iii
In other cases, permission to use a particular library in non-free programs enables a
greater number of people to use a large body of free software. For example, permission
to use the GNU C Library in non-free programs enables many more people to use the
whole GNU operating system, as well as its variant, the GNU/Linux operating system.
Although the Lesser General Public License is Less protective of the users’ freedom, it
does ensure that the user of a program that is linked with the Library has the freedom
and the wherewithal to run that program using a modified version of the Library.
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, whereas the
latter must be combined with the library in order to run.
GNU LESSER GENERAL PUBLIC LICENSE
TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND
MODIFICATION
0. This License Agreement applies to any software library or other program which
contains a notice placed by the copyright holder or other authorized party saying it
may be distributed under the terms of this Lesser 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 combine 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) Use a suitable shared library mechanism for linking with the Library. A
suitable mechanism is one that (1) uses at run time a copy of the library already
present on the user’s computer system, rather than copying library functions
into the executable, and (2) will operate properly with a modified version of the
library, if the user installs one, as long as the modified version is interface-
compatible with the version that the work was made with.
c) 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.
d) 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.
e) 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 materials to be 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.
Содержание BD-S473
Страница 287: ...xviii ...