1 The GNU General Public License (GPL)

     2 

     3 Version 2, June 1991

     4 

     5 Copyright (C) 1989, 1991 Free Software Foundation, Inc.

     6 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

     7 

     8 Everyone is permitted to copy and distribute verbatim copies of this license

     9 document, but changing it is not allowed.

    10 

    11 Preamble

    12 

    13 The licenses for most software are designed to take away your freedom to share

    14 and change it.  By contrast, the GNU General Public License is intended to

    15 guarantee your freedom to share and change free software--to make sure the

    16 software is free for all its users.  This General Public License applies to

    17 most of the Free Software Foundation's software and to any other program whose

    18 authors commit to using it.  (Some other Free Software Foundation software is

    19 covered by the GNU Library General Public License instead.) You can apply it to

    20 your programs, too.

    21 

    22 When we speak of free software, we are referring to freedom, not price.  Our

    23 General Public Licenses are designed to make sure that you have the freedom to

    24 distribute copies of free software (and charge for this service if you wish),

    25 that you receive source code or can get it if you want it, that you can change

    26 the software or use pieces of it in new free programs; and that you know you

    27 can do these things.

    28 

    29 To protect your rights, we need to make restrictions that forbid anyone to deny

    30 you these rights or to ask you to surrender the rights.  These restrictions

    31 translate to certain responsibilities for you if you distribute copies of the

    32 software, or if you modify it.

    33 

    34 For example, if you distribute copies of such a program, whether gratis or for

    35 a fee, you must give the recipients all the rights that you have.  You must

    36 make sure that they, too, receive or can get the source code.  And you must

    37 show them these terms so they know their rights.

    38 

    39 We protect your rights with two steps: (1) copyright the software, and (2)

    40 offer you this license which gives you legal permission to copy, distribute

    41 and/or modify the software.

    42 

    43 Also, for each author's protection and ours, we want to make certain that

    44 everyone understands that there is no warranty for this free software.  If the

    45 software is modified by someone else and passed on, we want its recipients to

    46 know that what they have is not the original, so that any problems introduced

    47 by others will not reflect on the original authors' reputations.

    48 

    49 Finally, any free program is threatened constantly by software patents.  We

    50 wish to avoid the danger that redistributors of a free program will

    51 individually obtain patent licenses, in effect making the program proprietary.

    52 To prevent this, we have made it clear that any patent must be licensed for

    53 everyone's free use or not licensed at all.

    54 

    55 The precise terms and conditions for copying, distribution and modification

    56 follow.

    57 

    58 TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION

    59 

    60 0. This License applies to any program or other work which contains a notice

    61 placed by the copyright holder saying it may be distributed under the terms of

    62 this General Public License.  The "Program", below, refers to any such program

    63 or work, and a "work based on the Program" means either the Program or any

    64 derivative work under copyright law: that is to say, a work containing the

    65 Program or a portion of it, either verbatim or with modifications and/or

    66 translated into another language.  (Hereinafter, translation is included

    67 without limitation in the term "modification".) Each licensee is addressed as

    68 "you".

    69 

    70 Activities other than copying, distribution and modification are not covered by

    71 this License; they are outside its scope.  The act of running the Program is

    72 not restricted, and the output from the Program is covered only if its contents

    73 constitute a work based on the Program (independent of having been made by

    74 running the Program).  Whether that is true depends on what the Program does.

    75 

    76 1. You may copy and distribute verbatim copies of the Program's source code as

    77 you receive it, in any medium, provided that you conspicuously and

    78 appropriately publish on each copy an appropriate copyright notice and

    79 disclaimer of warranty; keep intact all the notices that refer to this License

    80 and to the absence of any warranty; and give any other recipients of the

    81 Program a copy of this License along with the Program.

    82 

    83 You may charge a fee for the physical act of transferring a copy, and you may

    84 at your option offer warranty protection in exchange for a fee.

    85 

    86 2. You may modify your copy or copies of the Program or any portion of it, thus

    87 forming a work based on the Program, and copy and distribute such modifications

    88 or work under the terms of Section 1 above, provided that you also meet all of

    89 these conditions:

    90 

    91     a) You must cause the modified files to carry prominent notices stating

    92     that you changed the files and the date of any change.

    93 

    94     b) You must cause any work that you distribute or publish, that in whole or

    95     in part contains or is derived from the Program or any part thereof, to be

    96     licensed as a whole at no charge to all third parties under the terms of

    97     this License.

    98 

    99     c) If the modified program normally reads commands interactively when run,

   100     you must cause it, when started running for such interactive use in the

   101     most ordinary way, to print or display an announcement including an

   102     appropriate copyright notice and a notice that there is no warranty (or

   103     else, saying that you provide a warranty) and that users may redistribute

   104     the program under these conditions, and telling the user how to view a copy

   105     of this License.  (Exception: if the Program itself is interactive but does

   106     not normally print such an announcement, your work based on the Program is

   107     not required to print an announcement.)

