FreeCAD

1
		  GNU LIBRARY GENERAL PUBLIC LICENSE
2
		       Version 2, June 1991
3

4
 Copyright (C) 1991 Free Software Foundation, Inc.
5
                    51 Franklin Street - Fifth Floor
6
                    Boston, MA 02110-1301, USA.
7
 Everyone is permitted to copy and distribute verbatim copies
8
 of this license document, but changing it is not allowed.
9

10
[This is the first released version of the library GPL.  It is
11
 numbered 2 because it goes with version 2 of the ordinary GPL.]
12

13
			    Preamble
14

15
  The licenses for most software are designed to take away your
16
freedom to share and change it.  By contrast, the GNU General Public
17
Licenses are intended to guarantee your freedom to share and change
18
free software--to make sure the software is free for all its users.
19

20
  This license, the Library General Public License, applies to some
21
specially designated Free Software Foundation software, and to any
22
other libraries whose authors decide to use it.  You can use it for
23
your libraries, too.
24

25
  When we speak of free software, we are referring to freedom, not
26
price.  Our General Public Licenses are designed to make sure that you
27
have the freedom to distribute copies of free software (and charge for
28
this service if you wish), that you receive source code or can get it
29
if you want it, that you can change the software or use pieces of it
30
in new free programs; and that you know you can do these things.
31

32
  To protect your rights, we need to make restrictions that forbid
33
anyone to deny you these rights or to ask you to surrender the rights.
34
These restrictions translate to certain responsibilities for you if
35
you distribute copies of the library, or if you modify it.
36

37
  For example, if you distribute copies of the library, whether gratis
38
or for a fee, you must give the recipients all the rights that we gave
39
you.  You must make sure that they, too, receive or can get the source
40
code.  If you link a program with the library, you must provide
41
complete object files to the recipients so that they can relink them
42
with the library, after making changes to the library and recompiling
43
it.  And you must show them these terms so they know their rights.
44

45
  Our method of protecting your rights has two steps: (1) copyright
46
the library, and (2) offer you this license which gives you legal
47
permission to copy, distribute and/or modify the library.
48

49
  Also, for each distributor's protection, we want to make certain
50
that everyone understands that there is no warranty for this free
51
library.  If the library is modified by someone else and passed on, we
52
want its recipients to know that what they have is not the original
53
version, so that any problems introduced by others will not reflect on
54
the original authors' reputations.
55

56
  Finally, any free program is threatened constantly by software
57
patents.  We wish to avoid the danger that companies distributing free
58
software will individually obtain patent licenses, thus in effect
59
transforming the program into proprietary software.  To prevent this,
60
we have made it clear that any patent must be licensed for everyone's
61
free use or not licensed at all.
62

63
  Most GNU software, including some libraries, is covered by the ordinary
64
GNU General Public License, which was designed for utility programs.  This
65
license, the GNU Library General Public License, applies to certain
66
designated libraries.  This license is quite different from the ordinary
67
one; be sure to read it in full, and don't assume that anything in it is
68
the same as in the ordinary license.
69

70
  The reason we have a separate public license for some libraries is that
71
they blur the distinction we usually make between modifying or adding to a
72
program and simply using it.  Linking a program with a library, without
73
changing the library, is in some sense simply using the library, and is
74
analogous to running a utility program or application program.  However, in
75
a textual and legal sense, the linked executable is a combined work, a
76
derivative of the original library, and the ordinary General Public License
77
treats it as such.
78

79
  Because of this blurred distinction, using the ordinary General
80
Public License for libraries did not effectively promote software
81
sharing, because most developers did not use the libraries.  We
82
concluded that weaker conditions might promote sharing better.
83

84
  However, unrestricted linking of non-free programs would deprive the
85
users of those programs of all benefit from the free status of the
86
libraries themselves.  This Library General Public License is intended to
87
permit developers of non-free programs to use free libraries, while
88
preserving your freedom as a user of such programs to change the free
89
libraries that are incorporated in them.  (We have not seen how to achieve
90
this as regards changes in header files, but we have achieved it as regards
91
changes in the actual functions of the Library.)  The hope is that this
92
will lead to faster development of free libraries.
93

