On Wed, Jun 3, 2009 at 1:11 AM, Isaac Marino Bavaresco <
isaacbavaresco@yahoo.com.br> wrote:

> > These things are perfect if you are always use pointers to byte size
> types
> > (like char for example). In C the +n means +n*sizeof(m). For example if
> you
> > have a pointer to int32 to mem location 100 and want to address of the
> 4th
> > element in the array, you say *m+n = *100+(4*4) = 116. Now if you say
> *n+m =
> > *4+100 it is only 104 or if you say *4+(4*100) then again that's wrong.
> >
> > Tamas
> >
>
> No, not true. The compiler knows the size of the object pointed to by
> the pointer and scales the index so you access the correct element.
>
> long *p, n;
> n = *(p+10) // Accesses the 11th element of the array, not the middle of
> the 3rd element.
>

Yep, I know this. What I was confused was about n = *(10+p) -- I thought the
compiler gets the number 10, treats as an integer and silently converts as a
pointer and then gets the p and casts as an integer and as a results overall
messes up the size. But now it is clear. What is more confusing is n = 10[p]
which is still correctly calculated.

Thanks,
Tamas
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