On 09/04/2013 05:02 PM, Geert Uytterhoeven wrote: > On Wed, Sep 4, 2013 at 10:09 AM, Chen Gang <gang.c...@asianux.com> wrote: >> On 09/04/2013 03:02 PM, Geert Uytterhoeven wrote: >>> On Wed, Sep 4, 2013 at 3:08 AM, Chen Gang <gang.c...@asianux.com> wrote: >>>> On 09/04/2013 12:41 AM, Geert Uytterhoeven wrote: >>>>> On Tue, Aug 6, 2013 at 3:46 AM, Chen Gang <gang.c...@asianux.com> 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 <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)? Thanks. > Gr{oetje,eeting}s, > > Geert > > -- > Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- > ge...@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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/