CoCalc Public Fileswww / onhand / fton / COPYING
Author: William A. Stein
1		    GNU GENERAL PUBLIC LICENSE
2		       Version 2, June 1991
3
4 Copyright (C) 1989, 1991 Free Software Foundation, Inc.
5                       59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
6 Everyone is permitted to copy and distribute verbatim copies
7 of this license document, but changing it is not allowed.
8
9			    Preamble
10
11  The licenses for most software are designed to take away your
12freedom to share and change it.  By contrast, the GNU General Public
13License is intended to guarantee your freedom to share and change free
14software--to make sure the software is free for all its users.  This
15General Public License applies to most of the Free Software
16Foundation's software and to any other program whose authors commit to
17using it.  (Some other Free Software Foundation software is covered by
18the GNU Library General Public License instead.)  You can apply it to
19your programs, too.
20
21  When we speak of free software, we are referring to freedom, not
22price.  Our General Public Licenses are designed to make sure that you
23have the freedom to distribute copies of free software (and charge for
24this service if you wish), that you receive source code or can get it
25if you want it, that you can change the software or use pieces of it
26in new free programs; and that you know you can do these things.
27
28  To protect your rights, we need to make restrictions that forbid
29anyone to deny you these rights or to ask you to surrender the rights.
30These restrictions translate to certain responsibilities for you if you
31distribute copies of the software, or if you modify it.
32
33  For example, if you distribute copies of such a program, whether
34gratis or for a fee, you must give the recipients all the rights that
35you have.  You must make sure that they, too, receive or can get the
36source code.  And you must show them these terms so they know their
37rights.
38
39  We protect your rights with two steps: (1) copyright the software, and
40(2) offer you this license which gives you legal permission to copy,
41distribute and/or modify the software.
42
43  Also, for each author's protection and ours, we want to make certain
44that everyone understands that there is no warranty for this free
45software.  If the software is modified by someone else and passed on, we
46want its recipients to know that what they have is not the original, so
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49
50  Finally, any free program is threatened constantly by software
51patents.  We wish to avoid the danger that redistributors of a free
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53program proprietary.  To prevent this, we have made it clear that any
54patent must be licensed for everyone's free use or not licensed at all.
55
56  The precise terms and conditions for copying, distribution and
57modification follow.
58
59		    GNU GENERAL PUBLIC LICENSE
60   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
61
62  0. This License applies to any program or other work which contains
63a notice placed by the copyright holder saying it may be distributed
64under the terms of this General Public License.  The "Program", below,
65refers to any such program or work, and a "work based on the Program"
66means either the Program or any derivative work under copyright law:
67that is to say, a work containing the Program or a portion of it,
68either verbatim or with modifications and/or translated into another
69language.  (Hereinafter, translation is included without limitation in
70the term "modification".)  Each licensee is addressed as "you".
71
72Activities other than copying, distribution and modification are not
73covered by this License; they are outside its scope.  The act of
74running the Program is not restricted, and the output from the Program
75is covered only if its contents constitute a work based on the
76Program (independent of having been made by running the Program).
77Whether that is true depends on what the Program does.
78
79  1. You may copy and distribute verbatim copies of the Program's
80source code as you receive it, in any medium, provided that you
81conspicuously and appropriately publish on each copy an appropriate
82copyright notice and disclaimer of warranty; keep intact all the
83notices that refer to this License and to the absence of any warranty;
84and give any other recipients of the Program a copy of this License
85along with the Program.
86
87You may charge a fee for the physical act of transferring a copy, and
88you may at your option offer warranty protection in exchange for a fee.
89
90  2. You may modify your copy or copies of the Program or any portion
91of it, thus forming a work based on the Program, and copy and
92distribute such modifications or work under the terms of Section 1
93above, provided that you also meet all of these conditions:
94
95    a) You must cause the modified files to carry prominent notices
96    stating that you changed the files and the date of any change.
97
98    b) You must cause any work that you distribute or publish, that in
99    whole or in part contains or is derived from the Program or any
100    part thereof, to be licensed as a whole at no charge to all third
101    parties under the terms of this License.
102
103    c) If the modified program normally reads commands interactively
104    when run, you must cause it, when started running for such
105    interactive use in the most ordinary way, to print or display an
106    announcement including an appropriate copyright notice and a
107    notice that there is no warranty (or else, saying that you provide
108    a warranty) and that users may redistribute the program under
109    these conditions, and telling the user how to view a copy of this
110    License.  (Exception: if the Program itself is interactive but
111    does not normally print such an announcement, your work based on
112    the Program is not required to print an announcement.)
