Ada Stuff and some confusion

Ada Stuff and some confusion

[chris.danx]

Hi,
    I am writing some Ada examples for my new web page.  It will consist of
a few examples of things I've found difficult in the past and which a lot of
people in this group have helped me with.  (Thanks to all again).  Things
like Streams for file IO, modular type usage, exception handling, and tons
more I've learned from you guys.

Now I need you're help again with a general programming question.  I'm
confused as to the difference between 'declaration' and 'definition'.  I
remember reading somewhere that many computer programmers don't know or
confuse them.  I also don't want to put up inaccurate stuff up on the web,
and proliferate the wrong definitions and add to the situation.

I also want to know about my Ada sources and licensing.  I use GNAT at the
minute (I don't expect this to change until I win the lottery, and even then
I doubt I'll change.  It's the best compiler I've used, ever!).  My question
is to do with GPL.  I don't really understand it.  I think it means that any
software I write with it must also be GPL'ed (or LGPL'ed).  Now I have two
questions about this.  Can I just put a comment in the source, at the top in
flashing lights, "this source is licensed under GPL, see license.txt for
further details" or do I have to include the license in the source.

My second question is can I ditch the license and go with my own.  I don't
really have a problem with making it GPL'ed, but i do find the license too
wordy in a technical sense.

What about this?


THESE SOURCES ARE PROVIDED AS IS ON THE UNDERSTANDING THAT THE AUTHOR IS NOT
RESPONSIBLE FOR ANY CONSEQUENCES DIRECTLY OR UNDIRECTLY FROM THE USE OF THIS
SOFTWARE.

THE AUTHOR GIVES HIS OR HER PERMISSION THAT THESE SOURCES MAY BE ALTERED
PROVIDING ALL CHANGES ARE CLEARLY MARKED AND ATTRIBUTED TO THE PERSON WHO
MADE THOSE CHANGES.  THE AUTHOR OF THOSE CHANGES MUST AGREE TO THIS LICENSE
AND SHOULD NOT ALTER THE LICENSE IN ANY WAY.

THIS SOFTWARE IS NOT MEANT FOR USE IN A SAFETY CRITICAL SYSTEM OR ANY SYSTEM
REQUIRING ASSURANCES OF SOFTWARE RELIABILITY.

IF YOU DO NOT AGREE TO THESE CONDITIONS DO NOT USE THIS SOFTWARE.  IF YOU
VIOLATE ANY OF THESE CONDITIONS THE AUTHOR RESERVES THE RITE TO TAKE ACTION
AGAINST YOU IN ACCORDANCE WITH THE LAWS OF YOUR COUNTRY SHOULD THE AUTHORS
NAME BE BROUGHT INTO DISREPUTE THROUGH YOUR ACTIONS.

THE AUTHOR DISTRIBUTES THESE SOURCES IN THE HOPE THEY MAY BE USEFUL.


This is just off the top of my head.  Sounds GPLish but clearer i think.
What do you think?  I'm going to have to change it slightly or make a second
version for OS writing i think.  Don't know if this would be legally
binding.


Thanks,
Chris Campbell

Re: Ada Stuff and some confusion

[Marin David Condic]

1: Good luck with your web page. (You ought to post the URL). One thing to
attempt to do with your programming examples is to keep them as simple and
focused as possible. Try to illustrate only one thing at a time - although
sometimes it is not easy to do. Keep the illustrations as a single,
compilable, executable main program wherever possible. You want your
audience to see how a specific feature is used & be able to play around with
it by making their own modifications & recompiling, etc.

2: Declaration vs Definition: From the ARM, apendix N:

Definition. All declarations contain a definition for a view of an entity. A
view consists of an identification of the entity (the entity of the view),
plus view-specific characteristics that affect the use of the entity through
that view (such as mode of access to an object, formal parameter names and
defaults for a subprogram, or visibility to components of a type). In most
cases, a declaration also contains the definition for the entity itself (a
renaming_declaration is an example of a declaration that does not define a
new entity, but instead defines a view of an existing entity, See section
8.5 Renaming Declarations.

In other words, a Definition lays out what a thing looks like - a
Declaration is what actually makes the thing come into existance. (Sort of
like the difference between saying "Light: a particle/wave that moves at
186000mps..." and "Let There Be Light!")

GNAT/GPL: You really need a lawyer for this one - otherwise someone could
get accused of dispensing legal advice without a license. :-) Basically,
there are a few things which should be pretty clear: First, you can use GNAT
to develop proprietary software if you like. There's nothing in the license
to stop you from building software of any sort to be used under any
conditions you like. So you don't have to GPL or LGPL anything if you don't
want to.

As for the rest - you really need to consult a lawyer about what is legally
binding, etc. You can ditch the GPL and use anything you like. Just be
advised that a man who represents himself has a fool for a client. :-)

Just an observation: Hypothetically speaking, if one were to put source code
out on the Internet & put extremely severe restrictions on it (Like "I give
you absolutely no permission whatsoever to use this software or even to look
at it!!!"), you would probably be able to count on a few things: First,
people will take it and use it anyway. (Hmmmmm... Someone violating
copyright restrictions on the Internet? What are the odds of *that*
happening???) What? You're going to spend all your time trying to catch
people who took your source code & sue them? You'd probably lose for having
created an "attractive nuisance" or something like that. Besides there isn't
likely to be any money in it. Second: If someone *were* to use your software
and - hard as it may be to believe - there was a bug in it that caused their
weapon system to explode or something equally as disasterous, would they be
able to sue you for having expressed or implied some kind of warranty or
fitness for a given purpose? They'd have to first admit to having stolen
your code & used it without your consent. If I were the judge, that would be
cause for having them (and their lawyers) spanked publically in my court for
extreme stupidity.

Now if you really *want* to have people take some major system you wrote &
utilize it, then probably GPL/LGPL or some similar license is necessary.
(Are you going to build "Ada-ix" - The Great American Operating System?
Cool!) In that case, you could either a) get a lawyer to 'splain it up to
you or b) just do what all the other guys did and rest asured that if you
get in trouble for it, you won't be the only one.

Hope this helps.

