From owner-freebsd-arch Thu Mar 1 8:35:48 2001 Delivered-To: freebsd-arch@freebsd.org Received: from peach.ocn.ne.jp (peach.ocn.ne.jp [210.145.254.87]) by hub.freebsd.org (Postfix) with ESMTP id 8B8EA37B71A; Thu, 1 Mar 2001 08:35:42 -0800 (PST) (envelope-from dcs@newsguy.com) Received: from newsguy.com (p04-dn02kiryunisiki.gunma.ocn.ne.jp [211.0.245.69]) by peach.ocn.ne.jp (8.9.1a/OCN/) with ESMTP id BAA23249; Fri, 2 Mar 2001 01:35:27 +0900 (JST) Message-ID: <3A9E79A1.C56F93DF@newsguy.com> Date: Fri, 02 Mar 2001 01:32:33 +0900 From: "Daniel C. Sobral" X-Mailer: Mozilla 4.7 [en] (Win98; I) X-Accept-Language: en,pt-BR MIME-Version: 1.0 To: Garrett Wollman Cc: rwatson@FreeBSD.ORG, arch@FreeBSD.ORG Subject: Re: Arch question for a UDF FS driver References: <200103011420.JAA00305@khavrinen.lcs.mit.edu> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Garrett Wollman wrote: > > >There are, unfortunately, a few apps that make use of the inode > >number returned by stat -- generally to try and detect hard links (I > >think tar does this). > > As I have pointed out before, it is a requirement of POSIX that > distinct files have distinct (device, inode) pairs. The individual > st_dev and st_ino values are not required to have any particular > meaning except when used together in this way. (So, it's possible to > treat the pair of members as a single 64-bit quantity, should that be > desired, provided that uniqueness can be guaranteed.) And as have been answered before, that POSIX requirement is not viable with some modern distributed filesystems. Some have identifiers greater than 64 bits. And some do not have identifiers that uniquely identify a file at all (you'd have to compare each new identifier acquired with all cached identifiers to check for uniqueness). -- Daniel C. Sobral (8-DCS) dcs@newsguy.com dcs@freebsd.org capo@the.obscure.bsdconspiracy.net I think you are delusional, but that is OK. Its part of your natural charm! To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message