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.c...@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 -- >> 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/