1 GNU GENERAL PUBLIC LICENSE
4 Copyright (C) 1989, 1991 Free Software Foundation, Inc.
5 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
7 Everyone is permitted to copy and distribute verbatim copies
8 of this license document, but changing it is not allowed.
12 The licenses for most software are designed to take away your
13 freedom to share and change it. By contrast, the GNU General Public
14 License is intended to guarantee your freedom to share and change free
15 software--to make sure the software is free for all its users. This
16 General Public License applies to most of the Free Software
17 Foundation's software and to any other program whose authors commit to
18 using it. (Some other Free Software Foundation software is covered by
19 the GNU Library General Public License instead.) You can apply it to
22 When we speak of free software, we are referring to freedom, not
23 price. Our General Public Licenses are designed to make sure that you
24 have the freedom to distribute copies of free software (and charge for
25 this service if you wish), that you receive source code or can get it
26 if you want it, that you can change the software or use pieces of it
27 in new free programs; and that you know you can do these things.
29 To protect your rights, we need to make restrictions that forbid
30 anyone to deny you these rights or to ask you to surrender the rights.
31 These restrictions translate to certain responsibilities for you if you
32 distribute copies of the software, or if you modify it.
34 For example, if you distribute copies of such a program, whether
35 gratis or for a fee, you must give the recipients all the rights that
36 you have. You must make sure that they, too, receive or can get the
37 source code. And you must show them these terms so they know their
40 We protect your rights with two steps: (1) copyright the software, and
41 (2) offer you this license which gives you legal permission to copy,
42 distribute and/or modify the software.
44 Also, for each author's protection and ours, we want to make certain
45 that everyone understands that there is no warranty for this free
46 software. If the software is modified by someone else and passed on, we
47 want its recipients to know that what they have is not the original, so
48 that any problems introduced by others will not reflect on the original
51 Finally, any free program is threatened constantly by software
52 patents. We wish to avoid the danger that redistributors of a free
53 program will individually obtain patent licenses, in effect making the
54 program proprietary. To prevent this, we have made it clear that any
55 patent must be licensed for everyone's free use or not licensed at all.
57 The precise terms and conditions for copying, distribution and
61 GNU GENERAL PUBLIC LICENSE
62 TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
64 0. This License applies to any program or other work which contains
65 a notice placed by the copyright holder saying it may be distributed
66 under the terms of this General Public License. The "Program", below,
67 refers to any such program or work, and a "work based on the Program"
68 means either the Program or any derivative work under copyright law:
69 that is to say, a work containing the Program or a portion of it,
70 either verbatim or with modifications and/or translated into another
71 language. (Hereinafter, translation is included without limitation in
72 the term "modification".) Each licensee is addressed as "you".
74 Activities other than copying, distribution and modification are not
75 covered by this License; they are outside its scope. The act of
76 running the Program is not restricted, and the output from the Program
77 is covered only if its contents constitute a work based on the
78 Program (independent of having been made by running the Program).
79 Whether that is true depends on what the Program does.
81 1. You may copy and distribute verbatim copies of the Program's
82 source code as you receive it, in any medium, provided that you
83 conspicuously and appropriately publish on each copy an appropriate
84 copyright notice and disclaimer of warranty; keep intact all the
85 notices that refer to this License and to the absence of any warranty;
86 and give any other recipients of the Program a copy of this License
87 along with the Program.
89 You may charge a fee for the physical act of transferring a copy, and
90 you may at your option offer warranty protection in exchange for a fee.
92 2. You may modify your copy or copies of the Program or any portion
93 of it, thus forming a work based on the Program, and copy and
94 distribute such modifications or work under the terms of Section 1
95 above, provided that you also meet all of these conditions:
97 a) You must cause the modified files to carry prominent notices
98 stating that you changed the files and the date of any change.
100 b) You must cause any work that you distribute or publish, that in
101 whole or in part contains or is derived from the Program or any
102 part thereof, to be licensed as a whole at no charge to all third
103 parties under the terms of this License.
105 c) If the modified program normally reads commands interactively
106 when run, you must cause it, when started running for such
107 interactive use in the most ordinary way, to print or display an
108 announcement including an appropriate copyright notice and a
109 notice that there is no warranty (or else, saying that you provide
110 a warranty) and that users may redistribute the program under
111 these conditions, and telling the user how to view a copy of this
112 License. (Exception: if the Program itself is interactive but
113 does not normally print such an announcement, your work based on
114 the Program is not required to print an announcement.)
