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Re: [RFC] strcpy optimizations

From: Petr Baudis <pasky at ucw dot cz>
To: Ondřej Bílka <neleai at seznam dot cz>
Cc: Paul Eggert <eggert at cs dot ucla dot edu>, andi at firstfloor dot org,libc-alpha at sourceware dot org
Date: Wed, 30 Jan 2013 14:33:41 +0100
Subject: Re: [RFC] strcpy optimizations
References: <20130129201542.GA23023@domone.kolej.mff.cuni.cz><51083F61.4070103@cs.ucla.edu><20130130122613.GD18195@machine.or.cz><20130130124955.GA22691@domone.kolej.mff.cuni.cz>

On Wed, Jan 30, 2013 at 01:49:56PM +0100, Ondřej Bílka wrote:
> On Wed, Jan 30, 2013 at 01:26:14PM +0100, Petr Baudis wrote:
> > On Tue, Jan 29, 2013 at 01:30:09PM -0800, Paul Eggert wrote:
> > > strncpy should be lower priority, I'd say.  Typically, a program
> > > that uses strncpy doesn't care all that much about performance.
> > 
> > That seems a most intriguing insight to me. Why would that be so?
> >
> Because of c standard strncpy must zero remaining bytes upto n. 
> 
> This is problematic, for example when we set strncpy breakpoint in gimp
> then first entry is:
> 
> strncpy (x=0x7fffffffc3a0 "@P[\366\377\177", y=0x7ffff2a0961f "/usr/share/X11/locale", n=4096)

Right! I'm stupid, somehow I was thinking strncmp in my head...

Sorry for the noise,

				Petr "Pasky" Baudis

References:
- [RFC] strcpy optimizations
  - From: OndÅej BÃlka
- Re: [RFC] strcpy optimizations
  - From: Paul Eggert
- Re: [RFC] strcpy optimizations
  - From: Petr Baudis
- Re: [RFC] strcpy optimizations
  - From: OndÅej BÃlka

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