From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754433AbXGaW6b (ORCPT ); Tue, 31 Jul 2007 18:58:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751542AbXGaW6Y (ORCPT ); Tue, 31 Jul 2007 18:58:24 -0400 Received: from ns1.suse.de ([195.135.220.2]:49431 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751511AbXGaW6X (ORCPT ); Tue, 31 Jul 2007 18:58:23 -0400 From: Andreas Schwab To: Matt Mackall Cc: Dave Hansen , "linux-kernel@vger.kernel.org" Subject: Re: /proc/$pid/pagemap troubles References: <1185914174.18414.184.camel@localhost> <20070731213718.GW11115@waste.org> X-Yow: Life is selling REVOLUTIONARY HAIR PRODUCTS! Date: Wed, 01 Aug 2007 00:58:21 +0200 In-Reply-To: <20070731213718.GW11115@waste.org> (Matt Mackall's message of "Tue\, 31 Jul 2007 16\:37\:18 -0500") Message-ID: User-Agent: Gnus/5.110006 (No Gnus v0.6) Emacs/22.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Matt Mackall writes: > On Tue, Jul 31, 2007 at 01:36:14PM -0700, Dave Hansen wrote: >> Since the pagemap code has a little header on it to help describe the >> format, I wrote a little c program to parse its output. I get some >> strange results. If I do this: >> >> fd = open("/proc/1/pagemap", O_RDONLY); >> count = read(fd, &endianness, 1); >> >> count will always be 4. > > Known bug, fixed in my pending and not-currently-working update. It > ought to return 0 for short reads. That's not a good choice. Returning 0 means EOF, but there is actually data to be read. Andreas. -- Andreas Schwab, SuSE Labs, schwab@suse.de SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany PGP key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5 "And now for something completely different."