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2<head>
3<title>The GNU General Public License</title>
4</head>
5<body bgcolor="#C0C0C0">
6
7<center>
8<h1>The GNU General Public License
9</h1>
10</center>
11</p>
12<center>
13<h2><a name="v2"><font face="arial, helvetica">
14Version 2, June 1991
15</font></a>
16</h2>
17</center>
18<address>
19&copy; Copyright 1989, 1991
20<a href="http://www.fsf.org/fsf/fsf.html">Free Software Foundation</a>, Inc.
21
22<br>
2359 Temple Place, Suite 330, Boston, MA  02111-1307  USA
24</address>
25<p>
26Everyone is permitted to copy and distribute verbatim copies
27of this license document, but changing it is not allowed.
28
29<h3>
30<center>
31			    Preamble
32</center>
33</h3>
34<p>
35  The licenses for most software are designed to take away your
36freedom to share and change it.  By contrast, the GNU General Public
37License is intended to guarantee your freedom to share and change free
38software--to make sure the software is free for all its users.  This
39General Public License applies to most of the Free Software
40Foundation's software and to any other program whose authors commit to
41using it.  (Some other Free Software Foundation software is covered by
42the GNU Library General Public License instead.)  You can apply it to
43your programs, too.
44<p>
45  When we speak of free software, we are referring to freedom, not
46price.  Our General Public Licenses are designed to make sure that you
47have the freedom to distribute copies of free software (and charge for
48this service if you wish), that you receive source code or can get it
49if you want it, that you can change the software or use pieces of it
50in new free programs; and that you know you can do these things.
51<p>
52  To protect your rights, we need to make restrictions that forbid
53anyone to deny you these rights or to ask you to surrender the rights.
54These restrictions translate to certain responsibilities for you if you
55distribute copies of the software, or if you modify it.
56<p>
57  For example, if you distribute copies of such a program, whether
58gratis or for a fee, you must give the recipients all the rights that
59you have.  You must make sure that they, too, receive or can get the
60source code.  And you must show them these terms so they know their
61rights.
62<p>
63  We protect your rights with two steps: (1) copyright the software, and
64(2) offer you this license which gives you legal permission to copy,
65distribute and/or modify the software.
66<p>
67  Also, for each author's protection and ours, we want to make certain
68that everyone understands that there is no warranty for this free
69software.  If the software is modified by someone else and passed on, we
70want its recipients to know that what they have is not the original, so
71that any problems introduced by others will not reflect on the original
72authors' reputations.
73<p>
74  Finally, any free program is threatened constantly by software
75patents.  We wish to avoid the danger that redistributors of a free
76program will individually obtain patent licenses, in effect making the
77program proprietary.  To prevent this, we have made it clear that any
78patent must be licensed for everyone's free use or not licensed at all.
79<p>
80  The precise terms and conditions for copying, distribution and
81modification follow.
82<p>
83<h3>
84<center>
85		    GNU GENERAL PUBLIC LICENSE
86<br>
87   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
88</center>
89</h3>
90<p>
91  0. This License applies to any program or other work which contains
92a notice placed by the copyright holder saying it may be distributed
93under the terms of this General Public License.  The "Program", below,
94refers to any such program or work, and a "work based on the Program"
95means either the Program or any derivative work under copyright law:
96that is to say, a work containing the Program or a portion of it,
97either verbatim or with modifications and/or translated into another
98language.  (Hereinafter, translation is included without limitation in
99the term "modification".)  Each licensee is addressed as "you".
100<p>
101Activities other than copying, distribution and modification are not
102covered by this License; they are outside its scope.  The act of
103running the Program is not restricted, and the output from the Program
104is covered only if its contents constitute a work based on the
105Program (independent of having been made by running the Program).
106Whether that is true depends on what the Program does.
107<p>
108  1. You may copy and distribute verbatim copies of the Program's
109source code as you receive it, in any medium, provided that you
110conspicuously and appropriately publish on each copy an appropriate
111copyright notice and disclaimer of warranty; keep intact all the
112notices that refer to this License and to the absence of any warranty;
113and give any other recipients of the Program a copy of this License
114along with the Program.
115<p>
116You may charge a fee for the physical act of transferring a copy, and
117you may at your option offer warranty protection in exchange for a fee.
118<p>
119  2. You may modify your copy or copies of the Program or any portion
120of it, thus forming a work based on the Program, and copy and
121distribute such modifications or work under the terms of Section 1
122above, provided that you also meet all of these conditions:
123<p>
124<ol type="a">
125    a) You must cause the modified files to carry prominent notices
126    stating that you changed the files and the date of any change.
127<p>
128    b) You must cause any work that you distribute or publish, that in
129    whole or in part contains or is derived from the Program or any
130    part thereof, to be licensed as a whole at no charge to all third
131    parties under the terms of this License.
