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
236
GNU GENERAL PUBLIC LICENSE
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