From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Alain Schneble Newsgroups: gmane.emacs.devel Subject: Re: Asynchronous DNS Date: Sat, 20 Feb 2016 20:31:06 +0100 Message-ID: <86a8mv41s5.fsf@realize.ch> References: <83a8nk1cxk.fsf@gnu.org> <87h9hrnc8x.fsf@gnus.org> <83powfzsqt.fsf@gnu.org> <87y4b393hl.fsf@gnus.org> <83io27ytu3.fsf@gnu.org> <87k2mmzkry.fsf@gnus.org> <83k2mlyet8.fsf@gnu.org> <87lh71nriy.fsf@gnus.org> <8637t8opla.fsf@realize.ch> <871t8skg6c.fsf@gnus.org> <86y4b0n5q2.fsf@realize.ch> <87fux7gb7o.fsf@gnus.org> <83wpqjvd2f.fsf@gnu.org> <87zivfobn4.fsf@gnus.org> <86y4ao5g1c.fsf@realize.ch> <87r3ggdo9f.fsf@gnus.org> <86twlb5yl4.fsf@realize.ch> <83d1rzz1mu.fsf@gnu.org> <86egcc49qu.fsf@realize.ch> <87io1k41cg.fsf@gnus.org> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1455996756 2032 80.91.229.3 (20 Feb 2016 19:32:36 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Sat, 20 Feb 2016 19:32:36 +0000 (UTC) To: Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Sat Feb 20 20:32:28 2016 Return-path: Envelope-to: ged-emacs-devel@m.gmane.org Original-Received: from lists.gnu.org ([208.118.235.17]) by plane.gmane.org with esmtp (Exim 4.69) (envelope-from ) id 1aXDGQ-0007hr-1q for ged-emacs-devel@m.gmane.org; Sat, 20 Feb 2016 20:32:22 +0100 Original-Received: from localhost ([::1]:35146 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aXDGP-0005PZ-4Z for ged-emacs-devel@m.gmane.org; Sat, 20 Feb 2016 14:32:21 -0500 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:54964) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aXDG6-0005Oj-7u for emacs-devel@gnu.org; Sat, 20 Feb 2016 14:32:06 -0500 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aXDG1-00047Q-Qu for emacs-devel@gnu.org; Sat, 20 Feb 2016 14:32:02 -0500 Original-Received: from clientmail.realize.ch ([46.140.89.53]:4535) by eggs.gnu.org with smtp (Exim 4.71) (envelope-from ) id 1aXDG1-000477-E8 for emacs-devel@gnu.org; Sat, 20 Feb 2016 14:31:57 -0500 Original-Received: from rintintin.hq.realize.ch.lan.rit ([192.168.0.105]) by clientmail.realize.ch ; Sat, 20 Feb 2016 20:31:49 +0100 Original-Received: from MYNGB (192.168.66.64) by rintintin.hq.realize.ch.lan.rit (192.168.0.105) with Microsoft SMTP Server (TLS) id 15.0.516.32; Sat, 20 Feb 2016 20:31:28 +0100 In-Reply-To: <87io1k41cg.fsf@gnus.org> (Lars Ingebrigtsen's message of "Sat, 20 Feb 2016 12:28:15 +1100") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.4 (windows-nt) X-ClientProxiedBy: rintintin.hq.realize.ch.lan.rit (192.168.0.105) To rintintin.hq.realize.ch.lan.rit (192.168.0.105) X-detected-operating-system: by eggs.gnu.org: Windows NT kernel [generic] X-Received-From: 46.140.89.53 X-BeenThere: emacs-devel@gnu.org X-Mailman-Version: 2.1.14 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-bounces+ged-emacs-devel=m.gmane.org@gnu.org Xref: news.gmane.org gmane.emacs.devel:200335 Archived-At: Lars Ingebrigtsen writes: > I had assumed that getaddrinfo_a would have the normal timeouts that > getaddrinfo has -- that it would say that it's failed after a certain > number of seconds. Some testing here (switching off the wifi after > issuing a DNS request) seems to indicate that that may not be the case? I was just looking into the glibc implementation of getaddrinfo_a again. It invokes getaddrinfo from its worker threads and it seems like it should not behave differently regarding timeouts. The only timeout I found was to make the worker threads sleep when there is nothing to do. But they should get woken up if a new request arrives or they will eventually die when the timeout has elapsed. But all this should not be related to the timeout you are referring to. > I couldn't find anything in the documentation about this... am I > overlooking something? If not, I have to implement some timeouts myself > in that code. But what seems strange to me right now is this code in check_for_dns: /* The DNS lookup failed. */ else if (!EQ (p->status, Qconnect)) { ... Actually, I tried it out and DNS lookups seem to timeout quite fast on my machine if there is no network connection. But they do not enter the if-branch above. That seems like an error. Am I day-dreaming or shouldn't it be rewritten to look like this? /* The DNS lookup failed. */ else if (EQ (p->status, Qconnect)) { ...