[xsd-users] License and Portability

[Peter Backes]

On Sun, Jun 19, 2011 at 06:21:28PM +0200, Boris Kolpackov wrote:
> Klaim - Joël Lamotte <mjklaim at gmail.com> writes:
> 
> > 1. The xsd license is GPL even for generated code, right?
> > As my project's license is MIT and I wish companies to build over my code,
> > using xsd to generate code forces me and other companies using or selling my
> > tool to provide the source code or to have a commercial license with your
> > company? Am I correct?
> 
> In addition to the GPL we also have the Free/Libre and Open Source 
> Software (FLOSS) exception which, provided you actually build 
> something useful on top of the generated code, allows you to 
> effectively re-license the generated code under other open-source 
> licenses, including MIT. For more information see the FLOSSE text 
> which has a nice "Intent" section including more detail on situations 
> where it can and cannot be used:

The FSF has generally taken the position that you cannot claim 
copyright of the output users generate with the help of your program, 
except if that program copies some significant amount of its source 
code into the output.  That is why gcc compiled programs need not be 
put under the GPL.

Thus, IMO, the only thing that prevents XSD users from choosing any 
license they want is the fact that the header-only XSD runtime library 
is needed to make an executable.

http://www.codesynthesis.com/projects/xsd/FLOSSE seems wrong to me when 
it justifies its claims by also referring to "XSD generated code"

See http://www.gnu.org/licenses/gpl-faq.html

 Is there some way that I can GPL the output people get from use of my 
 program? For example, if my program is used to develop hardware 
 designs, can I require that these designs must be free?

    In general this is legally impossible; copyright law does not give 
    you any say in the use of the output people make from their data 
    using your program. If the user uses your program to enter or 
    convert his own data, the copyright on the output belongs to him, 
    not you. More generally, when a program translates its input into 
    some other form, the copyright status of the output inherits that 
    of the input it was generated from.

    So the only way you have a say in the use of the output is if 
    substantial parts of the output are copied (more or less) from text 
    in your program. For instance, part of the output of Bison (see 
    above) would be covered by the GNU GPL, if we had not made an 
    exception in this specific case.

    You could artificially make a program copy certain text into its 
    output even if there is no technical reason to do so. But if that 
    copied text serves no practical purpose, the user could simply 
    delete that text from the output and use only the rest. Then he 
    would not have to obey the conditions on redistribution of the 
    copied text. 

 In what cases is the output of a GPL program covered by the GPL too?

    Only when the program copies part of itself into the output.

Regards
Peter
-- 
Peter Backes, rtc at cdl.uni-saarland.de            Office 403
Compiler Design Lab, Saarland University         Campus E1 3
Phone: +49-681-302-2454, Fax: -3065              66123 Saarbruecken
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