MDC
--
Marin David Condic
Senior Software Engineer
Pace Micro Technology Americas    www.pacemicro.com
Enabling the digital revolution
e-Mail:    marin.condic@pacemicro.com
Web:      http://www.mcondic.com/


"chris.danx" <chris.danx@ntlworld.com> wrote in message
news:nh0z6.4622$%W5.458504@news6-win.server.ntlworld.com...
> Hi,
>     I am writing some Ada examples for my new web page.  It will consist
of
> a few examples of things I've found difficult in the past and which a lot
of
> people in this group have helped me with.  (Thanks to all again).  Things
> like Streams for file IO, modular type usage, exception handling, and tons
> more I've learned from you guys.
>
> Now I need you're help again with a general programming question.  I'm
> confused as to the difference between 'declaration' and 'definition'.  I
> remember reading somewhere that many computer programmers don't know or
> confuse them.  I also don't want to put up inaccurate stuff up on the web,
> and proliferate the wrong definitions and add to the situation.
>
> I also want to know about my Ada sources and licensing.  I use GNAT at the
> minute (I don't expect this to change until I win the lottery, and even
then
> I doubt I'll change.  It's the best compiler I've used, ever!).  My
question
> is to do with GPL.  I don't really understand it.  I think it means that
any
> software I write with it must also be GPL'ed (or LGPL'ed).  Now I have two
> questions about this.  Can I just put a comment in the source, at the top
in
> flashing lights, "this source is licensed under GPL, see license.txt for
> further details" or do I have to include the license in the source.
>
> My second question is can I ditch the license and go with my own.  I don't
> really have a problem with making it GPL'ed, but i do find the license too
> wordy in a technical sense.
>
> What about this?
>
>
> THESE SOURCES ARE PROVIDED AS IS ON THE UNDERSTANDING THAT THE AUTHOR IS
NOT
> RESPONSIBLE FOR ANY CONSEQUENCES DIRECTLY OR UNDIRECTLY FROM THE USE OF
THIS
> SOFTWARE.
>
> THE AUTHOR GIVES HIS OR HER PERMISSION THAT THESE SOURCES MAY BE ALTERED
> PROVIDING ALL CHANGES ARE CLEARLY MARKED AND ATTRIBUTED TO THE PERSON WHO
> MADE THOSE CHANGES.  THE AUTHOR OF THOSE CHANGES MUST AGREE TO THIS
LICENSE
> AND SHOULD NOT ALTER THE LICENSE IN ANY WAY.
>
> THIS SOFTWARE IS NOT MEANT FOR USE IN A SAFETY CRITICAL SYSTEM OR ANY
SYSTEM
> REQUIRING ASSURANCES OF SOFTWARE RELIABILITY.
>
> IF YOU DO NOT AGREE TO THESE CONDITIONS DO NOT USE THIS SOFTWARE.  IF YOU
> VIOLATE ANY OF THESE CONDITIONS THE AUTHOR RESERVES THE RITE TO TAKE
ACTION
> AGAINST YOU IN ACCORDANCE WITH THE LAWS OF YOUR COUNTRY SHOULD THE AUTHORS
> NAME BE BROUGHT INTO DISREPUTE THROUGH YOUR ACTIONS.
>
> THE AUTHOR DISTRIBUTES THESE SOURCES IN THE HOPE THEY MAY BE USEFUL.
>
>
> This is just off the top of my head.  Sounds GPLish but clearer i think.
> What do you think?  I'm going to have to change it slightly or make a
second
> version for OS writing i think.  Don't know if this would be legally
> binding.
>
>
> Thanks,
> Chris Campbell
>
>

Re: Ada Stuff and some confusion

[Smark]

Chris,

You did not use GNAT to write your source code.  The fact that you use it
to compile has no effect on whatever license you choose for your source code.
I think GPL only applies if you are including GPL'd material in your
product.  I am confused though, as to whether GPL applies to object files
produced by GNAT, particularly if you have GNAT specific stuff in your code
... can anyone shed some light on this?

Mark

Re: Ada Stuff and some confusion

[Marin David Condic]

The reason that GNAT uses the LGPL is so that you can include the GNAT
runtime in your program without automatically having it fall under the GPL.
It was realized that a method must exist for people to create non-GPL
software using a GPL product like GNAT, so a different license was invented.

MDC
--
Marin David Condic
Senior Software Engineer
Pace Micro Technology Americas    www.pacemicro.com
Enabling the digital revolution
e-Mail:    marin.condic@pacemicro.com
Web:      http://www.mcondic.com/


"Smark" <not.provided@all.com> wrote in message
news:9ai9fa$j837@cui1.lmms.lmco.com...
> Chris,
>
> You did not use GNAT to write your source code.  The fact that you use it
> to compile has no effect on whatever license you choose for your source
code.
> I think GPL only applies if you are including GPL'd material in your
> product.  I am confused though, as to whether GPL applies to object files
> produced by GNAT, particularly if you have GNAT specific stuff in your
code
> ... can anyone shed some light on this?
>
> Mark
>
>
>
>

Re: Ada Stuff and some confusion

[chris.danx]

"Marin David Condic" <marin.condic.auntie.spam@pacemicro.com> wrote in
message news:9ai8dp$cm2$1@nh.pace.co.uk...
> 1: Good luck with your web page. (You ought to post the URL).

Ok here it is! http://willow.os-4u.com
I hope when i get things working some folks who hang out here can take a
peep and make sure i'm dishing out the right advice.  I wouldn't want to say
do it like this, and get it completely wrong.

>One thing to
> attempt to do with your programming examples is to keep them as simple >
and
> focused as possible. Try to illustrate only one thing at a time - although
> sometimes it is not easy to do.

It's not is it.  I want to explain things as clearly as possible and I want
to cater for people who maybe can program a little, but

> Keep the illustrations as a single,
> compilable, executable main program wherever possible. You want your
> audience to see how a specific feature is used & be able to play around
with
> it by making their own modifications & recompiling, etc.

Interaction of sorts.  This is how i learned to program first time round
(Turbo Pascal) and it's the best IMO.  Some tutorials just blast you with
info and don't stop until they've covered everything from procedures to
recursion to tasks .  Then it's go write a "Hello world" program.  Very
helpful!

Oh, that reminds me!  I'm also going to do somethings on recursion, which i
still find a little confusing.  I can do primitive recursion but I don't
have a clue about tail recursion.  I don't even know if you can do it in Ada
95.



