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Date: Thu, 1 Oct 2009 10:55:56 +0200
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Subject: Re: [PATCH 1/9] lib/vsprintf.c: Add %pU to print UUID/GUIDs
From: Geert Uytterhoeven <geert@linux-m68k.org>
To: Joe Perches <joe@perches.com>
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On Thu, Oct 1, 2009 at 09:26, Joe Perches <joe@perches.com> wrote:
> On Thu, 2009-10-01 at 09:10 +0200, Geert Uytterhoeven wrote:
>> > Standardize the printed style of UUID/GUIDs by using
>> > another extension to %p.
>> >
>> > %pU:    01020304-0506-0708-090a-0b0c0d0e0f10
>> > %pUr:   04030201-0605-0807-090a-0b0c0d0e0f10
>> > %pU[r]X:Use upper case hex
>>
>> To me, it looks a bit strange to have the options after the `U', combined with
>> the variable-length nature.
>
> I think the whole %p<foo> mechanism is strange and takes
> a bit of getting used to.
>
> You're free to suggest alternatives.
>
> Keep in mind expansion for future different types and that
> <foo> must be alphanumeric chars only.

`r' is reverse endianness?

So what about
    %pUb: lower case big endian
    %pUl: lower case little endian
    %pUB: upper case big endian
    %pUL: upper case little endian
?

That way it's fixed length, and easier to parse.

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