From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!.POSTED!not-for-mail From: Paul Eggert Newsgroups: gmane.emacs.devel Subject: Re: SIGCHLD in vfork child context Date: Tue, 16 May 2017 01:58:37 -0700 Organization: UCLA Computer Science Department Message-ID: References: NNTP-Posting-Host: blaine.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable X-Trace: blaine.gmane.org 1494925158 30159 195.159.176.226 (16 May 2017 08:59:18 GMT) X-Complaints-To: usenet@blaine.gmane.org NNTP-Posting-Date: Tue, 16 May 2017 08:59:18 +0000 (UTC) User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 To: YAMAMOTO Mitsuharu , emacs-devel@gnu.org Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Tue May 16 10:59:15 2017 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by blaine.gmane.org with esmtp (Exim 4.84_2) (envelope-from ) id 1dAYK2-0007lQ-Ja for ged-emacs-devel@m.gmane.org; Tue, 16 May 2017 10:59:14 +0200 Original-Received: from localhost ([::1]:40538 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dAYK8-0000oL-2P for ged-emacs-devel@m.gmane.org; Tue, 16 May 2017 04:59:20 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:39653) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1dAYJX-0000oE-K9 for emacs-devel@gnu.org; Tue, 16 May 2017 04:58:44 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1dAYJU-0008RT-JA for emacs-devel@gnu.org; Tue, 16 May 2017 04:58:43 -0400 Original-Received: from zimbra.cs.ucla.edu ([131.179.128.68]:43578) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1dAYJU-0008Qr-Ct for emacs-devel@gnu.org; Tue, 16 May 2017 04:58:40 -0400 Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id EFCFE16007A; Tue, 16 May 2017 01:58:38 -0700 (PDT) Original-Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id atfPM-K59CsJ; Tue, 16 May 2017 01:58:38 -0700 (PDT) Original-Received: from localhost (localhost [127.0.0.1]) by zimbra.cs.ucla.edu (Postfix) with ESMTP id 482F5160083; Tue, 16 May 2017 01:58:38 -0700 (PDT) X-Virus-Scanned: amavisd-new at zimbra.cs.ucla.edu Original-Received: from zimbra.cs.ucla.edu ([127.0.0.1]) by localhost (zimbra.cs.ucla.edu [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id pjcR0r5AowdO; Tue, 16 May 2017 01:58:38 -0700 (PDT) Original-Received: from [192.168.1.9] (unknown [47.153.188.248]) by zimbra.cs.ucla.edu (Postfix) with ESMTPSA id 2AE0F16007A; Tue, 16 May 2017 01:58:38 -0700 (PDT) In-Reply-To: X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [fuzzy] X-Received-From: 131.179.128.68 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: "Emacs development discussions." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Original-Sender: "Emacs-devel" Xref: news.gmane.org gmane.emacs.devel:214875 Archived-At: YAMAMOTO Mitsuharu wrote: > It seems that calling waitpid from the SIGCHLD handler results in > ECHILD in the vfork child context Why is the vfork child process getting a SIGCHLD signal? That process doe= sn't=20 have any children. Is the macOS kernel simply buggy? If so, I suggest add= ing a=20 short explanation of the situation to this comment: > + /* Call the SIGCHLD handler in case we have received SIGCHLD in > + the vfork child context. The signal mask is restored by > + unblock_child_signal below. */ If not, then I don't understand the situation.... > + (*action.sa_handler) (SIGCHLD); No need for the * and the first set of parens. I.e., this is OK: action.sa_handler (SIGCHLD); Otherwise, looks OK; thanks.