1 GNU GENERAL PUBLIC LICENSE
4 Copyright (C) 1989, 1991 Free Software Foundation, Inc.
5 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
7 Everyone is permitted to copy and distribute verbatim copies of this
8 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
32 you 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,
41 and (2) offer you this license which gives you legal permission to
42 copy, 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,
47 we want its recipients to know that what they have is not the
48 original, so that any problems introduced by others will not reflect
49 on the original authors' reputations.
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
58 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 Program
78 (independent of having been made by running the Program). Whether
79 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
93 2. You may modify your copy or copies of the Program or any portion
94 of it, thus forming a work based on the Program, and copy and
95 distribute such modifications or work under the terms of Section 1
96 above, provided that you also meet all of these conditions:
98 a) You must cause the modified files to carry prominent notices
99 stating that you changed the files and the date of any change.
101 b) You must cause any work that you distribute or publish, that in
102 whole or in part contains or is derived from the Program or any
103 part thereof, to be licensed as a whole at no charge to all third
104 parties under the terms of this License.
106 c) If the modified program normally reads commands interactively
107 when run, you must cause it, when started running for such
108 interactive use in the most ordinary way, to print or display an
109 announcement including an appropriate copyright notice and a
110 notice that there is no warranty (or else, saying that you provide
111 a warranty) and that users may redistribute the program under
112 these conditions, and telling the user how to view a copy of this
113 License. (Exception: if the Program itself is interactive but
114 does not normally print such an announcement, your work based on
115 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
128 Thus, it is not the intent of this section to claim rights or contest
129 your rights to work written entirely by you; rather, the intent is to
130 exercise the right to control the distribution of derivative or
131 collective works based on the Program.
133 In addition, mere aggregation of another work not based on the Program
134 with the Program (or with a work based on the Program) on a volume of
135 a storage or distribution medium does not bring the other work under
136 the scope of this License.
138 3. You may copy and distribute the Program (or a work based on it,
139 under Section 2) in object code or executable form under the terms of
140 Sections 1 and 2 above provided that you also do one of the following:
142 a) Accompany it with the complete corresponding machine-readable
143 source code, which must be distributed under the terms of Sections
144 1 and 2 above on a medium customarily used for software
147 b) Accompany it with a written offer, valid for at least three
148 years, to give any third party, for a charge no more than your
149 cost of physically performing source distribution, a complete
150 machine-readable copy of the corresponding source code, to be
151 distributed under the terms of Sections 1 and 2 above on a medium
152 customarily used for software interchange; or,
154 c) Accompany it with the information you received as to the offer
155 to distribute corresponding source code. (This alternative is
156 allowed only for noncommercial distribution and only if you
157 received the program in object code or executable form with such
158 an offer, in accord with Subsection b above.)
160 The source code for a work means the preferred form of the work for
161 making modifications to it. For an executable work, complete source
162 code means all the source code for all modules it contains, plus any
163 associated interface definition files, plus the scripts used to
164 control compilation and installation of the executable. However, as a
165 special exception, the source code distributed need not include
166 anything that is normally distributed (in either source or binary
167 form) with the major components (compiler, kernel, and so on) of the
168 operating system on which the executable runs, unless that component
169 itself accompanies the executable.
171 If distribution of executable or object code is made by offering
172 access to copy from a designated place, then offering equivalent
173 access to copy the source code from the same place counts as
174 distribution of the source code, even though third parties are not
175 compelled to copy the source along with the object code.
177 4. You may not copy, modify, sublicense, or distribute the Program
178 except as expressly provided under this License. Any attempt
179 otherwise to copy, modify, sublicense or distribute the Program is
180 void, and will automatically terminate your rights under this License.
181 However, parties who have received copies, or rights, from you under
182 this License will not have their licenses terminated so long as such
183 parties remain in full compliance.
185 5. You are not required to accept this License, since you have not
186 signed it. However, nothing else grants you permission to modify or
187 distribute the Program or its derivative works. These actions are
188 prohibited by law if you do not accept this License. Therefore, by
189 modifying or distributing the Program (or any work based on the
190 Program), you indicate your acceptance of this License to do so, and
191 all its terms and conditions for copying, distributing or modifying
192 the Program or works based on it.
194 6. Each time you redistribute the Program (or any work based on the
195 Program), the recipient automatically receives a license from the
196 original licensor to copy, distribute or modify the Program subject to
197 these terms and conditions. You may not impose any further
198 restrictions on the recipients' exercise of the rights granted herein.
