When "Free" Isn't Good Enough [LWN.net]

[This article was contributed by Joe 'Zonker' Brockmeier]

The GNU Free Documentation License (GFDL) may not be suitable if you're hoping to have your documentation included in Debian "main." The nature of the problem is described in this proposed statement written by Anthony Towns. If adopted as an "official" statement from the Debian project, GFDL-licensed documents will find themselves excluded from the free portion of the Debian distribution.

The conflict between the GFDL and the Debian Free Software Guidelines (DFSG) comes in when the author includes "Invariant" sections or an Acknowledgements or Dedications section. These are described in section 4 of the GFDL. Essentially, the GFDL requires that these sections not be modified or removed, which goes against the (DFSG) requirement that a license "must allow modifications and derived works."

One may avoid the conflict by simply not including the sections that are troublesome, or by using another license. However, that may not satisfy some authors and definitely doesn't solve the problem for documents already accepted.

For many documents, this may not be a problem. If an author insists on using the GFDL and one of the troublesome sections, users can simply grab the documentation elsewhere or even as a Debian package just by getting the package from the "non-free" collection of Debian packages. However, when another program includes the documentation, it may make things a bit trickier. According to Richard Braakman the GFDL puts a "wall between documentation and code."

The GFDL is incompatible with the GPL, and many of its requirements don't translate well to functional software. This makes it difficult to embed such documents into a program, for example in order to present on-line help. In the other direction, many documents contain example code, sometimes sizeable chunks of it, which will be unusable by default unless specifically licensed otherwise.

Braakman also raises a few other issues that he considers problematic with the GFDL. One that is interesting to note is the idea that "languages other than English are poorly supported."

The GNU FDL defines special roles for several kinds of sections (such as "History" and "Dedications"), but refers to these sections by their names in English. A document under the GNU FDL will have to include a section with the title "History", regardless of the language it's written in.

One could ask whether the Debian project should make an exception for documentation. The rules that apply to code may not work so well for documentation, particularly when good documentation is even harder to come by than good code. The Debian developers are not known for compromising on their principles, however. It will be interesting to see what the final outcome of this discussion will be, but it looks entirely likely that the Debian project may decide that one of the GNU Free licenses is, in fact, not free enough.

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When "Free" Isn't Good Enough

Posted May 1, 2003 4:45 UTC (Thu) by piman (subscriber, #8957) [Link]

It's irrelevant to talk about whether or not we should apply different standards to documentation than to code, until we can separate what is code and what is documentation.

If I have a manual in the binary (in strings, for instance), is that code or documentation? Are LaTeX documents, which are in a text-formatting language that also happens to be Turing-complete, code or documentation? (What about (tt LISPS) which can map directly to HTML documents?).

If you go over the debian-legal mailing list, you'll find this issue brought up a number of times, with no satisfactory result. There is no reasonable way to separate documentation from code; there's definitely no reasonable way to license it freely, differently from code.

Appropriate purposes of invariant sections

Posted May 1, 2003 19:58 UTC (Thu) by copsewood (subscriber, #199) [Link]

The GFDL allowance of invariant sections recognises the secondary and primary purposes of free documentation: secondarily to assert origins and opinions, but primarily to enable documentation of a changing code-base to be kept up to date.

It is widely considered abusive to misrepresent the origins of a work (plaigiarism) and offensive to misrepresent the opinions contained within a work attributed to a particular author.

The allowance of invariant sections simply reflects the publishing and academic reality required to prevent such abuse in respect of the secondary purposes of a free software document.

The intention of allowing variant and invariant sections is therefore to distinguish the parts of a work which must not be so abused, from the parts which need to be updated to reflect the technical nature of the software more accurately.

If there is a freedom issue here, in connection with a free operating system distribution which respects the principle of freedom, this might better accept or reject such documentation on quality grounds. Inappropriate choice of variant and invariant sections within a document by its originators should be addressed with these authors on grounds of quality control, as it is not the _primary_ purpose of free software documentation to carry the opinions of its originators or charitable appeals, but preventing such possibilities will remove one of the incentives which result in free software being written.

Appropriate purposes of invariant sections

Posted May 1, 2003 20:58 UTC (Thu) by piman (subscriber, #8957) [Link]

This could be the case if invariant sections had to be, e.g. removed if the document is changed. This is not the case. They cannot be removed, and they cannot be changed, even if the rest of the document is. One example Debian uses is that some GNU manuals contains an invariant section "Why you should use the GFDL". Debian could add an invariant section right after it "Why you should not use the GFDL". No one could remove either one (although people getting it from GNU, rather than Debian, would only see the first one - unless Debian's maintains started submitting patches to GNU, like they often do, but with the invariant section attached).

One of my key complaints is that invariant sections are unremovable (see all the comments on the debian-legal mailing list over the past year or so). This creates tons of practical problems (including all invarant sections on a reference card derived from the documentation? Impossible), as well as ideological problems (such as the above case). If they were removable, we could just remove the invariant sections and the resulting document would be unquestionably free - although possibly not entirely as useful.

This is ignoring the odd problems about "opaque" and "transparent" copies, or the problems of the GFDL being GPL-incompatible, or the fact the GFDL in fact exhibits the exact same problem the FSF says the BSD license has.

The "invariant sections protect the author's integrity" argument has been discussed extensively on debian-legal, and IMO, thoroughly debunked.

What about invariant sections of the license?

Posted May 2, 2003 12:57 UTC (Fri) by hazelsct (subscriber, #3659) [Link]

One of the comments on debian-legal involved the problematic prohibition on removing "manifestoes" from invariant sections from various pieces of potentially GFDL software. But doesn't that also pose a problem for (L)GPL code? After all, the (L)GPL "preamble" is just such a manifesto with no legal function whatsoever, but must be distributed with the software and all of its derivatives.

Likewise, a GFDL workaround which satisfies the letter (but not the spirit?) of DFSG is to have the author invent a new license which is the GPL plus her important texts. Since this license must be distributed with the code/doc, these texts become invariant sections.

Would Debian distribute software thus licensed? How is this different from a GFDL code/doc?