Perl 5 version 26.3 documentation

perlgpl

SYNOPSIS

  1. You can refer to this document in Pod via "L<perlgpl>"
  2. Or you can see this document by entering "perldoc perlgpl"

DESCRIPTION

Perl is free software; you can redistribute it and/or modify it under the terms of either:

  1. a) the GNU General Public License as published by the Free
  2. Software Foundation; either version 1, or (at your option) any
  3. later version, or
  4. b) the "Artistic License" which comes with this Kit.

This is the "GNU General Public License, version 1". It's here so that modules, programs, etc., that want to declare this as their distribution license can link to it.

For the Perl Artistic License, see perlartistic.

GNU GENERAL PUBLIC LICENSE

  1. GNU GENERAL PUBLIC LICENSE
  2. Version 1, February 1989
  3. Copyright (C) 1989 Free Software Foundation, Inc.
  4. 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  5. Everyone is permitted to copy and distribute verbatim copies
  6. of this license document, but changing it is not allowed.
  7. Preamble
  8. The license agreements of most software companies try to keep users
  9. at the mercy of those companies. By contrast, our General Public
  10. License is intended to guarantee your freedom to share and change free
  11. software--to make sure the software is free for all its users. The
  12. General Public License applies to the Free Software Foundation's
  13. software and to any other program whose authors commit to using it.
  14. You can use it for your programs, too.
  15. When we speak of free software, we are referring to freedom, not
  16. price. Specifically, the General Public License is designed to make
  17. sure that you have the freedom to give away or sell copies of free
  18. software, that you receive source code or can get it if you want it,
  19. that you can change the software or use pieces of it in new free
  20. programs; and that you know you can do these things.
  21. To protect your rights, we need to make restrictions that forbid
  22. anyone to deny you these rights or to ask you to surrender the rights.
  23. These restrictions translate to certain responsibilities for you if you
  24. distribute copies of the software, or if you modify it.
  25. For example, if you distribute copies of a such a program, whether
  26. gratis or for a fee, you must give the recipients all the rights that
  27. you have. You must make sure that they, too, receive or can get the
  28. source code. And you must tell them their rights.
  29. We protect your rights with two steps: (1) copyright the software,
  30. and (2) offer you this license which gives you legal permission to
  31. copy, distribute and/or modify the software.
  32. Also, for each author's protection and ours, we want to make certain
  33. that everyone understands that there is no warranty for this free
  34. software. If the software is modified by someone else and passed on,
  35. we want its recipients to know that what they have is not the original,
  36. so that any problems introduced by others will not reflect on the
  37. original authors' reputations.
  38. The precise terms and conditions for copying, distribution and
  39. modification follow.
  40. GNU GENERAL PUBLIC LICENSE
  41. TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
  42. 0. This License Agreement applies to any program or other work which
  43. contains a notice placed by the copyright holder saying it may be
  44. distributed under the terms of this General Public License. The
  45. "Program", below, refers to any such program or work, and a "work based
  46. on the Program" means either the Program or any work containing the
  47. Program or a portion of it, either verbatim or with modifications.
  48. Each licensee is addressed as "you".
  49. 1. You may copy and distribute verbatim copies of the Program's
  50. source code as you receive it, in any medium, provided that you
  51. conspicuously and appropriately publish on each copy an appropriate
  52. copyright notice and disclaimer of warranty; keep intact all the
  53. notices that refer to this General Public License and to the absence of
  54. any warranty; and give any other recipients of the Program a copy of
  55. this General Public License along with the Program. You may charge a
  56. fee for the physical act of transferring a copy.
  57. 2. You may modify your copy or copies of the Program or any portion
  58. of it, and copy and distribute such modifications under the terms of
  59. Paragraph 1 above, provided that you also do the following:
  60. a) cause the modified files to carry prominent notices stating that
  61. you changed the files and the date of any change; and
  62. b) cause the whole of any work that you distribute or publish, that
  63. in whole or in part contains the Program or any part thereof,
  64. either with or without modifications, to be licensed at no charge
  65. to all third parties under the terms of this General Public License
  66. (except that you may choose to grant warranty protection to some or
  67. all third parties, at your option).
  68. c) If the modified program normally reads commands interactively
  69. when run, you must cause it, when started running for such
  70. interactive use in the simplest and most usual way, to print or
  71. display an announcement including an appropriate copyright notice
  72. and a notice that there is no warranty (or else, saying that you
  73. provide a warranty) and that users may redistribute the program
  74. under these conditions, and telling the user how to view a copy of
  75. this General Public License.
  76. d) You may charge a fee for the physical act of transferring a
  77. copy, and you may at your option offer warranty protection in
  78. exchange for a fee.
  79. Mere aggregation of another independent work with the Program (or its
  80. derivative) on a volume of a storage or distribution medium does not
  81. bring the other work under the scope of these terms.
  82. 3. You may copy and distribute the Program (or a portion or
  83. derivative of it, under Paragraph 2) in object code or executable form
  84. under the terms of Paragraphs 1 and 2 above provided that you also do
  85. one of the following:
  86. a) accompany it with the complete corresponding machine-readable
  87. source code, which must be distributed under the terms of
  88. Paragraphs 1 and 2 above; or,
  89. b) accompany it with a written offer, valid for at least three
  90. years, to give any third party free (except for a nominal charge
  91. for the cost of distribution) a complete machine-readable copy of
  92. the corresponding source code, to be distributed under the terms of
  93. Paragraphs 1 and 2 above; or,
  94. c) accompany it with the information you received as to where the
  95. corresponding source code may be obtained. (This alternative is
  96. allowed only for noncommercial distribution and only if you
