A couple more 'int' to UWORD conversions I had not merged into my previous checkin.

[wxWidgets.git] / docs / lgpl.txt

	  GNU LIBRARY GENERAL PUBLIC LICENSE
	  ==================================
                Version 2, June 1991

 Copyright (C) 1991 Free Software Foundation, Inc.
                    675 Mass Ave, Cambridge, MA 02139, USA
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.

[This is the first released version of the library GPL.  It is
 numbered 2 because it goes with version 2 of the ordinary GPL.]

                        Preamble

The licenses for most software are designed to take away your
freedom to share and change it.  By contrast, the GNU General
Public Licenses are intended to guarantee your freedom to share
and change free software--to make sure the software is free for
all its users.

This license, the Library General Public License, applies to
some specially designated Free Software Foundation software, and
to any other libraries whose authors decide to use it.  You can
use it for your libraries, 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 library, or if you
modify it.

For example, if you distribute copies of the library, whether
gratis or for a fee, you must give the recipients all the rights
that we gave you.  You must make sure that they, too, receive or
can get the source code.  If you link a program with the
library, you must provide complete object files to the
recipients so that they can relink them with the library, after
making changes to the library and recompiling it.  And you must
show them these terms so they know their rights.

Our method of protecting your rights has two steps: (1)
copyright the library, and (2) offer you this license which
gives you legal permission to copy, distribute and/or modify the
library.

Also, for each distributor's protection, we want to make certain
that everyone understands that there is no warranty for this
free library.  If the library is modified by someone else and
passed on, we want its recipients to know that what they have is
not the original version, 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 companies
distributing free software will individually obtain patent
licenses, thus in effect transforming the program into
proprietary software.  To prevent this, we have made it clear
that any patent must be licensed for everyone's free use or not
licensed at all.

Most GNU software, including some libraries, is covered by the
ordinary GNU General Public License, which was designed for
utility programs.  This license, the GNU Library General Public
License, applies to certain designated libraries.  This license
is quite different from the ordinary one; be sure to read it in
full, and don't assume that anything in it is the same as in the
ordinary license.

The reason we have a separate public license for some libraries
is that they blur the distinction we usually make between
modifying or adding to a program and simply using it.  Linking a
program with a library, without changing the library, is in some
sense simply using the library, and is analogous to running a
utility program or application program.  However, in a textual
and legal sense, the linked executable is a combined work, a
derivative of the original library, and the ordinary General
Public License treats it as such.

Because of this blurred distinction, using the ordinary General
Public License for libraries did not effectively promote
software sharing, because most developers did not use the
libraries.  We concluded that weaker conditions might promote
sharing better.

However, unrestricted linking of non-free programs would deprive
the users of those programs of all benefit from the free status
of the libraries themselves.  This Library General Public
License is intended to permit developers of non-free programs to
use free libraries, while preserving your freedom as a user of
such programs to change the free libraries that are incorporated
in them.  (We have not seen how to achieve this as regards
changes in header files, but we have achieved it as regards
changes in the actual functions of the Library.)  The hope is
that this will lead to faster development of free libraries.

The precise terms and conditions for copying, distribution and
modification follow.  Pay close attention to the difference
between a "work based on the library" and a "work that uses the
library".  The former contains code derived from the library,
while the latter only works together with the library.

Note that it is possible for a library to be covered by the
ordinary General Public License rather than by this special one.

                GNU LIBRARY GENERAL PUBLIC LICENSE
 TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION

0. This License Agreement applies to any software library which
contains a notice placed by the copyright holder or other
authorized party saying it may be distributed under the terms of
this Library General Public License (also called "this
License").  Each licensee is addressed as "you".

A "library" means a collection of software functions and/or data
prepared so as to be conveniently linked with application
programs (which use some of those functions and data) to form
executables.