117 These requirements apply to the modified work as a whole. If
118 identifiable sections of that work are not derived from the Program,
119 and can be reasonably considered independent and separate works in
120 themselves, then this License, and its terms, do not apply to those
121 sections when you distribute them as separate works. But when you
122 distribute the same sections as part of a whole which is a work based
123 on the Program, the distribution of the whole must be on the terms of
124 this License, whose permissions for other licensees extend to the
125 entire whole, and thus to each and every part regardless of who wrote it.
127 Thus, it is not the intent of this section to claim rights or contest
128 your rights to work written entirely by you; rather, the intent is to
129 exercise the right to control the distribution of derivative or
130 collective works based on the Program.
132 In addition, mere aggregation of another work not based on the Program
133 with the Program (or with a work based on the Program) on a volume of
134 a storage or distribution medium does not bring the other work under
135 the scope of this License.
137 3. You may copy and distribute the Program (or a work based on it,
138 under Section 2) in object code or executable form under the terms of
139 Sections 1 and 2 above provided that you also do one of the following:
141 a) Accompany it with the complete corresponding machine-readable
142 source code, which must be distributed under the terms of Sections
143 1 and 2 above on a medium customarily used for software interchange; or,
145 b) Accompany it with a written offer, valid for at least three
146 years, to give any third party, for a charge no more than your
147 cost of physically performing source distribution, a complete
148 machine-readable copy of the corresponding source code, to be
149 distributed under the terms of Sections 1 and 2 above on a medium
150 customarily used for software interchange; or,
152 c) Accompany it with the information you received as to the offer
153 to distribute corresponding source code. (This alternative is
154 allowed only for noncommercial distribution and only if you
155 received the program in object code or executable form with such
156 an offer, in accord with Subsection b above.)
158 The source code for a work means the preferred form of the work for
159 making modifications to it. For an executable work, complete source
160 code means all the source code for all modules it contains, plus any
161 associated interface definition files, plus the scripts used to
162 control compilation and installation of the executable. However, as a
163 special exception, the source code distributed need not include
164 anything that is normally distributed (in either source or binary
165 form) with the major components (compiler, kernel, and so on) of the
166 operating system on which the executable runs, unless that component
167 itself accompanies the executable.
169 If distribution of executable or object code is made by offering
170 access to copy from a designated place, then offering equivalent
171 access to copy the source code from the same place counts as
172 distribution of the source code, even though third parties are not
173 compelled to copy the source along with the object code.
176 4. You may not copy, modify, sublicense, or distribute the Program
177 except as expressly provided under this License. Any attempt
178 otherwise to copy, modify, sublicense or distribute the Program is
179 void, and will automatically terminate your rights under this License.
180 However, parties who have received copies, or rights, from you under
181 this License will not have their licenses terminated so long as such
182 parties remain in full compliance.
184 5. You are not required to accept this License, since you have not
185 signed it. However, nothing else grants you permission to modify or
186 distribute the Program or its derivative works. These actions are
187 prohibited by law if you do not accept this License. Therefore, by
188 modifying or distributing the Program (or any work based on the
189 Program), you indicate your acceptance of this License to do so, and
190 all its terms and conditions for copying, distributing or modifying
191 the Program or works based on it.
193 6. Each time you redistribute the Program (or any work based on the
194 Program), the recipient automatically receives a license from the
195 original licensor to copy, distribute or modify the Program subject to
196 these terms and conditions. You may not impose any further
197 restrictions on the recipients' exercise of the rights granted herein.
198 You are not responsible for enforcing compliance by third parties to
201 7. If, as a consequence of a court judgment or allegation of patent
202 infringement or for any other reason (not limited to patent issues),
203 conditions are imposed on you (whether by court order, agreement or
204 otherwise) that contradict the conditions of this License, they do not
205 excuse you from the conditions of this License. If you cannot
206 distribute so as to satisfy simultaneously your obligations under this
207 License and any other pertinent obligations, then as a consequence you
208 may not distribute the Program at all. For example, if a patent
209 license would not permit royalty-free redistribution of the Program by
210 all those who receive copies directly or indirectly through you, then
211 the only way you could satisfy both it and this License would be to
212 refrain entirely from distribution of the Program.