94
  The precise terms and conditions for copying, distribution and
95
modification follow.  Pay close attention to the difference between a
96
"work based on the library" and a "work that uses the library".  The
97
former contains code derived from the library, while the latter only
98
works together with the library.
99

100
  Note that it is possible for a library to be covered by the ordinary
101
General Public License rather than by this special one.
102

103
		  GNU LIBRARY GENERAL PUBLIC LICENSE
104
   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
105

106
  0. This License Agreement applies to any software library which
107
contains a notice placed by the copyright holder or other authorized
108
party saying it may be distributed under the terms of this Library
109
General Public License (also called "this License").  Each licensee is
110
addressed as "you".
111

112
  A "library" means a collection of software functions and/or data
113
prepared so as to be conveniently linked with application programs
114
(which use some of those functions and data) to form executables.
115

116
  The "Library", below, refers to any such software library or work
117
which has been distributed under these terms.  A "work based on the
118
Library" means either the Library or any derivative work under
119
copyright law: that is to say, a work containing the Library or a
120
portion of it, either verbatim or with modifications and/or translated
121
straightforwardly into another language.  (Hereinafter, translation is
122
included without limitation in the term "modification".)
123

124
  "Source code" for a work means the preferred form of the work for
125
making modifications to it.  For a library, complete source code means
126
all the source code for all modules it contains, plus any associated
127
interface definition files, plus the scripts used to control compilation
128
and installation of the library.
129

130
  Activities other than copying, distribution and modification are not
131
covered by this License; they are outside its scope.  The act of
132
running a program using the Library is not restricted, and output from
133
such a program is covered only if its contents constitute a work based
134
on the Library (independent of the use of the Library in a tool for
135
writing it).  Whether that is true depends on what the Library does
136
and what the program that uses the Library does.
137
  
138
  1. You may copy and distribute verbatim copies of the Library's
139
complete source code as you receive it, in any medium, provided that
140
you conspicuously and appropriately publish on each copy an
141
appropriate copyright notice and disclaimer of warranty; keep intact
142
all the notices that refer to this License and to the absence of any
143
warranty; and distribute a copy of this License along with the
144
Library.
145

146
  You may charge a fee for the physical act of transferring a copy,
147
and you may at your option offer warranty protection in exchange for a
148
fee.
149

150
  2. You may modify your copy or copies of the Library or any portion
151
of it, thus forming a work based on the Library, and copy and
152
distribute such modifications or work under the terms of Section 1
153
above, provided that you also meet all of these conditions:
154

155
    a) The modified work must itself be a software library.
156

157
    b) You must cause the files modified to carry prominent notices
158
    stating that you changed the files and the date of any change.
159

160
    c) You must cause the whole of the work to be licensed at no
161
    charge to all third parties under the terms of this License.
162

163
    d) If a facility in the modified Library refers to a function or a
164
    table of data to be supplied by an application program that uses
165
    the facility, other than as an argument passed when the facility
166
    is invoked, then you must make a good faith effort to ensure that,
167
    in the event an application does not supply such function or
168
    table, the facility still operates, and performs whatever part of
169
    its purpose remains meaningful.
170

171
    (For example, a function in a library to compute square roots has
172
    a purpose that is entirely well-defined independent of the
173
    application.  Therefore, Subsection 2d requires that any
174
    application-supplied function or table used by this function must
175
    be optional: if the application does not supply it, the square
176
    root function must still compute square roots.)
177

178
These requirements apply to the modified work as a whole.  If
179
identifiable sections of that work are not derived from the Library,
180
and can be reasonably considered independent and separate works in
181
themselves, then this License, and its terms, do not apply to those
182
sections when you distribute them as separate works.  But when you
183
distribute the same sections as part of a whole which is a work based
184
on the Library, the distribution of the whole must be on the terms of
185
this License, whose permissions for other licensees extend to the
186
entire whole, and thus to each and every part regardless of who wrote
187
it.
188

189
Thus, it is not the intent of this section to claim rights or contest
190
your rights to work written entirely by you; rather, the intent is to
191
exercise the right to control the distribution of derivative or
192
collective works based on the Library.
193