The "Library", below, refers to any such software library or
work which has been distributed under these terms.  A "work
based on the Library" means either the Library or any derivative
work under copyright law: that is to say, a work containing the
Library or a portion of it, either verbatim or with
modifications and/or translated straightforwardly into another
language.  (Hereinafter, translation is included without
limitation in the term "modification".)

"Source code" for a work means the preferred form of the work
for making modifications to it.  For a library, 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 library.

Activities other than copying, distribution and modification are
not covered by this License; they are outside its scope.  The
act of running a program using the Library is not restricted,
and output from such a program is covered only if its contents
constitute a work based on the Library (independent of the use
of the Library in a tool for writing it).  Whether that is true
depends on what the Library does and what the program that uses
the Library does.
  
1. You may copy and distribute verbatim copies of the Library's
complete 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 distribute a copy of this License
along with the Library.

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 Library or any
portion of it, thus forming a work based on the Library, 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) The modified work must itself be a software library.

    b) You must cause the files modified to carry prominent notices
    stating that you changed the files and the date of any change.

    c) You must cause the whole of the work to be licensed at no
    charge to all third parties under the terms of this License.

    d) If a facility in the modified Library refers to a function or a
    table of data to be supplied by an application program that uses
    the facility, other than as an argument passed when the facility
    is invoked, then you must make a good faith effort to ensure that,
    in the event an application does not supply such function or
    table, the facility still operates, and performs whatever part of
    its purpose remains meaningful.

    (For example, a function in a library to compute square roots has
    a purpose that is entirely well-defined independent of the
    application.  Therefore, Subsection 2d requires that any
    application-supplied function or table used by this function must
    be optional: if the application does not supply it, the square
    root function must still compute square roots.)

These requirements apply to the modified work as a whole.  If
identifiable sections of that work are not derived from the
Library, 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 Library, 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 Library.

In addition, mere aggregation of another work not based on the
Library with the Library (or with a work based on the Library)
on a volume of a storage or distribution medium does not bring
the other work under the scope of this License.

3. You may opt to apply the terms of the ordinary GNU General
Public License instead of this License to a given copy of the
Library.  To do this, you must alter all the notices that refer
to this License, so that they refer to the ordinary GNU General
Public License, version 2, instead of to this License.  (If a
newer version than version 2 of the ordinary GNU General Public
License has appeared, then you can specify that version instead
if you wish.)  Do not make any other change in these notices.
 
Once this change is made in a given copy, it is irreversible for
that copy, so the ordinary GNU General Public License applies to
all subsequent copies and derivative works made from that copy.

This option is useful when you wish to copy part of the code of
the Library into a program that is not a library.

4. You may copy and distribute the Library (or a portion or
derivative of it, under Section 2) in object code or executable
form under the terms of Sections 1 and 2 above provided that you
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.

If distribution of 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 satisfies the
requirement to distribute the source code, even though third
parties are not compelled to copy the source along with the
object code.

5. A program that contains no derivative of any portion of the
Library, but is designed to work with the Library by being
compiled or linked with it, is called a "work that uses the
Library".  Such a work, in isolation, is not a derivative work
of the Library, and therefore falls outside the scope of this
License.

However, linking a "work that uses the Library" with the Library
creates an executable that is a derivative of the Library
(because it contains portions of the Library), rather than a
"work that uses the library".  The executable is therefore
covered by this License. Section 6 states terms for distribution
of such executables.

When a "work that uses the Library" uses material from a header
file that is part of the Library, the object code for the work
may be a derivative work of the Library even though the source
code is not. Whether this is true is especially significant if
the work can be linked without the Library, or if the work is
itself a library.  The threshold for this to be true is not
precisely defined by law.

If such an object file uses only numerical parameters, data
structure layouts and accessors, and small macros and small
inline functions (ten lines or less in length), then the use of
the object file is unrestricted, regardless of whether it is
legally a derivative work.  (Executables containing this object
code plus portions of the Library will still fall under Section
6.)

Otherwise, if the work is a derivative of the Library, you may
distribute the object code for the work under the terms of
Section 6. Any executables containing that work also fall under
Section 6, whether or not they are linked directly with the
Library itself.
 
