From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: ludo@gnu.org (Ludovic =?iso-8859-1?Q?Court=E8s?=) Newsgroups: gmane.lisp.guile.devel Subject: Re: "no duplicate" in `popen.test' Date: Tue, 18 Mar 2008 22:13:50 +0100 Message-ID: <87bq5bka5t.fsf@gnu.org> References: <87wso5livc.fsf@gnu.org> <87od9dc657.fsf@ossau.uklinux.net> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit X-Trace: ger.gmane.org 1205874877 6774 80.91.229.12 (18 Mar 2008 21:14:37 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 18 Mar 2008 21:14:37 +0000 (UTC) To: guile-devel@gnu.org Original-X-From: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Tue Mar 18 22:15:03 2008 Return-path: Envelope-to: guile-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1Jbj94-000128-2n for guile-devel@m.gmane.org; Tue, 18 Mar 2008 22:14:54 +0100 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Jbj8U-0005fw-3Z for guile-devel@m.gmane.org; Tue, 18 Mar 2008 17:14:18 -0400 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1Jbj8P-0005fh-4h for guile-devel@gnu.org; Tue, 18 Mar 2008 17:14:13 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1Jbj8N-0005fV-MR for guile-devel@gnu.org; Tue, 18 Mar 2008 17:14:12 -0400 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Jbj8N-0005fS-Jc for guile-devel@gnu.org; Tue, 18 Mar 2008 17:14:11 -0400 Original-Received: from main.gmane.org ([80.91.229.2] helo=ciao.gmane.org) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1Jbj8N-0007yh-F2 for guile-devel@gnu.org; Tue, 18 Mar 2008 17:14:11 -0400 Original-Received: from list by ciao.gmane.org with local (Exim 4.43) id 1Jbj8D-0006lw-EF for guile-devel@gnu.org; Tue, 18 Mar 2008 21:14:01 +0000 Original-Received: from reverse-83.fdn.fr ([80.67.176.83]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Tue, 18 Mar 2008 21:14:01 +0000 Original-Received: from ludo by reverse-83.fdn.fr with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Tue, 18 Mar 2008 21:14:01 +0000 X-Injected-Via-Gmane: http://gmane.org/ Original-Lines: 39 Original-X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: reverse-83.fdn.fr X-Revolutionary-Date: 29 =?iso-8859-1?Q?Vent=F4se?= an 216 de la =?iso-8859-1?Q?R=E9volution?= X-PGP-Key-ID: 0xEB1F5364 X-PGP-Key: http://www.laas.fr/~lcourtes/ludovic.asc X-PGP-Fingerprint: 821D 815D 902A 7EAB 5CEE D120 7FBA 3D4F EB1F 5364 X-OS: i686-pc-linux-gnu User-Agent: Gnus/5.11 (Gnus v5.11) Emacs/22.1 (gnu/linux) Cancel-Lock: sha1:u+P7irti7lZJc843CxTtKXrYTzM= X-detected-kernel: by monty-python.gnu.org: Linux 2.6, seldom 2.4 (older, 4) X-BeenThere: guile-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Developers list for Guile, the GNU extensibility library" List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Errors-To: guile-devel-bounces+guile-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.lisp.guile.devel:7082 Archived-At: Hi Neil, Neil Jerram writes: > ludo@gnu.org (Ludovic Courtès) writes: > >> Hello, >> >> That "no duplicate" test in `popen.test' leaves a zombie behind it [0]. >> The fix would be to `waitpid' the process created by `open-input-pipe' >> (see attached patch), but that makes it hang, waiting for "sleep 999" to >> complete. > > I've attached an alternative possible solution, using feedback from > the parent to the child to avoid needing the long sleep. Good idea. It apparently fixes the problem. I think we also need that change in the second "no duplicate" test, don't we? > Unfortunately, though, I didn't manage to observe the zombie process > with the test as it was before. (How do I do this on GNU/Linux?) So > I don't really know whether this is a significant improvement. You can just run "./check-guile && pstree -u $USER". That shows whether there are any processes left (whether zombie or not). "ps" can then tell whether these are zombies, when marked with a `Z'. >> I'm not sure whether it's an indication that the bug was caught, or >> rather an indication that the test is broken, especially since I don't >> fully understand the bug that it's trying to catch. > > If waitpid fixes it, doesn't that point to the test being broken? Hmm, I don't know, why? Thanks, Ludovic.