Gtkmm, LGPL and C++

[Neil <mail neilramsden co uk>]

Hi

Gtkmm is really well put together and an inspiring advert for what a 
community can achieve.

I've used it internally and now want to use it for an external 
educational product that I'd need to be able to sell on a commercial basis.

Is there any practical way I can do that without releasing all my code? 
(I don't believe there is.)

Your use of the LGPL for a C++ library that contains template and inline 
code doesn't seem to allow that in practice. (And libsigc++ probably 
goes further in this respect.)

Although you say "Our intent in licensing it in this way is to provide 
it for use through shared libraries in all projects both open and 
proprietary", my reading of the LGPL is that my users would have to have 
the freedom to replace the gtkmm code by a modified version.

The freedom to replace a shared run-time library wouldn't be enough to 
be able modify application code that contains template instantiations. 
At the least, therefore, the LGPL seems to imply that any source code 
that instantiates templates or inline code from gtkmm, needs to be made 
available for re-compiling and linking.

I wonder firstly whether my analysis is correct; and if so, whether that 
is really what you intended in your choice of licence?

Obviously, there's potentially a wider question here over the 
appropriateness of LGPL for any C++ library.

Interestingly, I notice that GNU libstdc++ uses GPL with a runtime 
exception for this reason.

I'd be grateful if you could cast some light on this - I think gtkmm 
deserves to be used as widely as possible and I'd certainly like to know 
whether I can use it legitimately in this particular case.

Many thanks,
Neil.