序言
大多数软件许可证决意剥夺你的共享和修改软件的自由。对比之下，GNU通用公共许可证力图保证你的共享和修改自由软件的自由。——保证自由软件对所有用户是自由的。GPL适用于大多数自由软件基金会的软件，以及由使用这些软件而承担义务的作者所开发的软件。（自由软件基金会的其他一些软件受GNU库通用许可证的保护）。你也可以将它用到你的程序中。
当我们谈到自由软件（free software）时，我们指的是自由而不是价格。
我们的GNU通用公共许可证决意保证你有发布自由软件的自由（如果你愿意，你可以对此项服务收取一定的费用）；保证你能收到源程序或者在你需要时能得到它；保证你能修改软件或将它的一部分用于新的自由软件；而且还保证你知道你能做这些事情。
为了保护你的权利，我们需要作出规定：禁止任何人不承认你的权利，或者要求你放弃这些权利。如果你修改了自由软件或者发布了软件的副本，这些规定就转化为你的责任。
例如，如果你发布这样一个程序的副本，不管是收费的还是免费的，你必须将你具有的一切权利给予你的接受者；你必须保证他们能收到或得到源程序；并且将这些条款给他们看，使他们知道他们有这样的权利。
我们采取两项措施来保护你的权利。
（1）给软件以版权保护。
（2）给你提供许可证。它给你复制，发布和修改这些软件的法律许可。
同样，为了保护每个作者和我们自己，我们需要清楚地让每个人明白，自由软件没有担保（no warranty）。如果由于其他某个人修改了软件，并继续加以传播。我们需要它的接受者明白：他们所得到的并不是原来的自由软件。由其他人引入的任何问题，不应损害原作者的声誉。
最后，任何自由软件不断受到软件专利的威胁。我们希望避免这样的风险，自由软件的再发布者以个人名义获得专利许可证。事实上，将软件变为私有。为防止这一点，我们必须明确：任何专利必须以允许每个人自由使用为前提，否则就不准许有专利。
下面是有关复制，发布和修改的确切的条款和条件。
GNU通用公共许可证
有关复制，发布和修改的条款和条件
0. 此许可证适用于任何包含版权所有者声明的程序和其他作品，版权所有者在声明中明确说明程序和作品可以在GPL条款的约束下发布。下面提到的“程序”
指的是任何这样的程序或作品。而“基于程序的作品”指的是程序或者任何受版权法约束的衍生作品。也就是说包含程序或程序的一部分的作品。可以是原封不动的，或经过修改的和／或翻译成其他语言的（程序）。在下文中，翻译包含在修改的条款中。每个许可证接受人（licensee）用你来称呼。
许可证条款不适用于复制，发布和修改以外的活动。这些活动超出这些条款的范围。运行程序的活动不受条款的限止。仅当程序的输出构成基于程序作品的内容时，这一条款才适用（如果只运行程序就无关）。是否普遍适用取决于程序具体用来做什么。
1. 只要你在每一副本上明显和恰当地出版版权声明和不 械５１５ 声明，保持此许可证的声明和没有担保的声明完整无损，并和程序一起给每个其他的程序接受者一份许可证的副本，你就可以用任何媒体复制和发布你收到的原始的程序的源代码。
你可以为转让副本的实际行动收取一定费用。你也有权选择提供担保以换取一定的费用。
2. 你可以修改程序的一个或几个副本或程序的任何部分，以此形成基于程序的作品。只要你同时满足下面的所有条件，你就可以按前面第一款的要求复制和发布这一经过修改的程序或作品。
a） 你必须在修改的文件中附有明确的说明：你修改了这一文件及具体的修改日期。
b） 你必须使你发布或出版的作品（它包含程序的全部或一部分，或包含由程序的全部或部分衍生的作品）允许第三方作为整体按许可证条款免费使用。
c） 如果修改的程序在运行时以交互方式读取命令，你必须使它在开始进入常规的交互使用方式时打印或显示声明：包括适当的版权声明和没有担保的声明（或者你提供担保的声明）；用户可以按此许可证条款重新发布程序的说明；并告诉用户如何看到这一许可证的副本。（例外的情况：如果原始程序以交互方式工作，它并不打印这样的声明，你的基于程序的作品也就不用打印声明）。
