China DOS Union

GNU GPL -- GNU General Public License

Version 2, June 1991

Copyright (C) 1989, 1991 Free Software foundation,Inc．675 Mass Ave，Cambridge，MAO2139，USA Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is absolutely not allowed.

Preamble

Most software licenses are designed to take away your freedom to share and modify software. By contrast, the GNU General Public License is intended to guarantee your freedom to share and modify free software -- to make sure free software is free for all its users. The GPL applies to most of the Free Software Foundation's software, and to software developed by authors who have undertaken the obligation of using it. (Some other Free Software Foundation software is covered by the GNU Library General Public License instead.) You can also apply it to your programs.

When we speak of free software, we mean freedom, not price. Our GNU General Public License is designed to make sure you have the freedom to distribute copies of free software (and charge for this service if you wish); to make sure you can receive the source code or get it when you need it; to make sure you can modify the software or use parts of it in new free software; and also to make sure you know you can do these things. To protect your rights, we need to make provisions: to forbid anyone from denying your rights, or asking you to give up those rights. If you modify free software or distribute copies of the software, these provisions become your responsibilities. For example, if you distribute copies of such a program, whether for a fee or free of charge, you must give the recipients all the rights you have; you must make sure they can receive or obtain the source code; and show them these terms so that they know they have these rights.


We protect your rights with two measures.

(1) Give the software copyright protection.

(2) Provide you with a license. It gives you legal permission to copy, distribute and modify the software. Likewise, to protect every author and ourselves, we need to make it clear to everyone that free software has no warranty. If the software is modified by someone else and then passed on, we need its recipients to understand that what they have received is not the original free software. Any problems introduced by others should not damage the reputation of the original authors.

Finally, any free software is constantly threatened by software patents. We wish to avoid the risk that redistributors of free software obtain patent licenses individually, in effect turning the software into proprietary software. To prevent this, we must make it clear: any patent must be licensed for everyone's free use, or not licensed at all.
　　
Terms and conditions for copying, distribution and modification

　　0. This License applies to any program or other work which contains a notice by the copyright holder stating that the program or work may be distributed under the terms of the GPL. The "Program" mentioned below refers to any such program or work. A "work based on the Program" refers to the Program or any derivative work subject to copyright law.
　　That is, a work containing the Program or a portion of the Program. It may be verbatim, or modified and/or translated into another language (program). Hereinafter, translation is included in the term modification. Each licensee is addressed as "you".

　　The license terms do not apply to activities other than copying, distribution and modification. Those activities are outside the scope of these terms. The act of running the Program is not restricted by the terms. This clause applies only when the output of the Program constitutes the content of a work based on the Program (if the Program is merely run, then it is irrelevant). Whether it generally applies depends on what the Program is specifically used to do.

　　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 a copyright notice and a disclaimer of warranty, keep intact the notice of this License and the notice of no warranty, and give each other recipient of the Program a copy of this License together with the Program.

　　You may charge a fee for the physical act of transferring a copy. You also have the right to choose to offer warranty protection in exchange for a fee.

　　2. You may modify one or several copies of the Program or any portion of the Program, thus forming a work based on the Program. You may copy and distribute this modified Program or work according to the requirements of Section 1 above, provided that you also meet all the conditions below.

　　a) You must attach clear notices to the modified files stating that you modified the files and the specific dates of modification.

　　b) You must cause any work you distribute or publish (which contains all or part of the Program, or contains a work derived from all or part of the Program) to be licensed as a whole, at no charge to third parties, under the terms of this License.

　　c) If the modified program reads commands interactively when run, you must cause it, when it starts entering ordinary interactive use, to print or display an announcement: including an appropriate copyright notice and a notice of no warranty (or a notice that you provide a warranty); an explanation that users may redistribute the program under the terms of this License; and telling users how to see a copy of this License. (Exception: if the original Program works interactively but does not print such an announcement, then your work based on the Program does not need to print an announcement either.)

　　These requirements apply to the modified work as a whole. If part of the work can be identified as not being a derivative of the Program, and can reasonably be considered independent and a different work, then when you distribute it as an independent work, it is not subject to this License or its terms. But when you distribute this part as part of a work based on the Program, the work as a whole will be subject to the terms of this License. The scope of use granted to other license holders extends to the entire product. That is, every part, regardless of who wrote it.

　　Thus, the intent of this section is not to claim rights to, or take away rights from, works written entirely by you. Rather, it is to exercise the right to control the distribution of collective works or derivative works based on the Program.

　　In addition, placing a work unrelated to the Program together with the Program or a work based on the Program on the same volume of a storage or distribution medium does not bring the other work within the scope of this License.

　　3. You may copy or distribute the Program (or a work based on the Program under Section 2) in object code or executable form, provided that you comply with Sections 1 and 2 above and also meet one of the following three conditions.

　　a) Accompany the object code with the complete corresponding machine-readable source code, on a medium customarily used for software interchange. Distribution of this source code must comply with the requirements of Sections 1 and 2 above. Or

　　b) Accompany the object code, on a medium customarily used for software interchange, with a written offer to provide any third party with the corresponding machine-readable source code. This offer must be valid for not less than three years, and the charge must not exceed the actual cost of physically distributing the source code. Distribution of the source code must comply with the requirements of Sections 1 and 2 above. Or

　　c) Accompany the object code with the information you received as to the offer to distribute the source code. (This clause applies only to noncommercial distribution, and only if you received the Program in object code or executable form together with an offer as required by Subsection b).)

　　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 includes: all source programs for all modules, plus the associated interface definitions, plus the script used to control installation and compilation of the executable work. As a special exception, the distributed source code need not include any major components of the operating system on which the executable code runs that are normally distributed (such as the compiler, kernel, etc.). Unless those components are combined with the executable work.

