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* Wrote about GPL Section 3

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@ -832,7 +832,7 @@ receive this no-charge license. Namely, they receive it ``under the terms
of this License'', the GPL. When an entity \emph{chooses} to redistribute
a derivative work of GPL'ed software, the license of that whole derivative
work must be GPL and only GPL\@. In this manner, \S 2(b) dovetails nicely
with \S 6 (as discussed in Section\~ref{GPLs6} of this tutorial).
with \S 6 (as discussed in Section~\ref{GPLs6} of this tutorial).
\medskip
@ -852,7 +852,200 @@ software alongside proprietary software or other unrelated Free Software,
as long as the terms of GPL are adhered to for those packages that are
truly GPL'ed.
\section{GPL, \S 3}
\section{GPL \S 3: Producing Binaries}
% FIXME: need name of a novelist who writes very obscurely and obliquely.
Software is a strange beast when compared to other copyrightable works.
It is currently impossible to make a film or a book that can be truly
obscured. Ultimately, the full text of a novel must presented to the
reader as words in some human-readable language so that they can enjoy the
work. A film, even one directed by David Lynch, must be perceptible by
human eyes and ears to have any value.
Software is not so. While the source code, the human-readable
representation of software is of keen interest to programmers, users and
programmers alike cannot make the proper use of software in that
human-readable form. Binary code --- the ones and zeros that the computer
can understand --- must be producible and attainable for the software to
be fully useful. Without the binaries, be they in object or executable
form, the software serves only the didactic purposes of computer science.
Under copyright law, binary representations of the software are simply
derivative works of the source code. Applying a systematic process (i.e.,
``compilation'') to a work of source code yields binary code. The binary
code is now a new work of expression fixed in the tangible medium of
electronic file storage.
Therefore, for GPL'ed software to be useful, the GPL, since it governs the
rules for creation of derivative works, must grant permission for the
generation of binaries. Furthermore, notwithstanding the relative
popularity of source-based GNU/Linux distributions like ``Gentoo'', users
find it extremely convenient to receive distribution of binary software.
Such distribution is the redistribution of derivative works of the
software's source code. \S 3 addresses the matter of creation and
distribution of binary versions.
Under \S 3, binary versions may be created and distributed under the terms
of \S\S 1--2, so all the material previously discussed applies here.
However, \S 3 must go a bit further. Access to the software's source code
is an incontestable prerequisite for the exercise of the fundamental
freedoms to modify and improve the software. Making even the most trivial
changes to a software program at the binary level is effectively
impossible. \S 3 must ensure that the binaries are never distributed
without the source code, so that these freedoms are ensured to be passed
along the distribution chain.
\S 3 permits distribution of binaries, and then offers three options for
distribution of source code along with binaries. The most common and the
least complicated is the option given under \S 3(a).
\S 3(a) offers the option to directly accompany the source code alongside
the distribution of the binaries. This is by far the most convenient
option for most distributors, because it means that the source-code
provision obligations are fully completed at the time of binary
distribution (more on that later).
Under \S 3(a), the source code code provided must be the ``corresponding
source code''. Here ``corresponding'' primarily means that the source
code provided must be that code used to produce the binaries being
distributed. That source code must also be ``complete''. A later
paragraph of \S 3 explains in detail what is meant by ``complete''. In
essence, it is all the material that a programmer of average skill would
need to actually use the source code to produce the binaries she has
received. Complete source is required so that, if the licensee choses,
she should be able to exercise her freedoms to modify and redistribute
changes. Without the complete source, it would not be possible to make
changes that were actually directly derived from the version received.
Furthermore, \S 3 is defending against a tactic that has in fact been seen
in FSF's GPL enforcement. Under GPL, if you pay a high price for a copy
of GPL'ed binaries (which comes with corresponding source, of course), you
have the freedom to redistribute that work at any fee you choose, or not
at all. Sometimes, companies attempt to build a racket by producing very
specialized binaries (perhaps for an obscure architecture), and then
giving source code that does corresponding, but not giving the
``incantations'' and build plans they used to make that source compile
into the specialized binaries. Therefore, \S 3 that the source code
include ``meta-material'' like scripts, interface definitions, and other material
that is used to ``control compilation and installation'' of the binaries.
In this manner, those further down the distribution chain are assured that
they have the unabated freedom to build their own derivative works from
the sources provided.
FSF (as authors of GPL) realizes that software distribution comes in many
forms. Embedded manufacturers, for example, have the freedom to put
GPL'ed software into their PDAs with very tight memory and space
constraints. In such cases, putting the source right alongside the
binaries on the machine itself might not be an option. While it is
recommended that this be the default way that people comply with GPL, the
GPL does provide options when such distribution is infeasible.
\S 3, therefore, allows source code to be provided on any physical
``medium customarily used for software interchange''. By design, this
phrase covers a broad spectrum. At best, FSF can viably release a new GPL
every ten years or so. Thus, phrases like this must be adaptive to
changes in the technology. When GPL version 2 was first published in June
1991, distribution on magnetic tape was still common, and CD was
relatively new. Today, CD is the default, and for larger systems DVD-ROM
is gaining adoption. This language must adapt with changing technology.