这些要求适用于修改了的作品的整体。如果能够确定作品的一部分并非程序的衍生产品，可以合理地认为这部分是独立的，是不同的作品。当你将它作为独立作品发布时，它不受此许可证和它的条款的约束。但是当你将这部分作为基于程序的作品的一部分发布时，作为整体它将受到许可证条款约束。准予其他许可证持有人的使用范围扩大到整个产品。也就是每个部分，不管它是谁写的。
因此，本条款的意图不在于索取权利；或剥夺全部由你写成的作品的权利。
而是履行权利来控制基于程序的集体作品或衍生作品的发布。
此外，将与程序无关的作品和该程序或基于程序的作品一起放在存贮体或发布媒体的同一卷上，并不导致将其他作品置于此许可证的约束范围之内。
3. 你可以以目标码或可执行形式复制或发布程序（或符合第2款的基于程序的作品），只要你遵守前面的第1，2款，并同时满足下列3条中的1条。
a）在通常用作软件交换的媒体上，和目标码一起附有机器可读的完整的源码。这些源码的发布应符合上面第1，2款的要求。或者
b）在通常用作软件交换的媒体上，和目标码一起，附有给第三方提供相应的机器可读的源码的书面报价。有效期不少于3年，费用不超过实际完成源程序发布的实际成本。源码的发布应符合上面的第1，2款的要求。或者
c）和目标码一起，附有你收到的发布源码的报价信息。（这一条款只适用于非商业性发布，而且你只收到程序的目标码或可执行代码和按b）款要求提供的报价）。
作品的源码指的是对作品进行修改最优先择取的形式。对可执行的作品讲，完整的源码包括：所有模块的所有源程序，加上有关的接口的定义，加上控制可执行作品的安装和编译的script.作为特殊例外，发布的源码不必包含任何常规发布的供可执行代码在上面运行的操作系统的主要组成部分（如编译程序，内核等）。除非这些组成部分和可执行作品结合在一起。[page]
如果采用提供对指定地点的访问和复制的方式发布可执行码或目标码，那么，提供对同一地点的访问和复制源码可以算作源码的发布，即使第三方不强求与目标码一起复制源码。
4. 除非你明确按许可证提出的要求去做，否则你不能复制，修改，转发许可证和发布程序。任何试图用其他方式复制，修改，转发许可证和发布程序是无效的。而且将自动结束许可证赋予你的权利。然而，对那些从你那里按许可证条款得到副本和权利的人们，只要他们继续全面履行条款，许可证赋予他们的权利仍然有效。
5. 你没有在许可证上签字，因而你没有必要一定接受这一许可证。然而，没有任何其他东西赋予你修改和发布程序及其衍生作品的权利。如果你不接受许可证，这些行为是法律禁止的。因此，如果你修改或发布程序（或任何基于程序的作品），你就表明你接受这一许可证以及它的所有有关复制，发布和修改程序或基于程序的作品的条款和条件。
6. 每当你重新发布程序（或任何基于程序的作品）时，接受者自动从原始许可证颁发者那里接到受这些条款和条件支配的复制，发布或修改程序的许可证。你不可以对接受者履行这里赋予他们的权利强加其他限制。你也没有强求第三方履行许可证条款的义务。
7. 如果由于法院判决或违反专利的指控或任何其他原因（不限于专利问题）的结果，强加于你的条件（不管是法院判决，协议或其他）和许可证的条件有冲突。他们也不能用许可证条款为你开脱。在你不能同时满足本许可证规定的义务及其他相关的义务时，作为结果，你可以根本不发布程序。例如，如果某一专利许可证不允许所有那些直接或间接从你那里接受副本的人们在不付专利费的情况下重新发布程序，唯一能同时满足两方面要求的办法是停止发布程序。
如果本条款的任何部分在特定的环境下无效或无法实施，就使用条款的其余部分。并将条款作为整体用于其他环境。
