From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762256Ab3IDJOn (ORCPT ); Wed, 4 Sep 2013 05:14:43 -0400 Received: from intranet.asianux.com ([58.214.24.6]:49466 "EHLO intranet.asianux.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756051Ab3IDJOm (ORCPT ); Wed, 4 Sep 2013 05:14:42 -0400 X-Spam-Score: -100.9 Message-ID: <5226F9BF.8040304@asianux.com> Date: Wed, 04 Sep 2013 17:13:35 +0800 From: Chen Gang User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130110 Thunderbird/17.0.2 MIME-Version: 1.0 To: Geert Uytterhoeven CC: Jiri Kosina , Paul McKenney , "dhowells@redhat.com" , Thomas Gleixner , Dave Jones , Arnd Bergmann , David Miller , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH trivial] UAPI: Kbuild: add/modify comments for "uapi/Kbuild" and "uapi/linux/Kbuild" References: <52005571.4080704@asianux.com> <52268800.2010200@asianux.com> <5226EAAE.6090500@asianux.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/04/2013 05:02 PM, Geert Uytterhoeven wrote: > On Wed, Sep 4, 2013 at 10:09 AM, Chen Gang wrote: >> On 09/04/2013 03:02 PM, Geert Uytterhoeven wrote: >>> On Wed, Sep 4, 2013 at 3:08 AM, Chen Gang wrote: >>>> On 09/04/2013 12:41 AM, Geert Uytterhoeven wrote: >>>>> On Tue, Aug 6, 2013 at 3:46 AM, Chen Gang wrote: >>>>>> --- a/include/uapi/Kbuild >>>>>> +++ b/include/uapi/Kbuild >>>>>> @@ -1,7 +1,6 @@ >>>>>> # UAPI Header export list >>>>>> -# Top-level Makefile calls into asm-$(ARCH) >>>>>> -# List only non-arch directories below >>>>>> - >>>>>> +# Except "linux/", UAPI means Universal API. >>>>> >>>>> Sorry for my silly question, but what's the purpose of this "Universal >>>>> API" comment? >>>>> >>>> >>>> Firstly, at least for me, I don't think it is a silly question (maybe >>>> it means I should give additional explanations). :-) >>>> >>>> I 'guess' the "Universal API" means: >>>> >>>> "the API which can be used under multiple OS (independent from Linux), it may be used under kernel mode or user mode". >>>> >>>> It is just my 'guess', welcome additional suggestions or completions by >>>> any members. >>>> >>>> When we get this correct additional explanation after discussing, if >>>> suitable, I should add the final explanation to current patch. >>> >>> Thanks. As this is not related at all to Linux, I don't see a reason >>> to add this comment. >>> >>> Here, "UAPI" means "userspace API" only. >> >> Hmm... why we need "uapi/linux/" ? (I can not find some related >> documents, so I have to 'guess'). > > The "uapi" subdirectories are there to distinguish userspace headers from > kernelspace headers, and allow both to live in the kernel source tree. > > When running "make headers_install", the (processed) headers in the > various "uapi" subdirectories are copied to /usr/include. > Hence "uapi/linux/foo.h" becomes in userspace. > In userspace there are no "uapi" subdirectories anymore. > Yeah, so why need another "uapi/*" excluding "uapi/linux" ? Are they also truly still "Userspace API" but which need not distinguish ? (at least, it seems that idea is not quite good). Hmm... maybe the "uapi/*" except "uapi/linux" are also installed? Is it for compatible (originally they are here, and now we have to follow, it is no reason to change if not find related critical issues)? Thanks. > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org > > In personal conversations with technical people, I call myself a hacker. But > when I'm talking to journalists I just say "programmer" or something like that. > -- Linus Torvalds > > -- Chen Gang