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Date: Wed, 7 Mar 2012 15:28:48 -0600
From: Peter Seebach <peter.seebach@windriver.com>
To: Peter Zijlstra <peterz@infradead.org>
CC: Ingo Molnar <mingo@elte.hu>, Arnaldo Carvalho de Melo <acme@redhat.com>,
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Subject: Re: [PATCH] perf: Incorrect use of snprintf results in SEGV
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On Wed, 7 Mar 2012 21:59:24 +0100
Peter Zijlstra <peterz@infradead.org> wrote:

> On Wed, 2012-03-07 at 21:37 +0100, Ingo Molnar wrote:
> >         size_needed = snprintf_size(...);
> 
> This would require 3 passes over the fmt+args, first to find the
> allocated size is insufficient, 2nd to compute the size, 3rd to fill
> buffer.
> 
> Whereas with the current "creative" API only 2 passes are needed.
> 
> I can imagine that back in the day of small memory and small CPU this
> was deemed important enough.

It occurs to me that I have seen this discussion, or a variant, before:

http://coding.derkeiler.com/Archive/C_CPP/comp.lang.c/2004-11/2332.html

In which people discuss the possible alternative return values at some
length.

-s
-- 
Listen, get this.  Nobody with a good compiler needs to be justified.