From owner-cvs-src@FreeBSD.ORG Fri Apr 16 08:34:23 2004 Return-Path: Delivered-To: cvs-src@freebsd.org Received: from green.homeunix.org (freefall.freebsd.org [216.136.204.21]) by hub.freebsd.org (Postfix) with ESMTP id DB26616A4CE; Fri, 16 Apr 2004 08:34:22 -0700 (PDT) Received: from localhost (green@localhost [127.0.0.1]) by green.homeunix.org (8.12.11/8.12.11) with ESMTP id i3GFYMx0027058; Fri, 16 Apr 2004 11:34:22 -0400 (EDT) (envelope-from green@green.homeunix.org) Message-Id: <200404161534.i3GFYMx0027058@green.homeunix.org> X-Mailer: exmh version 2.6.3 04/04/2003 with nmh-1.0.4 To: obrien@FreeBSD.org In-Reply-To: Message from "David O'Brien" <20040416150742.GA16010@dragon.nuxi.com> From: "Brian F. Feldman" Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Fri, 16 Apr 2004 11:34:22 -0400 Sender: green@green.homeunix.org cc: cvs-src@FreeBSD.org cc: src-committers@FreeBSD.org cc: cvs-all@FreeBSD.org Subject: Re: cvs commit: src/sbin/dump dump.8 dump.h main.c tape.c src/sbin/restore extern.h main.c restore.8 tape.c X-BeenThere: cvs-src@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: CVS commit messages for the src tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 16 Apr 2004 15:34:23 -0000 "David O'Brien" wrote: > On Mon, Apr 12, 2004 at 07:58:07PM -0700, Brian Feldman wrote: > > green 2004/04/12 19:58:07 PDT > > > > FreeBSD src repository > > > > Modified files: > > sbin/dump dump.8 dump.h main.c tape.c > > sbin/restore extern.h main.c restore.8 tape.c > > Log: > > Add -P arguments for dump(8) and restore(8) which allow the user to > > use backup methods other than files and tapes. The -P argument is > > a normal sh(1) pipeline with either $DUMP_VOLUME or $RESTORE_VOLUME > > defined in the environment, respectively. > > Why do you need an option for this? Can't you just use 'dump ... |' and > '... | restore'? You can do that if you want to just dump a single volume and manually split it, but if you want to actually dump actual dump volumes, you run into problems. Your pipeline would be outside dump, so it would have no knowledge of when one volume ends and another begins. There are plenty of inelegant solutions to that requiring twice the operator intervention, but I prefer this elegant solution. It's not perfect, though: auto-sizing would require having the dump pipeline child knowing when reading from dump(8) would be causing an EOF on the media and shutting down before it reads that block. -- Brian Fundakowski Feldman \'[ FreeBSD ]''''''''''\ <> green@FreeBSD.org \ The Power to Serve! \ Opinions expressed are my own. \,,,,,,,,,,,,,,,,,,,,,,\