本条款的目的不在于引诱你侵犯专利或其他财产权的要求，或争论这种要求的有效性。本条款的主要目的在于保护自由软件发布系统的完整性。它是通过通用公共许可证的应用来实现的。许多人坚持应用这一系统，已经为通过这一系统发布大量自由软件作出慷慨的供献。作者／捐献者有权决定他／她是否通过任何其他系统发布软件。许可证持有人不能强制这种选择。
本节的目的在于明确说明许可证其余部分可能产生的结果。
8. 如果由于专利或者由于有版权的接口问题使程序在某些国家的发布和使用受到限止，将此程序置于许可证约束下的原始版权拥有者可以增加限止发布地区的条款，将这些国家明确排除在外。并在这些国家以外的地区发布程序。在这种情况下，许可证包含的限止条款和许可证正文一样有效。
9. 自由软件基金会可能随时出版通用公共许可证的修改版或新版。新版和当前的版本在原则上保持一致，但在提到新问题时或有关事项时，在细节上可能出现差别。
每一版本都有不同的版本号。如果程序指定适用于它的许可证版本号以及“任何更新的版本”。你有权选择遵循指定的版本或自由软件基金会以后出版的新版本，如果程序未指定许可证版本，你可选择自由软件基金会已经出版的任何版本。
10. 如果你愿意将程序的一部分结合到其他自由程序中，而它们的发布条件不同。写信给作者，要求准予使用。如果是自由软件基金会加以版权保护的软件，写信给自由软件基金会。我们有时会作为例外的情况处理。我们的决定受两个主要目标的指导。这两个主要目标是：我们的自由软件的衍生作品继续保持自由状态。以及从整体上促进软件的共享和重复利用。
没有担保
11. 由于程序准予免费使用，在适用法准许的范围内，对程序没有担保。除非另有书面说明，版权所有者和／或其他提供程序的人们“一样”不提供任何类型的担保。不论是明确的，还是隐含的。包括但不限于隐含的适销和适合特定用途的保证。全部的风险，如程序的质量和性能问题都由你来承担。如果程序出现缺陷，你承担所有必要的服务，修复和改正的费用。
12. 除非适用法或书面协议的要求，在任何情况下，任何版权所有者或任何按许可证条款修改和发布程序的人们都不对你的损失负有任何责任。包括由于使用或不能使用程序引起的任何一般的，特殊的，偶然发生的或重大的损失（包括但不限于数据的损失，或者数据变得不精确，或者你或第三方的持续的损失，或者程序不能和其他程序协调运行等）。即使版权所有者和其他人提到这种损失的可能性也不例外。
最后的条款和条件
如何将这些条款用到你的新程序
如果你开发了新程序，而且你需要它得到公众最大限度的利用。要做到这一点的最好办法是将它变为自由软件。使得每个人都能在遵守条款的基础上对它进行修改和重新发布。
为了做到这一点，给程序附上下列声明。最安全的方式是将它放在每个源程序的开头，以便最有效地传递拒绝担保的信息。每个文件至少应有“版权所有”
行以及在什么地方能看到声明全文的说明。
<用一行空间给出程序的名称和它用来做什么的简单说明>
版权所有（C） 19XX <作者姓名>
这一程序是自由软件，你可以遵照自由软件基金会出版的GNU通用公共许可证条款来修改和重新发布这一程序。或者用许可证的第二版，或者（根据你的选择）用任何更新的版本。
发布这一程序的目的是希望它有用，但没有任何担保。甚至没有适合特定目的的隐含的担保。更详细的情况请参阅GNU通用公共许可证。
你应该已经和程序一起收到一份GNU通用公共许可证的副本。如果还没有，写信给：
the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA02139, USA
还应加上如何和你保持联系的信息。
如果程序以交互方式进行工作，当它开始进入交互方式工作时，使它输出类似下面的简短声明：
Gnomovision 第69版， 版权所有（C） 19XX， 作者姓名，Gnomovision绝对没有担保。 要知道详细情况，请输入\'show w\'.这是自由软件，欢迎你遵守一定的条件重新发布它，要知道详细情况，请输入\'show c\'.
