%local;
<!ENTITY % entities SYSTEM "entities.ent">
%entities;
- <!ENTITY % common SYSTEM "common/common.ent">
- %common;
+ <!ENTITY % idcommon SYSTEM "common/common.ent">
+ %idcommon;
]>
-<!-- $Id: book.xml,v 1.1 2007-01-10 09:44:20 adam Exp $ -->
+<!-- $Id: book.xml,v 1.16 2007-06-06 11:33:18 adam Exp $ -->
<book id="book">
<bookinfo>
- <title>pazpar2 - User's Guide and Reference</title>
+ <title>Pazpar2 - User's Guide and Reference</title>
<author>
<firstname>Sebastian</firstname><surname>Hammer</surname>
</author>
+ <author>
+ <firstname>Adam</firstname><surname>Dickmeiss</surname>
+ </author>
+ <author>
+ <firstname>Marc</firstname><surname>Cromme</surname>
+ </author>
+ <releaseinfo>&version;</releaseinfo>
<copyright>
<year>©right-year;</year>
<holder>Index Data</holder>
</copyright>
<abstract>
<simpara>
- pazpar2 - High-performance, user-interface
- user-interface independtent metasearching middleware.
+ Pazpar2 is a high-performance, user interface-independent, data
+ model-independent metasearching
+ middleware featuring merging, relevance ranking, record sorting,
+ and faceted results.
</simpara>
<simpara>
- This document is a guide and reference to pazpar version &version;.
+ This document is a guide and reference to Pazpar version &version;.
</simpara>
<simpara>
<inlinemediaobject>
<imageobject>
<imagedata fileref="common/id.png" format="PNG"/>
- </imageobject>
- <imageobject>
- <imagedata fileref="common/id.eps" format="EPS"/>
- </imageobject>
- </inlinemediaobject>
+ </imageobject>
+ <imageobject>
+ <imagedata fileref="common/id.eps" format="EPS"/>
+ </imageobject>
+ </inlinemediaobject>
</simpara>
</abstract>
</bookinfo>
-
+
<chapter id="introduction">
<title>Introduction</title>
-
<para>
- <ulink url="&url.pazpar2;">pazpar2</ulink> is.. To be written.
+ Pazpar2 is a stand-alone metasearch client with a webservice API, designed
+ to be used either from a browser-based client (JavaScript, Flash, Java,
+ etc.), from from server-side code, or any combination of the two.
+ Pazpar2 is a highly optimized client designed to
+ search many resources in parallel. It implements record merging,
+ relevance-ranking and sorting by arbitrary data content, and facet
+ analysis for browsing purposes. It is designed to be data model
+ independent, and is capable of working with MARC, DublinCore, or any
+ other XML-structured response format -- XSLT is used to normalize and extract
+ data from retrieval records for display and analysis. It can be used
+ against any server which supports the Z39.50 protocol. Proprietary
+ backend modules can be used to support a large number of other protocols
+ (please contact Index Data for further information about this).
+ </para>
+ <para>
+ Additional functionality such as
+ user management, attractive displays are expected to be implemented by
+ applications that use pazpar2. Pazpar2 is user interface independent.
+ Its functionality is exposed through a simple REST-style webservice API,
+ designed to be simple to use from an Ajax-enbled browser, Flash
+ animation, Java applet, etc., or from a higher-level server-side language
+ like PHP or Java. Because session information can be shared between
+ browser-based logic and your server-side scripting, there is tremendous
+ flexibility in how you implement your business logic on top of pazpar2.
+ </para>
+ <para>
+ Once you launch a search in pazpar2, the operation continues behind the
+ scenes. Pazpar2 connects to servers, carries out searches, and
+ retrieves, deduplicates, and stores results internally. Your application
+ code may periodically inquire about the status of an ongoing operation,
+ and ask to see records or other result set facets. Result become
+ available immediately, and it is easy to build end-user interfaces which
+ feel extremely responsive, even when searching more than 100 servers
+ concurrently.
+ </para>
+ <para>
+ Pazpar2 is designed to be highly configurable. Incoming records are
+ normalized to XML/UTF-8, and then further normalized using XSLT to a
+ simple internal representation that is suitable for analysis. By
+ providing XSLT stylesheets for different kinds of result records, you
+ can tune pazpar2 to work against different kinds of information
+ retrieval servers. Finally, metadata is extracted, in a configurable
+ way, from this internal record, to support display, merging, ranking,
+ result set facets, and sorting. Pazpar2 is not bound to a specific model
+ of metadata, such as DublinCore or MARC -- by providing the right
+ configuration, it can work with a number of different kinds of data in
+ support of many different applications.