   108 

   109 These requirements apply to the modified work as a whole.  If identifiable

   110 sections of that work are not derived from the Program, and can be reasonably

   111 considered independent and separate works in themselves, then this License, and

   112 its terms, do not apply to those sections when you distribute them as separate

   113 works.  But when you distribute the same sections as part of a whole which is a

   114 work based on the Program, the distribution of the whole must be on the terms

   115 of this License, whose permissions for other licensees extend to the entire

   116 whole, and thus to each and every part regardless of who wrote it.

   117 

   118 Thus, it is not the intent of this section to claim rights or contest your

   119 rights to work written entirely by you; rather, the intent is to exercise the

   120 right to control the distribution of derivative or collective works based on

   121 the Program.

   122 

   123 In addition, mere aggregation of another work not based on the Program with the

   124 Program (or with a work based on the Program) on a volume of a storage or

   125 distribution medium does not bring the other work under the scope of this

   126 License.

   127 

   128 3. You may copy and distribute the Program (or a work based on it, under

   129 Section 2) in object code or executable form under the terms of Sections 1 and

   130 2 above provided that you also do one of the following:

   131 

   132     a) Accompany it with the complete corresponding machine-readable source

   133     code, which must be distributed under the terms of Sections 1 and 2 above

   134     on a medium customarily used for software interchange; or,

   135 

   136     b) Accompany it with a written offer, valid for at least three years, to

   137     give any third party, for a charge no more than your cost of physically

   138     performing source distribution, a complete machine-readable copy of the

   139     corresponding source code, to be distributed under the terms of Sections 1

   140     and 2 above on a medium customarily used for software interchange; or,

   141 

   142     c) Accompany it with the information you received as to the offer to

   143     distribute corresponding source code.  (This alternative is allowed only

   144     for noncommercial distribution and only if you received the program in

   145     object code or executable form with such an offer, in accord with

   146     Subsection b above.)

   147 

   148 The source code for a work means the preferred form of the work for making

   149 modifications to it.  For an executable work, complete source code means all

   150 the source code for all modules it contains, plus any associated interface

   151 definition files, plus the scripts used to control compilation and installation

   152 of the executable.  However, as a special exception, the source code

   153 distributed need not include anything that is normally distributed (in either

   154 source or binary form) with the major components (compiler, kernel, and so on)

   155 of the operating system on which the executable runs, unless that component

   156 itself accompanies the executable.

   157 

   158 If distribution of executable or object code is made by offering access to copy

   159 from a designated place, then offering equivalent access to copy the source

   160 code from the same place counts as distribution of the source code, even though

   161 third parties are not compelled to copy the source along with the object code.

   162 

   163 4. You may not copy, modify, sublicense, or distribute the Program except as

   164 expressly provided under this License.  Any attempt otherwise to copy, modify,

   165 sublicense or distribute the Program is void, and will automatically terminate

   166 your rights under this License.  However, parties who have received copies, or

   167 rights, from you under this License will not have their licenses terminated so

   168 long as such parties remain in full compliance.

   169 

   170 5. You are not required to accept this License, since you have not signed it.

   171 However, nothing else grants you permission to modify or distribute the Program

   172 or its derivative works.  These actions are prohibited by law if you do not

   173 accept this License.  Therefore, by modifying or distributing the Program (or

   174 any work based on the Program), you indicate your acceptance of this License to

   175 do so, and all its terms and conditions for copying, distributing or modifying

   176 the Program or works based on it.

   177 

   178 6. Each time you redistribute the Program (or any work based on the Program),

   179 the recipient automatically receives a license from the original licensor to

   180 copy, distribute or modify the Program subject to these terms and conditions.

   181 You may not impose any further restrictions on the recipients' exercise of the

   182 rights granted herein.  You are not responsible for enforcing compliance by

   183 third parties to this License.

   184 

   185 7. If, as a consequence of a court judgment or allegation of patent

   186 infringement or for any other reason (not limited to patent issues), conditions

   187 are imposed on you (whether by court order, agreement or otherwise) that

   188 contradict the conditions of this License, they do not excuse you from the

   189 conditions of this License.  If you cannot distribute so as to satisfy

   190 simultaneously your obligations under this License and any other pertinent

   191 obligations, then as a consequence you may not distribute the Program at all.

   192 For example, if a patent license would not permit royalty-free redistribution

   193 of the Program by all those who receive copies directly or indirectly through

   194 you, then the only way you could satisfy both it and this License would be to

   195 refrain entirely from distribution of the Program.

   196 

   197 If any portion of this section is held invalid or unenforceable under any

   198 particular circumstance, the balance of the section is intended to apply and

   199 the section as a whole is intended to apply in other circumstances.