6. As an exception to the Sections above, you may also compile
or link a "work that uses the Library" with the Library to
produce a work containing portions of the Library, and
distribute that work under terms of your choice, provided that
the terms permit modification of the work for the customer's own
use and reverse engineering for debugging such modifications.

You must give prominent notice with each copy of the work that
the Library is used in it and that the Library and its use are
covered by this License.  You must supply a copy of this
License.  If the work during execution displays copyright
notices, you must include the copyright notice for the Library
among them, as well as a reference directing the user to the
copy of this License.  Also, you must do one of these things:

    a) Accompany the work with the complete corresponding
    machine-readable source code for the Library including whatever
    changes were used in the work (which must be distributed under
    Sections 1 and 2 above); and, if the work is an executable linked
    with the Library, with the complete machine-readable "work that
    uses the Library", as object code and/or source code, so that the
    user can modify the Library and then relink to produce a modified
    executable containing the modified Library.  (It is understood
    that the user who changes the contents of definitions files in the
    Library will not necessarily be able to recompile the application
    to use the modified definitions.)

    b) Accompany the work with a written offer, valid for at
    least three years, to give the same user the materials
    specified in Subsection 6a, above, for a charge no more
    than the cost of performing this distribution.

    c) If distribution of the work is made by offering access to copy
    from a designated place, offer equivalent access to copy the above
    specified materials from the same place.

    d) Verify that the user has already received a copy of these
    materials or that you have already sent this user a copy.

For an executable, the required form of the "work that uses the
Library" must include any data and utility programs needed for
reproducing the executable from it.  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.

It may happen that this requirement contradicts the license
restrictions of other proprietary libraries that do not normally
accompany the operating system.  Such a contradiction means you
cannot use both them and the Library together in an executable
that you distribute.
 
7. You may place library facilities that are a work based on the
Library side-by-side in a single library together with other
library facilities not covered by this License, and distribute
such a combined library, provided that the separate distribution
of the work based on the Library and of the other library
facilities is otherwise permitted, and provided that you do
these two things:

    a) Accompany the combined library with a copy of the same work
    based on the Library, uncombined with any other library
    facilities.  This must be distributed under the terms of the
    Sections above.

    b) Give prominent notice with the combined library of the fact
    that part of it is a work based on the Library, and explaining
    where to find the accompanying uncombined form of the same work.

8. You may not copy, modify, sublicense, link with, or
distribute the Library except as expressly provided under this
License.  Any attempt otherwise to copy, modify, sublicense,
link with, or distribute the Library is void, and will
automatically terminate your rights under this License.
However, parties who have received copies, or rights, from you
under this License will not have their licenses terminated so
long as such parties remain in full compliance.

9. You are not required to accept this License, since you have
not signed it.  However, nothing else grants you permission to
modify or distribute the Library or its derivative works.  These
actions are prohibited by law if you do not accept this
License.  Therefore, by modifying or distributing the Library
(or any work based on the Library), you indicate your acceptance
of this License to do so, and all its terms and conditions for
copying, distributing or modifying the Library or works based on
it.

10. Each time you redistribute the Library (or any work based on
the Library), the recipient automatically receives a license
from the original licensor to copy, distribute, link with or
modify the Library subject to these terms and conditions.  You
may not impose any further restrictions on the recipients'
exercise of the rights granted herein. You are not responsible
for enforcing compliance by third parties to this License.
 
11. 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
order, agreement or otherwise) that contradict the conditions of
this License, they do not excuse you from the conditions of this
License.  If you cannot distribute so as to satisfy
simultaneously your obligations under this License and any other
pertinent obligations, then as a consequence you may not
distribute the Library at all.  For example, if a patent license
would not permit royalty-free redistribution of the Library by
all those who receive copies directly or indirectly through you,
then the only way you could satisfy both it and this License
would be to refrain entirely from distribution of the Library.

