User manual

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
54