From owner-freebsd-hackers Thu Nov 18 10:41:34 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from wall.polstra.com (rtrwan160.accessone.com [206.213.115.74]) by hub.freebsd.org (Postfix) with ESMTP id 9BF2415490 for ; Thu, 18 Nov 1999 10:41:18 -0800 (PST) (envelope-from jdp@polstra.com) Received: from vashon.polstra.com (vashon.polstra.com [206.213.73.13]) by wall.polstra.com (8.9.3/8.9.3) with ESMTP id KAA24422; Thu, 18 Nov 1999 10:41:01 -0800 (PST) (envelope-from jdp@polstra.com) From: John Polstra Received: (from jdp@localhost) by vashon.polstra.com (8.9.3/8.9.1) id KAA03119; Thu, 18 Nov 1999 10:40:59 -0800 (PST) (envelope-from jdp@polstra.com) Date: Thu, 18 Nov 1999 10:40:59 -0800 (PST) Message-Id: <199911181840.KAA03119@vashon.polstra.com> To: robert+freebsd@cyrus.watson.org Subject: Re: Portable way to compare struct stat's? In-Reply-To: References: Organization: Polstra & Co., Seattle, WA Cc: hackers@freebsd.org Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG In article , Robert Watson wrote: > On Mon, 15 Nov 1999, Wes Peters wrote: > > > On a single system, if st_dev and st_ino are equal, you must be > > referring to the same object. If not, I'd like to hear about it. > > This assumption has always caused lots of pain and suffering for > distributed file system people -- in a distributed file system, the > requirement that you can generate a unique 32 bit number for each > file or directory visible in the FS is a fairly arduous one. I don't dispute that point, but it is worth mentioning that POSIX specifically guarantees that st_dev and st_ino "taken together uniquely identify the file within the system." So it is OK for applications to rely on that. John -- John Polstra jdp@polstra.com John D. Polstra & Co., Inc. Seattle, Washington USA "No matter how cynical I get, I just can't keep up." -- Nora Ephron To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message