From owner-freebsd-questions@freebsd.org Tue Jul 25 19:54:17 2017 Return-Path: Delivered-To: freebsd-questions@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id C1FD5D7CCCE for ; Tue, 25 Jul 2017 19:54:17 +0000 (UTC) (envelope-from freebsd@edvax.de) Received: from mailrelay14.qsc.de (mailrelay14.qsc.de [212.99.163.154]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client CN "*.antispameurope.com", Issuer "TeleSec ServerPass DE-2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 3E0DF641BE for ; Tue, 25 Jul 2017 19:54:16 +0000 (UTC) (envelope-from freebsd@edvax.de) Received: from mx01.qsc.de ([213.148.129.14]) by mailrelay14.qsc.de; Tue, 25 Jul 2017 21:53:40 +0200 Received: from r56.edvax.de (port-92-195-203-176.dynamic.qsc.de [92.195.203.176]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx01.qsc.de (Postfix) with ESMTPS id 5327B3CC3F; Tue, 25 Jul 2017 21:53:39 +0200 (CEST) Received: from r56.edvax.de (localhost [127.0.0.1]) by r56.edvax.de (8.14.5/8.14.5) with SMTP id v6PJrciX002939; Tue, 25 Jul 2017 21:53:38 +0200 (CEST) (envelope-from freebsd@edvax.de) Date: Tue, 25 Jul 2017 21:53:38 +0200 From: Polytropon To: Manish Jain Cc: "byrnejb@harte-lyne.ca" , "James B. Byrne via freebsd-questions" Subject: Re: FreeBSD-11, Mate, Terminal, Gvim Message-Id: <20170725215338.41ea83f0.freebsd@edvax.de> In-Reply-To: References: <20170725210647.6f4c8fcd.freebsd@edvax.de> Reply-To: Polytropon Organization: EDVAX X-Mailer: Sylpheed 3.1.1 (GTK+ 2.24.5; i386-portbld-freebsd8.2) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-cloud-security-sender: freebsd@edvax.de X-cloud-security-recipient: freebsd-questions@freebsd.org X-cloud-security-Virusscan: CLEAN X-cloud-security-disclaimer: This E-Mail was scanned by E-Mailservice on mailrelay14.qsc.de with F354C683B36 X-cloud-security-connect: mx01.qsc.de[213.148.129.14], TLS=1, IP=213.148.129.14 X-cloud-security: scantime:.1297 X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 25 Jul 2017 19:54:17 -0000 On Tue, 25 Jul 2017 19:45:18 +0000, Manish Jain wrote: > > > On 07/26/17 00:36, Polytropon wrote: > > On Tue, 25 Jul 2017 10:39:29 -0400, James B. Byrne via freebsd-questions wrote: > >> When setting up new hosts I usually open an especially coloured > >> terminal instance and use 'su -l' to become root. I also typically > >> edit using gvim. However, this combination does not work for me on > >> FreeBSD with Mate as it did for me under CentOD-6 and Gnome2. When > >> inside a terminal window as root instead of opening an Xwindow editor > >> when running gvim I get a 'E233: cannot open display' error. > > > > This is to be expected. > > > > With "su -l", a full login is simulated, so all environmental > > variables will be reset - but $DISPLAY is needed for X. There > > are basically two solutions: > > > > 1. Set $DISPLAY accordingly, for example to :0.0. Refer to the > > documentation of your shell on how to do it, for example in > > C shell "setenv DISPLAY :0.0", in sh/bash "export DISPLAY=:0.0". > > > > 2. Use "su -m" instead, which will preserve the environment of > > your user, and $DISPLAY will be kept set. > > > > See "man su" for details. > > Hi Poly, > > I found this relevant too. Under Linux. it appears that root is somehow > able to connect to the X server of the current user. But under FreeBSD, > this does not work and occasionally I need to run X applications as root. > > Your steps should in theory work. But apparently, they don't on my box. > > export DISPLAY=:0.0 > su -m my_normal_user_name -c gvim > > I get : > > No protocol specified > E233: cannot open display > Press ENTER or type command to continue Use "su -m" from your user's account, not from the root account. This should work - you can test if $DISPLAY is still set. Example: % su -l Password: # echo $DISPLAY DISPLAY: Undefined variable. # xlogo Error: Can't open display: # exit % su -m Password: # echo $DISPLAY :0.0 # xlogo (X logo is being shown) ^C # exit % _ This is C shell "decoration": % for user, # for root. :-) > Actually, xhost itself is unable to access the display : > > /root <<: xhost +local: > No protocol specified > xhost: unable to open display ":0.0" That is correct. Like "su -m", "xhost" is to be executed from the (non-root) user that controls the display. But when you're using the "su -m" approach, it usually isn't even needed. -- Polytropon Magdeburg, Germany Happy FreeBSD user since 4.0 Andra moi ennepe, Mousa, ...