194
In addition, mere aggregation of another work not based on the Library
195
with the Library (or with a work based on the Library) on a volume of
196
a storage or distribution medium does not bring the other work under
197
the scope of this License.
198

199
  3. You may opt to apply the terms of the ordinary GNU General Public
200
License instead of this License to a given copy of the Library.  To do
201
this, you must alter all the notices that refer to this License, so
202
that they refer to the ordinary GNU General Public License, version 2,
203
instead of to this License.  (If a newer version than version 2 of the
204
ordinary GNU General Public License has appeared, then you can specify
205
that version instead if you wish.)  Do not make any other change in
206
these notices.
207

208
  Once this change is made in a given copy, it is irreversible for
209
that copy, so the ordinary GNU General Public License applies to all
210
subsequent copies and derivative works made from that copy.
211

212
  This option is useful when you wish to copy part of the code of
213
the Library into a program that is not a library.
214

215
  4. You may copy and distribute the Library (or a portion or
216
derivative of it, under Section 2) in object code or executable form
217
under the terms of Sections 1 and 2 above provided that you accompany
218
it with the complete corresponding machine-readable source code, which
219
must be distributed under the terms of Sections 1 and 2 above on a
220
medium customarily used for software interchange.
221

222
  If distribution of object code is made by offering access to copy
223
from a designated place, then offering equivalent access to copy the
224
source code from the same place satisfies the requirement to
225
distribute the source code, even though third parties are not
226
compelled to copy the source along with the object code.
227

228
  5. A program that contains no derivative of any portion of the
229
Library, but is designed to work with the Library by being compiled or
230
linked with it, is called a "work that uses the Library".  Such a
231
work, in isolation, is not a derivative work of the Library, and
232
therefore falls outside the scope of this License.
233

234
  However, linking a "work that uses the Library" with the Library
235
creates an executable that is a derivative of the Library (because it
236
contains portions of the Library), rather than a "work that uses the
237
library".  The executable is therefore covered by this License.
238
Section 6 states terms for distribution of such executables.
239

240
  When a "work that uses the Library" uses material from a header file
241
that is part of the Library, the object code for the work may be a
242
derivative work of the Library even though the source code is not.
243
Whether this is true is especially significant if the work can be
244
linked without the Library, or if the work is itself a library.  The
245
threshold for this to be true is not precisely defined by law.
246

247
  If such an object file uses only numerical parameters, data
248
structure layouts and accessors, and small macros and small inline
249
functions (ten lines or less in length), then the use of the object
250
file is unrestricted, regardless of whether it is legally a derivative
251
work.  (Executables containing this object code plus portions of the
252
Library will still fall under Section 6.)
253

254
  Otherwise, if the work is a derivative of the Library, you may
255
distribute the object code for the work under the terms of Section 6.
256
Any executables containing that work also fall under Section 6,
257
whether or not they are linked directly with the Library itself.
258

259
  6. As an exception to the Sections above, you may also compile or
260
link a "work that uses the Library" with the Library to produce a
261
work containing portions of the Library, and distribute that work
262
under terms of your choice, provided that the terms permit
263
modification of the work for the customer's own use and reverse
264
engineering for debugging such modifications.
265

266
  You must give prominent notice with each copy of the work that the
267
Library is used in it and that the Library and its use are covered by
268
this License.  You must supply a copy of this License.  If the work
269
during execution displays copyright notices, you must include the
270
copyright notice for the Library among them, as well as a reference
271
directing the user to the copy of this License.  Also, you must do one
272
of these things:
273

274
    a) Accompany the work with the complete corresponding
275
    machine-readable source code for the Library including whatever
276
    changes were used in the work (which must be distributed under
277
    Sections 1 and 2 above); and, if the work is an executable linked
278
    with the Library, with the complete machine-readable "work that
279
    uses the Library", as object code and/or source code, so that the
280
    user can modify the Library and then relink to produce a modified
281
    executable containing the modified Library.  (It is understood
282
    that the user who changes the contents of definitions files in the
283
    Library will not necessarily be able to recompile the application
284
    to use the modified definitions.)
285