> In other words, a Definition lays out what a thing looks like - a
> Declaration is what actually makes the thing come into existance. (Sort of
> like the difference between saying "Light: a particle/wave that moves at
> 186000mps..." and "Let There Be Light!")
>

You mean this is a definition?

    type x is record
        ....
    end record;

And this is a declaration

    a : x;

what about     type x is private?


> First, you can use GNAT to develop proprietary software if you like.

I'm not interested in proprietary software development , just now. I'd feel
bad if i was, this is just me.  Using something free and open source to do
proprietary software would make me feel bad if i didn't make it OS.  I might
consider it in the future making the sources available.

> There's nothing in the license
> to stop you from building software of any sort to be used under any
> conditions you like. So you don't have to GPL or LGPL anything if you
don't
> want to.

That's good to know!

> Just be advised that a man who represents himself has a fool for a
client.:-)

Don't understand this, what do you mean?



> Now if you really *want* to have people take some major system you wrote &
> utilize it, then probably GPL/LGPL or some similar license is necessary.

Do you think this license is similar to GPL?  I think so except it does not
have the clause any derived works must be GPL.

> (Are you going to build "Ada-ix" - The Great American Operating System?

Are you being serious.  It wasn't clear for me from the context.  I have all
sorts of problems with English and Context.  Give me Ada anyday! <g>

If you were maybe i'll drop the American bit.  I don't want to offend any
Americans cos' they seem like a friendly enough folk (if you're not China).
Sweeping generalisation coming next, be warned.  They seem very confident
and at times arrogant, well the American politicians do.  Also very
partiotic, which isn't a bad thing unless you go too far.  The truth is if
we dropped a squad of ten Glaswegian Grannies from the Gorbals or Rukazie in
the ring with any army in the world(American, Chinese, French, well just
anyone), they army would s**te a brick and build a mansion. <g>

I hope no Americans take offence at this, it's not meant to be offensive.
Confidence and Patriotism are fine qualities so long as you don't go OTT,
which some American politicians seem to do.  Also film makers tend to
portray Americans as the good guys and everyone else as the baddies or
completely useless ("whoo hoo America saves the world from alien invaders
with no help"! you get the idea!) If you've got a problem take it up with
Hollywood.

Anyways ... the reason i'm dropping it is that i want to it to appeal to
everyone not just Americans.  Seems fair.

I wan't to do an OS that's reliable and doesn't suffer from C-Pointer-itus
which is what most of my C code suffers from.  All that pointer to char
stuff for strings is what get's me everytime.  Plus C isn't really
standardized, no matter what folk tell you!

I had a problem with my website initially.  It worked fine on my machine
(wintel) but when i uploaded it to the server it went crazy.  It put someone
elses stuff in one of my frames.  You'll never guess why!

Windies, yep the M$ OS everyone loves and adores.  It accepts "\" in place
of "/"(which is the standard).  Because the server doesn't understand it, it
does funny things.  I didn't know any better, but i know now!

Why am i telling you this?  It just show's you what can happen when you
don't follow standards.  And, it's another good reason to develop a desent
OS.

There's nothing wrong with innovation but when you do daft things people are
gonna suffer.


Regards and Thanks,
Chris Campbell
http://willow.os-4u.com

p.s. You wanna know "who shot phil" then ask lisa she knows!

Re: Ada Stuff and some confusion

[Marin David Condic]

"chris.danx" <chris.danx@ntlworld.com> wrote in message
news:BW3z6.4644$bL6.871904@news2-win.server.ntlworld.com...
>
> You mean this is a definition?
>
>     type x is record
>         ....
>     end record;
>
> And this is a declaration
>
>     a : x;
>
No, not correct. Although that is the way it would seem intuitively. Check
out some of the syntax charts (BNF Notation) in the ARM - especially for
things like a type declaration or procedure declaration. You'll notice that
they say things like <something_definition>; <-(Note the semicolon here!!!)
The definition comes first (explaining the pattern, if you will) then the
semicolon makes it a declaration. One of the reasons the two things are
separated is because a definition may appear in more places than a
declaration can.


> > Just be advised that a man who represents himself has a fool for a
> client.:-)
>
> Don't understand this, what do you mean?
>
An old saying among lawyers - words to the effect of "A lawyer who defends
himself has a fool for a client". The reason being that no matter how smart
a lawyer may be or how skilled he may be, with his own case, he cannot be
dispassionate, rational and objective. Hence, he is a fool to try to defend
himself. When applied to the layman attempting to practice law on his own
behalf, it adds even more meaning. Just because you're smart and watched
lots of cop/lawyer shows on TV, doesn't mean you can defend yourself in
court. Its a specialization and you don't have the knowledge to do a good
job of it.

Of course, one needs also to consider the source... ;-)


> > (Are you going to build "Ada-ix" - The Great American Operating System?
>
> Are you being serious.  It wasn't clear for me from the context.  I have
all
> sorts of problems with English and Context.  Give me Ada anyday! <g>
>
I was playing off of "Unix". (Also off of an Americanism about retiring to
write "The Great American Novel" - like Mobey Dick.) Not entirely without
some seriousness in there. If you're looking for a name, I'd shoot for
something a little sexier and different.

If you are interested in writing an OS in Ada, maybe you want to look at:
http://www.adaos.org/ and drop Nick Roberts a line. An OS is a big thing
that could take years to do - you'll probably want some help! :-) I've not
seen much in the way of activity here in a while.

>
> I wan't to do an OS that's reliable and doesn't suffer from C-Pointer-itus
> which is what most of my C code suffers from.  All that pointer to char
> stuff for strings is what get's me everytime.  Plus C isn't really
> standardized, no matter what folk tell you!
>
Better you should contribute to an ongoing effort than start something like
this yourself. You're talking about a *LOT* of code and you'd benefit from
the knowledge others can bring to the table.

If AdaOS looked like it was going to have a solid realtime, embedded subset
kernel, I'd be interested myself. (Poverty of Time!!!) I even know of a
specific app that is *dying* for a good quality realtime OS and the market
is wide open. But they seem to be shooting for something more along the
lines of a WinNT replacement & that's not my interest.

