From owner-cvs-all@FreeBSD.ORG Tue Jan 25 10:37:33 2005 Return-Path: Delivered-To: cvs-all@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id EB2D116A4CE; Tue, 25 Jan 2005 10:37:33 +0000 (GMT) Received: from critter.freebsd.dk (f170.freebsd.dk [212.242.86.170]) by mx1.FreeBSD.org (Postfix) with ESMTP id 3606E43D4C; Tue, 25 Jan 2005 10:37:33 +0000 (GMT) (envelope-from phk@critter.freebsd.dk) Received: from critter.freebsd.dk (localhost [127.0.0.1]) by critter.freebsd.dk (8.13.1/8.13.1) with ESMTP id j0PAbW5R080963; Tue, 25 Jan 2005 11:37:32 +0100 (CET) (envelope-from phk@critter.freebsd.dk) To: Andrey Chernov From: "Poul-Henning Kamp" In-Reply-To: Your message of "Tue, 25 Jan 2005 13:32:50 +0300." <20050125103250.GA29461@nagual.pp.ru> Date: Tue, 25 Jan 2005 11:37:32 +0100 Message-ID: <80962.1106649452@critter.freebsd.dk> Sender: phk@critter.freebsd.dk cc: cvs-src@FreeBSD.ORG cc: src-committers@FreeBSD.ORG cc: cvs-all@FreeBSD.ORG Subject: Re: cvs commit: src/sys/kern sys_generic.c X-BeenThere: cvs-all@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: CVS commit messages for the entire tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 25 Jan 2005 10:37:34 -0000 In message <20050125103250.GA29461@nagual.pp.ru>, Andrey Chernov writes: >On Tue, Jan 25, 2005 at 11:26:32AM +0100, Poul-Henning Kamp wrote: >> Show me code which breaks please. > >It is not an argument. Your commit violates both POSIX and SUSv3, namely >this thing: > >"This volume of IEEE Std 1003.1-2001 requires that no action be taken for >read() or write() when nbyte is zero. This is not intended to take >precedence over detection of errors (such as invalid buffer pointers or >file descriptors). This is consistent with the rest of this volume of IEEE >Std 1003.1-2001, but the phrasing here could be misread to require >detection of the zero case before any other errors." Notice the "require" it doesn't ban the practice. >If you read my previous message to the end, I already mention the case >which is obviously broken: FIFOs blocking and EAGAIN returning - it must >happens for zero byte reads too. Go look at fifofs: we never did that (please see also rev. 1.104 to avoid a tiresome round of "you broke this" "no I didn't"). -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 phk@FreeBSD.ORG | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence.