copying

A serial programming source code for linux

GNU GENERAL PUBLIC LICENSE
Version 2, June 1991 

Copyright (C) 1989, 1991 Free Software Foundation, Inc.  
59 Temple Place - Suite 330, Boston, MA  02111-1307, 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
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When we speak of free software, we are referring to freedom, not price. Our
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wish), that you receive source code or can get it if you want it, that you
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To protect your rights, we need to make restrictions that forbid anyone to
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For example, if you distribute copies of such a program, whether gratis or
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We protect your rights with two steps: (1) copyright the software, and (2)
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Finally, any free program is threatened constantly by software patents. We
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The precise terms and conditions for copying, distribution and modification
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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
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program or work, and a "work based on the Program" means either the Program
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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
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is not restricted, and the output from the Program is covered only if its
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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
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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
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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
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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
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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
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and every part regardless of who wrote it. Thus, it is not the intent of
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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
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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
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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
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corresponding source code, to be distributed under the terms of Sections 1
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c) Accompany it with the information you received as to the offer to
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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
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5. You are not required to accept this License, since you have not signed
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Program or its derivative works. These actions are prohibited by law if you
do not accept this License. Therefore, by modifying or distributing the