   200 

   201 It is not the purpose of this section to induce you to infringe any patents or

   202 other property right claims or to contest validity of any such claims; this

   203 section has the sole purpose of protecting the integrity of the free software

   204 distribution system, which is implemented by public license practices.  Many

   205 people have made generous contributions to the wide range of software

   206 distributed through that system in reliance on consistent application of that

   207 system; it is up to the author/donor to decide if he or she is willing to

   208 distribute software through any other system and a licensee cannot impose that

   209 choice.

   210 

   211 This section is intended to make thoroughly clear what is believed to be a

   212 consequence of the rest of this License.

   213 

   214 8. If the distribution and/or use of the Program is restricted in certain

   215 countries either by patents or by copyrighted interfaces, the original

   216 copyright holder who places the Program under this License may add an explicit

   217 geographical distribution limitation excluding those countries, so that

   218 distribution is permitted only in or among countries not thus excluded.  In

   219 such case, this License incorporates the limitation as if written in the body

   220 of this License.

   221 

   222 9. The Free Software Foundation may publish revised and/or new versions of the

   223 General Public License from time to time.  Such new versions will be similar in

   224 spirit to the present version, but may differ in detail to address new problems

   225 or concerns.

   226 

   227 Each version is given a distinguishing version number.  If the Program

   228 specifies a version number of this License which applies to it and "any later

   229 version", you have the option of following the terms and conditions either of

   230 that version or of any later version published by the Free Software Foundation.

   231 If the Program does not specify a version number of this License, you may

   232 choose any version ever published by the Free Software Foundation.

   233 

   234 10. If you wish to incorporate parts of the Program into other free programs

   235 whose distribution conditions are different, write to the author to ask for

   236 permission.  For software which is copyrighted by the Free Software Foundation,

   237 write to the Free Software Foundation; we sometimes make exceptions for this.

   238 Our decision will be guided by the two goals of preserving the free status of

   239 all derivatives of our free software and of promoting the sharing and reuse of

   240 software generally.

   241 

   242 NO WARRANTY

   243 

   244 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR

   245 THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.  EXCEPT WHEN OTHERWISE

   246 STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE

   247 PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED,

   248 INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND

   249 FITNESS FOR A PARTICULAR PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND

   250 PERFORMANCE OF THE PROGRAM IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE,

   251 YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

   252 

   253 12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL

   254 ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE THE

   255 PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY

   256 GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR

   257 INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA

   258 BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A

   259 FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER

   260 OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

   261 

   262 END OF TERMS AND CONDITIONS

   263 

   264 How to Apply These Terms to Your New Programs

   265 

   266 If you develop a new program, and you want it to be of the greatest possible

   267 use to the public, the best way to achieve this is to make it free software

   268 which everyone can redistribute and change under these terms.

   269 

   270 To do so, attach the following notices to the program.  It is safest to attach

   271 them to the start of each source file to most effectively convey the exclusion

   272 of warranty; and each file should have at least the "copyright" line and a

   273 pointer to where the full notice is found.

   274 

   275     One line to give the program's name and a brief idea of what it does.

   276 

   277     Copyright (C) <year> <name of author>

   278 

   279     This program is free software; you can redistribute it and/or modify it

   280     under the terms of the GNU General Public License as published by the Free

   281     Software Foundation; either version 2 of the License, or (at your option)

   282     any later version.

   283 

   284     This program is distributed in the hope that it will be useful, but WITHOUT

   285     ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

   286     FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for

   287     more details.

   288 

   289     You should have received a copy of the GNU General Public License along

   290     with this program; if not, write to the Free Software Foundation, Inc., 59

   291     Temple Place, Suite 330, Boston, MA 02111-1307 USA

   292 

   293 Also add information on how to contact you by electronic and paper mail.

   294 

   295 If the program is interactive, make it output a short notice like this when it

   296 starts in an interactive mode:

   297 

   298     Gnomovision version 69, Copyright (C) year name of author Gnomovision comes

   299     with ABSOLUTELY NO WARRANTY; for details type 'show w'.  This is free

   300     software, and you are welcome to redistribute it under certain conditions;

   301     type 'show c' for details.

   302 

   303 The hypothetical commands 'show w' and 'show c' should show the appropriate

   304 parts of the General Public License.  Of course, the commands you use may be

   305 called something other than 'show w' and 'show c'; they could even be

   306 mouse-clicks or menu items--whatever suits your program.

   307 

   308 You should also get your employer (if you work as a programmer) or your school,

   309 if any, to sign a "copyright disclaimer" for the program, if necessary.  Here

   310 is a sample; alter the names:

   311 

   312     Yoyodyne, Inc., hereby disclaims all copyright interest in the program

   313     'Gnomovision' (which makes passes at compilers) written by James Hacker.

   314 

   315     signature of Ty Coon, 1 April 1989

   316 

   317     Ty Coon, President of Vice

   318 

   319 This General Public License does not permit incorporating your program into

   320 proprietary programs.  If your program is a subroutine library, you may

   321 consider it more useful to permit linking proprietary applications with the

   322 library.  If this is what you want to do, use the GNU Library General Public

   323 License instead of this License.

   324