286
    b) Accompany the work with a written offer, valid for at
287
    least three years, to give the same user the materials
288
    specified in Subsection 6a, above, for a charge no more
289
    than the cost of performing this distribution.
290

291
    c) If distribution of the work is made by offering access to copy
292
    from a designated place, offer equivalent access to copy the above
293
    specified materials from the same place.
294

295
    d) Verify that the user has already received a copy of these
296
    materials or that you have already sent this user a copy.
297

298
  For an executable, the required form of the "work that uses the
299
Library" must include any data and utility programs needed for
300
reproducing the executable from it.  However, as a special exception,
301
the source code distributed need not include anything that is normally
302
distributed (in either source or binary form) with the major
303
components (compiler, kernel, and so on) of the operating system on
304
which the executable runs, unless that component itself accompanies
305
the executable.
306

307
  It may happen that this requirement contradicts the license
308
restrictions of other proprietary libraries that do not normally
309
accompany the operating system.  Such a contradiction means you cannot
310
use both them and the Library together in an executable that you
311
distribute.
312

313
  7. You may place library facilities that are a work based on the
314
Library side-by-side in a single library together with other library
315
facilities not covered by this License, and distribute such a combined
316
library, provided that the separate distribution of the work based on
317
the Library and of the other library facilities is otherwise
318
permitted, and provided that you do these two things:
319

320
    a) Accompany the combined library with a copy of the same work
321
    based on the Library, uncombined with any other library
322
    facilities.  This must be distributed under the terms of the
323
    Sections above.
324

325
    b) Give prominent notice with the combined library of the fact
326
    that part of it is a work based on the Library, and explaining
327
    where to find the accompanying uncombined form of the same work.
328

329
  8. You may not copy, modify, sublicense, link with, or distribute
330
the Library except as expressly provided under this License.  Any
331
attempt otherwise to copy, modify, sublicense, link with, or
332
distribute the Library is void, and will automatically terminate your
333
rights under this License.  However, parties who have received copies,
334
or rights, from you under this License will not have their licenses
335
terminated so long as such parties remain in full compliance.
336

337
  9. You are not required to accept this License, since you have not
338
signed it.  However, nothing else grants you permission to modify or
339
distribute the Library or its derivative works.  These actions are
340
prohibited by law if you do not accept this License.  Therefore, by
341
modifying or distributing the Library (or any work based on the
342
Library), you indicate your acceptance of this License to do so, and
343
all its terms and conditions for copying, distributing or modifying
344
the Library or works based on it.
345

346
  10. Each time you redistribute the Library (or any work based on the
347
Library), the recipient automatically receives a license from the
348
original licensor to copy, distribute, link with or modify the Library
349
subject to these terms and conditions.  You may not impose any further
350
restrictions on the recipients' exercise of the rights granted herein.
351
You are not responsible for enforcing compliance by third parties to
352
this License.
353

354
  11. If, as a consequence of a court judgment or allegation of patent
355
infringement or for any other reason (not limited to patent issues),
356
conditions are imposed on you (whether by court order, agreement or
357
otherwise) that contradict the conditions of this License, they do not
358
excuse you from the conditions of this License.  If you cannot
359
distribute so as to satisfy simultaneously your obligations under this
360
License and any other pertinent obligations, then as a consequence you
361
may not distribute the Library at all.  For example, if a patent
362
license would not permit royalty-free redistribution of the Library by
363
all those who receive copies directly or indirectly through you, then
364
the only way you could satisfy both it and this License would be to
365
refrain entirely from distribution of the Library.
366

367
If any portion of this section is held invalid or unenforceable under any
368
particular circumstance, the balance of the section is intended to apply,
369
and the section as a whole is intended to apply in other circumstances.
370

371
It is not the purpose of this section to induce you to infringe any
372
patents or other property right claims or to contest validity of any
373
such claims; this section has the sole purpose of protecting the
374
integrity of the free software distribution system which is
375
implemented by public license practices.  Many people have made
376
generous contributions to the wide range of software distributed
377
through that system in reliance on consistent application of that
378
system; it is up to the author/donor to decide if he or she is willing
379
to distribute software through any other system and a licensee cannot
380
impose that choice.
381