　　If distribution of executable code or object code is made by offering access to copy from a designated place, then offering access to copy the source code from the same place counts as distribution of the source code, even though third parties are not required to copy the source code together with the object code.

　　4. Except as expressly required by the License, you may not copy, modify, sublicense, or distribute the Program. Any attempt to copy, modify, sublicense, or distribute the Program by any other means is invalid. Moreover, it will automatically terminate the rights granted to you by this License. However, for those who have received copies and rights from you under the terms of this License, the rights granted to them by the License remain valid as long as they continue to fully comply with the terms.

　　5. You have not signed the License, and therefore you are not necessarily required to accept this License. However, nothing else grants you the right to modify and distribute the Program and its derivative works. If you do not accept the License, these actions are prohibited by law. Therefore, if you modify or distribute the Program (or any work based on the Program), you indicate your acceptance of this License and all its terms and conditions concerning copying, distribution, and modification of the Program or works based on the Program.

　　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 under these terms and conditions. You may not impose any further restrictions on the recipients' exercise of the rights granted to them here. You also have no obligation to require third parties to comply with the terms of the 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 judgment, agreement, or otherwise) that conflict with the conditions of this License, they do not excuse you from the conditions of the License.

　　If you cannot simultaneously satisfy the obligations under this License and other relevant obligations, then as a consequence, you may not distribute the Program at all. For example, if a patent license would not allow all those who receive copies directly or indirectly from you to redistribute the Program without paying patent royalties, the only way to satisfy both requirements at the same time is to stop distributing the Program.

　　If any part of this section is invalid or unenforceable under particular circumstances, the remainder of the section is used, and the section as a whole applies in other circumstances.

　　The purpose of this section is not to induce you to infringe any patent or other property-right claims, or to dispute the validity of such claims. The main purpose of this section is to protect the integrity of the free software distribution system. It is achieved through the application of the General Public License. Many people, by consistently applying this system, have made generous contributions to the large amount of free software distributed through this system. The author/donor has the right to decide whether he/she distributes software through any other system. A license holder cannot force that choice.

　　The purpose of this section is to make clear the possible consequences of the rest of the License.

　　8. If the distribution and use of the Program in certain countries are restricted because of patents or because of copyrighted interfaces, the original copyright holder who places this Program under the License may add terms limiting the distribution region, explicitly excluding those countries, and distribute the Program in regions outside those countries. In such case, the restrictive terms included in the License are as effective as the body of the License.

　　9. The Free Software Foundation may publish revised or new versions of the General Public License at any time. New versions will remain consistent in principle with the current version, but may differ in details when addressing new problems or related matters.

　　Each version has a different version number. If the Program specifies the version number of the License applicable to it and "any later version", you have the right to choose to follow the specified version or a later version published by the Free Software Foundation. If the Program does not specify a license version number, you may choose any version already published by the Free Software Foundation.

　　10. If you wish to incorporate part of the Program into other free programs whose distribution conditions are different, write to the author to ask for permission. For software copyrighted by the Free Software Foundation, write to the Free Software Foundation. We sometimes handle this as an exception. Our decision is guided by two main goals. These two main goals are: to keep derivative works of our free software free, and to promote the sharing and reuse of software as a whole.

　　No Warranty

　　11. Because the Program is licensed for free use, there is no warranty for the Program, to the extent permitted by applicable law. Unless otherwise stated in writing, the copyright holders and/or other parties providing the Program provide the Program "as is" without warranty of any kind. Whether 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 borne by you. If the Program proves defective, you assume the cost of all necessary servicing, repair and correction.

　　12. Unless required by applicable law or written agreement, in no event will any copyright holder, or any party who modifies and distributes the Program under the terms of the License, be liable to you for your losses. 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, data becoming inaccurate, losses sustained by you or third parties, or the Program failing to operate with other programs, etc.). Even if the copyright holder or other party has been advised of the possibility of such damages.

　　

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 used by the public to the greatest extent possible.

　　The best way to do this is to make it free software. So that everyone can modify and redistribute it on the basis of complying with the terms. To do this, attach the following notices to the Program. The safest way is to put them at the beginning of each source file, so as to convey the disclaimer of warranty most effectively. Each file should at least have a "copyright" line and an explanation of where the full notice can be seen.

　　＜Use one line of space to give the program's name and a brief description of what it does＞

　　Copyright (C) 19xx (＜author's name＞

　　This program is free software; you can modify and redistribute it in accordance with the terms of the GNU General Public License 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. Not even the implied warranty of 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 the Program.

　　If not, write to:

　　The Free Software Foundation，Inc，，675 Mass Ave，Cambridge， MAO2139，USA You should also add information on how to contact you.

　　If the program works interactively, when it starts entering interactive mode, make it output a short notice similar to the following ll

Gnomovision version 69, Copyright (C) 19XX, author's name,

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; for details type 'Show c'.

The hypothetical commands ‘shovr w’ and ‘show c’ should show the corresponding terms of the General Public License. Of course, the command names you use may be different from ‘show w’ and ‘show c，. Depending on the specific situation of your program, these terms may also be displayed by using menu or mouse options.

If necessary, you should have your employer (if you are a programmer) or your school sign a statement relinquishing copyright in the program. The following is only an example; you should change the corresponding names:

Ynyodyne company hereby relinquishes all copyright interest in the Gnomovision program

written by James Harker.

＜Ty coon signature＞, 1989.4.1

Ty coon Vice President

This License does not permit you to incorporate the Program into proprietary programs. If your program is a subroutine library. You may think it is more useful to link proprietary applications with the library. If this is what you want to do, use the GNU Library General Public License instead of this License.

FreeDOS is GNU GPL software, after all; I hope everyone will work together to develop it!