If any portion of this section is held invalid or unenforceable
under any particular circumstance, the balance of the section is
intended to apply, and the section as a whole is intended to
apply in other circumstances.

It is not the purpose of this section to induce you to infringe
any patents or other property right claims or to contest
validity of any such claims; this section has the sole purpose
of protecting the integrity of the free software distribution
system which is implemented by public license practices.  Many
people have made generous contributions to the wide range of
software distributed through that system in reliance on
consistent application of that system; it is up to the
author/donor to decide if he or she is willing to distribute
software through any other system and a licensee cannot impose
that choice.

This section is intended to make thoroughly clear what is
believed to be a consequence of the rest of this License.

12. If the distribution and/or use of the Library is restricted
in certain countries either by patents or by copyrighted
interfaces, the original copyright holder who places the Library
under this License may add an explicit geographical distribution
limitation excluding those countries, so that distribution is
permitted only in or among countries not thus excluded.  In such
case, this License incorporates the limitation as if written in
the body of this License.

13. The Free Software Foundation may publish revised and/or new
versions of the Library General Public License from time to
time. Such new versions will be similar in spirit to the present
version, but may differ in detail to address new problems or
concerns.

Each version is given a distinguishing version number.  If the
Library specifies a version number of this License which applies
to it and "any later version", you have the option of following
the terms and conditions either of that version or of any later
version published by the Free Software Foundation.  If the
Library does not specify a license version number, you may
choose any version ever published by the Free Software
Foundation.

14. If you wish to incorporate parts of the Library into other
free programs whose distribution conditions are incompatible
with these, write to the author to ask for permission.  For
software which is copyrighted by the Free Software Foundation,
write to the Free Software Foundation; we sometimes make
exceptions for this.  Our decision will be guided by the two
goals of preserving the free status of all derivatives of our
free software and of promoting the sharing and reuse of software
generally.

                           NO WARRANTY

  15. BECAUSE THE LIBRARY IS LICENSED FREE OF CHARGE, THERE IS NO
WARRANTY FOR THE LIBRARY, TO THE EXTENT PERMITTED BY APPLICABLE LAW.
EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR
OTHER PARTIES PROVIDE THE LIBRARY "AS IS" WITHOUT WARRANTY OF ANY KIND,
EITHER 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
LIBRARY IS WITH YOU.  SHOULD THE LIBRARY PROVE DEFECTIVE, YOU ASSUME
THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.

  16. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY
AND/OR REDISTRIBUTE THE LIBRARY AS PERMITTED ABOVE, BE LIABLE TO YOU
FOR DAMAGES, INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL
DAMAGES ARISING OUT OF THE USE OR INABILITY TO USE THE
LIBRARY (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
FAILURE OF THE LIBRARY TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF
SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

                    END OF TERMS AND CONDITIONS

 Appendix: How to Apply These Terms to Your New Libraries

If you develop a new library, and you want it to be of the
greatest possible use to the public, we recommend making it free
software that everyone can redistribute and change.  You can do
so by permitting redistribution under these terms (or,
alternatively, under the terms of the ordinary General Public
License).

To apply these terms, attach the following notices to the
library.  It is safest to attach them to the start of each
source file to most effectively convey the exclusion of
warranty; and each file should have at least the "copyright"
line and a pointer to where the full notice is found.

    <one line to give the library's name and a brief idea of what it does.>
    Copyright (C) <year>  <name of author>

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public
    License along with this library; if not, write to the Free
    Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

Also add information on how to contact you by electronic and paper mail.

You should also get your employer (if you work as a programmer) or your
school, if any, to sign a "copyright disclaimer" for the library, if
necessary.  Here is a sample; alter the names:

  Yoyodyne, Inc., hereby disclaims all copyright interest in the
  library `Frob' (a library for tweaking knobs) written by James Random Hacker.

  <signature of Ty Coon>, 1 April 1990
  Ty Coon, President of Vice

That's all there is to it!