Re: Distributed system portability

[Thierry Lelegard <thierry.lelegard@canal-plus.fr>]

> When streams go to a file, wouldn't there be a problem with differences
> between record-oriented file systems and bag-of-bytes oriented file
> systems ?

Exactly (I know you are thinking about VMS, which we use as well).
In a file, there is the "logical content" (the data) and the physical
content (the raw content of the blocks of the file). Both are identical
on UNIX but they are not on VMS.

But, anyway, the Ada95 streams only care about the "logical content".
However, even this logical content is non standard. The very first
reason for this is the horrible "type Stream_Element is mod 
implementation-defined" in Ada.Streams. You cannot base interoperability
on an "implementation-defined" feature.

> Or is the idea of streams that one should never try to access them
> from a non-Ada language ?

Yes, for the reason above.

-Thierry
____________________________________________________________________________

Thierry Lelegard, "The Jazzing Troll", Email: thierry.lelegard@canal-plus.fr
CANAL+ Technologies, 34 place Raoul Dautry, 75906 Paris Cedex 15, France
Tel: +33 1 71 71 54 30   Fax: +33 1 71 71 52 08   Mobile: +33 6 03 00 65 75
____________________________________________________________________________