113
114These requirements apply to the modified work as a whole.  If
115identifiable sections of that work are not derived from the Program,
116and can be reasonably considered independent and separate works in
117themselves, then this License, and its terms, do not apply to those
118sections when you distribute them as separate works.  But when you
119distribute the same sections as part of a whole which is a work based
120on the Program, the distribution of the whole must be on the terms of
121this License, whose permissions for other licensees extend to the
122entire whole, and thus to each and every part regardless of who wrote it.
123
124Thus, it is not the intent of this section to claim rights or contest
125your rights to work written entirely by you; rather, the intent is to
126exercise the right to control the distribution of derivative or
127collective works based on the Program.
128
129In addition, mere aggregation of another work not based on the Program
130with the Program (or with a work based on the Program) on a volume of
131a storage or distribution medium does not bring the other work under
132the scope of this License.
133
134  3. You may copy and distribute the Program (or a work based on it,
135under Section 2) in object code or executable form under the terms of
136Sections 1 and 2 above provided that you also do one of the following:
137
138    a) Accompany it with the complete corresponding machine-readable
139    source code, which must be distributed under the terms of Sections
140    1 and 2 above on a medium customarily used for software interchange; or,
141
142    b) Accompany it with a written offer, valid for at least three
143    years, to give any third party, for a charge no more than your
144    cost of physically performing source distribution, a complete
145    machine-readable copy of the corresponding source code, to be
146    distributed under the terms of Sections 1 and 2 above on a medium
147    customarily used for software interchange; or,
148
149    c) Accompany it with the information you received as to the offer
150    to distribute corresponding source code.  (This alternative is
151    allowed only for noncommercial distribution and only if you
152    received the program in object code or executable form with such
153    an offer, in accord with Subsection b above.)
154
155The source code for a work means the preferred form of the work for
156making modifications to it.  For an executable work, complete source
157code means all the source code for all modules it contains, plus any
158associated interface definition files, plus the scripts used to
159control compilation and installation of the executable.  However, as a
160special exception, the source code distributed need not include
161anything that is normally distributed (in either source or binary
162form) with the major components (compiler, kernel, and so on) of the
163operating system on which the executable runs, unless that component
164itself accompanies the executable.
165
166If distribution of executable or object code is made by offering
167access to copy from a designated place, then offering equivalent
168access to copy the source code from the same place counts as
169distribution of the source code, even though third parties are not
170compelled to copy the source along with the object code.
171
172  4. You may not copy, modify, sublicense, or distribute the Program
173except as expressly provided under this License.  Any attempt
174otherwise to copy, modify, sublicense or distribute the Program is
175void, and will automatically terminate your rights under this License.
176However, parties who have received copies, or rights, from you under
177this License will not have their licenses terminated so long as such
178parties remain in full compliance.
179
180  5. You are not required to accept this License, since you have not
181signed it.  However, nothing else grants you permission to modify or
182distribute the Program or its derivative works.  These actions are
183prohibited by law if you do not accept this License.  Therefore, by
184modifying or distributing the Program (or any work based on the
185Program), you indicate your acceptance of this License to do so, and
186all its terms and conditions for copying, distributing or modifying
187the Program or works based on it.
188
189  6. Each time you redistribute the Program (or any work based on the
190Program), the recipient automatically receives a license from the
191original licensor to copy, distribute or modify the Program subject to
192these terms and conditions.  You may not impose any further
193restrictions on the recipients' exercise of the rights granted herein.
194You are not responsible for enforcing compliance by third parties to
195this License.
196
197  7. If, as a consequence of a court judgment or allegation of patent
198infringement or for any other reason (not limited to patent issues),
199conditions are imposed on you (whether by court order, agreement or
200otherwise) that contradict the conditions of this License, they do not
201excuse you from the conditions of this License.  If you cannot
202distribute so as to satisfy simultaneously your obligations under this
203License and any other pertinent obligations, then as a consequence you
204may not distribute the Program at all.  For example, if a patent
205license would not permit royalty-free redistribution of the Program by
206all those who receive copies directly or indirectly through you, then
207the only way you could satisfy both it and this License would be to
208refrain entirely from distribution of the Program.
209
210If any portion of this section is held invalid or unenforceable under
211any particular circumstance, the balance of the section is intended to
212apply and the section as a whole is intended to apply in other
213circumstances.