MDC
--
Marin David Condic
Senior Software Engineer
Pace Micro Technology Americas    www.pacemicro.com
Enabling the digital revolution
e-Mail:    marin.condic@pacemicro.com
Web:      http://www.mcondic.com/

Re: Ada Stuff and some confusion

[Mark Lundquist]

Marin David Condic <marin.condic.auntie.spam@pacemicro.com> wrote in message
news:9ailip$gtr$1@nh.pace.co.uk...

> > > Just be advised that a man who represents himself has a fool for a
> > client.:-)

Kind of like, "I had a lousy guitar teacher: I was self-taught!" :-) :-)
-- mark

Re: Ada Stuff and some confusion

[Marin David Condic]

"Mark Lundquist" <mark@rational.com> wrote in message
news:Ea5z6.679813$U46.21074833@news1.sttls1.wa.home.com...
>
> Marin David Condic <marin.condic.auntie.spam@pacemicro.com> wrote in
message
> news:9ailip$gtr$1@nh.pace.co.uk...
>
> > > > Just be advised that a man who represents himself has a fool for a
> > > client.:-)
>
> Kind of like, "I had a lousy guitar teacher: I was self-taught!" :-) :-)
> -- mark
>

So *THAT's* why I play such a lousy guitar! And all these years I thought it
was because I was a poor student! :-)

MDC
--
Marin David Condic
Senior Software Engineer
Pace Micro Technology Americas    www.pacemicro.com
Enabling the digital revolution
e-Mail:    marin.condic@pacemicro.com
Web:      http://www.mcondic.com/

Re: Ada Stuff and some confusion

[chris.danx]

Hi,

> I was playing off of "Unix". (Also off of an Americanism about retiring to
> write "The Great American Novel" - like Mobey Dick.) Not entirely without
> some seriousness in there. If you're looking for a name, I'd shoot for
> something a little sexier and different.

Funnyly we are looking for a name.  Hermann, my OS development partner,
suggested ARES and I went with it assuming it didn't have any nastyness
attached.  As the folk at alt.os.development pointed out it looks like ARSE.
I'm kinda embarrased; I'm Scottish and we're usually quick to spot things
like this.  Just Scottish humour i guess!

We're setting up a vote on the name.  I put 5 names in, Hermann does the
same, and we let the internet community decide.  It's not up yet, but
Hermann will put it up soon.  I wanted to call it Birdy, cos' it's my
cousins nickname and she's great fun and completely bonkers.  Sounds good
too.

> If you are interested in writing an OS in Ada, maybe you want to look at:
> http://www.adaos.org/ and drop Nick Roberts a line. An OS is a big thing
> that could take years to do - you'll probably want some help! :-) I've not
> seen much in the way of activity here in a while.
>
> >
> > I wan't to do an OS that's reliable and doesn't suffer from
C-Pointer-itus
> > which is what most of my C code suffers from.  All that pointer to char
> > stuff for strings is what get's me everytime.  Plus C isn't really
> > standardized, no matter what folk tell you!
> >
> Better you should contribute to an ongoing effort than start something
like
> this yourself. You're talking about a *LOT* of code and you'd benefit from
> the knowledge others can bring to the table.

I think our project is different, we have different goals.  I thought about
joining AdaOS early on, but I decided against it.  First I'm not that
experienced with low level stuff and most people there have more than i do.
Also I got confused with the Ada compiler and OS.  I thought they wanted to
do the compiler first and then the OS.  This is wrong as i think you pointed
out (could be wrong it was a while ago).

I've been toying with the idea of dynamic update, which is a bit like the
language TOM's OO facilities but more controlled and more secure.  I've also
been interested in application privilidges/rights.  This is where you say
this program can do, Reading/Writing of Files, TCP/IP and such like.
Anything it tries to do which it isn't registered to do, it can't and get's
the a kick in the ass.  This is to prevent some types of virus and to create
a more secure environment.  I don't know if this will work but I'm going to
try it out at least on paper and see.

One other reason i want to do it as a separate project is that I'm about to
leave uni for 6 months and can devote quality time to it.  Not just an hour
here or there.  Also the team is small, just me and Hermann, which is good.
I think we're going to seek additional help later, but i'd be concerned if
more than say 5 or 6 people got on board in the early stages.

I've also got to convince Hermann about the benefits of Ada, against C.
He's learning C as he goes, but his background is in Pascal.  I think i
persuade him that Ada is a better choice.  This is another reason why i'm
doing the Ada pages to help him into Ada.


> But they seem to be shooting for something more along the
> lines of a WinNT replacement & that's not my interest.

I don't think NT is a good system, it's certainly better than 9X but still.
I also don't rate Unix/Linux much either, but this is cos' it's old
(architecture-wise).  NT is a hybrid microkernel and has some nice features
but it's still has many faults and shouldn't be modelled by anyone.

Saying that Hermann wants to support Unix System V, contrary to what he said
before (no unix clone).  I want to do a new API and maybe Unix as a layer on
top, don't want it in API.  Since our kernel is going to be re-configurable
we'll probably be able to do all manner of API's on top and all manner of
implementations under the hood.  I don't want a huge windows-like API, keep
it small and tidy but fuctional and flexible.  It's a going to be a
microkernel and I've seen a OS's few which use micro-kernels as a base.

You said you wanted a "a solid realtime, embedded subset kernel", why don't
you consult with Hermann and me, and we'll see what comes from it.  This is
just the beginning and we haven't finalised design and any such like.  You
could make some suggestions, and if you're interested in contributing code
then I can talk to Hermann and see what he thinks.  We're doing this in our
spare time, and we understand things like work and life have to go on and
take priority.  We're not going to pressure you.  You could become a member.
You might just contribute to the project that could make windows look like
the Dinosaur of the OS world.

If you're interested mail me at chris.danx@ntlworld or cc_bnf@hotmail.com.
you'll find our site at http://ares.os-4u.com.


Regards,
Chris Campbell

p.s. you can try http://willow.os-4u.com tommorrow night(friday) it'll
probably be a lot further down the road to actually featuring anything
useful then.

