Thanks, Olaf. Lots of good information in your post. Looks like I have more research to do.
On Thu, May 12, 2011 at 4:32 PM, Olaf Meeuwissen <olaf.meeuwissen at avasys.jp> wrote: > "scanf @dslextreme.com" <scanf at dslextreme.com> writes: > >> Hi sane-devel, >> >> I'm sure most of you are developers, not lawyers but I'm hoping >> someone can point me in the right direction. I'm trying to figure out >> the best way to release a SANE backend that complies with the GPL >> while protecting the proprietary code it relies on. >> >> [snip] >> >> Instead, I have proposed we develop a SANE backend that uses our >> driver library to control the scanner. It would not contain any >> proprietary code so we could release the backend portion as source >> code. Reliance on binary code excludes it from the SANE distribution >> but that's not a problem. The main issue is the software license. I >> have read the license, copyright notice and Information for >> Manufacturers page but our situation is still unclear. > > Have you gone through the GPL FAQ[1]? ?Especially the bit about the > legal issues that come up if you use GPL-incompatible libraries with GPL > software[2] and writing free software that uses non-free libraries[3]? > > ?[1] http://www.gnu.org/licenses/gpl-faq.html > ?[2] http://www.gnu.org/licenses/gpl-faq.html#GPLIncompatibleLibs > ?[3] http://www.gnu.org/licenses/gpl-faq.html#FSWithNFLibs > >> Here's the big question: If we release our backend as source, does >> that expose our driver library to the GPL so its sources would also >> have to be released? In case it matters, the proposed backend would >> use runtime dynamic linking for the library. > > The way I understand it, you own the copyright of this SANE backend you > proposed so you get to pick the license. ?If you really want to go with > the GPL (which I think is great!), you can add an exception that allows > linking with your proprietary code. ?You could also look at other, more > lax licenses. ?The list of GPL-compatible licenses[4] is a good start. > > ?[4] http://www.gnu.org/licenses/license-list.html#GPLCompatibleLicenses > >> I looked for existing external backends with binary code to see how >> other companies handled the licensing issue. The links I checked on >> the External Backends list were broken or outdated. Can you refer me >> to an existing backend similar to what I've proposed? > > The epkowa backend did the same and still does something similar. ?In > the past it linked dynamically against proprietary interpreters for a > scanner model of two. ?The number of interpreters grew (we've got ~15 > now :-(), so we switched to on-demand dynamic loading instead. ?This > doesn't really make a difference for the licensing issues but it made > the backend free-as-in-freedom for those users that have scanner models > that do not need an interpreter. > > Hope this helps, > -- > Olaf Meeuwissen, LPIC-2 ? ? ? ? ? FLOSS Engineer -- AVASYS CORPORATION > FSF Associate Member #1962 ? ? ? ? ? ? ? Help support software freedom > ? ? ? ? ? ? ? ? http://www.fsf.org/jf?referrer=1962 >
