Re: Ada Tutor Web Site Shutting Down

[Rugxulo <rugxulo@gmail.com>]

Hi,

On May 5, 4:12 pm, "Randy Brukardt" <ra...@rrsoftware.com> wrote:
>
> Better, dunno. Janus/Ada 95 (32-bit only) would be updated if anyone wanted
> it, but no one has asked. (It's still in our pricelists.)

Updated how? (A quick glance at the 2005 standard seems more
complicated regarding changes than initially implied.) Well, I'm not a
customer (and don't know Ada), so I guess that rules me out.  ;-)
I'd assume it's "good enough" for the few that use DOS commercially
these days. (I assume you probably are more geared towards businesses
than home users.)

The only significant DOS Ada app I know of (which is probably my
fault, not Ada's) is Gautier's 3D engine (used GNAT):
http://sites.google.com/site/rugxulo/eng3d018.zip?attredirects=0

> But a better question is why would you want to use a new compiler?

Why not?  :-)  No, seriously, I was only responding to the OP's claim
that Ada95 is obsolete and that his tutorial was in DOS (hence, old)
and needed to be updated. I don't even know what compiler he used for
it originally.

> Is there anything inportant that you can do in DOS that you can't do
> in a Windows console program or a standard Linux program?

Sure, run in DOS!  :-))

(self-modifying code? direct hardware access? run in less than 10 MB
of RAM? call the BIOS?)

> The main reason for compiling a
> DOS program would be so that you don't have to change anything about,
> including the DOS specific stuff.

Sure, assuming there is any DOS-specific stuff, which I know is
sometimes unavoidable, but doing that almost defeats the purpose of a
portable HLL.

> In that case, you're best off sticking
> with the same compiler that it was built with, why make more work by
> introducing a new set of bugs.

Well, bugs will always exist, even with the best of intentions and
strictest preparations.

> (We occassionally get requests for absolutely ancient compiler versions, for
> someone that needs to make a tiny change in some old program. Not long ago,
> I needed to dig up a 1985 version of Janus/Ada for someone. The cool thing
> was that I tried running it to make sure I'd copied it uncorrupted [an issue
> because it copied from 25 year old floppies], and it worked fine on a modern
> Windows XP machine. I knew there was a reason that we were really careful
> about following the OS rules back in the day...)

Yes, that's the ideal, software that still runs for many years in the
future. The DPMI standard helped that a lot. For sure, DOS lived a
long, long time.

Unfortunately, Windows has gone downhill (in DOS support) since XP,
and 64-bit completely kills it. (XP Mode is only for business
editions, not home users.) You'll have to use DOSBox or VirtualBox
(preferably with VT-X) or else switch to Linux for DOSEMU. (Well, you
could run FreeDOS natively, but I doubt most will consider that.)