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.
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: 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