132<p>
133    c) If the modified program normally reads commands interactively
134    when run, you must cause it, when started running for such
135    interactive use in the most ordinary way, to print or display an
136    announcement including an appropriate copyright notice and a
137    notice that there is no warranty (or else, saying that you provide
138    a warranty) and that users may redistribute the program under
139    these conditions, and telling the user how to view a copy of this
140    License.  (Exception: if the Program itself is interactive but
141    does not normally print such an announcement, your work based on
142    the Program is not required to print an announcement.)
143</ol>
144<p>
145These requirements apply to the modified work as a whole.  If
146identifiable sections of that work are not derived from the Program,
147and can be reasonably considered independent and separate works in
148themselves, then this License, and its terms, do not apply to those
149sections when you distribute them as separate works.  But when you
150distribute the same sections as part of a whole which is a work based
151on the Program, the distribution of the whole must be on the terms of
152this License, whose permissions for other licensees extend to the
153entire whole, and thus to each and every part regardless of who wrote it.
154<p>
155Thus, it is not the intent of this section to claim rights or contest
156your rights to work written entirely by you; rather, the intent is to
157exercise the right to control the distribution of derivative or
158collective works based on the Program.
159<p>
160In addition, mere aggregation of another work not based on the Program
161with the Program (or with a work based on the Program) on a volume of
162a storage or distribution medium does not bring the other work under
163the scope of this License.
164<p>
165  3. You may copy and distribute the Program (or a work based on it,
166under Section 2) in object code or executable form under the terms of
167Sections 1 and 2 above provided that you also do one of the following:
168<p>
169<ol type="a">
170    a) Accompany it with the complete corresponding machine-readable
171    source code, which must be distributed under the terms of Sections
172    1 and 2 above on a medium customarily used for software interchange; or,
173<p>
174    b) Accompany it with a written offer, valid for at least three
175    years, to give any third party, for a charge no more than your
176    cost of physically performing source distribution, a complete
177    machine-readable copy of the corresponding source code, to be
178    distributed under the terms of Sections 1 and 2 above on a medium
179    customarily used for software interchange; or,
180<p>
181    c) Accompany it with the information you received as to the offer
182    to distribute corresponding source code.  (This alternative is
183    allowed only for noncommercial distribution and only if you
184    received the program in object code or executable form with such
185    an offer, in accord with Subsection b above.)
186</ol>
187<p>
188The source code for a work means the preferred form of the work for
189making modifications to it.  For an executable work, complete source
190code means all the source code for all modules it contains, plus any
191associated interface definition files, plus the scripts used to
192control compilation and installation of the executable.  However, as a
193special exception, the source code distributed need not include
194anything that is normally distributed (in either source or binary
195form) with the major components (compiler, kernel, and so on) of the
196operating system on which the executable runs, unless that component
197itself accompanies the executable.
198<p>
199If distribution of executable or object code is made by offering
200access to copy from a designated place, then offering equivalent
201access to copy the source code from the same place counts as
202distribution of the source code, even though third parties are not
203compelled to copy the source along with the object code.
204<p>
205  4. You may not copy, modify, sublicense, or distribute the Program
206except as expressly provided under this License.  Any attempt
207otherwise to copy, modify, sublicense or distribute the Program is
208void, and will automatically terminate your rights under this License.
209However, parties who have received copies, or rights, from you under
210this License will not have their licenses terminated so long as such
211parties remain in full compliance.
212<p>
213  5. You are not required to accept this License, since you have not
214signed it.  However, nothing else grants you permission to modify or
215distribute the Program or its derivative works.  These actions are
216prohibited by law if you do not accept this License.  Therefore, by
217modifying or distributing the Program (or any work based on the
218Program), you indicate your acceptance of this License to do so, and
219all its terms and conditions for copying, distributing or modifying
220the Program or works based on it.
221<p>
222  6. Each time you redistribute the Program (or any work based on the
223Program), the recipient automatically receives a license from the
224original licensor to copy, distribute or modify the Program subject to
225these terms and conditions.  You may not impose any further
226restrictions on the recipients' exercise of the rights granted herein.
227You are not responsible for enforcing compliance by third parties to
228this License.
229<p>
230  7. If, as a consequence of a court judgment or allegation of patent
231infringement or for any other reason (not limited to patent issues),
232conditions are imposed on you (whether by court order, agreement or
233otherwise) that contradict the conditions of this License, they do not
234excuse you from the conditions of this License.  If you cannot
235distribute so as to satisfy simultaneously your obligations under this
236License and any other pertinent obligations, then as a consequence you
237may not distribute the Program at all.  For example, if a patent
238license would not permit royalty-free redistribution of the Program by
239all those who receive copies directly or indirectly through you, then
240the only way you could satisfy both it and this License would be to
241refrain entirely from distribution of the Program.
242<p>
243If any portion of this section is held invalid or unenforceable under
244any particular circumstance, the balance of the section is intended to
245apply and the section as a whole is intended to apply in other
246circumstances.
