210 lines
11 KiB
Markdown
210 lines
11 KiB
Markdown
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# FreeBSD, Clang and GCC: Copyleft vs. Community
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A useful perspective explaining why [FreeBSD is moving away from GCC in
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favor of Clang][0]; indeed, they are moving away from GPL-licensed software
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in general. While this is [not a perspective that I personally agree
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with][1], it is one that I will respect for the project. It is worth
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understanding the opinions of those who disagree with you to better
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understand and formulate your own perspective.
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[0]: http://unix.stackexchange.com/a/49970
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[1]: /2012/11/vlcs-move-to-lgpl
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But I am still a free software activist.
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<!-- more -->
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According to the [FreeBSD FAQ][2]:
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> The goal of the FreeBSD Project is to provide a stable and fast general
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> purpose operating system that may be used for any purpose without strings
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> attached.
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As is mentioned in [the aforementioned article][0], the BSD community does not
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hold the same opinions on what constitutes "without strings
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attached"---the BSD community [considers the restriction on the user's
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right to make proprietary use of the software to be a "string"][2],
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whereas the free software community under [RMS][3] believes that [the
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ability to make a free program proprietary is unjust][4]:
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> Making a program proprietary is an exercise of power. Copyright law today
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> grants software developers that power, so they and only they choose the
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> rules to impose on everyone else—a relatively small number of people make
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> the basic software decisions for all users, typically by denying their
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> freedom. When users lack the freedoms that define free software, they
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> can't tell what the software is doing, can't check for back doors, can't
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> monitor possible viruses and worms, can't find out what personal
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> information is being reported (or stop the reports, even if they do find
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> out). If it breaks, they can't fix it; they have to wait for the developer
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> to exercise its power to do so. If it simply isn't quite what they need,
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> they are stuck with it. They can't help each other improve it.
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The [Modified BSD License][5] is a GPL-compatible Free Software
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license---that is, software licensed under the Modified BSD license meets
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the requirements of the [Free Software Definition][6]. The additional
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"string" that the BSD community is referring to is the concept of
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[copyleft][7]---Richard Stallman's copyright hack and one of his most
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substantial contributions to free software and free society. To put it into
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the [words of the FSF][7]:
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> Copyleft is a general method for making a program (or other work) free,
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> and requiring all modified and extended versions of the program to be free
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> as well.
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Critics often adopt the term ["viral" in place of "copyleft"][8] because
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of the requirement that all derivatives must contain the same copyleft
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terms---the derivative must itself be Free Software, perpetually (until, of
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course, the copyright term expires and it becomes part of the public domain,
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[if such a thing will ever happen at this rate][9]). In the case of the
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Modified BSD license---being a more permissive license that is non-copyleft
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and thus allows proprietary derivatives---derivative works that include both
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BSD- and GPL-licensed code essentially consume the [Modified BSD license's
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terms][10], which are a subset of the [GPL's][11]. Of course, this is not
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pursuant to [FreeBSD's goals][2] and so they consider this to be a bad
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thing: There are "strings attached".
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This is more demonstrative of the ["open source" philosophy than that of
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"Free Software"][12] (yes, notice the bias in my capitalization of these
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terms).
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[Copyleft is important][7] because it ensures that all users will forever
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have the [four fundamental freedoms associated with Free Software][6]. The
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GPL incorporates copyleft; BSD licenses do not. Consider why this is a
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problem: Imagine some software Foo licensed under [the Modified BSD
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license][10]. Foo is free software; it is licensed under a [free software
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license (Modified BSD)][5]. Now consider that someone makes a fork---a
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derivative---of Foo, which we will call "Foobar". Since [the Modified BSD
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license is not copyleft][10], the author of Foobar decides that he or she
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does not wish to release its source code; this is perfectly compliant with
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the Modified BSD license, as it does not require that source code be
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distributed with a binary (it only requires---via its [second
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clause][10]---that the copyright notice, list of conditions and disclaimer be
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provided).
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The author has just taken Foo and made it proprietary.
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The FreeBSD community is okay with this; [the free software community is
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not][4]. There is a distinction between these two parties: When critics of
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copyleft state that they believe the GPL is "less free" than more
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permissive licenses such as the BSD licenses, they are taking into
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consideration the freedoms of developers and distributors; the GPL, on the
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other hand, explicirly *restricts* these parties' rights in order to protect
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the *users* because those parties are precisely those that seek to *restrict
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the users' freedoms*; we cannot provide such freedoms to developers and
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distributors without sacrificing the rights of the vulnerable users who
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generally do not have the skills to protect themselves from being taken
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advantage of.[^13] Free software advocates have exclusive, unwaivering
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loyalty to users.
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As an example of the friction between the two communities, consider a
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concept that has been termed ["tivoization"][14]:
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> Tivoization means certain “appliances” (which have computers inside)
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> contain GPL-covered software that you can't effectively change, because
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> the appliance shuts down if it detects modified software. The usual
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> motive for tivoization is that the software has features the manufacturer
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> knows people will want to change, and aims to stop people from changing
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> them. The manufacturers of these computers take advantage of the freedom
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> that free software provides, but they don't let you do likewise.
