Re: Simple GTKMM front-end

[John Emmas <johne53 tiscali co uk>]

On 20 Sep 2011, at 07:11, Andy Tai wrote:

> come on... gtkmm is LGPL...

Interesting....  I just checked this on the gtkmm web site and discovered that it's actually released under 
the "GNU Library General Public License".  After further reading it seems that inclusion of the word 
"Library" indicates that this is an old version of what later morphed into the "Lesser General Public 
License" or "LGPL".  Technically though, it's neither GPL nor LGPL in the modern sense.  Clause 5 of the 
"Library" General Public License states:-

" linking a "work that uses the Library" with the Library creates an executable that is a derivative of the 
Library"

[...]

" if the work is a derivative of the Library, you may distribute the object code for the work under the terms 
of Section 6. Any executables containing that work also fall under Section 6, whether or not they are linked 
directly with the Library itself. "

However, sections 6 and 2 seem to state the you need only distribute the source code for any changes you made 
to the library.  For example if your executable uses classes derived from gtkmm, you must release those 
classes (and any modifications that were needed to gtkmm) as a new library in its own right.  However, those 
parts of the executable which make no use of gtkmm do not need to be released.

So it's probably closer to the LGPL than to the GPL but you might still need to release parts of your source 
code.

John