假设的命令\'show w\'和\'show c\'应显示通用公共许可证的相应条款。当然，你使用的命令名称可以不同于\'show w\'和\'show c\'.根据你的程序的具体情况，也可以用菜单或鼠标选项来显示这些条款。[page]
如果需要，你应该取得你的上司（如果你是程序员）或你的学校签署放弃程序版权的声明。下面只是一个例子，你应该改变相应的名称：
Yoyodyne公司以此方式放弃James Harker所写的 Gnomovision程序的全部版权利益。
1989.4.1
Ty coon付总裁
这一许可证不允许你将程序并入专用程序。如果你的程序是一个子程序库。
你可能会认为用库的方式和专用应用程序连接更有用。如果这是你想做的事，使用GNU库通用公共许可证代替本许可证。
GNU GENERAL PUBLIC LICENSE
Version 2, June 1991
Copyright （C） 1989, 1991 Free Software Foundation, Inc. 675 Mass Ave, Cambridge, MA 02139, USA
Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.
Preamble
the licenses for most software are designed to take away your freedom to share and change it. By contrast, the GNU General Public License is intended to guarantee your freedom to share and change free software——to make sure the software is free for all its users. This General Public License applies to most of the Free Software Foundation\'\'s software and to any other program whose authors commit to using it. （Some other Free Software Foundation software is covered by the GNU Library General Public License instead.） You can apply it to your programs, too.
When we speak of free software, we are referring to freedom, not price. Our General Public Licenses are designed to make sure that you have the freedom to distribute copies of free software （and charge for this service if you wish）, that you receive source code or can get it if you want it, that you can change the software or use pieces of it in new free programs; and that you know you can do these things.
To protect your rights, we need to make restrictions that forbid anyone to deny you these rights or to ask you to surrender the rights. these restrictions translate to certain responsibilities for you if you distribute copies of the software, or if you modify it.
For example, if you distribute copies of such a program, whether gratis or for a fee, you must give the recipients all the rights that you have. You must make sure that they, too, receive or can get the source code. And you must show them these terms so they know their rights.
We protect your rights with two steps: （1） copyright the software, and（2） offer you this license which gives you legal permission to copy, distribute and/or modify the software.
Also, for each author\'\'s protection and ours, we want to make certain that everyone understands that there is no warranty for this free software. If the software is modified by someone else and passed on, we want its recipients to know that what they have is not the original, so that any problems introduced by others will not reflect on the original authors\'\' reputations.
Finally, any free program is threatened constantly by software patents. We wish to avoid the danger that redistributors of a free program will individually obtain patent licenses, in effect making the program proprietary. To prevent this, we have made it clear that any patent must be licensed for everyone\'\'s free use or not licensed at all.
the precise terms and conditions for copying, distribution and modification follow.
GNU GENERAL PUBLIC LICENSE TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
0. This License applies to any program or other work which contains a notice placed by the copyright holder saying it may be distributed under the terms of this General Public License. The \"Program\", below, refers to any such program or work, and a \"work based on the Program\" means either the Program or any derivative work under copyright law: that is to say, a work containing the Program or a portion of it, either verbatim or with modifications and/or translated into another language. （Hereinafter, translation is included without limitation in the term \"modification\".） Each licensee is addressed as \"you\".
Activities other than copying, distribution and modification are not covered by this License; they are outside its scope. The act of running the Program is not restricted, and the output from the Program is covered only if its contents constitute a work based on the Program （independent of having been made by running the Program）. Whether that is true depends on what the Program does.
1. You may copy and distribute verbatim copies of the Program\'\'s source code as you receive it, in any medium, provided that you conspicuously and appropriately publish on each copy an appropriate copyright notice and disclaimer of warranty; keep intact all the notices that refer to this License and to the absence of any warranty; and give any other recipients of the Program a copy of this License along with the Program.
