Re: GLADE and GPL (was: what DOES the GPL really say?)

[dewar@merv.cs.nyu.edu (Robert Dewar)]

Dave says

<<I've been following this thread for a little bit, and I'd like to toss
in my opinion (what th' heck, right?).  The significant difference
between the GPL and the ACL is much like the difference between
capitalism and communism*.  The GPL assumes all users are sinners, and
takes the approach of requiring the users to affirm, by usage of
GPL'ed code, that they will not unfairly exploit the free software
they are taking advantage of.  There's all sorts of legal stuff in
>>



This is complete nonsense, and frankly I am a little surprised at the
level of misunderstanding (I would have thought Dave understood the
philosophy behind the GPL better).

The business about the GPL assuming all users are sinners is fanciful
stuff, but bears no relation to reality.

The real point is a purely pragmatic one. Most people think of public
domain software as being software that anyone can do anything with.


Yes, indeed they can, they can make a minor modification, or even just
reformat the code, and then copyright the result and make it proprietary.

Why does this bother us? Because of some philosophical concern about
what is right and wrong in the software world? Because we want to be
sure to get proper credit for our work? Becuase we do not want people
to unfairly profit from what we do?

NONE OF THE ABOVE!

The concern is purely pragmatic. We are writing software that we want
to be available to the general comunity and *stay available to the
general community*. It is the stay available that is the concern.

Suppose the government had not insisted on GNAT being under the GPL, and
instead the NYU team placed it under the less restrictive, supposedly
freer ACL.

Now, when the contract ended, sure enough the version of GNAT available
at that time (1.something???) would be available to everyone.

But Ada Core Technologies could have then taken that version, and 
developed it as a purely proprietary product and charged whatever
they liked for it. 

The big value of a product like GNAT is precisely that it remains open
to general use. Commercialization of this kind would have complete
undermined one of the important purposes of GNAT, which was to provide
a high quality Ada 95 compiler, available to the general academic
community with sources, and which would continue to be available.

Sure, in theory, someone else could take the 1.xx versoin and develop
it independently, but that is an unlikely scenario. We have over and over
again seen freely available academic products turn into proprietary
products that are no longer freely available.

We thought it was important to ensure that this could not happen with GNAT,
and so did the government, which is why it insisted on the use of the GPL.

Going back to the Booch components, Dave is of course free to choose any
approach he likes for his work, but in practice the only difference between
the ACL and the use of a broadened GPL such as is used by GNAT is that
it makes it possible for someone to produce a proprietary version of
these components based on Dave's work.

I personally think that having a freely available version of the Ada 95
form of the components is a tremendous advantage to tthe Ada community.
If some company takes this and commecializes it so that a few years from
now you have a situation where the only really usable version is a 
proprietary version that you have to pay for and cannot get full source
access, then we have lost something valuable.

That's why I think it is unfortunate to use the ACL instead of the modified
GPL for such projects, it seems freer, but can very easily lead to much
less freedom.

Note another scenario which is even worse.

Suppose the GNU components which along with Linus' kernel make up the
GNU-based Linux system had been written under something analogous to
the ACL.

Today we have three companies competing in the support of Linux, but all
the changes an improvements they make are available to one another and
to the entire Linux community.

If the GPL had not been used, we might see three divergent versions of
Linux, all proprietary, with competing features. The tremendous value
of Linux and the original GNU vision would be essentially lost, and we
would have just a few more incomaptible miscellaneous Unix versions around.

THe whole point of the GPL is entirely pragmatic. The idea is to make
as much software as possible as freely available as possible, because this
free availability benefits users.

I gave a talk at the Ada Europe Conference on why free software was of
tremendous importance in building reliable systems. The key point here is
that you cannot afford to build reliable systems on top of black box
layers of operating systems, real time kernels, and Ada runtime systems
for which you have no access to the sources, or only limited access to
the sources. For high reliability code, you need total control.

Note that if it were really true that the only point behind the GPL were
the kind of philosophical issues that Dave refers to, then obviousoly there
would be no such thing as the modified GPL or the LGPL. The idea of allowing
this modification is precisely to make it possible to create proprietary
tools using GNU compilers.

Now, why would the FSF encourage that? Simple, the argument is pragmatic.
if we encourage everyone to use free software compilers and systems, then
more resources will be available to improve and support these compilers
and systems, and these improvements benefit all users.

Yes, obviously from the user community point of view, it would be desirable
if the software being produced were freely available rather than proprietary,
but it is important to understand that the issue here is a pragmatic one,
not purely a philosphical one.

The idea of free software is to promote an environment in which the
computing community can get its job done more effectively. The tremendous
success of Linux shows that this idea can be a powerful one. More and more
people are switching to using Linux, not because they want to join some
polictical movement, but because it is the best technical tool for the job!

Robert dewar
Ada Core Technologies