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 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