From owner-freebsd-hackers Wed Sep 25 8:14: 8 2002 Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.FreeBSD.org (mx1.FreeBSD.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 6FDA937B401 for ; Wed, 25 Sep 2002 08:14:07 -0700 (PDT) Received: from dan.emsphone.com (dan.emsphone.com [199.67.51.101]) by mx1.FreeBSD.org (Postfix) with ESMTP id CCA1C43E4A for ; Wed, 25 Sep 2002 08:14:06 -0700 (PDT) (envelope-from dan@dan.emsphone.com) Received: (from dan@localhost) by dan.emsphone.com (8.12.6/8.12.5) id g8PFDwbt095684; Wed, 25 Sep 2002 10:13:58 -0500 (CDT) (envelope-from dan) Date: Wed, 25 Sep 2002 10:13:58 -0500 From: Dan Nelson To: Julian Stacey Cc: Paolo Pisati , freebsd-hackers@FreeBSD.ORG Subject: Re: Hey, is there space for a newbie? =) Message-ID: <20020925151358.GD16302@dan.emsphone.com> References: <20020924175642.GB87963@southcross.skynet.org> <200209250958.g8P9wXE10208@flip.jhs.private> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <200209250958.g8P9wXE10208@flip.jhs.private> X-OS: FreeBSD 5.0-CURRENT X-message-flag: Outlook Error User-Agent: Mutt/1.5.1i Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG In the last episode (Sep 25), Julian Stacey said: > > -a fs with journaling: some times ago, i would like to develop my > > own fs with journaling, but right now i could even drop the dream > > of my own fs and JUST port the xfs/jfs for FreeBSD.. > > Journaling would support user level "Undelete" I presume ? That > would make BSD more attractive to Micro$oft users, used to the luxury > of "Undelete". You don't need journaling for undelete capability. When you delete a file on Netware, the file is simply marked "deleted" but the filename stays in the directory, and duplicate deleted filenames are allowed. When true free disk space gets low, deleted files are purged in the background, oldest first (I believe). There is an API for listing, salvaging, and manually purging deleted files. I know Netware 3 had salvage capabilities, and it certainly didn't have a journalling FS :) You might be able to misuse the Whiteout file type in FFS to present a similar user interface. unlink(2) would rename the file to filename.timestamp and whiteoute it. ls -W, rm -W, and rm would list, salvage, and purge, respectively. Since S_IFWHT is a filetype, you would have to only allow file deletion, or encode the original filetype somewhere else. Alternatively, you could add a file flag equivalent to whiteout. "invisible" or something, and use chflags to salvage. -- Dan Nelson dnelson@allantgroup.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message