You may charge a fee for the physical act of transferring a copy, and you may at your option offer warranty protection in exchange for a fee.
2. You may modify your copy or copies of the Program or any portion of it, thus forming a work based on the Program, and copy and distribute such modifications or work under the terms of Section 1 above, provided that you also meet all of these conditions:[page]
a） You must cause the modified files to carry prominent notices stating that you changed the files and the date of any change.
b） You must cause any work that you distribute or publish, that in whole or in part contains or is derived from the Program or any part thereof, to be licensed as a whole at no charge to all third parties under the terms of this License.
c） If the modified program normally reads commands interactively when run, you must cause it, when started running for such interactive use in the most ordinary way, to print or display an announcement including an appropriate copyright notice and a notice that there is no warranty （or else, saying that you provide a warranty） and that users may redistribute the program under these conditions, and telling the user how to view a copy of this License. （Exception: if the Program itself is interactive but does not normally print such an announcement, your work based on the Program is not required to print an announcement.）
these requirements apply to the modified work as a whole. If identifiable sections of that work are not derived from the Program, and can be reasonably considered independent and separate works in themselves, then this License, and its terms, do not apply to those sections when you distribute them as separate works. But when you distribute the same sections as part of a whole which is a work based on the Program, the distribution of the whole must be on the terms of this License, whose permissions for other licensees extend to the entire whole, and thus to each and every part regardless of who wrote it.
Thus, it is not the intent of this section to claim rights or contest your rights to work written entirely by you; rather, the intent is to exercise the right to control the distribution of derivative or collective works based on the Program.
In addition, mere agGREgation of another work not based on the Program with the Program （or with a work based on the Program） on a volume of a storage or distribution medium does not bring the other work under the scope of this License.
3. You may copy and distribute the Program （or a work based on it, under Section 2） in object code or executable form under the terms of Sections 1 and 2 above provided that you also do one of the following:
a） Accompany it with the complete corresponding machine-readable source code, which must be distributed under the terms of Sections 1 and 2 above on a medium customarily used for software interchange; or,
b） Accompany it with a written offer, valid for at least three years, to give any third party, for a charge no more than your cost of physically performing source distribution, a complete machine-readable copy of the corresponding source code, to be distributed under the terms of Sections 1 and 2 above on a medium customarily used for software interchange; or,
c） Accompany it with the information you received as to the offer to distribute corresponding source code. （This alternative is allowed only for noncommercial distribution and only if you received the program in object code or executable form with such an offer, in accord with Subsection b above.）
the source code for a work means the preferred form of the work for making modifications to it. For an executable work, complete source code means all the source code for all modules it contains, plus any associated interface definition files, plus the scripts used to control compilation and installation of the executable. However, as a special exception, the source code distributed need not include anything that is normally distributed （in either source or binary form） with the major components （compiler, kernel, and so on） of the operating system on which the executable runs, unless that component itself accompanies the executable.
If distribution of executable or object code is made by offering access to copy from a designated place, then offering equivalent access to copy the source code from the same place counts as distribution of the source code, even though third parties are not compelled to copy the source along with the object code.
4. You may not copy, modify, sublicense, or distribute the Program except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense or distribute the Program is void, and will automatically terminate your rights under this License. However, parties who have received copies, or rights, from you under this License will not have their licenses terminated so long as such parties remain in full compliance.
5. You are not required to accept this License, since you have not signed it. However, nothing else grants you permission to modify or distribute the Program or its derivative works. These actions are prohibited by law if you do not accept this License. therefore, by modifying or distributing the Program （or any work based on the Program）, you indicate your acceptance of this License to do so, and all its terms and conditions for copying, distributing or modifying the Program or works based on it.[page]
6. Each time you redistribute the Program （or any work based on the Program）, the recipient automatically receives a license from the original licensor to copy, distribute or modify the Program subject to these terms and conditions. You may not impose any further restrictions on the recipients\'\' exercise of the rights granted herein. You are not responsible for enforcing compliance by third parties to this License.
