From: Ben Giddings <bg-rubytalk@...>
Date: 2004-08-07T01:19:08+09:00
Subject: Re: Amazing GUI toolkit with visual designer & Ruby Integration

H. Simpson, please calm down.  Take a few deep breaths.  Think before 
posting.  Don't use personal attacks.  Your email was inflammatory and 
rude.  It was also proposing a pretty improbable scenario.  If someone 
spent their life savings building an application, I would hope they 
wouldn't use some random comments from some internet user as a 
substitute for legal advice.

Having said that, Lothar is incorrect.

The GPL and LGPL require you to do much more than place a diff file on a 
website.  I read through the LGPL, and I won't pretend to understand 
exactly what it requires, but here are some relevant sections:

"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.

"If distribution of object code is made by offering access to copy from 
a designated place, then offering equivalent access to copy the source 
code from the same place satisfies the requirement to distribute the 
source code, even though third parties are not compelled to copy the 
source along with the object code."

In other words, you have to supply more than just diff output, you have 
to supply the entire source code.

It also mentions:

"For an executable, the required form of the "work that uses the 
Library" must include any data and utility programs needed for 
reproducing the executable from it. However, as a special exception, the 
materials to be distributed need not include anything that is normally 
distributed (in either source or binary form) with the major components 
(compiler, kernel, and so on) of the operating system on which the 
executable runs, unless that component itself accompanies the executable."

I'm pretty sure that the intention of the GPL and LGPL is that the part 
of the code for which that license applies has to be distributed in the 
same form you receive it.  If you receive it as a "configure" script, a 
bunch of Makefiles, and some .c and .h files, that's how you have to 
provide it.

But from reading the rest of the LGPL, it looks as though if you 
dynamically link to an LGPLed library, you are required to provide 
notice that you do so, and provide a source code distribution for the 
library.  The application itself can be distributed under any terms that 
don't violate the LGPL for the library part.  Statically linking is a 
different matter entirely.

But, like I said, I don't fully understand the LGPL or the GPL and would 
suggest that anybody who is thinking of using them and wants to avoid 
redistribution of their source code under the same license should be 
careful and probably consult a lawyer.

Ben