-for-mail Original-NNTP-Posting-Date: Sat, 30 Oct 2010 15:17:33 -0500 Original-Newsgroups: gnu.emacs.help User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.3 (darwin) Cancel-Lock: sha1:UqbXfBpANrMZ8ujaMr4RCYXZhb4= Original-Lines: 38 Original-X-Trace: sv3-IDPzRrAOHFMrrg7m8bxtbP4HhULNrxiRawOqPP/D41f2i7lAJcUVnTUvBu6Hrram5CI4rMrDHZ3pZzN!qx4vsPfL57ahUmp+1gEBZ+Yl5TnSlBAPBegh5LLGYd3UmX31RXTQPNSViOw= Original-X-Complaints-To: www.supernews.com/docs/abuse.html X-DMCA-Complaints-To: www.supernews.com/docs/dmca.html X-Abuse-and-DMCA-Info: Please be sure to forward a copy of ALL headers X-Abuse-and-DMCA-Info: Otherwise we will be unable to process your complaint properly X-Postfilter: 1.3.40 X-Original-Bytes: 2849 Original-Xref: usenet.stanford.edu gnu.emacs.help:182127 X-BeenThere: help-gnu-emacs@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Users list for the GNU Emacs text editor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Errors-To: help-gnu-emacs-bounces+geh-help-gnu-emacs=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.help:76981 Archived-At: This is probably the most perplexing Emacs issue I've ever encountered... I've been trying to build the debian "apt" package in a shell-mode bash shell, inside of which I've entered a chroot jail. The build process (initiated with the command "dpkg-buildpackage") would reach a point where it executes the command: po4a --previous --no-backups po4a.conf ...whereupon the command hangs, consuming 100% of the CPU until I kill it. A co-worker had no trouble building the package in an ordinary terminal window on his own machine, and, unable to find any reason for my issue, suggested that Emacs might be to blame. I was dubious, to say the least, but to humor him I repeated the process in my own terminal window. To my astonishment, the package didn't get hung up on the po4a command, but ran to completion successfully. I tried building the package inside a terminal emulator window inside Emacs. It built. I tried again using eshell, which I ordinarily never use. The build got hung up at the same point as originally, with the additional delightfulness that I couldn't interrupt the hung command with C-c C-c. Finally, I tried building the package in a shell-mode shell again, but without entering the chroot jail. It built. WTF. I tried dumping my environment variables in the jail in shell-mode and term-mode and comparing them. The only differences were in OLDPWD, LSCOLORS, and TERM ("dumb" in shell-mode, "vt100" in term-mode). I repeated the build in shell-mode after setting TERM to vt100, but it still got hung. I am utterly perplexed. Does anyone have any possible explanation for the behavior I'm seeing? How in the world can any command produce different behavior when run inside vs. outside of a chroot jail, but only when run from a bash shell which itself is running inside a shell-mode buffer?