Re: Ada Stuff and some confusion

[Mark Lundquist]

chris.danx <chris.danx@ntlworld.com> wrote in message
news:Pb6z6.5897$%W5.648159@news6-win.server.ntlworld.com...
> Hi,
>
> > I was playing off of "Unix". (Also off of an Americanism about retiring
to
> > write "The Great American Novel" - like Mobey Dick.) Not entirely
without
> > some seriousness in there. If you're looking for a name, I'd shoot for
> > something a little sexier and different.
>
> Funnyly we are looking for a name.  Hermann, my OS development partner,

I know, you guys could go for like a personality-cult type thing and call
it:

    "Hermix"!

wait... been done already.
:-) :-)

>
> > But they seem to be shooting for something more along the
> > lines of a WinNT replacement & that's not my interest.
>
> I don't think NT is a good system

You're right -- it sucks

> I also don't rate Unix/Linux much either

Sadly, you're right about that too :-/

> NT is a hybrid microkernel and has some nice features
> but it's still has many faults and shouldn't be modelled by anyone.

strongly agree...

>[...]
> You might just contribute to the project that could make windows look like
> the Dinosaur of the OS world.

If you ask me, Windohs *already* looks like the Dinosaur of the OS World...

Thank you for reading my completely worthless post :-)
Cheers,

Mark Lundquist

Re: Ada Stuff and some confusion

[Mark Lundquist]

Marin David Condic <marin.condic.auntie.spam@pacemicro.com> wrote in message
news:9aip78$i6j$1@nh.pace.co.uk...

> >
> > Kind of like, "I had a lousy guitar teacher: I was self-taught!" :-) :-)
> > -- mark
> >
>
> So *THAT's* why I play such a lousy guitar!

You had me for a teacher? :-)

> And all these years I thought it
> was because I was a poor student! :-)

About the original saying ("The lawyer who represents himself...")... Does
that apply to "language lawyers" or what?

:-)
Cheers,
-- mark

Re: Ada Stuff and some confusion

[Mark Lundquist]

Marin David Condic <marin.condic.auntie.spam@pacemicro.com> wrote in message
news:9ai8dp$cm2$1@nh.pace.co.uk...

>
> In other words, a Definition lays out what a thing looks like - a
> Declaration is what actually makes the thing come into existance. (Sort of
> like the difference between saying "Light: a particle/wave that moves at
> 186000mps..." and "Let There Be Light!")

That's good!

:-)
--mark

Source licensing (was Re: Ada Stuff and some confusion

[Mark Lundquist]

chris.danx <chris.danx@ntlworld.com> wrote in message
news:nh0z6.4622$%W5.458504@news6-win.server.ntlworld.com...
>
> I also want to know about my Ada sources and licensing.  I use GNAT at the
> minute (I don't expect this to change until I win the lottery, and even
then
> I doubt I'll change.  It's the best compiler I've used, ever!).  My
question
> is to do with GPL.  I don't really understand it.  I think it means that
any
> software I write with it must also be GPL'ed (or LGPL'ed).

It doesn't mean that.  We're talking about original *source*code* that you
yourself will author, right?  Well, the only possible way any software
license could have any bearing on that would be if one of the tools you used
to *write* the source code (like an editor, or the operating system) was
licensed to you under conditions imposed on the work product you generate
using the tool, in which case (a) I have no idea whether such a condition
would be legally enforceable (but I rather doubt it); (b) nobody would
release a tool under such a license (because nobody else in turn would use
it, since the point of editors for example is to produce works that you
own), and most importantly, (c) that license would not be the GPL, since the
GPL doesn't say that!  and (d) note that that is totally different than
licensing runtime libraries etc. linked into your work product, there the
issue is that a *copy* (as in, "copyright"!) of the bits is made.

So no, the GNAT license, or any other compiler license, doesn't prevent you
from doing whatever you want to do with source code that you own!

>  Now I have two
> questions about this.  Can I just put a comment in the source, at the top
in
> flashing lights, "this source is licensed under GPL, see license.txt for
> further details" or do I have to include the license in the source.
>

Sure, you don't have to include the full text in the comment.  See
http://www.fsf.org/copyleft/gpl-howto.html.

> My second question is can I ditch the license and go with my own.

Absolutely, you can license it any way you want, or not at all (not grant
anyone the right to make a copy).  Or, you can place it in the public
domain -- then it "belongs to everyone", and anyone can make copies.

If we are talking about the "how to program in Ada" examples, then I would
think a GPL-style source code license would be kind of pointless.  I'd
either place them in the public domain or retain all rights, or just not
sweat it at all.  If we're talking about actual open-source software, then
something like a GPL makes sense.

www.fsf.org has a whole list of various open source licenses that you can
look at (don't be thrown off by the lame "copyleft" terminology).

>  I don't
> really have a problem with making it GPL'ed, but i do find the license too
> wordy in a technical sense.

Well... if you're going to have an open source license, you might start with
something like the GPL and fine-tune the terms to your liking (that assumes
that you care about the terms and studied the GPL enough to understand them
in the first place!)  But I would think that trying to come up with a
simpler "GPL lite" is probably not time well-spent.  After all, the
technical wordiness doesn't make it so onerous to distribute under the GPL
in the first place (see above).  The GPL exists for one purpose, which is to
grant the licensee the right to make and redistribute copies under certain
terms.  If it could be less technical and wordy, while still serving the
purpose for which it was designed, then it would be!

But take a look at the examples on the FSF site...

>
> What about this?
>
>
> <[snip]>
>
> This is just off the top of my head.  Sounds GPLish but clearer i think.

To me, it's a lot less clear than the GPL.  (It's preciesly the technical
wordiness that makes the GPL clearer!)

Best Regards!
-- Mark Lundquist

P.S., thanks for putting up an Ada examples page.  You're doing us all a
favor, and every little bit helps!  Pass the URL along when it's ready! :-)

Re: Ada Stuff and some confusion

[Mark Lundquist]

Marin David Condic <marin.condic.auntie.spam@pacemicro.com> wrote in message
news:9ai8dp$cm2$1@nh.pace.co.uk...
>
> GNAT/GPL: You really need a lawyer for this one

Yeah... (sigh), since Dewar isn't around these days I guess he'd have to
settle for a lawyer :-) :-) :-)

-- mark

Re: Ada Stuff and some confusion

[Martin Dowie]

In the 'general programming' sense the difference between declaration and
definition of a routine can be illustrated by:

procedure Y;  -- declaration of Y

procedure Y is -- definition of Y
begin
  ...
end Y;

i.e. declarations bring the identity and form of an entity into being and
the
definition states what the entity does.

the ARM has things to say about these words in the Ada sense all of its own
and are covered in other replies. :-)

chris.danx <chris.danx@ntlworld.com> wrote in message
news:nh0z6.4622$%W5.458504@news6-win.server.ntlworld.com...
> Now I need you're help again with a general programming question.  I'm
> confused as to the difference between 'declaration' and 'definition'.  I
> remember reading somewhere that many computer programmers don't know or
> confuse them.  I also don't want to put up inaccurate stuff up on the web,
> and proliferate the wrong definitions and add to the situation.

