From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from pigeon.gentoo.org ([208.92.234.80] helo=lists.gentoo.org) by finch.gentoo.org with esmtp (Exim 4.60) (envelope-from ) id 1NDPmt-0004Sp-Rc for garchives@archives.gentoo.org; Wed, 25 Nov 2009 21:52:36 +0000 Received: from pigeon.gentoo.org (localhost [127.0.0.1]) by pigeon.gentoo.org (Postfix) with SMTP id 04EF6E0918; Wed, 25 Nov 2009 21:52:25 +0000 (UTC) Received: from smtp.gentoo.org (smtp.gentoo.org [140.211.166.183]) by pigeon.gentoo.org (Postfix) with ESMTP id C14CCE0918 for ; Wed, 25 Nov 2009 21:52:25 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp.gentoo.org (Postfix) with ESMTP id 5D726671A5 for ; Wed, 25 Nov 2009 21:52:25 +0000 (UTC) X-Virus-Scanned: amavisd-new at gentoo.org X-Spam-Score: -2.552 X-Spam-Level: X-Spam-Status: No, score=-2.552 required=5.5 tests=[AWL=0.047, BAYES_00=-2.599] Received: from smtp.gentoo.org ([127.0.0.1]) by localhost (smtp.gentoo.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id ZlDullB+viHE for ; Wed, 25 Nov 2009 21:52:18 +0000 (UTC) Received: from lo.gmane.org (lo.gmane.org [80.91.229.12]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.gentoo.org (Postfix) with ESMTP id 5BF6C67C42 for ; Wed, 25 Nov 2009 21:52:17 +0000 (UTC) Received: from list by lo.gmane.org with local (Exim 4.50) id 1NDPmW-0000Mf-KJ for gentoo-dev@gentoo.org; Wed, 25 Nov 2009 22:52:12 +0100 Received: from ip68-231-21-207.ph.ph.cox.net ([68.231.21.207]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 25 Nov 2009 22:52:12 +0100 Received: from 1i5t5.duncan by ip68-231-21-207.ph.ph.cox.net with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Wed, 25 Nov 2009 22:52:12 +0100 X-Injected-Via-Gmane: http://gmane.org/ To: gentoo-dev@lists.gentoo.org From: Duncan <1i5t5.duncan@cox.net> Subject: [gentoo-dev] Re: mtime preservation Date: Wed, 25 Nov 2009 21:52:00 +0000 (UTC) Message-ID: References: <19184.25176.380022.392451@a1i15.kph.uni-mainz.de> <20091108191439.3fcee79d@snowcone> <7c612fc60911090718y144319f5lc9827a5e2e153c2@mail.gmail.com> <20091109153429.502e272f@snowcone> <19193.4389.637969.727075@a1i15.kph.uni-mainz.de> <20091119221248.539eedd9@snowmobile> <7c612fc60911191614h5e37c849y50ad217a828fa744@mail.gmail.com> <20091120001820.7274bdf7@snowmobile> <4B07362D.2010108@gentoo.org> <7c612fc60911231049n4a51ddb0u30ae72d8ed93cdec@mail.gmail.com> <7c612fc60911251313i705a182as6cf50402c7829beb@mail.gmail.com> <20091125212718.5deb42f8@snowcone> Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-Id: Gentoo Linux mail X-BeenThere: gentoo-dev@lists.gentoo.org Reply-to: gentoo-dev@lists.gentoo.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: ip68-231-21-207.ph.ph.cox.net User-Agent: Pan/0.133 (House of Butterflies) Sender: news Content-Transfer-Encoding: quoted-printable X-Archives-Salt: ebaea1c4-c254-4a58-ada2-abb1a9ae9432 X-Archives-Hash: 1a9255c981014eda97266f9898be6ca7 Ciaran McCreesh posted on Wed, 25 Nov 2009 21:27:18 +0000 as excerpted: > Portage uses two ways of merging a file: os.rename() and the manual way= . >=20 > os.rename() correctly preserves mtimes. >=20 > Python's os.utime call, which is what Portage uses to preserve mtimes > for files that it installs the hard way, and which is not a wrapper for > the Unix utime call, uses an IEEE 754 double to handle timestamps. But = a > double only gives sixteen accurate decimal digits, and you've got ten t= o > the left of the decimal point, leaving only six reliably preserved, wit= h > the remaining three digits being corrupted. >=20 > Thus, packages can end up being installed with some files having > accurately-preserved mtimes, and some having corrupted mtimes, which > will lead to mtime comparisons giving incorrect results. That's a great explanation (thanks, I now know the details to the degree=20 I'd be interested), but what was asked for was examples of breakage, aka=20 actual bugs. I seem to remember either you or someone else mentioning=20 that there had been a couple issues already, and I'll take the claim at=20 face value, but actual bug numbers would be nice. =3D:^) --=20 Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman