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      4 <TITLE>GNU General Public License</TITLE>
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      7 <H1>GNU General Public License</H1>
      8 <H2>Table of Contents</H2>
      9 <UL>
     10 
     11   <LI><A NAME="TOC1" HREF="#SEC1">GNU GENERAL PUBLIC LICENSE</A>
     12 <UL>
     13 <LI><A NAME="TOC2" HREF="#SEC2">Preamble</A>
     14 <LI><A NAME="TOC3" HREF="#SEC3">TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION</A>
     15 
     16 </UL>
     17 </UL>
     18 
     19 <P>
     20 
     21 <HR>
     22 
     23 <P>
     24 
     25 
     26 
     27 <H2><A NAME="SEC1" HREF="#TOC1">GNU GENERAL PUBLIC LICENSE</A></H2>
     28 <P>
     29 Version 2, June 1991
     30 
     31 </P>
     32 
     33 <PRE>
     34 Copyright (C) 1989, 1991 Free Software Foundation, Inc.
     35 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA
     36 
     37 Everyone is permitted to copy and distribute verbatim copies
     38 of this license document, but changing it is not allowed.
     39 </PRE>
     40 
     41 
     42 
     43 <H2><A NAME="SEC2" HREF="#TOC2">Preamble</A></H2>
     44 
     45 <P>
     46   The licenses for most software are designed to take away your
     47 freedom to share and change it.  By contrast, the GNU General Public
     48 License is intended to guarantee your freedom to share and change free
     49 software--to make sure the software is free for all its users.  This
     50 General Public License applies to most of the Free Software
     51 Foundation's software and to any other program whose authors commit to
     52 using it.  (Some other Free Software Foundation software is covered by
     53 the GNU Library General Public License instead.)  You can apply it to
     54 your programs, too.
     55 
     56 </P>
     57 <P>
     58   When we speak of free software, we are referring to freedom, not
     59 price.  Our General Public Licenses are designed to make sure that you
     60 have the freedom to distribute copies of free software (and charge for
     61 this service if you wish), that you receive source code or can get it
     62 if you want it, that you can change the software or use pieces of it
     63 in new free programs; and that you know you can do these things.
     64 
     65 </P>
     66 <P>
     67   To protect your rights, we need to make restrictions that forbid
     68 anyone to deny you these rights or to ask you to surrender the rights.
     69 These restrictions translate to certain responsibilities for you if you
     70 distribute copies of the software, or if you modify it.
     71 
     72 </P>
     73 <P>
     74   For example, if you distribute copies of such a program, whether
     75 gratis or for a fee, you must give the recipients all the rights that
     76 you have.  You must make sure that they, too, receive or can get the
     77 source code.  And you must show them these terms so they know their
     78 rights.
     79 
     80 </P>
     81 <P>
     82   We protect your rights with two steps: (1) copyright the software, and
     83 (2) offer you this license which gives you legal permission to copy,
     84 distribute and/or modify the software.
     85 
     86 </P>
     87 <P>
     88   Also, for each author's protection and ours, we want to make certain
     89 that everyone understands that there is no warranty for this free
     90 software.  If the software is modified by someone else and passed on, we
     91 want its recipients to know that what they have is not the original, so
     92 that any problems introduced by others will not reflect on the original
     93 authors' reputations.
     94 
     95 </P>
     96 <P>
     97   Finally, any free program is threatened constantly by software
     98 patents.  We wish to avoid the danger that redistributors of a free
     99 program will individually obtain patent licenses, in effect making the
    100 program proprietary.  To prevent this, we have made it clear that any
    101 patent must be licensed for everyone's free use or not licensed at all.
    102 
    103 </P>
    104 <P>
    105   The precise terms and conditions for copying, distribution and
    106 modification follow.
    107 
    108 </P>
    109 
    110 
    111 <H2><A NAME="SEC3" HREF="#TOC3">TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION</A></H2>
    112 
    113 
    114 <P>
    115 
    116 <STRONG>0.</STRONG>
    117  This License applies to any program or other work which contains
    118 a notice placed by the copyright holder saying it may be distributed
    119 under the terms of this General Public License.  The "Program", below,
    120 refers to any such program or work, and a "work based on the Program"
    121 means either the Program or any derivative work under copyright law:
    122 that is to say, a work containing the Program or a portion of it,
    123 either verbatim or with modifications and/or translated into another
    124 language.  (Hereinafter, translation is included without limitation in
    125 the term "modification".)  Each licensee is addressed as "you".
    126 <P>
    127 
    128 Activities other than copying, distribution and modification are not
    129 covered by this License; they are outside its scope.  The act of
    130 running the Program is not restricted, and the output from the Program
    131 is covered only if its contents constitute a work based on the
    132 Program (independent of having been made by running the Program).
    133 Whether that is true depends on what the Program does.
    134 
    135 <P>
    136 
    137 <STRONG>1.</STRONG>
    138  You may copy and distribute verbatim copies of the Program's
    139 source code as you receive it, in any medium, provided that you
    140 conspicuously and appropriately publish on each copy an appropriate
    141 copyright notice and disclaimer of warranty; keep intact all the
    142 notices that refer to this License and to the absence of any warranty;
    143 and give any other recipients of the Program a copy of this License
    144 along with the Program.
    145 <P>
    146 
    147 You may charge a fee for the physical act of transferring a copy, and
    148 you may at your option offer warranty protection in exchange for a fee.
    149 <P>
    150 
    151 <STRONG>2.</STRONG>
    152  You may modify your copy or copies of the Program or any portion
    153 of it, thus forming a work based on the Program, and copy and
    154 distribute such modifications or work under the terms of Section 1
    155 above, provided that you also meet all of these conditions:
    156 <P>
    157 
    158 <UL>
    159 
    160 <LI><STRONG>a)</STRONG>
    161      You must cause the modified files to carry prominent notices
    162      stating that you changed the files and the date of any change.
    163 
    164 <P>
    165 <LI><STRONG>b)</STRONG>
    166      You must cause any work that you distribute or publish, that in
    167      whole or in part contains or is derived from the Program or any
    168      part thereof, to be licensed as a whole at no charge to all third
    169      parties under the terms of this License.
    170 
    171 <P>
    172 <LI><STRONG>c)</STRONG>
    173      If the modified program normally reads commands interactively
    174      when run, you must cause it, when started running for such
    175      interactive use in the most ordinary way, to print or display an
    176      announcement including an appropriate copyright notice and a
    177      notice that there is no warranty (or else, saying that you provide
    178      a warranty) and that users may redistribute the program under
    179      these conditions, and telling the user how to view a copy of this
    180      License.  (Exception: if the Program itself is interactive but
    181      does not normally print such an announcement, your work based on
    182      the Program is not required to print an announcement.)
    183 </UL>
    184 
    185 These requirements apply to the modified work as a whole.  If
    186 identifiable sections of that work are not derived from the Program,
    187 and can be reasonably considered independent and separate works in
    188 themselves, then this License, and its terms, do not apply to those
    189 sections when you distribute them as separate works.  But when you
    190 distribute the same sections as part of a whole which is a work based
    191 on the Program, the distribution of the whole must be on the terms of
    192 this License, whose permissions for other licensees extend to the
    193 entire whole, and thus to each and every part regardless of who wrote it.
    194 <P>
    195 
    196 Thus, it is not the intent of this section to claim rights or contest
    197 your rights to work written entirely by you; rather, the intent is to
    198 exercise the right to control the distribution of derivative or
    199 collective works based on the Program.
    200 <P>
    201 
    202 In addition, mere aggregation of another work not based on the Program
    203 with the Program (or with a work based on the Program) on a volume of
    204 a storage or distribution medium does not bring the other work under
    205 the scope of this License.
    206 
    207 <P>
    208 
    209 <STRONG>3.</STRONG>
    210  You may copy and distribute the Program (or a work based on it,
    211 under Section 2) in object code or executable form under the terms of
    212 Sections 1 and 2 above provided that you also do one of the following:
    213 
    214 
    215 <!-- we use this doubled UL to get the sub-sections indented, -->
    216 <!-- while making the bullets as unobvious as possible. -->
    217 <UL>
    218 
    219 <LI><STRONG>a)</STRONG>
    220      Accompany it with the complete corresponding machine-readable
    221      source code, which must be distributed under the terms of Sections
    222      1 and 2 above on a medium customarily used for software interchange; or,
    223 
    224 <P>
    225 <LI><STRONG>b)</STRONG>
    226      Accompany it with a written offer, valid for at least three
    227      years, to give any third party, for a charge no more than your
    228      cost of physically performing source distribution, a complete
    229      machine-readable copy of the corresponding source code, to be
    230      distributed under the terms of Sections 1 and 2 above on a medium
    231      customarily used for software interchange; or,
    232 
    233 <P>
    234 <LI><STRONG>c)</STRONG>
    235      Accompany it with the information you received as to the offer
    236      to distribute corresponding source code.  (This alternative is
    237      allowed only for noncommercial distribution and only if you
    238      received the program in object code or executable form with such
    239      an offer, in accord with Subsection b above.)
    240 </UL>
    241 
    242 The source code for a work means the preferred form of the work for
    243 making modifications to it.  For an executable work, complete source
    244 code means all the source code for all modules it contains, plus any
    245 associated interface definition files, plus the scripts used to
    246 control compilation and installation of the executable.  However, as a
    247 special exception, the source code distributed need not include
    248 anything that is normally distributed (in either source or binary
    249 form) with the major components (compiler, kernel, and so on) of the
    250 operating system on which the executable runs, unless that component
    251 itself accompanies the executable.
    252 <P>
    253 
    254 If distribution of executable or object code is made by offering
    255 access to copy from a designated place, then offering equivalent
    256 access to copy the source code from the same place counts as
    257 distribution of the source code, even though third parties are not
    258 compelled to copy the source along with the object code.
    259 <P>
    260 
    261 <STRONG>4.</STRONG>
    262  You may not copy, modify, sublicense, or distribute the Program
    263 except as expressly provided under this License.  Any attempt
    264 otherwise to copy, modify, sublicense or distribute the Program is
    265 void, and will automatically terminate your rights under this License.