247<p>
248It is not the purpose of this section to induce you to infringe any
249patents or other property right claims or to contest validity of any
250such claims; this section has the sole purpose of protecting the
251integrity of the free software distribution system, which is
252implemented by public license practices.  Many people have made
253generous contributions to the wide range of software distributed
254through that system in reliance on consistent application of that
255system; it is up to the author/donor to decide if he or she is willing
256to distribute software through any other system and a licensee cannot
257impose that choice.
258<p>
259This section is intended to make thoroughly clear what is believed to
260be a consequence of the rest of this License.
261<p>
262  8. If the distribution and/or use of the Program is restricted in
263certain countries either by patents or by copyrighted interfaces, the
264original copyright holder who places the Program under this License
265may add an explicit geographical distribution limitation excluding
266those countries, so that distribution is permitted only in or among
267countries not thus excluded.  In such case, this License incorporates
268the limitation as if written in the body of this License.
269<p>
270  9. The Free Software Foundation may publish revised and/or new versions
271of the General Public License from time to time.  Such new versions will
272be similar in spirit to the present version, but may differ in detail to
273address new problems or concerns.
274<p>
275Each version is given a distinguishing version number.  If the Program
276specifies a version number of this License which applies to it and "any
277later version", you have the option of following the terms and conditions
278either of that version or of any later version published by the Free
279Software Foundation.  If the Program does not specify a version number of
280this License, you may choose any version ever published by the Free Software
281Foundation.
282<p>
283  10. If you wish to incorporate parts of the Program into other free
284programs whose distribution conditions are different, write to the author
285to ask for permission.  For software which is copyrighted by the Free
286Software Foundation, write to the Free Software Foundation; we sometimes
287make exceptions for this.  Our decision will be guided by the two goals
288of preserving the free status of all derivatives of our free software and
289of promoting the sharing and reuse of software generally.
290<p>
291<h3>
292<center>
293			    NO WARRANTY
294</center>
295</h3>
296<p>
297  11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
298FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
299OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
300PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
301OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
302MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
303TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
304PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
305REPAIR OR CORRECTION.
306<p>
307  12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
308WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
309REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
310INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
311OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
312TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
313YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
314PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
315POSSIBILITY OF SUCH DAMAGES.
316<p>
317		     END OF TERMS AND CONDITIONS
318<p>
319	    How to Apply These Terms to Your New Programs
320<p>
321  If you develop a new program, and you want it to be of the greatest
322possible use to the public, the best way to achieve this is to make it
323free software which everyone can redistribute and change under these terms.
324<p>
325  To do so, attach the following notices to the program.  It is safest
326to attach them to the start of each source file to most effectively
327convey the exclusion of warranty; and each file should have at least
328the "copyright" line and a pointer to where the full notice is found.
329<p>
330<samp>
331<ol>
332    &lt;one line to give the program's name and a brief idea of what it does.&gt;
333    <br>
334    Copyright (C) 19yy  &lt;name of author&gt;
335<p>
336    This program is free software; you can redistribute it and/or modify
337    it under the terms of the GNU General Public License as published by
338    the Free Software Foundation; either version 2 of the License, or
339    (at your option) any later version.
340<p>
341    This program is distributed in the hope that it will be useful,
342    but WITHOUT ANY WARRANTY; without even the implied warranty of
343    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
344    GNU General Public License for more details.
345<p>
346    You should have received a copy of the GNU General Public License
347    along with this program; if not, write to the Free Software
348    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
349<p>
350</ol>
351</samp>
352
353Also add information on how to contact you by electronic and paper mail.
354<p>
355If the program is interactive, make it output a short notice like this
356when it starts in an interactive mode:
357<p>
358<samp>
359<ol>
360    Gnomovision version 69, Copyright (C) 19yy name of author
361<br>
362    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
363<br>
364    This is free software, and you are welcome to redistribute it
365<br>
366    under certain conditions; type `show c' for details.
367</ol>
368</samp>
369<p>
370The hypothetical commands `show w' and `show c' should show the appropriate
371parts of the General Public License.  Of course, the commands you use may
372be called something other than `show w' and `show c'; they could even be
373mouse-clicks or menu items--whatever suits your program.
374<p>
375You should also get your employer (if you work as a programmer) or your
376school, if any, to sign a "copyright disclaimer" for the program, if
377necessary.  Here is a sample; alter the names:
378<p>
379<samp>
380<ol>
381  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
382  <br>
383  `Gnomovision' (which makes passes at compilers) written by James Hacker.
384<p>
385  &lt;signature of Ty Coon&gt;, 1 April 1989
386  <br>
387  Ty Coon, President of Vice
388</ol>
389</samp>
390<p>
391This General Public License does not permit incorporating your program into
392proprietary programs.  If your program is a subroutine library, you may
393consider it more useful to permit linking proprietary applications with the
394library.  If this is what you want to do, use the GNU Library General
395Public License instead of this License.
396<p>
397
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