Re: Lilypond \include statements and the GPL

[Anthonys Lists]

On 02/04/2013 23:28, Joseph Rushton Wakeling wrote:
> On 04/03/2013 12:01 AM, Anthonys Lists wrote:
> > But as I understand it, the lawsuit as actually sued said "apis are copyright"
> > and you would have needed a licence to use the apis - to use Oracle's Java.
> That's exactly in line with what David said.  Google were providing a clean-room
> re-implementation -- the only thing it had in common with Oracle's Java was the 
> API.
>
> Oracle couldn't sue on the basis of code duplication, so they tried to stop
> Google distributing their implementation by claiming copyright violation on the
> basis of duplication of the API.  And (rightly) lost.
>
> That's a different situation from the one we have been discussing here, which is
> code that _uses_ (not implements) functions whose only existing implementation
> is in a GPL-licensed program.
Think of the API as a looking glass. On one side you have the code that 
IMPLEMENTS the api. On the other side we have the code that CALLS the api.

Correct - Oracle wanted to stop Google writing new code to IMPLEMENT the 
api (that's what David said).

BUT - iirc what Oracle actually sued over was "using the looking glass". 
Which would have stopped people writing code that CALLS the api (that's 
what I said).

And that IS exactly the situation we have with lilypond. Using an api - 
in either direction - is not copyrightable. So if your lilypond text 
file calls a GPL lilypond function, it is not subject to the GPL because 
the api cannot be copyrighted. (If you copy the function 
*implementation* into your file, of course you then do get caught by 
copyright.)

Cheers,
Wol