Re: Why no socket package in the standard ?

[Maciej Sobczak <see.my.homepage@gmail.com>]

On 24 Maj, 09:25, "Dmitry A. Kazakov" <mail...@dmitry-kazakov.de>
wrote:

> > In the language? Probably none, as this does not belong to the
> > language.
>
> That is an interesting question. Actually sockets could belong to the
> language. Consider for example the select statement containing alternatives
> of a socket's select.

Still, they (sockets) don't have to be part of the language to be
select-ready. It is enough to make them protected objects with
appropriate entries.
The problem is, neither Ada nor the operating system make it easy to
do this kind of integration in a sufficiently efficient way.

Which brings some interesting point for the future language evolution:
make it possible to write "select hooks" - that is, protected
procedures that are called automatically when any task attempts to
call some entry in any way, including its use in the select statement.
Something like:

protected Example is
   entry Lets_Go when Ready is ...

   -- this procedure is called when Lets_Go is used
   -- it is executed *before* evaluation of the barrier in Lets_Go
   procedure Lets_Go_Hook is
   begin
      -- ...
      -- perhaps set Ready or whatever
   end Lets_Go_Hook;

private
   Ready : Boolean;
end Example;

With this language feature I can imagine a relatively efficient
implementation of a socket library where socket objects are selectable
in the Ada sense.

Nitpick: implement Ada 2005 before that. Please. ;-)

> > It might, however, be part of the standard library.
>
> There are many difficulties on that path. When people are demanding sockets
> they forget that beyond TCP/IP and UDP there is a lot of other stuff
> communicated over sockets, e.g. multi-cast protocols, raw sockets and so
> on. These are barely standardized.

So what? Standardize the stuff that is obvious to standardize and
don't throw the baby out with the water. Just don't give people more
reasons for not learning Ada.

--
Maciej Sobczak * http://www.msobczak.com * http://www.inspirel.com