199 You are not responsible for enforcing compliance by third parties to
202 7. If, as a consequence of a court judgment or allegation of patent
203 infringement or for any other reason (not limited to patent issues),
204 conditions are imposed on you (whether by court order, agreement or
205 otherwise) that contradict the conditions of this License, they do not
206 excuse you from the conditions of this License. If you cannot
207 distribute so as to satisfy simultaneously your obligations under this
208 License and any other pertinent obligations, then as a consequence you
209 may not distribute the Program at all. For example, if a patent
210 license would not permit royalty-free redistribution of the Program by
211 all those who receive copies directly or indirectly through you, then
212 the only way you could satisfy both it and this License would be to
213 refrain entirely from distribution of the Program.
215 If any portion of this section is held invalid or unenforceable under
216 any particular circumstance, the balance of the section is intended to
217 apply and the section as a whole is intended to apply in other
220 It is not the purpose of this section to induce you to infringe any
221 patents or other property right claims or to contest validity of any
222 such claims; this section has the sole purpose of protecting the
223 integrity of the free software distribution system, which is
224 implemented by public license practices. Many people have made
225 generous contributions to the wide range of software distributed
226 through that system in reliance on consistent application of that
227 system; it is up to the author/donor to decide if he or she is willing
228 to distribute software through any other system and a licensee cannot
231 This section is intended to make thoroughly clear what is believed to
232 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
243 versions of the General Public License from time to time. Such new
244 versions will be similar in spirit to the present version, but may
245 differ in detail to 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
249 "any later version", you have the option of following the terms and
250 conditions either of that version or of any later version published by
251 the Free Software Foundation. If the Program does not specify a
252 version number of this License, you may choose any version ever
253 published by the Free Software Foundation.
255 10. If you wish to incorporate parts of the Program into other free
256 programs whose distribution conditions are different, write to the
257 author to ask for permission. For software which is copyrighted by
258 the Free Software Foundation, write to the Free Software Foundation;
259 we sometimes make exceptions for this. Our decision will be guided by
260 the two goals of preserving the free status of all derivatives of our
261 free software and of promoting the sharing and reuse of software
266 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO
267 WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.
268 EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR
269 OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY
270 KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE
271 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
272 PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE
273 PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME
274 THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
276 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
277 WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY
278 AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU
279 FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR
280 CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE
281 PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
282 RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
283 FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF
284 SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
287 END OF TERMS AND CONDITIONS
289 How to Apply These Terms to Your New Programs
291 If you develop a new program, and you want it to be of the greatest
292 possible use to the public, the best way to achieve this is to make it
293 free software which everyone can redistribute and change under these
296 To do so, attach the following notices to the program. It is safest
297 to attach them to the start of each source file to most effectively
298 convey the exclusion of warranty; and each file should have at least
299 the "copyright" line and a pointer to where the full notice is found.
301 <one line to give the program's name and a brief idea of what it does.>
302 Copyright (C) <year> <name of author>
304 This program is free software; you can redistribute it and/or
305 modify it under the terms of the GNU General Public License as
306 published by the Free Software Foundation; either version 2 of the
307 License, or (at your option) any later version.
309 This program is distributed in the hope that it will be useful,
310 but WITHOUT ANY WARRANTY; without even the implied warranty of
311 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
312 General Public License for more details.
314 You should have received a copy of the GNU General Public License
315 along with this program; if not, write to the Free Software
316 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
320 Also add information on how to contact you by electronic and paper mail.
322 If the program is interactive, make it output a short notice like
323 this when it starts in an interactive mode:
325 Gnomovision version 69, Copyright (C) year name of author
326 Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
327 This is free software, and you are welcome to redistribute it
328 under certain conditions; type `show c' for details.
330 The hypothetical commands `show w' and `show c' should show the
331 appropriate parts of the General Public License. Of course, the
332 commands you use may be called something other than `show w' and `show
333 c'; they could even be mouse-clicks or menu items--whatever suits your
336 You should also get your employer (if you work as a programmer) or
337 your school, if any, to sign a "copyright disclaimer" for the program,
338 if necessary. Here is a sample; alter the names:
340 Yoyodyne, Inc., hereby disclaims all copyright interest in the program
341 `Gnomovision' (which makes passes at compilers) written by James Hacker.
343 <signature of Ty Coon>, 1 April 1989
344 Ty Coon, President of Vice
346 This General Public License does not permit incorporating your program
347 into proprietary programs. If your program is a subroutine library,
348 you may consider it more useful to permit linking proprietary
349 applications with the library. If this is what you want to do, use
350 the GNU Library General Public License instead of this License.