From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Andreas Schwab Newsgroups: gmane.emacs.devel Subject: Re: busyloop in sigchld_handler Date: Wed, 14 Mar 2007 11:22:51 +0100 Message-ID: References: <45F59395.4010708@gnu.org> <45F5A2B4.7090301@gnu.org> <85ejnumf1o.fsf@lola.goethe.zz> <868xe11tzu.fsf@lola.quinscape.zz> <85abyglrbs.fsf@lola.goethe.zz> <85tzwokb4x.fsf@lola.goethe.zz> <86tzwoxq1q.fsf@lola.quinscape.zz> <86odmww3dy.fsf@lola.quinscape.zz> NNTP-Posting-Host: lo.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable X-Trace: sea.gmane.org 1173867799 17658 80.91.229.12 (14 Mar 2007 10:23:19 GMT) X-Complaints-To: usenet@sea.gmane.org NNTP-Posting-Date: Wed, 14 Mar 2007 10:23:19 +0000 (UTC) Cc: Sam Steingold , emacs-devel@gnu.org, "Kim F. Storm" To: David Kastrup Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Wed Mar 14 11:23:13 2007 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([199.232.76.165]) by lo.gmane.org with esmtp (Exim 4.50) id 1HRQdT-0003t2-09 for ged-emacs-devel@m.gmane.org; Wed, 14 Mar 2007 11:23:11 +0100 Original-Received: from localhost ([127.0.0.1] helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1HRQeK-00045v-R5 for ged-emacs-devel@m.gmane.org; Wed, 14 Mar 2007 05:24:04 -0500 Original-Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1HRQeG-0003ws-Dg for emacs-devel@gnu.org; Wed, 14 Mar 2007 06:24:00 -0400 Original-Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1HRQeD-0003jC-CE for emacs-devel@gnu.org; Wed, 14 Mar 2007 06:23:59 -0400 Original-Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1HRQeD-0003iW-6j for emacs-devel@gnu.org; Wed, 14 Mar 2007 05:23:57 -0500 Original-Received: from ns.suse.de ([195.135.220.2] helo=mx1.suse.de) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1HRQdC-0003Lf-Hk; Wed, 14 Mar 2007 06:22:54 -0400 Original-Received: from Relay1.suse.de (mail2.suse.de [195.135.221.8]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.suse.de (Postfix) with ESMTP id C3BE212295; Wed, 14 Mar 2007 11:22:51 +0100 (CET) X-Yow: Yow! We're going to a new disco! In-Reply-To: <86odmww3dy.fsf@lola.quinscape.zz> (David Kastrup's message of "Wed, 14 Mar 2007 11:00:57 +0100") User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/22.0.91 (gnu/linux) X-detected-kernel: Linux 2.4-2.6 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Original-Sender: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:67918 Archived-At: David Kastrup writes: > The signal manpage says: > > When a signal occurs, and func points to a function, it is > implementation-defined whether the equivalent of a: > > signal(sig, SIG_DFL); > > is executed or the implementation prevents some > implementation-defined set of signals (at least including > sig) from occurring until the current signal handling has > completed. > > So even though SIGCHLD may be interrupted by another signal, this does > not mean that the other signal handler gets a chance to run. This is a complete red herring. The Linux kernel (and all XSI compliant systems) always blocks the invoking signal when a handler is invoked. Andreas. --=20 Andreas Schwab, SuSE Labs, schwab@suse.de SuSE Linux Products GmbH, Maxfeldstra=DFe 5, 90409 N=FCrnberg, Germany PGP key fingerprint =3D 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED= 5 "And now for something completely different."