Re: Ada Stuff and some confusion

[chris.danx]

> > I don't think NT is a good system
>
> You're right -- it sucks
...
>
> > I also don't rate Unix/Linux much either
>
> Sadly, you're right about that too :-/

You think NT, Unix/Linux all suck!  What do you use?  Do you program on the
bare boards or what?  <g>


>
> > NT is a hybrid microkernel and has some nice features
> > but it's still has many faults and shouldn't be modelled by anyone.
>
> strongly agree...

Why are AdaOS doing an NT replacement?  Is it going to be a complete clone
only safer cos' it's Ada?  I don't think if you program in Ada and not C, it
immediately makes the OS better or safer.  You can still f**k things up in
Ada and build an unsafe system.  It's just more difficult to do, but you
shouldn't assume that it's a passport to fault free software.

I'm using Ada because it has a better module system, it has a good type
checking system, support for low-level programming and it's standardised.  I
could still make a crap operating system in Ada.

> >[...]
> > You might just contribute to the project that could make windows look
like
> > the Dinosaur of the OS world.
>
> If you ask me, Windohs *already* looks like the Dinosaur of the OS
World...

Raaaaaaaaaaaaaaaaaaaaaaaarrrrrrrgggggggh!


> Thank you for reading my completely worthless post :-)

No post is worthless.  You're sharing your thoughts with the world at large
and getting your point across.


Regards,
Chris Campbell

Re: Source licensing (was Re: Ada Stuff and some confusion

[Larry Kilgallen]

In article <rXaz6.680849$U46.21137064@news1.sttls1.wa.home.com>, "Mark Lundquist" <mark@rational.com> writes:

> It doesn't mean that.  We're talking about original *source*code* that you
> yourself will author, right?  Well, the only possible way any software
> license could have any bearing on that would be if one of the tools you used
> to *write* the source code (like an editor, or the operating system) was
> licensed to you under conditions imposed on the work product you generate
> using the tool, in which case (a) I have no idea whether such a condition
> would be legally enforceable (but I rather doubt it); (b) nobody would
> release a tool under such a license (because nobody else in turn would use
> it, since the point of editors for example is to produce works that you
> own),

I think the VMS Hobbyist license provides a counter-example to those two,
giving free access to the operating system only for non-commercial uses (for
which there is a lot more boilerplate).  Lots of people sign up for those
restrictive terms for home (which is where it must be located) machines.

So popularity is not an issue, and as for enforceability, it would seem
that Compaq's lawyers feel it is enforceable.

Re: Ada Stuff and some confusion

[Marin David Condic]

"Mark Lundquist" <mark@rational.com> wrote in message
news:NS8z6.680454$U46.21107124@news1.sttls1.wa.home.com...
>
> About the original saying ("The lawyer who represents himself...")... Does
> that apply to "language lawyers" or what?
>
I would then have to ask, "Who is the client of a Language Lawyer"? Probably
a compiler. If the language lawyer is arguing in defense of his own
compiler - that may make his motivation suspect, but does that make his
client a fool? The lawyer should, after all, be rational and pragmatic about
the case and a client who has a lawyer with a different agenda is not well
served. But given the "inanimate object" aspects of the situation, I find it
hard to translate.

"The Language Lawyer who represents his own compiler has a Piece Of Crap for
a client."

Does that fly better? :-)

--
Marin David Condic
Senior Software Engineer
Pace Micro Technology Americas    www.pacemicro.com
Enabling the digital revolution
e-Mail:    marin.condic@pacemicro.com
Web:      http://www.mcondic.com/

Re: Ada Stuff and some confusion

[Marin David Condic]

"chris.danx" <chris.danx@ntlworld.com> wrote in message
news:Pb6z6.5897$%W5.648159@news6-win.server.ntlworld.com...
> > But they seem to be shooting for something more along the
> > lines of a WinNT replacement & that's not my interest.
>
> I don't think NT is a good system, it's certainly better than 9X but
still.
> I also don't rate Unix/Linux much either, but this is cos' it's old
> (architecture-wise).  NT is a hybrid microkernel and has some nice
features
> but it's still has many faults and shouldn't be modelled by anyone.
>
Said it was a *replacement* for WinNT - not a WinNT clone. By this, I meant
it is intended to be an OS that would drive around a PC/Workstation -
standalone or possibly in a network. There are other kinds of OS's with
different objectives. From what I can see of AdaOS, there is no intention to
build a kernel that would be acceptable for embedded/realtime work - hence
it is of only peripherial interest to me.


> You said you wanted a "a solid realtime, embedded subset kernel", why
don't
> you consult with Hermann and me, and we'll see what comes from it.  This
is
> just the beginning and we haven't finalised design and any such like.  You
> could make some suggestions, and if you're interested in contributing code
> then I can talk to Hermann and see what he thinks.  We're doing this in
our
> spare time, and we understand things like work and life have to go on and
> take priority.  We're not going to pressure you.  You could become a
member.
> You might just contribute to the project that could make windows look like
> the Dinosaur of the OS world.
>
Well, I'm not into full-blown OS design and any "theory" that I once knew
for OS design has probably been vastly expanded upon since when I was in
school. The basic requirement for an RTOS is predictability. You absolutely
have to have guaranteed latency for things like interrupt handling, context
switching, etc. You also have to guarantee priorities so that the RT
programmer can decide what is most important and know it won't get
sidelined. (Don't stop my #1 priority process just because the OS thinks it
has something more important to do! :-) Beyond that, you've got to provide
means for getting at a variety of hardware either directly or through
drivers (again, with predictable latency & priority!) and you need a few
"creature comforts" like communications mechanisms, etc. The rest is just
providing libraries of subprograms that get specialized jobs done for you.

