Re: Pointer arithmetic error

[Bernd Petrovitsch <bernd@firmix.at>]

On Fre, 2008-06-27 at 11:01 -0700, Christopher Li wrote: 
> > In C, there is no type "byte" (unless you typedef oder #define it).
> > "byte" is usually (but not necessarily) meant as "unsigned char".
> 
> In C spec, there is a concept of "byte". The union return by sizeof()

I stand corrected. Hmm, I need the time to read C99 thoroughly.

> is byte. Char must fit in a byte. But char does not necessary have the
> same bits as byte. Char can have more.
> 
> C99: 3.6, 3.7.1
>
> Because char can always fit in byte, sizeof(char) == 1.

But how can a char have more bits than a byte?

> > IIRC C specifies that sizeof() returns values measured in chars, but
> > I don't believe it specifies any mapping between the size of chars
> > and the underlying addressing units --- it should be possible to use
> > 16-bit chars, for example, on an 8-bit byte system. > Using 32-bit
> > ints, sizeof(int) would then return 2; but you wouldn't be able to
> > access individual bytes from C.
> 
> sizeof() return value measure in _byte_.
> C99: 6.5.3.4

Yes. But "sizeof(char)" is always 1 (as stated in the same chapter). 
So I see no real difference between "byte" and "char" (at least with the
size of them).

	Bernd
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