Re: [PATCH trivial] UAPI: Kbuild: add/modify comments for "uapi/Kbuild" and "uapi/linux/Kbuild"

[Chen Gang <gang.chen@asianux.com>]

On 09/04/2013 05:38 PM, Chen Gang wrote:
> On 09/04/2013 05:27 PM, Geert Uytterhoeven wrote:
>> On Wed, Sep 4, 2013 at 11:13 AM, Chen Gang <gang.chen@asianux.com> wrote:
>>>>> 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 <linux/foo.h> 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)?
>>
>> All uapi files are installed, a.o. /usr/include/scsi/, /usr/include/video/, ...
>>
> 
> Oh, sorry, I misunderstand your original mail contents.
> 
>> Historically, everything under "include" in the kernel source tree was
>> installed in /usr/include/, after (semi)manual cleanup.
>> Since the uapi split, everything is handled automatically.
>> Because of compatibility reasons (do not break userspace), paths had to
>> stay the same.
>>
> 
> At least for me, that sounds reasonable.
> 
> Hmm... when some members need add a new Userspace API. I guess:
> 
>   if it is related with one of existent "uapi/*" sub-directory (except "uapi/linux"), they need put the file(or directory) under the related "uapi/*",
> 
>   if can not find existent "uapi/*" sub-directory, they need put the file(or directory) under "uapi/linux/*".
> 

Hmm... if "uapi/*" are really only for compatible, better to keep them
no touch, that means: should always add new file(or directory) under
"uapi/linux/" sub-directory (even if they are related with "uapi/*").


Thanks.

> Does it sound reasonable ?
> 
> 
> 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