One of the biggest advantages of free software is that it is usually
written with the needs of its users in mind. Proprietary software,
instead, has more of a tendency to reflect the interests of its owners.
Thus, free applications do not normally implement "features" which allow
their users to do less. One might think that the consensus against "
in free software is nearly universal, but, as the case of the okular
PDF reader in Debian shows, there
are still exceptions.
The PDF file format includes a number of protection flags which specify
whether the reader is allowed to print the file, make changes, or to copy
out excerpts. There is nothing in the format which actively prevents such
activities; these flags are simply instructions which any application
operating on PDF files is expected to observe. If the "no copy" flag is
set, cutting and pasting text from the file should - by the standard - be disabled in any
reader application. Developers of free applications have, as a general
rule, never quite gotten around to implementing this kind of restriction -
even though the low-level poppler PDF-processing library
makes such support possible. Applications which do implement this
"feature" tend to disable it by default.
This is not the case with Okular, though. An attempt to select text from a
suitably-marked PDF file yields a rather confusing dialog which reads "copy
forbidden by DRM" (see the image to the right). Amusingly, the application
will still allow the selected region to be saved as an image file, but
sending the text to the clipboard is not allowed. There is a configuration
option which disables this behavior, but the default setting is to enforce
the copy restriction flag.
John Goerzen encountered this behavior in
Debian's Okular package; suffice to say he was not pleased. He filed a
bug and asked:
So what I want to know is: why are people putting code into Debian
that limits our freedom? Why are people putting such code into KDE?
And can we please patch it to stop that?
One of the important roles played by distributors is to serve as an
intermediary between upstream projects and their users. If a development
project does something which is not in the interests of its users,
distributors have the opportunity, thanks to free licensing, to fix the
problem. A look at a typical distributor's source packages will reveal
that a number of applications have been patched in ways which change their
behavior and generally make them fit in better. This final bit of finish
is part of the value that distributors add.
Given that it's hard to
find users who are asking for copy restriction features, one might think
that this would be an ideal place for the Debian developers in charge of
Okular to provide a more friendly default.
But they do not want to do that. Okular developer Pino Toscano justifies the copy-restriction antifeature by saying that it's
part of the PDF format specification. Since Okular is meant to follow the
standard, it must do so in this case as well. Beyond that, Pino says:
If tomorrow a corporate person complains that Okular does not
respect the PDF format in that sense and that they cannot make use
of it because of that, what should I tell them? They would be
right. Look, having the "power of developers" does not imply
developers should feel like crackers, disabling restrictions just
because they can or in the name of some "freedom".
Additionally, Debian KDE maintainer Sune Vuorela claims that the overhead of maintaining a
patch to Okular would exceed the value gained - though it has been pointed out that the patch is trivial - and
that the real problem is that people are
downloading PDF files with restrictions in the first place. He states that
Okular should not help users to "violate the conditions of use" associated
with the file, but does not say why, if that is a concern, the ability to
ignore copy restrictions is not patched out altogether.
Beyond that, others have raised concerns that failure to enforce copy
restrictions could lead to legal problems in some jurisdictions. It is not
clear which jurisdictions those would be, though. The copying of excerpts
is allowed by fair use rules almost everywhere. Even the DMCA should not
come into play here; the "do not copy" flag is simply a piece of advice
found in the file which does not constitute an "effective technological
measure" in any way. There has been a distinct shortage of legal problems
(or even threats) associated with any of the other PDF readers which fail
to implement this particular behavior. And, if such threats did exist,
the existence of an option to ignore copy restrictions would be problematic
regardless of its default value.
The evince PDF reader ran into this
issue back in 2005. It is now rare to find a distributor shipping a
version of evince which implements copy restrictions. Xpdf implements copy restrictions
unconditionally, but Debian patched that code out in 2002, and that patch
has spread to other distributors as well. In general, as one would
expect, free PDF readers tend not to implement this behavior. Okular is
about the only exception that your editor can find; it's interesting to
note that the version of Okular shipped with Fedora Rawhide also implements
copy restrictions by default. Perhaps this behavior is result of the
relative newness of this application; as it accumulates more users, the
pressure for more user-friendly behavior is likely to grow.
As that pressure mounts, Okular's developers and packagers may find it hard
to justify keeping copy restrictions in place. Linux, at all levels, has
felt free to ignore standards when following them makes no sense. And one
could argue that the copy-restriction flag - which interferes with fair-use
rights while doing nothing to prevent copying of the file or its contents -
makes little sense indeed. This is not a feature which adds value for
Linux users; such features still tend to disappear over time.
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