382
This section is intended to make thoroughly clear what is believed to
383
be a consequence of the rest of this License.
384

385
  12. If the distribution and/or use of the Library is restricted in
386
certain countries either by patents or by copyrighted interfaces, the
387
original copyright holder who places the Library under this License may add
388
an explicit geographical distribution limitation excluding those countries,
389
so that distribution is permitted only in or among countries not thus
390
excluded.  In such case, this License incorporates the limitation as if
391
written in the body of this License.
392

393
  13. The Free Software Foundation may publish revised and/or new
394
versions of the Library General Public License from time to time.
395
Such new versions will be similar in spirit to the present version,
396
but may differ in detail to address new problems or concerns.
397

398
Each version is given a distinguishing version number.  If the Library
399
specifies a version number of this License which applies to it and
400
"any later version", you have the option of following the terms and
401
conditions either of that version or of any later version published by
402
the Free Software Foundation.  If the Library does not specify a
403
license version number, you may choose any version ever published by
404
the Free Software Foundation.
405

406
  14. If you wish to incorporate parts of the Library into other free
407
programs whose distribution conditions are incompatible with these,
408
write to the author to ask for permission.  For software which is
409
copyrighted by the Free Software Foundation, write to the Free
410
Software Foundation; we sometimes make exceptions for this.  Our
411
decision will be guided by the two goals of preserving the free status
412
of all derivatives of our free software and of promoting the sharing
413
and reuse of software generally.
414

415
			    NO WARRANTY
416

417
  15. BECAUSE THE LIBRARY IS LICENSED FREE OF CHARGE, THERE IS NO
418
WARRANTY FOR THE LIBRARY, TO THE EXTENT PERMITTED BY APPLICABLE LAW.
419
EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR
420
OTHER PARTIES PROVIDE THE LIBRARY "AS IS" WITHOUT WARRANTY OF ANY
421
KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE
422
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
423
PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE
424
LIBRARY IS WITH YOU.  SHOULD THE LIBRARY PROVE DEFECTIVE, YOU ASSUME
425
THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
426

427
  16. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
428
WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY
429
AND/OR REDISTRIBUTE THE LIBRARY AS PERMITTED ABOVE, BE LIABLE TO YOU
430
FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR
431
CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE
432
LIBRARY (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
433
RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
434
FAILURE OF THE LIBRARY TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF
435
SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
436
DAMAGES.
437

438
		     END OF TERMS AND CONDITIONS
439
          How to Apply These Terms to Your New Libraries
440

441
  If you develop a new library, and you want it to be of the greatest
442
possible use to the public, we recommend making it free software that
443
everyone can redistribute and change.  You can do so by permitting
444
redistribution under these terms (or, alternatively, under the terms of the
445
ordinary General Public License).
446

447
  To apply these terms, attach the following notices to the library.  It is
448
safest to attach them to the start of each source file to most effectively
449
convey the exclusion of warranty; and each file should have at least the
450
"copyright" line and a pointer to where the full notice is found.
451

452
    <one line to give the library's name and a brief idea of what it does.>
453
    Copyright (C) <year>  <name of author>
454

455
    This library is free software; you can redistribute it and/or
456
    modify it under the terms of the GNU Lesser General Public
457
    License as published by the Free Software Foundation; either
458
    version 2 of the License, or (at your option) any later version.
459

460
    This library is distributed in the hope that it will be useful,
461
    but WITHOUT ANY WARRANTY; without even the implied warranty of
462
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
463
    Lesser General Public License for more details.
464

465
    You should have received a copy of the GNU Lesser General Public
466
    License along with this library; if not, write to the Free Software
467
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
468

469
Also add information on how to contact you by electronic and paper mail.
470

471
You should also get your employer (if you work as a programmer) or your
472
school, if any, to sign a "copyright disclaimer" for the library, if
473
necessary.  Here is a sample; alter the names:
474

475
  Yoyodyne, Inc., hereby disclaims all copyright interest in the
476
  library `Frob' (a library for tweaking knobs) written by James Random Hacker.
477

478
  <signature of Ty Coon>, 1 April 1990
479
  Ty Coon, President of Vice
480

481
That's all there is to it!
482