+ </para>
+ <para>
+ Pazpar2 is designed to be efficient and scalable. You can set it up to
+ search several hundred targets in parallel, or you can use it to support
+ hundreds of concurrent users. It is implemented with the same attention
+ to performance and economy that we use in our indexing engines, so that
+ you can focus on building your application, without worrying about the
+ details of metasearch logic. You can devote all of your attention to
+ usability and let pazpar2 do what it does best -- metasearch.
+ </para>
+ <para>
+ If you wish to connect to commercial or other databases which do not
+ support open standards, please contact Index Data. We have a licensing
+ agreement with a third party vendor which will enable pazpar2 to access
+ thousands of online databases, in addition the vast number of catalogs
+ and online services that support the Z39.50 protocol.
+ </para>
+ <para>
+ Pazpar2 is our attempt to re-think the traditional paradigms for
+ implementing and deploying metasearch logic, with an uncompromising
+ approach to performance, and attempting to make maximum use of the
+ capabilities of modern browsers. The demo user interface that
+ accompanies the distribution is but one example. If you think of new
+ ways of using pazpar2, we hope you'll share them with us, and if we
+ can provide assistance with regards to training, design, programming,
+ integration with different backends, hosting, or support, please don't
+ hesitate to contact us. If you'd like to see functionality in pazpar2
+ that is not there today, please don't hesitate to contact us. It may
+ already be in our development pipeline, or there might be a
+ possibility for you to help out by sponsoring development time or
+ code. Either way, get in touch and we will give you straight answers.
+ </para>
+ <para>
+ Enjoy!
+ </para>
+ <para>
+ Pazpar2 is covered by the GNU license version 2.
+ See <xref linkend="license"/> for further information.
</para>
</chapter>
- <chapter id="license">
- <title>pazpar2 License</title>
- <para>To be decided and written.</para>
- </chapter>
-
<chapter id="installation">
<title>Installation</title>
<para>
- pazpar2 depends on the following tools/libraries:
+ Pazpar2 depends on the following tools/libraries:
<variablelist>
<varlistentry><term><ulink url="&url.yaz;">YAZ</ulink></term>
<listitem>
</para>
</listitem>
</varlistentry>
+ <varlistentry><term><ulink url="&url.icu;">International
+ Components for Unicode (ICU)</ulink></term>
+ <listitem>
+ <para>
+ ICU provides Unicode support for non-english languages with
+ character sets outside the range of 7bit ASCII, like
+ Greek, Russian, German and Frensh. Pazpar2 uses the ICU
+ unicode character conversions, unicode normalization, case
+ folding and other fundamental operations needed in
+ tokenization, normalization and ranking of records.
+ </para>
+ <para>
+ Compiling, linking, and usage of the ICU libraries is optional,
+ but strongly recommended for usage in an international
+ environment.
+ </para>
+ </listitem>
+ </varlistentry>
</variablelist>
</para>
<para>
- In order to compile pazpar2 an ANSI C compiler is
+ In order to compile Pazpar2 an ANSI C compiler is
required. The requirements should be the same as for YAZ.
</para>
<title>Installation on Unix (from Source)</title>
<para>
Here is a quick step-by-step guide on how to compile the
- tools that pazpar2 uses. Only few systems have none of the required
+ tools that Pazpar2 uses. Only few systems have none of the required
tools binary packages. If, for example, Libxml2/libxslt are already
- installed as development packages use those (and omit compilation).
+ installed as development packages use these.
</para>
<para>
Ensure that the development libraries + header files are
- available on your system before compiling pazpar2. For installation
+ available on your system before compiling Pazpar2. For installation
of YAZ, refer to the YAZ installation chapter.
</para>
<screen>
<section id="installation.debian">
<title>Installation on Debian GNU/Linux</title>
<para>
- All dependencies for pazpar2 are available as
+ All dependencies for Pazpar2 are available as
<ulink url="&url.debian;">Debian</ulink>
packages for the sarge (stable in 2005) and etch (testing in 2005)
distributions.
</para>
<screen>
apt-get install libyaz-dev
+ apt-get install libicu36-dev
</screen>
<para>
With these packages installed, the usual configure + make
- procedure can be used for pazpar2 as outlined in
+ procedure can be used for Pazpar2 as outlined in
<xref linkend="installation.unix"/>.
