[GLLUG] LGPL and GPL - linking and distribution

Charles Ulrich charles at bityard.net
Sun Mar 9 00:21:03 EST 2008


On Sat, Mar 8, 2008 at 7:00 PM, Mike <msg at msu.edu> wrote:
>  So putting a proprietary binary in the same protected memory space is
>  wrong for GPL, but not for LGPL.  Is same memory space considered
>  linking?  (What about the GNU java.  It loads byte-codes into its own
>  memory space.  Is that considered linking?)

The term "memory space" is a bit vague and could refer either to an
application's private memory as allocated by the OS or by the entire
virtual memory space in the kernel (which includes the physical
memory, swap, and then some). The GPL and LGPL were conceived when
most Unix systems used C for just about everything, but the concept of
"linking" code applies to many other types of languages as well. It's
best to think of it in terms of application code versus library code.
The LGPL allows you to use GPL'd programming libraries in your
proprietary applications, but the rest of the GPL provisions still
apply.

If you're really curious about the GPL/LGPL, it would be a good idea
to simply read it. It's a bit long, but pretty easy to read especially
considering that it was written by a lawyer:

http://www.fsf.org/licensing/licenses/gpl.html

>  That's interesting because I ran Firefox, went to "About..." and it said
>  "copyright... all rights reserved...".  When you go to "about:license"
>  and "about:license#exceptions" you see a different license for the
>  official binaries, and something they call a "EULA" (doesn't GPL/LGPL
>  apply to both source and binary files?).  Firefox is supposedly totally
>  MPL/GPL/LGPL, yet what about all the other ones in "about:license"?

Well, Firefox is a bit of a peculiarity in terms of licensing. It's
triple-licensed, so you can simply choose which license you want to
abide by, no matter if you're a developer looking to make a derivative
or an end-user. Firefox also has some restrictions on what you can do
with the official binaries provided by the Mozilla foundation. There's
nothing in the MPL/GPL/LGPL that says they can't do this. The GPL
applies to the software project as a whole, which is comprised of
source and binary files.

The other licenses listed below are the licenses for other software
projects that are included in Firefox. Although they have their own
licenses, the licenses have been verified to be compatible with the
ones that the main Firefox code is based on.

>  It seems if someone distributes some their own GPL/LGPL code, they can
>  later redistribute the same code under a proprietary license too.  Or,
>  later version is totally under a proprietray license.  With copyright
>  power that's possible?

Yes, you can always relicense code that's copyrighted by you. So if I
release FooMaster 1.0 under the GPL and it becomes wildly successful,
I could then decide to take it commercial and release FooMaster 2.0
under a proprietary license.  There's some controversy over whether
you can relicense a specific codebase (i.e., version or range of
versions) that was legitimately released under the GPL previously. I'm
not going to get into that here other than to say it's a definite grey
area.

The only  sticky part to relicensing is the question of what happens
to community contributions to open source code that gets relicensed?
Unless you only accept patches from people who agree to hand over the
copyright to their changes to you, you can't relicense the code that
they wrote without their consent. This is one reason why the Linux
kernel can never be relicensed away from GPLv2. There have been
thousands upon thousands of contributors and tracking each one of them
down to get their approval would be impossible.

>  > You _can_ say "all right reserved" in reference to programB.exe since
>  > you wrote the code and thus hold the copyright to it.
>   >
>  Seems saying "all rights reserved" is typical.  When publishing as
>  GPL/LGPL is there an additional choice about copyright?  For example
>  (1), this is GPL and I give up all copyrights to it.  For example (2),
>  this is GPL.  For example (3), this is GPL + it's copyrighted.  I guess
>  in the 2nd case the code is automaticlly copyrighted these days in the US.

Well, it's entirely likely that I'm not too clear on the legal meaning
of "all rights reserved". But I think you're a tad confused about how
copyright applies to this. Copyright and licensing are two different
things, although the latter depends on the former. Copyright, stated
simply, means that you have complete de facto control over what you do
with the intellectual property that you create. Thus, it is the
foundation upon which software licenses rest. It is copyright that
enables Microsoft to say, "you can purchase a license to use our
software, but you can't give the software away or resell it."
Likewise, copyright enables the owner of a GPL'd program to say, "you
can use my software for free, distribute it freely, modify it and
distribute your changes, just don't remove my copyright and don't
restrict others from having these same freedoms." You can even say, "I
revoke my copyright to this software and release it to the public
domain."

I highly recommend taking a trip over to the FSF and reading up on
their take of copyright (what they call copyleft):
http://www.fsf.org/licensing/essays/copyleft.html

Charles


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