The problem with an RTOS vs a Workstation OS is that they aim at different
goals and sometimes there is a conflict. If it is possible for a programmer
to write a program that doesn't give up the processor - even to the OS -
this means it is possible to write ill-behaved software. An RTOS has to let
you do that because the application has things to do that can't be
interrupted or delayed. Typically, the RTOS runs only one or a small handful
of very specialized apps and you can get your fingers around the neck of the
guy who does anything stupid or malicious, so this is OK. For a
general-purpose workstation OS, such a capability is rather dangerous and
could lead to all sorts of security holes. (Some workstation RTOSs only
allow certain things to happen if you are "privileged" to do so, but making
sure you don't have security holes can be much more difficult than simply
saying "You can't do that!" and being done with it.)

At the present time, between my "real" job and a small handful of other
sideline projects, I simply don't have time to go tilting at OS windmills.
However, if you guys have questions I might answer, feel free to drop me a
line. As I said, if I could find the RTOS kernel I wanted, there's an app
that is screaming for a superior RTOS & it would be an excellent opportunity
for Ada to break into something new & establish itself. I'll keep your
website bookmarked & check on it periodically. Thanks.

MDC
--
Marin David Condic
Senior Software Engineer
Pace Micro Technology Americas    www.pacemicro.com
Enabling the digital revolution
e-Mail:    marin.condic@pacemicro.com
Web:      http://www.mcondic.com/

Re: Ada Stuff and some confusion

[Ted Dennison]

In article <OThz6.437$cF4.78136@news6-win.server.ntlworld.com>, chris.danx
says...
>Why are AdaOS doing an NT replacement?  Is it going to be a complete clone
>only safer cos' it's Ada?  I don't think if you program in Ada and not C, it

I'm not an AdaOS member, but the impression I get from their website is that it
is supposed to be a completely new (read - incompatable with anything else) OS.
I'm not real sure exactly what they are trying to achieve with it. The only
really intersting concrete detail I could find is that it looks like they want
to build it based on CORBA components, which could make for an interesting
system. If they stick to that as a principle, its OS interface should be farily
unlike any other OS I've ever used. I'd be nifty to see something where users
(not programmers, but users) can plug together small CORBA components to do a
custom job in the same way that Unix users pipe commands through several small
apps.

They also talk some about making it secure and a distributed OS, but there
aren't a lot of details about the distribution, and security exites me about as
much as mowing the lawn...

---
T.E.D.    homepage   - http://www.telepath.com/dennison/Ted/TED.html
          home email - mailto:dennison@telepath.com

Re: Ada Stuff and some confusion

[Ted Dennison]

In article <DZaz6.680858$U46.21137650@news1.sttls1.wa.home.com>, Mark Lundquist
says...
>
>
>Marin David Condic <marin.condic.auntie.spam@pacemicro.com> wrote in message
>news:9ai8dp$cm2$1@nh.pace.co.uk...
>>
>> GNAT/GPL: You really need a lawyer for this one
>
>Yeah... (sigh), since Dewar isn't around these days I guess he'd have to
>settle for a lawyer :-) :-) :-)

The GPL really isn't that tough to read and figure out. Just approach it the way
you would approach reading someone else's code to figure out what's going on. 

In Gnat's case, in general you can use whatever license you want in your own
code, as long as you aren't actually using the source code for the compiler
itself in your product. If you are working for a company, you should by all
means run things by the corporate attorney. However, any licensing problems they
find should probably be treated as "bugs" and reported to ACT. :-)

Note that to achieve this affect, not all of Gnat's sources are under the GPL.
Many of the packages that would commonly be "with"ed by users have a set of
exceptions to the GPL listed in their header files (we commonly term this the
Gnat-Modified GPL, or GMGPL).

---
T.E.D.    homepage   - http://www.telepath.com/dennison/Ted/TED.html
          home email - mailto:dennison@telepath.com

Re: Ada Stuff and some confusion

[chris.danx]

Have you heard of QNX?  Maybe that's what your looking for?

I expect you've heard of it, but you never know.


Thanks,
Chris Campbell

Re: Ada Stuff and some confusion

[Marin David Condic]

Maybe you're just mowing the wrong lawns? :-)

MDC
--
Marin David Condic
Senior Software Engineer
Pace Micro Technology Americas    www.pacemicro.com
Enabling the digital revolution
e-Mail:    marin.condic@pacemicro.com
Web:      http://www.mcondic.com/


"Ted Dennison" <dennison@telepath.com> wrote in message
news:Eykz6.3403$jz.289526@www.newsranger.com...
> They also talk some about making it secure and a distributed OS, but there
> aren't a lot of details about the distribution, and security exites me
about as
> much as mowing the lawn...
>

Re: Ada Stuff and some confusion

[Marin David Condic]

I've heard the buzzword. Not sure it matters to me. My "Windmill Tilting"
hasn't got to do with simply selecting an RTOS. (Got one or more of those
already!) What would be cool is if I had an RTOS that was written in Ada,
suitable for the job at hand - thus allowing Ada to get a toehold on a new
application that might mean lots of new users, etc...

MDC
--
Marin David Condic
Senior Software Engineer
Pace Micro Technology Americas    www.pacemicro.com
Enabling the digital revolution
e-Mail:    marin.condic@pacemicro.com
Web:      http://www.mcondic.com/

"chris.danx" <chris.danx@ntlworld.com> wrote in message
news:LJkz6.1366$IP5.169200@news2-win.server.ntlworld.com...
> Have you heard of QNX?  Maybe that's what your looking for?
>
> I expect you've heard of it, but you never know.
>
>
> Thanks,
> Chris Campbell
>
>
>

Re: Ada Stuff and some confusion

[Ted Dennison]

In article <9akjju$8fg$1@nh.pace.co.uk>, Marin David Condic says...
>
>standalone or possibly in a network. There are other kinds of OS's with
>different objectives. From what I can see of AdaOS, there is no intention to
>build a kernel that would be acceptable for embedded/realtime work - hence
>it is of only peripherial interest to me.

That's about where I am too. I'd rather see a real-time Ada OS, but I don't
really have time to start such a project myself (at least not for the next 6
months or so...). I do try to keep an ear to the ground though. There's
currently an interesting real-time microkernel project ongoing at CMU
(http://www.cs.cmu.edu/afs/cs.cmu.edu/project/art-6/www/rtmach.html). Just like
GNU/HURD is based on MACH, it ought to be possible to build an (Ada coded) RTOS
on top of RT MACH. The sources are available there for downloading, but I don't
know how acceptable the licensing terms would be.