214 If any portion of this section is held invalid or unenforceable under
215 any particular circumstance, the balance of the section is intended to
216 apply and the section as a whole is intended to apply in other
219 It is not the purpose of this section to induce you to infringe any
220 patents or other property right claims or to contest validity of any
221 such claims; this section has the sole purpose of protecting the
222 integrity of the free software distribution system, which is
223 implemented by public license practices. Many people have made
224 generous contributions to the wide range of software distributed
225 through that system in reliance on consistent application of that
226 system; it is up to the author/donor to decide if he or she is willing
227 to distribute software through any other system and a licensee cannot
230 This section is intended to make thoroughly clear what is believed to
231 be a consequence of the rest of this License.
234 8. If the distribution and/or use of the Program is restricted in
235 certain countries either by patents or by copyrighted interfaces, the
236 original copyright holder who places the Program under this License
237 may add an explicit geographical distribution limitation excluding
238 those countries, so that distribution is permitted only in or among
239 countries not thus excluded. In such case, this License incorporates
240 the limitation as if written in the body of this License.
242 9. The Free Software Foundation may publish revised and/or new versions
243 of the General Public License from time to time. Such new versions will
244 be similar in spirit to the present version, but may differ in detail to
245 address new problems or concerns.
247 Each version is given a distinguishing version number. If the Program
248 specifies a version number of this License which applies to it and "any
249 later version", you have the option of following the terms and conditions
250 either of that version or of any later version published by the Free
251 Software Foundation. If the Program does not specify a version number of
252 this License, you may choose any version ever published by the Free Software
255 10. If you wish to incorporate parts of the Program into other free
256 programs whose distribution conditions are different, write to the author
257 to ask for permission. For software which is copyrighted by the Free
258 Software Foundation, write to the Free Software Foundation; we sometimes
259 make exceptions for this. Our decision will be guided by the two goals
260 of preserving the free status of all derivatives of our free software and
261 of promoting the sharing and reuse of software generally.
265 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
266 FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
267 OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
268 PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
269 OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
270 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE ENTIRE RISK AS
271 TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE
272 PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
273 REPAIR OR CORRECTION.
275 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
276 WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
277 REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
278 INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
279 OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
280 TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
281 YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
282 PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
283 POSSIBILITY OF SUCH DAMAGES.
285 END OF TERMS AND CONDITIONS
288 Appendix: How to Apply These Terms to Your New Programs
290 If you develop a new program, and you want it to be of the greatest
291 possible use to the public, the best way to achieve this is to make it
292 free software which everyone can redistribute and change under these terms.
294 To do so, attach the following notices to the program. It is safest
295 to attach them to the start of each source file to most effectively
296 convey the exclusion of warranty; and each file should have at least
297 the "copyright" line and a pointer to where the full notice is found.
299 <one line to give the program's name and a brief idea of what it does.>
300 Copyright (C) <year> <name of author>
302 This program is free software; you can redistribute it and/or modify
303 it under the terms of the GNU General Public License as published by
304 the Free Software Foundation; either version 2 of the License, or
305 (at your option) any later version.
307 This program is distributed in the hope that it will be useful,
308 but WITHOUT ANY WARRANTY; without even the implied warranty of
309 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
310 GNU General Public License for more details.
312 You should have received a copy of the GNU General Public License
313 along with this program; if not, write to the Free Software
314 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
316 Also add information on how to contact you by electronic and paper mail.
318 If the program is interactive, make it output a short notice like this
319 when it starts in an interactive mode:
321 Gnomovision version 69, Copyright (C) year name of author
322 Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
323 This is free software, and you are welcome to redistribute it
324 under certain conditions; type `show c' for details.
326 The hypothetical commands `show w' and `show c' should show the appropriate
327 parts of the General Public License. Of course, the commands you use may
328 be called something other than `show w' and `show c'; they could even be
329 mouse-clicks or menu items--whatever suits your program.
331 You should also get your employer (if you work as a programmer) or your
332 school, if any, to sign a "copyright disclaimer" for the program, if
333 necessary. Here is a sample; alter the names:
335 Yoyodyne, Inc., hereby disclaims all copyright interest in the program
336 `Gnomovision' (which makes passes at compilers) written by James Hacker.
338 <signature of Ty Coon>, 1 April 1989
339 Ty Coon, President of Vice
341 This General Public License does not permit incorporating your program into
342 proprietary programs. If your program is a subroutine library, you may
343 consider it more useful to permit linking proprietary applications with the
344 library. If this is what you want to do, use the GNU Library General
345 Public License instead of this License.