From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263151AbTJEQgU (ORCPT ); Sun, 5 Oct 2003 12:36:20 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263152AbTJEQgU (ORCPT ); Sun, 5 Oct 2003 12:36:20 -0400 Received: from cpe-24-221-190-179.ca.sprintbbd.net ([24.221.190.179]:42396 "EHLO myware.akkadia.org") by vger.kernel.org with ESMTP id S263151AbTJEQgT (ORCPT ); Sun, 5 Oct 2003 12:36:19 -0400 Message-ID: <3F80484A.3030105@redhat.com> Date: Sun, 05 Oct 2003 09:35:22 -0700 From: Ulrich Drepper Organization: Red Hat, Inc. User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.5) Gecko/20030925 Thunderbird/0.3 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Krzysztof Benedyczak CC: linux-kernel@vger.kernel.org, Manfred Spraul , pwaechtler@mac.com, Michal Wronski Subject: Re: POSIX message queues References: In-Reply-To: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Krzysztof Benedyczak wrote: > There are a lot of differencies but if the most important one is use of > ioctl vs syscalls it can be changed (in fact our implementation loong time > ago used syscalls). Syscalls are always better. At least from my perspective. Just imagine how the runtime should determine that the kernel doesn't support msqs? With syscalls I get -ENOSYS back. With ioctls I get EINVAL. But what this mean? Functionality not available? Invalid parameters to the existing implementation? ALso think about strace which is an important part in many peoples life. Hiding the functionality in some ioctls doesn't make it easy to follow the program even if strace gets even more code added to the ioctl decoder. Basically, demultiplexers are bad. Syscalls are cheap. > In another words: is our implementation in the position > of NGPT or better? ;-) I don't understand. Why NGPT and what about "position"? If you mean including a solution in the runtime (librt), sure, this will happen. But not before I see a solution in the official kernel. -- --------------. ,-. 444 Castro Street Ulrich Drepper \ ,-----------------' \ Mountain View, CA 94041 USA Red Hat `--' drepper at redhat.com `---------------------------