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This [anti-feature][15] is a type of [Digital Restrictions Management
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(DRM)][16] that exposes a [loophole in the GPL that was closed in
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Section 3 of the GPLv3][14], which [requires that][11]:
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> When you convey a covered work, you waive any legal power to forbid
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> circumvention of technological measures to the extent such circumvention
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> is effected by exercising rights under this License with respect to the
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> covered work, and you disclaim any intention to limit operation or
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> modification of the work as a means of enforcing, against the work's
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> users, your or third parties' legal rights to forbid circumvention of
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> technological measures.
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Unfortunately, not everyone has agreed with this move. A number of
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[developers of the kernel Linux expressed their opposition of GPLv3][17]. In
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response to the aforementioned GPLv3 provision, they stated:
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> While we find the use of DRM by media companies in their attempts to reach
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> into user owned devices to control content deeply disturbing, our belief
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> in the essential freedoms of section 3 forbids us from ever accepting any
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> licence which contains end use restrictions. The existence of DRM abuse is
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> no excuse for curtailing freedoms.
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Linus Torvalds---the original author of the kernel Linux---also [expressed
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his distaste toward the GPLv3][18]; the kernel is today still licensed under
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the GPLv2.
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[The BSD camp has similar objections][19]:
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> Appliance vendors in particular have the most to lose if the large body of
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> software currently licensed under GPLv2 today migrates to the new license.
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> They will no longer have the freedom to use GPLv3 software and restrict
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> modification of the software installed on their hardware. High support
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> costs ("I modified the web server on my Widget 2000 and it stopped
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> running...") and being unable to guarantee adherence to specifications in
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> order to gain licensing (e.g. FCC spectrum use, Cable TV and media DRM
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> requirements) are only two of a growing list of issues for these
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> users. --Justin Gibbs, VP of The FreeBSD Foundation
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My thoughts while reading the above where echoed by Gibbs further on in his
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statement: "[T]he stark difference between the BSD licensing philosophy and
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that of the Free Software Foundation are only too clear." For the FreeBSD
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community, this is a very serious issue and their argument is certainly a
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legitimate concern on the surface. However, it is an argument that the Free
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Software community would do well to reject: Why would we wish to sacrifice
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users' freedoms for any reason, let alone these fairly absurd ones. In
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particular, a support contract could dictate that only unmodified software
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will be provided assistance and even mandate that the hardware indicate
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changes in software: like breaking the "void" sticker when opening a
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hardware component. Moreover, how frequently would such a situation
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actually happen relative to their entire customer base? My guess is: fairly
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infrequently. The second issue is a more complicated one, as I am not as
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familiar on such topics, but a manufacturer can still assert that the
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software that it provides with its devices is compliant. If the compliance
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process forbids any possibility of brining the software into
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non-compliance---that is, allowing the user to modify the software---then
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the hardware manufacturer can choose to not use free software (and free
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software advocates will subsequently reject it until standards bodies grow
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up).
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As I mentioned at the beginning of this article: this is a view that I will
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respect for the project. I disagree with it, but FreeBSD is still free
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software and we would do well not to discriminate against it simply because
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someone else may decide to bastardize it and betray their users by making it
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proprietary or providing [shackles][16]. However, provided the licensing;
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option for your own software, you should choose the GPL.
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**Colophon:** The title of this article is a play on [RMS' "Copyright vs.
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Communty"][20], which is a title to a speech he frequently provides
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worldwide. His speech covers how copyright works against the interests of
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the community; here, BSD advocates aruge that [copyleft][7] works against
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the interests of *their* community and their users; I figured that I would
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snag this title as a free software advocate before someone else opposing
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copyleft did.
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[2]: http://www.freebsd.org/doc/faq/introduction.html#FreeBSD-goals
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[3]: http://en.wikipedia.org/wiki/Richard_Stallman
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[4]: http://www.gnu.org/philosophy/freedom-or-power.html
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[5]: http://www.gnu.org/licenses/license-list.html#ModifiedBSD
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[6]: http://www.gnu.org/philosophy/free-sw.html
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[7]: http://www.gnu.org/copyleft/
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[8]: http://en.wikipedia.org/wiki/Copyleft#Viral_licensing
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[9]: http://www.gnu.org/philosophy/misinterpreting-copyright.html
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[10]: http://en.wikipedia.org/wiki/BSD_licenses
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[11]: http://www.gnu.org/licenses/gpl.html
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[12]: http://www.gnu.org/philosophy/open-source-misses-the-point.html
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[^13]: Technically, the GPL exercises restrictions only on distributors; a
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developer can integrate GPL'd code into their proprietary software so
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long as they do not distribute it [(as defined in the GPL)][11]. However,
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developers often have to cater to distributors, since software will
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generally be distributed; if it is not, then it is not relevant to this
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discussion.
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[14]: http://www.gnu.org/licenses/rms-why-gplv3.html
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[15]: http://www.fsf.org/blogs/community/antifeatures
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[16]: http://www.defectivebydesign.org/what_is_drm_digital_restrictions_management
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[17]: http://lwn.net/Articles/200422/
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[18]: http://en.wikipedia.org/wiki/Linux_kernel
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[19]: http://www.freebsdfoundation.org/press/2007Aug-newsletter.shtml
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[20]: http://www.gnu.org/philosophy/copyright-versus-community.html
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