Re: [fluid-dev] fluidsynth on iphone

[Matt Giuca]

Hi Paul,
I'm just an outside observer and not a lawyer, but I believe that's
insufficient.

> Would it be ok if we proced as follows:
>  - mention that we use Fluidsynth in the 'about' section
>  - add a link to http://fluidsynth.org
>  - include a copy of the LGPL license in the package

>From the text of the FluidSynth license, the LGPL v2.0
(http://www.gnu.org/licenses/old-licenses/lgpl-2.0.html):
Section 6 states that you must:
"Accompany the work ... if the work is an executable linked with the
Library, with the complete machine-readable "work that uses the
Library", as object code and/or source code, so that the user can
modify the Library and then relink to produce a modified executable
containing the modified Library."
(there are a few other options, but they all pretty much lead to the
same thing.)

Where the "work that uses the Library" is your iPhone app. That means
that you must supply either the full source code to your iPhone app,
or supply compiled object files to the app, such that it's possible
for any user to:
1. Modify FluidSynth or download an updated version of FluidSynth, and
2. Link your iPhone app with the modified version of FluidSynth, and
run the new version on an iPhone.

(This would mean users have the freedom to run, study, modify and
redistribute the code to FluidSynth portion of your program, even if
they can't do that to the whole program.)

There is a good explanation of this here:
http://huyzing.com/2009/08/24/compatibility-between-the-iphone-app-store-and-the-lgpl/

Secondly, Section 10 of the LGPL states that:
"Each time you redistribute the Library (or any work based on the
Library), the recipient automatically receives a license from the
original licensor to copy, distribute, link with or modify the Library
subject to these terms and conditions. You may not impose any further
restrictions on the recipients' exercise of the rights granted
herein."

By distributing FluidSynth through the iTunes store, you are requiring
your end users accept the iTunes Store Terms of Service, which does
impose further restrictions on the recipients. For instance, Apple
will force you to license the product (including FluidSynth) to your
users under the terms: "You may download and sync a Product for
personal, noncommercial use on any device You own or control," and
"You shall be able to store App Store Products on five
iTunes-authorized devices at any time." In requiring that your users
comply with Apple's terms, you would be violating the LGPL.

This second point is quite blurry and I'm not sure if it applies in
this situation (as I said, I'm not a lawyer), but that's how I read
it. There is a detailed explanation of the conflict between section 10
of the LGPL (that article mentions section 6 of the GPL, but the
wording is the same) and Apple's terms of service here:
http://www.fsf.org/news/blogs/licensing/more-about-the-app-store-gpl-enforcement

But you will definitely need to comply with Section 6 by including at
least object files, makefiles, etc, for your program. Alternatively,
you could get a separate agreement from the FluidSynth developers
which falls outside of the LGPL.

Matt Giuca