From owner-freebsd-hackers@FreeBSD.ORG Fri Sep 5 14:32:21 2014 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 4A290D6B; Fri, 5 Sep 2014 14:32:21 +0000 (UTC) Received: from mail-pa0-x234.google.com (mail-pa0-x234.google.com [IPv6:2607:f8b0:400e:c03::234]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 18DE41CB8; Fri, 5 Sep 2014 14:32:21 +0000 (UTC) Received: by mail-pa0-f52.google.com with SMTP id eu11so22265822pac.25 for ; Fri, 05 Sep 2014 07:32:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=yBTWvP2e7yTK6dTHhYgoA1buWvHSN/ZSMpu1VV1cPr4=; b=OJIUjVnSEzrf0ULWLwccwfd/oRvt8iQNxH4DITtzd0hphjS1mJLi0V3KBbXQQgae+z bceqpGQNqzjxWlNPHwco2YH3Mey1wWCE2SxDA7tValJkLrAx0ONKrC1qTRalFfvhJ7Xr YR/gGGdz4s5zyHMUiqdzbWAJbbrWoMhX0nxM87mPNpDweUyPF66xItM7ChXFd8VVAPVm 9WL7XNvZOpJnJaTr3xDrIcG48xHzpI5FyMiLI+qTngjjdxKCbmEL6jxCAQzLdhae8T+r Kddqep3CzDOLDcP4t7IHoA2Y8aTzWig04h1/tizRicgfNwpoE2khfuqiR8tdhGHnOZoA 7lAA== MIME-Version: 1.0 X-Received: by 10.66.242.47 with SMTP id wn15mr22477728pac.64.1409927042863; Fri, 05 Sep 2014 07:24:02 -0700 (PDT) Received: by 10.70.93.169 with HTTP; Fri, 5 Sep 2014 07:24:02 -0700 (PDT) In-Reply-To: References: <718836647.19911209.1385302696963.JavaMail.root@uoguelph.ca> <706707CA-BD52-4814-BCCE-EB044B062BA6@kientzle.com> Date: Fri, 5 Sep 2014 16:24:02 +0200 Message-ID: Subject: Re: O_XATTR support in FreeBSD? From: Lionel Cons To: Tim Kientzle Content-Type: text/plain; charset=UTF-8 Cc: Rick Macklem , Cedric Blancher , Freebsd hackers list , Richard Yao , Pedro Giffuni , Jordan Hubbard X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 05 Sep 2014 14:32:21 -0000 On 1 December 2013 23:05, Lionel Cons wrote: > On 27 November 2013 05:52, Tim Kientzle wrote: >> >> On Nov 26, 2013, at 1:51 AM, Cedric Blancher wrote: >> >>> 5. Support for tar and pax is already there. Its described in >>> Solaris's fsattr man page, they use a extended header with filename >>> /dev/null (to prevent older tar versions from tripping over the new >>> headers) and then have a named attribute header which describes the >>> attributes names and flags. >> >> There are quite a few alternative approaches for storing >> extended attributes in tar and pax files. > > But this discussion is *not* about extended attributes, this > discussion is about Alternate Data Streams. Unfortunately the O_XATTR > discussion somehow started to cover the Linux "extended attribute > system", which is utterly useless in the intended use cases (as said, > no access through normal POSIX read(), write(), mmap(), no unlimited > size, no sparse data support (aka SEEK_HOLE, SEEK_DATA) etc etc). > > Lionel What is the status of O_XATTR (alias alternate data stream support) in FreeBSD? We run more and more into the trouble that these kind of streams are in use but cannot be accessed or processed on FreeBSD. Lionel