Dynamic linking, was: Re: Dispelling BSD License Misconceptions

[Ben Tilly]

On 1/18/07, Matthew Flaschen <matthew.flaschen at gatech.edu> wrote:
> Ben Tilly wrote:
[..]
> > I didn't say that.  Or rather, I said that about another piece of
> > code.  Here are the pieces of code of interest:
> >
> > 1. Perl minus Term::ReadLine
> > 2. Term::ReadLine
> > 3. Term::ReadLine::Gnu
> > 4. Code written in Perl
> >
> > I think the first is obviously not derivative
>
> I agree here.
>
> , the second I strongly
> > doubt is derivative
>
> Still with you.
>
> , the third I'm inclined to think would be (but
> > don't feel qualified to judge)
>
> Same.
>
> , and the last is generally not but in
> > some cases could be.
>
> I'm not sure about this one.  I'm also still confused what you mean by
> "the author of Term::ReadLine::Gnu may be overstepping".  Who is
> overstepping, and why?

Well I think the third is probably derivative.  But the author of that
code thinks he can dual license it Artistic and GPL.  Which means that
he either hasn't paid enough attention to readline's copyright
license, or doesn't think that his work is derivative.

Hence he may be overstepping - asserting that he has a right to apply
a license that he may not.

About the one you're not sure of, most Perl code does not even *load*
Term::ReadLine.  That's not going to be derivative.  Of code that does
load it, most uses only the Term::ReadLine API.  I think we're agreed
that that is unlikely to be derivative.  But the tiny portion of
fraction that specifically loads Term::ReadLine::Gnu and then heavily
uses parts of the API that are specific to readline - there probably
is some code that might be argued to be derivative of readline.

So general Perl code is generally not derivative of readline, but
there are probably some examples out there that could be.

Cheers,
Ben