On Sun, Nov 18, 2007 at 12:27:37PM +0100, Robert Millan wrote:
> On Tue, Oct 23, 2007 at 09:06:16PM +0200, Christian Franke wrote:
> > +/* Check memory address */
> > +static int
> > +addr_is_valid (grub_addr_t addr)
> > +{
> > + volatile unsigned char * p = (volatile unsigned char *)addr;
> > + unsigned char x, y;
> > + x = *p;
> > + *p = x ^ 0xcf;
> > + y = *p;
> > + *p = x;
> > + return y == (x ^ 0xcf);
> > +}
>
> 0xff would be better IMO.
Uhm actually, I just remembered that we have the ~ operator precisely for
that :-)
--
Robert Millan
<GPLv2> I know my rights; I want my phone call!
<DRM> What use is a phone call, if you are unable to speak?
(as seen on /.)
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