"Casper Hornstrup" ch@csh-consult.dk wrote:
Yes, but then you need to publish the sources for the non-free
application under the LGPL.
When using headers to build your application, you create a derived work
of those headers.
http://www.fsf.org/licensing/licenses/lgpl.html
"A "work based on the Library" means either the Library or any
derivative work under copyright
law: that is to say, a work containing the Library or a portion of it,
either verbatim or with
modifications and/or translated straightforwardly into another
language. (Hereinafter, translation
is included without limitation in the term "modification".)"
"4. You may copy and distribute the Library (or a portion or derivative
of it, under Section 2) in
object code or executable form under the terms of Sections 1 and 2
above provided that you accompany
it with the complete corresponding machine-readable source code, which
must be distributed under
the terms of Sections 1 and 2 above on a medium customarily used for
software interchange."
This is rubish. LGPL is understood by most in such a way, that you can use a library in a closed source application as long as you do not make that library a static dependency in your app, meaning that the user could replace that LGPLed library with a newer, compatible version of his and your app still works. Shared libs (or DLLs) clearly are not a static dependency. You are obliged to provide to users of your closed source app and other interested parties the (possibly modified) sources of the LGPL library only, either directly on the media where you distribute your app with or under reasonable terms on request. A download link to Wine seems a very reasonable term to me as long as you didn't make modifications to it, or took care to at least provide a patch with those modifications to the project in question.
With public headers for a library, it could be argued that they do not really provide any code (in most cases) and therefore are even less protectable in the interest of portability and interoperation compatibility.
If it wouldn't be that way nobody could possibly write a closed source application to run under Linux as the kernel and it's headers are under the even more "restrictive" GPL license and every app has to link to the OS kernel (and use the appropriate headers) in some ways to be operable.
Rolf Kalbermatter