---
T.E.D.    homepage   - http://www.telepath.com/dennison/Ted/TED.html
          home email - mailto:dennison@telepath.com

Re: Ada Stuff and some confusion

[Marin David Condic]

Well, there's still RTEMS which might serve as a kernel, but it isn't
(AFAIK) a full-up RTOS. (More of an RTK to put under your compiler.) I've
not had any experience using it, so I can't really say much.

The trick is that you'd want something a bit more than an RTK - something
that could load programs (in ELF format, maybe?) and execute them as
independent processes. That, and support for lots of the I/O, devices,
etc. - almost a "real" OS, but not quite.

What I'd want is something that provided "basic" OS services, alongside of
which I'd pile the "specialized" libraries of routines to handle the
hardware I've got. That bundle (presuming it had the right capabilities and
was open sourced) could fit into a number of places and would offer the end
user a few things that would make choosing Ada very attractive:

1) Since it isn't a PC environment, you don't have to compete against the
truckloads of development tools & libraries already out there. (There is
competition, but much easier to match.) Ada wouldn't suffer from the
problems it has in other areas where - even if it is a superior language -
the leverage of existing stuff makes Ada a poor choice.

2) Since the OS is in Ada & the libraries are in Ada, it would be natural to
want to build the apps in Ada - although not required. (Extra layers on top
would make it possible to use almost anything - like Java & HTML.)

3) Since its in Ada, there would be (presumably) reliability benefits,
speedier development & less debugging - faster time to market. (Remember,
you're not competing against MSVC++, etc. Everyone else has essentially the
same facilities - very little!) Get out all the standard arguments as to why
Ada is better - throw in some benefits of OOA/OOD/OOP (because your
competition is plain vanilla C!) and I think you end up making a good
business case for it.

4) The adopters of the OS have the edge over the competitors when it comes
to putting apps on top of it. The competition is a bunch of C guys who won't
understand Ada, won't like Ada and won't know how to develop rapidly in Ada.
If you adopt the OS and Ada, you get there with your apps quicker.

5) The end user market is pretty huge (potentially) so it would be
attractive to want to develop for it. Ada could gain quite a few converts in
the process...

Just some random thoughts. I may sideline some of my other projects to look
at this more in depth, but I think it would require a solid starting point
(the core OS - or at least the RTK) or it would just take too long to get
there. Hmmmmm......

MDC
--
Marin David Condic
Senior Software Engineer
Pace Micro Technology Americas    www.pacemicro.com
Enabling the digital revolution
e-Mail:    marin.condic@pacemicro.com
Web:      http://www.mcondic.com/


"Ted Dennison" <dennison@telepath.com> wrote in message
news:uflz6.3475$jz.294146@www.newsranger.com...
> That's about where I am too. I'd rather see a real-time Ada OS, but I
don't
> really have time to start such a project myself (at least not for the next
6
> months or so...). I do try to keep an ear to the ground though. There's
> currently an interesting real-time microkernel project ongoing at CMU
> (http://www.cs.cmu.edu/afs/cs.cmu.edu/project/art-6/www/rtmach.html). Just
like
> GNU/HURD is based on MACH, it ought to be possible to build an (Ada coded)
RTOS
> on top of RT MACH. The sources are available there for downloading, but I
don't
> know how acceptable the licensing terms would be.
>

Re: Ada Stuff and some confusion

[Mark Lundquist]

Ted Dennison <dennison@telepath.com> wrote in message
news:TIkz6.3413$jz.290461@www.newsranger.com...
> >
> >Yeah... (sigh), since Dewar isn't around these days I guess he'd have to
> >settle for a lawyer :-) :-) :-)
>
> The GPL really isn't that tough to read and figure out.

I agree!

My joke was about Dewar, not the GPL!

Cheers,
-- mark    :-)

Re: Ada Stuff and some confusion

[Mark Lundquist]

chris.danx <chris.danx@ntlworld.com> wrote in message
news:OThz6.437$cF4.78136@news6-win.server.ntlworld.com...
>
>
> You think NT, Unix/Linux all suck!  What do you use?

I use NT and Unix.

(but note, I only actually used the word "sucks" for one of those...)

>
> Why are AdaOS doing an NT replacement?

Is that what they're doing?  I don't know much about that effort...

>
> I'm using Ada because it has a better module system, it has a good type
> checking system, support for low-level programming and it's standardised.

Good reasons.

>
> No post is worthless.  You're sharing your thoughts with the world at
large
> and getting your point across.

If only c.l.a. *were* "the world at large"...
:-) :-) :-)

Best,
Mark

Re: Ada Stuff and some confusion

[Marin David Condic]

"Mark Lundquist" <mark@rational.com> wrote in message
news:iwmz6.683154$U46.21227595@news1.sttls1.wa.home.com...
> >
> > Why are AdaOS doing an NT replacement?
>
> Is that what they're doing?  I don't know much about that effort...
>
The confusion is due to one of my posts. AdaOS is *NOT* attempting to be an
NT clone. I used the term "replacement" in the sense that AdaOS would be an
alternative OS for PCs & Workstations (and Servers?). This as opposed to an
RTOS, embedded executive or other form of OS. (Linux could be said to be an
NT "replacement" in the same sense.)

Hope this clears things up before Nick Roberts, et alia, all get upset that
AdaOS is being mischaracterized.

MDC
--
Marin David Condic
Senior Software Engineer
Pace Micro Technology Americas    www.pacemicro.com
Enabling the digital revolution
e-Mail:    marin.condic@pacemicro.com
Web:      http://www.mcondic.com/

Re: Ada Stuff and some confusion

[Florian Weimer]

Ted Dennison<dennison@telepath.com> writes:

> In Gnat's case, in general you can use whatever license you want in your own
> code, as long as you aren't actually using the source code for the compiler
> itself in your product.

For example, this would be the case if you're using ASIS.

Re: Ada Stuff and some confusion

[chris.danx]

MarteOS is supposed to be written in Ada, and it's also supposed to be an
RTOS, but i haven't looked proper yet, so i don't know.

Chris