Meanwhile, the binding created by the word ``customarily'' is key. Many
incorrectly believe that distributing binary on CD and source on the
Internet is acceptable. In the corporate world, it is indeed customary to
simply download CDs worth of data over a T1 or email large file
attachments. However, even today in the USA, many computer users with
CD-ROM drives are not connected to the Internet, and most people connected
to the Internet are connected via a 56K dial-up connection. Downloading
CDs full of data is not customary for them in the least. In some cities
in Africa, computers are becoming more common, but Internet connectivity
is still available only at a few centralized locations. Thus, the
``customs'' here have must have a worldwide scope in context, and simply
providing source on the Internet --- while it is a kind, friendly and
useful thing to do --- is not usually sufficient.
Note, however, a major exception to this rule, given by the last paragraph
of \S 3. \emph{If} distribution of the binary files is made only on the
Internet (i.e., ``from a designated place''), \emph{then} simply providing
the source code right alongside the binaries in the same place is
sufficient to comply with \S 3.
\midskip
As is shown above, Under \S 3(a), embedded manufacturers can put the
binaries on the device and ship the source code along on a CD\@. However,
sometimes this turns out to be too costly. Including a CD with every
device could prove too costly, and may practically (although not legally)
prohibit using GPL'ed software. For this situation and others like it, \S
3(b) is available.
\S 3(b) allows a distributor of binaries to instead provide a written
offer for source code alongside those binaries. This is useful in two
specific ways. First, it may turn out that most users do not request the
source, and thus the cost of producing the CDs is saved --- a financial
and environmental windfall. In addition, along with a \S 3(b) compliant
offer for source, a binary distributor might choose to \emph{also} give a
URL for source code. Many who would otherwise need a CD with source might
turn out to have those coveted high bandwidth connections, and are able to
download the source instead --- again yielding environmental and financial
windfalls.
However, note that regardless of how many users prefer to get the source
online, that \S 3(b) does place lasting long-term obligations on the
binary distributor. The binary distributor must be prepared for three
years to honor that offer for source, and ship it out (just as they would
have had to do under \S 3(a)) at a moment's notice when they receive such
a request. There is real organizational cost here: support engineers for
three years must be trained how to route source requests, and source CD
images for every release version for the last three years must be kept on
hand to burn such CDs quickly. The requests might not even come from
actual customers; the offer for source must be valid for ``any third
party''.
That phrase is another place where some get confused --- thinking again
that full public distribution of source is required. The offer for source
must be valid for ``any third party'' because of the freedoms of
redistribution granted by \S\S 1--2. A company may ship a binary image
and an offer for source to only one customer. However, under GPL, that
customer has the right to redistribute that software to the world if she
likes. When she does, that customer has an obligation to make sure that
those who receive the software from her can exercise their freedoms under
GPL --- including the freedom to modify, rebuild, and redistribute the
source code.
This is where \S 3(c) comes into play. Ultimately, \S 3(b) is a big
compromise. It separates the binary software from the key tool that
people can use to exercise their freedom. The GPL permits this separation
because it is good for redistributors, and those users who turn out not to
need the source. However, to ensure equal rights for all software users,
anyone along the distribution chain must have the right to get the source
and exercise those freedoms that require it.
Meanwhile, \S 3(b)'s compromise primarily benefits companies who
distribute binary software commercially. Without \S 3(c), that benefit
would be at the detriment of the companies' customers; the burden of
source code provision would be unfairly shifted to the companies'
customers. A customer, who had received binaries with a \S 3(b)-compliant
offer, would be required under GPL (sans \S 3(c)) to acquire the source,
merely to give a copy of the software to a friend who needed it. \S 3(c)
reshifts this burden to entity who benefits from \S 3(b).
\S 3(c) allows those who undertake \emph{non-commercial} distribution to
simply pass along a \S 3(b)-compliant source code offer. The customer who
wished to give a copy to her friend can now do so without provisioning the
source, as long as she gives that offer to her friend. By contrast, if
she wanted to go into business for herself selling CDs of that software,
she would have to acquire the source and either comply via \S 3(a), or
write her own \S 3(b)-compliant source offer.
This process is precisely the reason why a \S 3(b) source offer must be
valid for all third parties. At the time the offer is made, there is no
way of knowing who might end up non-commercially receiving a copy of the
software. Companies who choose to comply via \S 3(b) must thus be
prepared to honor all incoming source code requests. For this and the
many other additional necessary complications under \S\S 3(b--c), it is
only rarely a better option than complying via \S 3(a).
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\chapter{Defending Freedom On Many Fronts}
@ -872,16 +1065,16 @@ truly GPL'ed.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\chapter{Odds, Ends, and Absolutely No Warranty}
\section{GPL, \S 8}
\section{GPL \S 8}
\label{GPLs8}
\section{GPL, \S 9}
\section{GPL \S 9}
\label{GPLs9}
\section{GPL, \S 10}
\section{GPL \S 10}
\label{GPLs10}
\section{GPL, \S 11}
\section{GPL \S 11}
\label{GPLs11}
There was a case where the disclaimer of a contract was negated because it
@ -1333,4 +1526,4 @@ General Public License instead of this License.
% LocalWords: proprietarize redistributors sublicense yyyy Gnomovision EULAs
% LocalWords: Yoyodyne FrontPage improvers Berne copyrightable Stallman's GPLs
% LocalWords: Lessig Lessig's UCITA pre
% LocalWords: Lessig Lessig's UCITA pre PDAs CDs reshifts