From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262890AbTEGGOF (ORCPT ); Wed, 7 May 2003 02:14:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262894AbTEGGOF (ORCPT ); Wed, 7 May 2003 02:14:05 -0400 Received: from pizda.ninka.net ([216.101.162.242]:44525 "EHLO pizda.ninka.net") by vger.kernel.org with ESMTP id S262890AbTEGGOD (ORCPT ); Wed, 7 May 2003 02:14:03 -0400 Date: Tue, 06 May 2003 22:19:00 -0700 (PDT) Message-Id: <20030506.221900.38693097.davem@redhat.com> To: hch@infradead.org Cc: dwmw2@infradead.org, thomas@horsten.com, linux-kernel@vger.kernel.org Subject: Re: [PATCH] 2.4.21-rc1: byteorder.h breaks with __STRICT_ANSI__ defined (trivial) From: "David S. Miller" In-Reply-To: <20030507072002.A7424@infradead.org> References: <20030507062613.A5318@infradead.org> <20030506.220714.35679546.davem@redhat.com> <20030507072002.A7424@infradead.org> X-FalunGong: Information control. X-Mailer: Mew version 2.1 on Emacs 21.1 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 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 From: Christoph Hellwig Date: Wed, 7 May 2003 07:20:02 +0100 On Tue, May 06, 2003 at 10:07:14PM -0700, David S. Miller wrote: > For example, I just changed the values of a few SADB_EALG_* values in > pfkeyv2.h. Now ipsec-tools is effectively broken. Oops, when will > the copy in ipsec-tools get updated? You just broke the userland ABI which must not happen. at all. That's why userland having older headers is fine. Wrong, the ABI in the 2.5.x IPSEC stuff is not cast in stone yet. What about if I extend stuff without breaking the ABI? How do apps get at the new features? That's why we want the glibc-kernheader package. Or even better a package of headers that can be used by the kernel and userland, but this would require people to properly sort out kernel header functionality like internal structures and prototypes/inlines from the actual ABI-relevant contents. The networking headers currently are very bad on this. Yes, this is one way to deal with it. Actually, if you look, things like include/linux/xfrm.h are excellent examples of userland compatible kernel headers :-)