[cairo] Re: License for cairo changed to LGPL

[Jost Boekemeier]

On Wed, 2004-08-04 at 20:32, Bill Spitzak wrote:
> 1. As a special exception, the copyright holders of this library give 
> permission for additional uses of the text contained in this release of the 
> library as licenced under the FLTK Library Licence, applying either version 2 
> of the Licence, or (at your option) any later version of the Licence as 
> published by the copyright holders of version 2 of the Licence document.
> 
> 2. The exception is that you may link and distribute under terms of your 
> choice, a "work that uses the Library" as defined in section 6 of the 
> License, provided that the creation of this work does not require the 
> modification of any of the source code of the library.

So that I can _copy_ (or static link) the FLTK code into my FLTKX
library, make modifications by adding features not available in FLTK and
distribute this proprietary work without contributing the code to the
original work.  

Clever.  But if you don't care what people do with your code, wouldn't
be the MIT license more appropriate?


> 3. Modifications to the source code of the library do not fall under this

Contradicts with #1,2 above.  Or you must exactly describe how to
identify your work -- API functions usually start with a fltk_, so that
should help, but what about internal structures?


> exception. However you may distribute the modified library under the normal 
> terms of this license and then distribute a work using this modified library 
> using this exception

This confuses me.  What are "normal terms"?  Is that the GPL with the
LGPL linking exception or only the GPL?


> 4. If you copy code from files distributed under the terms of the GNU General 
> Public Licence or the GNU Library General Public Licence into a copy of this 
> library, as this licence permits, the exception does not apply to the code 
> that you add in this way. To avoid misleading anyone as to the status of such 
> modified files, you must delete this exception notice from such code and/or 
> adjust the licensing conditions notice accordingly.

Which special exception do I have to remove?  The one from the LGPL or
the one of the FLTK license -- or both?  


I suggest to rethink your license terms to be more specific a) use the
word "executable" instead of "work" and b) apply the special exceptions
to the GPL directly.  Or, you could use one of the 3 standard fsf
licenses, for example the "guile license":

 As a special exception, the Free Software Foundation gives permission
 for additional uses of the text contained in its release of GUILE.

 The exception is that, if you link the GUILE library with other files
 to produce an executable, this does not by itself cause the
 resulting executable to be covered by the GNU General Public License.
 Your use of that executable is in no way restricted on account of
 linking the GUILE library code into it.

 This exception does not however invalidate any other reasons why
 the executable file might be covered by the GNU General Public License.

 This exception applies only to the code released by the
 Free Software Foundation under the name GUILE.  If you copy
 code from other Free Software Foundation releases into a copy of
 GUILE, as the General Public License permits, the exception does
 not apply to the code that you add in this way.  To avoid misleading
 anyone as to the status of such modified files, you must delete
 this exception notice from them.

 If you write modifications of your own for GUILE, it is your choice
 whether to permit this exception to apply to your modifications.
 If you do not wish that, delete this exception notice.



Jost