Re: [sigc] Linking dynamically with SigC++ (now rather: License)

[Aristid Breitkreuz <aribrei arcor de>]

Am Donnerstag, den 06.07.2006, 07:58 +0200 schrieb Murray Cumming:
> > Am Mittwoch, den 05.07.2006, 18:49 +0200 schrieb Ulrich Eckhardt:
> >> That's true. LGPL requires that people are able to relink your
> >> executable with
> >> a modified version of the LGPLed code, so either you ship objectfiles or
> >> use
> >> dynamic linking. Or, of course, provide the source.
> >
> > I was once told that sigc++ had no intent of being such restrictive. I
> > asked for a more liberal license because such requirements are not
> > acceptable for my needs. This is why for myself I switched to
> > MPL/GPL/LGPL triple-license. But I was told that
> >      1. sigc++ showed their intent clearly on the website.
> >      2. changing license would be a long-term thing.
> 
> Yes, and nothing has changed since then:
> http://mail.gnome.org/archives/libsigc-list/2006-February/msg00001.html

That was the mail I referred to. This is some relief but not sufficient.

> 
> > But now I read that those restrictions DO apply.
> 
> You didn't read that from a maintainer. You will always hear different
> opinions from different people on legal questions.

I do not think this is a legal question, rather it is a question of
policy. And as such what matters is the policy of _each_ copyright
holder. Obviously there are differences (Ulrich Eckhardts policy is
stricter!?). Also it is not clear to me how binding a notice on a
website can be.

> 
> As stated in that previous email, at some point we should explicit state
> this in an exception in the headers, but I haven't got around to it, and
> nobody has cared enough to write the exception text for us:

Or felt fluent enough in legalese for this. Or really understood the
complications (I do not _fully_ comprehend them, too).

If I understand it correctly, the exception must be bullet-proof (of
course ;-) ) and in difference to the LGPL allow the following
use-cases:
     1. Using all the template stuff (generally code in headers with
        more than 10 lines per functional unit) in libsigc++ from
        application / library code.
     2. Linking libsigc++ statically, at least on Windows or other
        technically restricted platforms (I dislike Windows-DLLs).

Also do you want LGPL 2.1+ or LGPL 2.1 to be the base of the license
(base+exception being the license).

Another proposal would be tri-licensing MPL/GPL/LGPL as does Mozilla.
This is the combination I use for my own free C++ library code. I
basically hope that it's good enough.

Copyright and author's right (I will never again dare to mix those two)
are complicated matters and of vast importance for software developers.

> 
> Murray Cumming
> murrayc murrayc com
> www.murrayc.com
> www.openismus.com
>