7. If, as a consequence of a court judgment or allegation of patent infringement or for any other reason （not limited to patent issues）, conditions are imposed on you （whether by court order, aGREement or otherwise） that contradict the conditions of this License, they do not excuse you from the conditions of this License. If you cannot distribute so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not distribute the Program at all. For example, if a patent license would not permit royalty-free redistribution of the Program by all those who receive copies directly or indirectly through you, then the only way you could satisfy both it and this License would be to refrain entirely from distribution of the Program.
If any portion of this section is held invalid or unenforceable under any particular circumstance, the balance of the section is intended to apply and the section as a whole is intended to apply in other circumstances.
It is not the purpose of this section to induce you to infringe any patents or other property right claims or to contest validity of any such claims; this section has the sole purpose of protecting the integrity of the free software distribution system, which is implemented by public license practices. Many people have made generous contributions to the wide range of software distributed through that system in reliance on consistent application of that system; it is up to the author/donor to decide if he or she is willing to distribute software through any other system and a licensee cannot impose that choice.
This section is intended to make thoroughly clear what is believed to be a consequence of the rest of this License.
8. If the distribution and/or use of the Program is restricted in certain countries either by patents or by copyrighted interfaces, the original copyright holder who places the Program under this License may add an explicit geographical distribution limitation excluding those countries, so that distribution is permitted only in or among countries not thus excluded. In such case, this License incorporates the limitation as if written in the body of this License.
9. the Free Software Foundation may publish revised and/or new versions of the General Public License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns.
Each version is given a distinguishing version number. If the Program specifies a version number of this License which applies to it and \"any later version\", you have the option of following the terms and conditions either of that version or of any later version published by the Free Software Foundation. If the Program does not specify a version number of this License, you may choose any version ever published by the Free Software Foundation.
10. If you wish to incorporate parts of the Program into other free programs whose distribution conditions are different, write to the author to ask for permission. For software which is copyrighted by the Free Software Foundation, write to the Free Software Foundation; we sometimes make exceptions for this. Our decision will be guided by the two goals of preserving the free status of all derivatives of our free software and of promoting the sharing and reuse of software generally.
NO WARRANTY
11. BECAUSE the PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY FOR the PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OtheRWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE the PROGRAM \"AS IS\" WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, the IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. the ENTIRE RISK AS TO the QUALITY AND PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME the COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OtheR PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE the PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF the USE OR INABILITY TO USE THE PROGRAM （INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF the PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS）, EVEN IF SUCH HOLDER OR OtheR PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.[page]
END OF TERMS AND CONDITIONS
How to Apply these Terms to Your New Programs
If you develop a new program, and you want it to be of the GREatest possible use to the public, the best way to achieve this is to make it free software which everyone can redistribute and change under these terms.
To do so, attach the following notices to the program. It is safest to attach them to the start of each source file to most effectively convey the exclusion of warranty; and each file should have at least the \"copyright\" line and a pointer to where the full notice is found.
Copyright （C） 19yy
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or（at your option） any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
Also add information on how to contact you by electronic and paper mail.
If the program is interactive, make it output a short notice like this when it starts in an interactive mode:
Gnomovision version 69, Copyright （C） 19yy name of author Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w\'\'. This is free software, and you are welcome to redistribute it under certain conditions; type `show c\'\' for details.
the hypothetical commands `show w\'\' and `show c\'\' should show the appropriate parts of the General Public License. Of course, the commands you use may be called something other than `show w\'\' and `show c\'\'; they could even be mouse-clicks or menu items——whatever suits your program.
You should also get your employer （if you work as a programmer） or your school, if any, to sign a \"copyright disclaimer\" for the program, if necessary. Here is a sample; alter the names:
Yoyodyne, Inc., hereby disclaims all copyright interest in the program `Gnomovision\'\' （which makes passes at compilers） written by James Hacker.
1, April 1989 Ty Coon, President of Vice
This General Public License does not permit incorporating your program into proprietary programs. If your program is a subroutine library, you may consider it more useful to permit linking proprietary applications with the library. If this is what you want to do, use the GNU Library General Public License instead of this License.