    266 However, parties who have received copies, or rights, from you under
    267 this License will not have their licenses terminated so long as such
    268 parties remain in full compliance.
    269 
    270 <P>
    271 
    272 <STRONG>5.</STRONG>
    273  You are not required to accept this License, since you have not
    274 signed it.  However, nothing else grants you permission to modify or
    275 distribute the Program or its derivative works.  These actions are
    276 prohibited by law if you do not accept this License.  Therefore, by
    277 modifying or distributing the Program (or any work based on the
    278 Program), you indicate your acceptance of this License to do so, and
    279 all its terms and conditions for copying, distributing or modifying
    280 the Program or works based on it.
    281 
    282 <P>
    283 
    284 <STRONG>6.</STRONG>
    285  Each time you redistribute the Program (or any work based on the
    286 Program), the recipient automatically receives a license from the
    287 original licensor to copy, distribute or modify the Program subject to
    288 these terms and conditions.  You may not impose any further
    289 restrictions on the recipients' exercise of the rights granted herein.
    290 You are not responsible for enforcing compliance by third parties to
    291 this License.
    292 
    293 <P>
    294 
    295 <STRONG>7.</STRONG>
    296  If, as a consequence of a court judgment or allegation of patent
    297 infringement or for any other reason (not limited to patent issues),
    298 conditions are imposed on you (whether by court order, agreement or
    299 otherwise) that contradict the conditions of this License, they do not
    300 excuse you from the conditions of this License.  If you cannot
    301 distribute so as to satisfy simultaneously your obligations under this
    302 License and any other pertinent obligations, then as a consequence you
    303 may not distribute the Program at all.  For example, if a patent
    304 license would not permit royalty-free redistribution of the Program by
    305 all those who receive copies directly or indirectly through you, then
    306 the only way you could satisfy both it and this License would be to
    307 refrain entirely from distribution of the Program.
    308 <P>
    309 
    310 If any portion of this section is held invalid or unenforceable under
    311 any particular circumstance, the balance of the section is intended to
    312 apply and the section as a whole is intended to apply in other
    313 circumstances.
    314 <P>
    315 
    316 It is not the purpose of this section to induce you to infringe any
    317 patents or other property right claims or to contest validity of any
    318 such claims; this section has the sole purpose of protecting the
    319 integrity of the free software distribution system, which is
    320 implemented by public license practices.  Many people have made
    321 generous contributions to the wide range of software distributed
    322 through that system in reliance on consistent application of that
    323 system; it is up to the author/donor to decide if he or she is willing
    324 to distribute software through any other system and a licensee cannot
    325 impose that choice.
    326 <P>
    327 
    328 This section is intended to make thoroughly clear what is believed to
    329 be a consequence of the rest of this License.
    330 
    331 <P>
    332 
    333 <STRONG>8.</STRONG>
    334  If the distribution and/or use of the Program is restricted in
    335 certain countries either by patents or by copyrighted interfaces, the
    336 original copyright holder who places the Program under this License
    337 may add an explicit geographical distribution limitation excluding
    338 those countries, so that distribution is permitted only in or among
    339 countries not thus excluded.  In such case, this License incorporates
    340 the limitation as if written in the body of this License.
    341 
    342 <P>
    343 
    344 <STRONG>9.</STRONG>
    345  The Free Software Foundation may publish revised and/or new versions
    346 of the General Public License from time to time.  Such new versions will
    347 be similar in spirit to the present version, but may differ in detail to
    348 address new problems or concerns.
    349 <P>
    350 
    351 Each version is given a distinguishing version number.  If the Program
    352 specifies a version number of this License which applies to it and "any
    353 later version", you have the option of following the terms and conditions
    354 either of that version or of any later version published by the Free
    355 Software Foundation.  If the Program does not specify a version number of
    356 this License, you may choose any version ever published by the Free Software
    357 Foundation.
    358 
    359 <P>
    360 
    361 
    362 <STRONG>10.</STRONG>
    363  If you wish to incorporate parts of the Program into other free
    364 programs whose distribution conditions are different, write to the author
    365 to ask for permission.  For software which is copyrighted by the Free
    366 Software Foundation, write to the Free Software Foundation; we sometimes
    367 make exceptions for this.  Our decision will be guided by the two goals
    368 of preserving the free status of all derivatives of our free software and
    369 of promoting the sharing and reuse of software generally.
    370 
    371 
    372 
    373 <P><STRONG>NO WARRANTY</STRONG></P>
    374 
    375 <P>
    376 
    377 <STRONG>11.</STRONG>
    378  BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
    379 FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN
    380 OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
    381 PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED
    382 OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
    383 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS
    384 TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE
    385 PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
    386 REPAIR OR CORRECTION.
    387 
    388 <P>
    389 
    390 <STRONG>12.</STRONG>
    391  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
    392 WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR
    393 REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
    394 INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING
    395 OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED
    396 TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY
    397 YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER
    398 PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
    399 POSSIBILITY OF SUCH DAMAGES.
    400 
    401 <P>
    402 
    403 
    404 <H2>END OF TERMS AND CONDITIONS</H2>
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