begin Donncha O Caoimh quotation:
> Applications here could be device drivers. The GPL has a special
> clause for operating systems IIRC that lets you link binary drivers
> to a GPLed operating system kernel such as Linux.
Almost. Here's a piece of a mail I recently sent to a company
that was worried about the implications of including a GPL'd program
on the same CD as their own proprietary operating system:
> We talked last week about adding statements to the GPL that
> clarified the intent of the license. Some discussion has
> occurred here and people wonder if this has been done before.
> Do you know of instances where this has been done?
ObIANAL: I am not a lawyer, but a member of the free
software community who has spent time studying
licensing issues and discussing scenarios. What
follows is not legal counsel.
Specifically, this has been done with the Linux kernel itself. The
GPL talks about the ideas of a "work" or a "program", which are, over
time, increasingly imprecise terms. The Linux kernel has a modular
design, and the most cautious interpretation of the GPL would have
loadable device driver modules labeled as a piece of the overall
"work" known as Linux.
Linus Torvalds, however, clarified in writing that he considered the
boundaries of the GPL to go no further than the loadable module
interface. He granted permission for proprietary modules to be
shipped with and loaded into the Linux kernel. Since then, a great
many binary-only drivers have been shipped by hardware manufacturers
who did not wish to release source code.
Section 6 of the GPL says "You may not impose any further restrictions
on the recipients' exercise of the rights granted herein." The
allowance for non-GPL licensed works to work in concert with a GPL
licensed work has been characterised as both a grant of extra rights
(thus not violating section 6) as well as a mere clarification of the
terms in the GPL.
Here's the beginning of /usr/src/linux/COPYING on my machine:
#######################################################################
NOTE! This copyright does *not* cover user programs that use kernel
services by normal system calls - this is merely considered normal use
of the kernel, and does *not* fall under the heading of "derived work".
Also note that the GPL below is copyrighted by the Free Software
Foundation, but the instance of code that it refers to (the Linux
kernel) is copyrighted by me and others who actually wrote it.
Linus Torvalds
----------------------------------------
GNU GENERAL PUBLIC LICENSE
Version 2, June 1991
[...entire GPL follows...]
#######################################################################
There is another instance worth noting.
You may have been familiar with the "KDE wars". Essentially,
the KDE project used a proprietary library of functions known as Qt.
All KDE applications were licensed under the GPL, but Qt was under a
proprietary license that allowed gratis use in GPL'd software.
TrollTech (the company that produced Qt) eventually re-licensed it
under the QPL (a license of their own devising) in response to the
community uproar.
The QPL (as with prior Qt license terms) specifically
permitted unrestricted use in GPL'd applications. Unfortunately, the
GPL did not do the same thing in reverse.
The Debian project, which I follow quite closely, is the
originator of the Open Source Definition, which began as the Debian
Free Software Guidelines. They refused to package and redistribute
the KDE software, as it could not be linked with Qt despite the utter
dependance on same.
The advice of Richard Stallman, the Debian project volunteers,
and a number of other people was that KDE either needed to add
permission to link against Qt or stop distributing KDE. The further
question arose when people pointed out that many KDE applications were
just old GPL licensed applications that had been "converted" to use Qt
without the original copyright holder's consent. As a result of this
particular problem, TrollTech finally released Qt under the GPL,
ending the discussion suddenly.
However, this prompted RMS to put the following up on gnu.org:
The Qt Public License (QPL).
This is a non-copyleft free software license which is
incompatible with the GNU GPL. It also causes major
practical inconvenience, because modified sources can
only be distributed as patches.
We recommend that you avoid using the QPL for anything
that you write, and use QPL-covered software packages
only when absolutely necessary. However, this no
avoidance longer applies to Qt itself, since Qt is now
also released under the GNU GPL.
Since the QPL is incompatible with the GNU GPL, you
cannot take a GPL-covered program and QPL-covered
program and link them together, no matter how.
However, if you have written a program that uses
QPL-covered library (called FOO), and you want to
release your program under the GNU GPL, you can easily
do that. You can resolve the conflict for your program
by adding a notice like this to it:
As a special exception, you have permission to
link this program with the FOO library and
distribute executables, as long as you follow
the requirements of the GNU GPL in regard to
all of the software in the executable aside
from FOO.
You can do this, legally, if you are the copyright
holder for the program. Add it in the source files,
after the notice that says the program is covered by
the GNU GPL.
For reference, this is up at
http://www.gnu.org/philosophy/license-list.html under the
"GPL-Incompatible Licenses" section.
This tactic, while explained in terms of just the QPL, should
theoretically be applicable to any library that may be legally linked
with a GPL-covered program.
Now, this may not be your best tactic in this instance, since
what we really want to do is resolve the conflict created by the
last paragraph of section 2 ("mere aggregation") and the
second-to-last paragraph of section 3 ("...unless that component
itself accompanies the executable.").
My impression is that it is at your discretion to say that
what you plan is an aggregate distribution of software, and not an
accompaniment of components making up a complete work. However, the
"special exception" technique has been published by the Free Software
Foundation as something that authors of free software may use.
The gripes on the OSI license discussion list are that the GPL
has often been subject to Richard Stallman's fickle interpretation.
The consensus there is that this is because no individual
interpretation accompanies most applications of the license.
--
You are not entitled to your opinions.
01234567 <- The amazing indent-o-meter!
^ Matt McIrvin: the Nikola Tesla of tab damage.
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