Add DRAFT note.
[adns] / GPL-vs-LGPL
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c325ceb6 1NB that NO VERSIONS of this file have been released, and I do not
2intend yet to publish this version. If you get an old version of this
3file from my CVS repository definitely do not intend the licence
4exceptions in it to apply - these too were drafts, as you should know
5if you know what retreiving old CVS versions means !
6
7 - Ian Jackson, 2nd March 2000.
8
9DRAFT - DRAFT - DRAFT - DRAFT - DRAFT - DRAFT - DRAFT - DRAFT - DRAFT
10
71ede3cd 11 GPL vs LGPL, in the context of adns
12 -----------------------------------
13
14Several people have asked me to release adns under the GNU Lesser
15General Public Licence (LGPL, formerly the Library GPL) instead of the
16`stronger' GPL. This file is intended to answer most of these
17questions. If you still have questions or comments, please mail me at
18<adns-maint@chiark.greenend.org.uk>.
19
20Typically there are two or three kinds of situation where people make
21this request: the first is where someone is developing a proprietary
22program and wishes to make use of adns but doesn't wish to make their
23program free software. The second case is where a free software
249cf48a 24project is currently using an MIT-like licence or the LGPL and fear
25`GPL infection'. The third case, which often overlaps with the
26second, is where another free software project currently using a
27GPL-incompatible licence, wishes to use adns.
71ede3cd 28
29
301. Proprietary applications of adns
31-----------------------------------
32
33So, let me get this straight. You're writing a proprietary
34program, by which I mean that you will not be distributing source code
35and not allowing users to modify and share your software; most likely
36you are doing this for your own (personal or corporate) financial
37gain.
38
39However, you want to take advantage of adns, software which I have
40spent my time and effort on, and which I release as free software so
41that everyone can improve, share and use it.
42
43Don't you think that is a little hypocritical ? I'm sorry, but I
44don't want you to just take my nice convenient software, without
45giving something back to the free software community or giving the
46same rights to your users as I do to you.
47
48If you really aren't the nasty kind of person I've described here, for
49example if you have a good reason other than your own selfishness for
50wanting to restrict distribution of your program, then perhaps you
51should contact me to discuss it.
52
53
542. GPL-avoiding projects (MIT licence, et al)
55---------------------------------------------
56
57Some free software projects prefer to avoid the GPL and other licences
58which force the software always to be free. Instead they use
59something like the MIT X licence, which allows proprietary versions of
249cf48a 60their software, or the in the case of some free libraries, the LGPL,
61which allows proprietary applications. I have to say that I think
62these people are misguided, but that doesn't mean that they don't have
63a perfect right to.
71ede3cd 64
65Some of these people think that merely writing to an interface
66provided by GPL'd software will cause their program to become GPL'd
67too, even if they don't distribute the GPL'd software. I don't think
68this is the case. I'm perfectly happy for non-GPL'd software to refer
249cf48a 69to adns in its source code. However, I think that exectuables (or
70compiled libraries) which contain or are dynamically linked against
71adns must be GPL'd; likewise executable programs (whether compiled or
72in an interpreted language) which require utilities from adns to
73function properly must be GPL'd.
74
75So, you can distribute your non-GPL'd program source which needs adns
76to compile, but people who wish to distribute binaries must do so
77under the terms of the GNU GPL. This may make sense for some
78GPL-avoiding free software projects; people can still make proprietary
79programs from your code, provided that they make some provision to
80replace adns with something whose copyright allows proprietary
81versions.
82
83However, this doesn't make much sense for the authors of LGPL'd
84libraries. All I can say to them is to ask which is more important:
85that their library be well-constructed and use all the best technology
86available as free software, or whether it is worth degrading quality
87of their library in order to allow proprietary programs to use it !
88
89To help the case of LGPL'd libraries for which adns is not a vital
90component - for example, a library which provides access to other
91libraries so that programs which use it need only use certain parts,
92I have release adns.h (just the public header file) under the LGPL as
93well as the GPL. See the copyright notice in adns.h for details.
94Note that this will not help you if it adns is essential to the
95functioning of your library, because all programs using your library
96must link against both your library and adns and so must be GPL'd.
97
98
99For some information and views from the Free Software Foundation on
100free software licensing, visit:
101
102 Various licenses and comments about them
103 at http://www.fsf.org/philosophy/license-list.html
104
105 Why you shouldn't use the Library GPL for your next library
106 at http://www.fsf.org/philosophy/why-not-lgpl.html
71ede3cd 107
108
1093. GPL-incompatible free software licences
110------------------------------------------
111
112Regrettably, there are a number of free software licences (and
113semi-free licences) in existence which are not compatible with the
114GPL. That is, they impose restrictions which are not present in the
115GPL, and therefore distributing a whole work which contains such a
116program and a GPL'd program is not possible: either the work would
117have to be distributed under the GPL (violating the restrictions made
118by the original author), or under the GPL-incompatible licence
119(violating the GPL).
120
121I may be prepared to make exceptions for such a licence. Please
122contact me at <adns-maint@chiark.greenend.org.uk> with the full text
123of the GPL-incompatible licence. However, I would prefer it if you
124could use a GPL-compatible licence for your project instead.
125
249cf48a 126--- Ian Jackson ...
127
c325ceb6 128DRAFT - DRAFT - DRAFT - DRAFT - DRAFT - DRAFT - DRAFT - DRAFT - DRAFT
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