Re: Howto read line from a stream

[sjw <simon.j.wright@mac.com>]

On May 31, 5:07 pm, "Dmitry A. Kazakov" <mail...@dmitry-kazakov.de>
wrote:
> On Sun, 31 May 2009 08:38:57 -0700 (PDT), sjw wrote:
> > On May 31, 12:34 pm, "Dmitry A. Kazakov" <mail...@dmitry-kazakov.de>
> > wrote:
>
> >> One potential problem with using Streams as an interface to sockets is that
> >> there is nothing in the Ada standard that mandates Stream_Element to be an
> >> octet of bits, as socket I/O demands.
>
> > Can't imagine what reason an implementer would have to make a stream
> > element anything other than an octet! (for any general-purpose
> > processor you'd actually be likely to come across).
>
> This is a question you should better address to the designers of the Ada
> standard. For some reasons they didn't take the responsibility to mandate
> that Stream_Element'Size = 8.

Fairly strong hint, I think, in http://www.adaic.com/standards/05aarm/html/AA-13-13.html
(1).

An implementation with Stream_Element'Size /= 8 would be in a world of
its own, probably better off not to bother with a socket library!

> I am not a language lawyer, but I remember a DSP processor with
> sizeof(char)=4.

I spent a lot of time with a processor that (if it had had a C
compiler) would have had 24-bit chars.

> I suggest that it should be difficult quite there to have:
>
>    type Stream_Element_Array is
>         array(Stream_Element_Offset range <>) of aliased Stream_Element;
>
> (note *aliased*), with 8 bit Stream_Element and packed
> Stream_Element_Array.

See http://www.adaic.com/standards/05aarm/html/AA-13-13-1.html (11.c/2)