  97. received the program in object code or executable form alone.)
  98. Source code for a work means the preferred form of the work for making
  99. modifications to it. For an executable file, complete source code
  100. means all the source code for all modules it contains; but, as a
  101. special exception, it need not include source code for modules which
  102. are standard libraries that accompany the operating system on which the
  103. executable file runs, or for standard header files or definitions files
  104. that accompany that operating system.
  105. 4. You may not copy, modify, sublicense, distribute or transfer the
  106. Program except as expressly provided under this General Public License.
  107. Any attempt otherwise to copy, modify, sublicense, distribute or
  108. transfer the Program is void, and will automatically terminate your
  109. rights to use the Program under this License. However, parties who
  110. have received copies, or rights to use copies, from you under this
  111. General Public License will not have their licenses terminated so long
  112. as such parties remain in full compliance.
  113. 5. By copying, distributing or modifying the Program (or any work
  114. based on the Program) you indicate your acceptance of this license to
  115. do so, and all its terms and conditions.
  116. 6. Each time you redistribute the Program (or any work based on the
  117. Program), the recipient automatically receives a license from the
  118. original licensor to copy, distribute or modify the Program subject to
  119. these terms and conditions. You may not impose any further
  120. restrictions on the recipients' exercise of the rights granted herein.
  121. 7. The Free Software Foundation may publish revised and/or new
  122. versions of the General Public License from time to time. Such new
  123. versions will be similar in spirit to the present version, but may
  124. differ in detail to address new problems or concerns.
  125. Each version is given a distinguishing version number. If the Program
  126. specifies a version number of the license which applies to it and "any
  127. later version", you have the option of following the terms and
  128. conditions either of that version or of any later version published by
  129. the Free Software Foundation. If the Program does not specify a
  130. version number of the license, you may choose any version ever
  131. published by the Free Software Foundation.
  132. 8. If you wish to incorporate parts of the Program into other free
  133. programs whose distribution conditions are different, write to the
  134. author to ask for permission. For software which is copyrighted by the
  135. Free Software Foundation, write to the Free Software Foundation; we
  136. sometimes make exceptions for this. Our decision will be guided by the
  137. two goals of preserving the free status of all derivatives of our free
  138. software and of promoting the sharing and reuse of software generally.
  139. NO WARRANTY
  140. 9. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO
  141. WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW.
  142. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR
  143. OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY OF ANY KIND,
  144. EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  145. WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  146. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS
  147. WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
  148. ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
  149. 10. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
  150. WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY
  151. AND/OR REDISTRIBUTE THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU
  152. FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR
  153. CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE
  154. PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
  155. RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
  156. FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF
  157. SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  158. DAMAGES.
  159. END OF TERMS AND CONDITIONS
  160. Appendix: How to Apply These Terms to Your New Programs
  161. If you develop a new program, and you want it to be of the greatest
  162. possible use to humanity, the best way to achieve this is to make it
  163. free software which everyone can redistribute and change under these
  164. terms.
  165. To do so, attach the following notices to the program. It is safest
  166. to attach them to the start of each source file to most effectively
  167. convey the exclusion of warranty; and each file should have at least
  168. the "copyright" line and a pointer to where the full notice is found.
  169. <one line to give the program's name and a brief idea of what it
  170. does.>
  171. Copyright (C) 19yy <name of author>
  172. This program is free software; you can redistribute it and/or
  173. modify it under the terms of the GNU General Public License as
  174. published by the Free Software Foundation; either version 1, or (at
  175. your option) any later version.
  176. This program is distributed in the hope that it will be useful,
  177. but WITHOUT ANY WARRANTY; without even the implied warranty of
  178. MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  179. GNU General Public License for more details.
  180. You should have received a copy of the GNU General Public License
  181. along with this program; if not, write to the Free Software
  182. Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA
  183. 02110-1301 USA
  184. Also add information on how to contact you by electronic and paper
  185. mail.
  186. If the program is interactive, make it output a short notice like this
  187. when it starts in an interactive mode:
  188. Gnomovision version 69, Copyright (C) 19xx name of author
  189. Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type
  190. 'show w'. This is free software, and you are welcome to
  191. redistribute it under certain conditions; type 'show c' for
  192. details.
  193. The hypothetical commands 'show w' and 'show c' should show the
  194. appropriate parts of the General Public License. Of course, the
  195. commands you use may be called something other than 'show w' and 'show
  196. c'; they could even be mouse-clicks or menu items--whatever suits your
  197. program.
  198. You should also get your employer (if you work as a programmer) or your
  199. school, if any, to sign a "copyright disclaimer" for the program, if
  200. necessary. Here a sample; alter the names:
  201. Yoyodyne, Inc., hereby disclaims all copyright interest in the
  202. program 'Gnomovision' (a program to direct compilers to make passes
  203. at assemblers) written by James Hacker.
  204. <signature of Ty Coon>, 1 April 1989
  205. Ty Coon, President of Vice
  206. That's all there is to it!