From owner-freebsd-current  Sat Apr  8 21:00:02 1995
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To: Christoph Kukulies <kuku@gilberto.physik.rwth-aachen.de>
cc: joerg_wunsch@uriah.heep.sax.de,
        freebsd-current@freefall.cdrom.com (user alias)
Subject: Re: should su retain ${DISPLAY} 
In-reply-to: Your message of "Sat, 08 Apr 95 19:36:36 +0200."
             <199504081736.TAA10286@gilberto.physik.rwth-aachen.de> 
Date: Sat, 08 Apr 1995 21:00:00 -0700
Message-ID: <1112.797400000@freefall.cdrom.com>
From: "Jordan K. Hubbard" <jkh@freefall.cdrom.com>
Sender: current-owner@FreeBSD.org
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> Excuse my ignorance: What does su - do? I don't see it documented. It looks
> like it executes roots dotfiles.  I also see $DISPLAY preserved during a
> normal 'su'.

It executes the dotfiles for whichever user you're su'ing to.  I think
of `su -' as "su, but flush my current environment totally and adopt
that of the user I'm su'ing to."

It is therefore arguable that not preserving DISPLAY in these cases
is, in fact, the right thing to do.

						Jordan