From mboxrd@z Thu Jan 1 00:00:00 1970 Path: news.gmane.org!not-for-mail From: Michael Albinus Newsgroups: gmane.emacs.devel Subject: Re: tramp ControlMaster options Date: Tue, 21 Jul 2015 07:53:30 +0200 Message-ID: <87vbde2h0l.fsf@gmx.de> References: <55AA4AF3.2030901@thregr.org> <87zj2rv16b.fsf@gmx.de> <871tg3z6we.fsf@gmail.com> <55ACAC48.1000600@thregr.org> <871tg24qlh.fsf@gmx.de> <87mvyqjdv0.fsf@gmail.com> NNTP-Posting-Host: plane.gmane.org Mime-Version: 1.0 Content-Type: text/plain X-Trace: ger.gmane.org 1437458044 24018 80.91.229.3 (21 Jul 2015 05:54:04 GMT) X-Complaints-To: usenet@ger.gmane.org NNTP-Posting-Date: Tue, 21 Jul 2015 05:54:04 +0000 (UTC) Cc: emacs-devel@gnu.org To: Thierry Volpiatto Original-X-From: emacs-devel-bounces+ged-emacs-devel=m.gmane.org@gnu.org Tue Jul 21 07:53:55 2015 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 1ZHQV1-0008L4-IG for ged-emacs-devel@m.gmane.org; Tue, 21 Jul 2015 07:53:55 +0200 Original-Received: from localhost ([::1]:58062 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZHQV0-0007HN-TV for ged-emacs-devel@m.gmane.org; Tue, 21 Jul 2015 01:53:54 -0400 Original-Received: from eggs.gnu.org ([2001:4830:134:3::10]:36749) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZHQUj-0007FY-By for emacs-devel@gnu.org; Tue, 21 Jul 2015 01:53:38 -0400 Original-Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZHQUf-0008BB-0g for emacs-devel@gnu.org; Tue, 21 Jul 2015 01:53:37 -0400 Original-Received: from mout.gmx.net ([212.227.15.15]:61048) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZHQUe-0008Ah-Nd for emacs-devel@gnu.org; Tue, 21 Jul 2015 01:53:32 -0400 Original-Received: from detlef.gmx.de ([87.146.55.21]) by mail.gmx.com (mrgmx002) with ESMTPSA (Nemesis) id 0MhAAr-1Zd44g25cP-00MHMM; Tue, 21 Jul 2015 07:53:31 +0200 In-Reply-To: <87mvyqjdv0.fsf@gmail.com> (Thierry Volpiatto's message of "Tue, 21 Jul 2015 07:09:39 +0200") User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/24.4 (gnu/linux) X-Provags-ID: V03:K0:chO0prEaeINz2VNuwwtWkMDV2s1UiDWwl0AaM4myPpUQkXhEurv 8OTlfbtQevrOpXZ9oyXQCcK6cwubBa9j5ml93iFiucbUPvRtGmtIy4rTCuZ8ITdnBRKozPW Gvrh+2Ox5wFamQbHbnaSDAhMoghxELgCWp5MdvBZ6tHNuWQnSPPUFTLtPHe8lNGQceeFkwH 0T+rfgiBeCwrlVDpF+szQ== X-UI-Out-Filterresults: notjunk:1;V01:K0:eKxV1Vx+IMU=:nHhNRuEM7pmV/M/mD7vSjR 7qiZ6FxGIYVQgjR7y5YyjCSD1F3KSHaAudQagZ1USpRJ1UtGOCgTt7r4N8dCW8VFLvn6eun6s kLX63RoS3SY3yo1FGZXIU6gl2GetIZz4Zz2o/BkY4PB552aefQ4IZjio45AUyCupjUHKrfP1o kdDYUOHUbKJMN1+3PgPekJHUM6gKe/64QS5gLfnSy/97AQTAUc5kab/mUB68HairQaSOE5jW5 cHYdsh1IQV4wmRvHTfpU+FR2mdwY9E/wPckzHR2CCg3Z+3aCMqbl9s4DKyf0/xkcF61LYXPUQ l74IuGCWKEwLvNiFKdSOrP/SLwsC2TFPo5+ZHxqn3G8fe88AqVr6fDGs7mkM7ozprc13BFtg0 UznB0Nj/NxPRolCqDjcXR+a2stX9OcSMD8ys62uwcnf/801dUTDuvhSVhD8NZVOtrs0ixWLWr RUbPvpcrKYdzIelHTKAcRwj/itCaqqTFOyOWHv1KO5CY0o8ECzYikJAd5BHSqJfQvXC/QA6Pn q8IE/QhuMvyV85Xt8y0ynNh3aIsBEYqMF4xQW3M1uTsDO6k2LAM1RZvqcX1VB6Zf+QQyn8diX 3K3zc6EM8XvlS9eTp88QdXy02QxSyePWDA4HJhqJtwEp8VMvNgxOOkrfsp6ZUx7gANWkUj7wW HmScEXEgh/0O1D8HxirlyExQI939EZ9aRNCiguz2yzJiice7NVjHb8C7I6WFS4Odquvw= X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x [generic] X-Received-From: 212.227.15.15 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:188026 Archived-At: Thierry Volpiatto writes: >> In emacs 24.5.1, I see this at line 310 of tramp.el: Here we are. What I have written is about Emacs 25, the development branch in git. > So IIUC tramp is calling ssh at load time when evaling its defcustom ?!! Not any longer. This is fixed, as I have explained. >>>> Any reason why we cannot use `ssh -o BatchMode=yes [various flags] >>>> 0.0.0.0' instead of using a domain name? This would greatly reduce the >>>> issue. >>> >>> The function (!) `tramp-ssh-controlmaster-options' uses "localhost" for >>> test. This shall avoid DNS requests. >> >> Still connects to a valid host, which might have a daemon running (in >> fact, I have one on localhost for debugging). >> >> If there's no reason to connect to something, call 0.0.0.0. I've tested. If there is a daemon running on your local host, it *also* connects using 0.0.0.0. No difference to localhost. --8<---------------cut here---------------start------------->8--- # ssh -o ControlPath=%C 0.0.0.0 Welcome to Ubuntu 15.04 (GNU/Linux 3.19.0-23-generic x86_64) * Documentation: https://help.ubuntu.com/ 0 packages can be updated. 0 updates are security updates. *** System restart required *** Last login: Mon Jul 20 20:41:09 2015 from localhost --8<---------------cut here---------------end--------------->8--- That's why *current* Tramp connects to another port, hoping nobody let run an sshd on that port. --8<---------------cut here---------------start------------->8--- # ssh -p 23 -o ControlPath=%C localhost ssh: connect to host localhost port 23: Connection refused --8<---------------cut here---------------end--------------->8--- > Isn't it possible to setup the default value of > `tramp-ssh-controlmaster-options' only when tramp is involved (i.e at > first connection) instead of evaling this at load time ? That's the case in recent Tramp. >> I love that tramp detects ControlMaster support in ssh, but calling >> external processes on load, if really needed, should /really/ be quick. It does now. In order to fix the problem for you, you could upgrade to the development branch of Emacs (25.0.50). If this is not an option for you, you might install Tramp 2.2.12, which has been released end of June. Another Emacs 24.x release is unlikely, as Stefan has said a while ago. > Thanks. Best regards, Michael.