Extending sbufs with a drain, take 2

[mdf at FreeBSD.org]

On Thu, Sep 9, 2010 at 1:58 PM, Poul-Henning Kamp <phk at phk.freebsd.dk> wrote:
> In message <AANLkTik7+KTOCYJiZ_n3SYTbwszNPNgh0SL49HhJDoii at mail.gmail.com>, mdf@
> FreeBSD.org writes:
>
>>One question about the printf expanded args in xprintf.c:
>>
>>Does the extension framework allow for multiple character conversion
>>specifiers?
>
> I belive it indexes with a single char into an array right now, but
> that is just a matter of string parsing, {...} is not hard to do.
>
> Bear in mind that using extensions force you to disable the GCC
> format checks, a heavy cost to bear.

Conveniently, we already have code at Isilon that modifies the gcc
format checks to look for the %{} format.  I saved an email with info
about Clang's format checks so I may be able to do something there
too.

> Also bear in mind that any work on this should keep an eye on, and if
> at all possible collaborate with GLIBC for maximum compatibility.

Yes, this is something I don't know anything about.  I'll look into it.

Thanks,
matthew