214
215It is not the purpose of this section to induce you to infringe any
216patents or other property right claims or to contest validity of any
217such claims; this section has the sole purpose of protecting the
218integrity of the free software distribution system, which is
219implemented by public license practices.  Many people have made
220generous contributions to the wide range of software distributed
221through that system in reliance on consistent application of that
222system; it is up to the author/donor to decide if he or she is willing
223to distribute software through any other system and a licensee cannot
224impose that choice.
225
226This section is intended to make thoroughly clear what is believed to
227be a consequence of the rest of this License.
228
229  8. If the distribution and/or use of the Program is restricted in
230certain countries either by patents or by copyrighted interfaces, the
231original copyright holder who places the Program under this License
232may add an explicit geographical distribution limitation excluding
233those countries, so that distribution is permitted only in or among
234countries not thus excluded.  In such case, this License incorporates
235the limitation as if written in the body of this License.
236
237  9. The Free Software Foundation may publish revised and/or new versions
238of the General Public License from time to time.  Such new versions will
239be similar in spirit to the present version, but may differ in detail to
240address new problems or concerns.
241
242Each version is given a distinguishing version number.  If the Program
243specifies a version number of this License which applies to it and "any
244later version", you have the option of following the terms and conditions
245either of that version or of any later version published by the Free
246Software Foundation.  If the Program does not specify a version number of
247this License, you may choose any version ever published by the Free Software
248Foundation.
249
250  10. If you wish to incorporate parts of the Program into other free
251programs whose distribution conditions are different, write to the author
252to ask for permission.  For software which is copyrighted by the Free
253Software Foundation, write to the Free Software Foundation; we sometimes
254make exceptions for this.  Our decision will be guided by the two goals
255of preserving the free status of all derivatives of our free software and
256of promoting the sharing and reuse of software generally.
257
258			    NO WARRANTY
259
260  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
261FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
262OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
263PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
264OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
265MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
266TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
267PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
268REPAIR OR CORRECTION.
269
270  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
271WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
272REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
273INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
274OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
275TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
276YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
277PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
278POSSIBILITY OF SUCH DAMAGES.
279
280		     END OF TERMS AND CONDITIONS
281
282	    How to Apply These Terms to Your New Programs
283
284  If you develop a new program, and you want it to be of the greatest
285possible use to the public, the best way to achieve this is to make it
286free software which everyone can redistribute and change under these terms.
287
288  To do so, attach the following notices to the program.  It is safest
289to attach them to the start of each source file to most effectively
290convey the exclusion of warranty; and each file should have at least
291the "copyright" line and a pointer to where the full notice is found.
292
293    <one line to give the program's name and a brief idea of what it does.>
294    Copyright (C) 19yy  <name of author>
295
296    This program is free software; you can redistribute it and/or modify
297    it under the terms of the GNU General Public License as published by
298    the Free Software Foundation; either version 2 of the License, or
299    (at your option) any later version.
300
301    This program is distributed in the hope that it will be useful,
302    but WITHOUT ANY WARRANTY; without even the implied warranty of
303    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
304    GNU General Public License for more details.
305
306    You should have received a copy of the GNU General Public License
307    along with this program; if not, write to the Free Software
308    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
309
310
311Also add information on how to contact you by electronic and paper mail.
312
313If the program is interactive, make it output a short notice like this
314when it starts in an interactive mode:
315
316    Gnomovision version 69, Copyright (C) 19yy name of author
317    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type show w'.
318    This is free software, and you are welcome to redistribute it
319    under certain conditions; type show c' for details.
320
321The hypothetical commands show w' and show c' should show the appropriate
322parts of the General Public License.  Of course, the commands you use may
323be called something other than show w' and show c'; they could even be
324mouse-clicks or menu items--whatever suits your program.
325
326You should also get your employer (if you work as a programmer) or your
327school, if any, to sign a "copyright disclaimer" for the program, if
328necessary.  Here is a sample; alter the names:
329
330  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
331  Gnomovision' (which makes passes at compilers) written by James Hacker.
332
333  <signature of Ty Coon>, 1 April 1989
334  Ty Coon, President of Vice
335
336This General Public License does not permit incorporating your program into
337proprietary programs.  If your program is a subroutine library, you may
338consider it more useful to permit linking proprietary applications with the
339library.  If this is what you want to do, use the GNU Library General
340Public License instead of this License.
341
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