</para>
</section>
- </chapter>
-
- <reference id="refguide">
- <title>Reference guide</title>
+
+ <section id="installation.apache2proxy">
+ <title>Apache 2 Proxy</title>
+ <para>
+ Apache 2 has a
+ <ulink url="http://httpd.apache.org/docs/2.2/mod/mod_proxy.html">
+ proxy module
+ </ulink> which allows Pazpar2 to become a backend to an Apache 2
+ based web service. The Apache 2 proxy must operate in the
+ <emphasis>Reverse</emphasis> Proxy mode.
+ </para>
+
+ <para>
+ On a Debian based Apache 2 system, the relevant modules can
+ be enabled with:
+ <screen>
+ sudo a2enmod proxy_http
+ </screen>
+ </para>
+
+ <para>
+ Traditionnally Pazpar2 interprets URL paths with suffix
+ <literal>/search.pz2</literal>.
+ The
+ <ulink
+ url="http://httpd.apache.org/docs/2.2/mod/mod_proxy.html#proxypass"
+ >ProxyPass</ulink> directive of Apache must be used to map a URL path
+ the the Pazpar2 server (listening port).
+ </para>
+
+ <note>
+ <para>
+ The ProxyPass directive takes a prefix rather than
+ a suffix as URL path. It is important that the Java Script code
+ uses the prefix given for it.
+ </para>
+ </note>
+
+ <example id="installation.apache2proxy.example">
+ <title>Apache 2 proxy configuration</title>
<para>
- The material in this chapter is drawn directly from the individual
- manual entries.
+ If Pazpar2 is running on port 9004 and the portal is using
+ <filename>search.pz2</filename> inside portal in directory
+ <filename>/myportal/</filename> we could use the following
+ Apache 2 configuration:
+
+ <screen><![CDATA[
+ <IfModule mod_proxy.c>
+ ProxyRequests Off
+
+ <Proxy *>
+ AddDefaultCharset off
+ Order deny,allow
+ Allow from all
+ </Proxy>
+
+ ProxyPass /myportal/search.pz2 http://localhost:9004/search.pz2
+ ProxyVia Off
+ </IfModule>
+ ]]></screen>
</para>
- &manref;
+ </example>
+ </section>
+
+ </chapter>
+
+ <chapter id="using">
+ <title>Using pazpar2</title>
+ <para>
+ This chapter provides a general introduction to the use and
+ deployment of pazpar2.
+ </para>
+
+ <section id="architecture">
+ <title>Pazpar2 and your systems architecture</title>
+ <para>
+ Pazpar2 is designed to provide asynchronous, behind-the-scenes
+ metasearching functionality to your application, exposing this
+ functionality using a simple webservice API that can be accessed
+ from any number of development environments. In particular, it is
+ possible to combine pazpar2 either with your server-side dynamic
+ website scripting, with scripting or code running in the browser, or
+ with any combination of the two. Pazpar2 is an excellent tool for
+ building advanced, Ajax-based user interfaces for metasearch
+ functionality, but it isn't a requirement -- you can choose to use
+ pazpar2 entirely as a backend to your regular server-side scripting.
+ When you do use pazpar2 in conjunction
+ with browser scripting (JavaScript/Ajax, Flash, applets,
+ etc.), there are special considerations.
+ </para>
+
+ <para>
+ Pazpar2 implements a simple but efficient HTTP server, and it is
+ designed to interact directly with scripting running in the browser
+ for the best possible performance, and to limit overhead when
+ several browser clients generate numerous webservice requests.
+ However, it is still desirable to use a conventional webserver,
+ such as Apache, to serve up graphics, HTML documents, and
+ server-side scripting. Because the security sandbox environment of
+ most browser-side programming environments only allows communication
+ with the server from which the enclosing HTML page or object
+ originated, pazpar2 is designed so that it can act as a transparent
+ proxy in front of an existing webserver (see <xref
+ linkend="pazpar2_conf"/> for details). In this mode, all regular
+ HTTP requests are transparently passed through to your webserver,
+ while pazpar2 only intercepts search-related webservice requests.
+ </para>
+
+ <para>
+ If you want to expose your combined service on port 80, you can
+ either run your regular webserver on a different port, a different
+ server, or a different IP address associated with the same server.
+ </para>
+
+ <para>
+ Sometimes, it may be necessary to implement functionality on your
+ regular webserver that makes use of search results, for example to
+ implement data import functionality, emailing results, history
+ lists, personal citation lists, interlibrary loan functionality
+ ,etc. Fortunately, it is simple to exchange information between
+ pazpar2, your browser scripting, and backend server-side scripting.
+ You can send a session ID and possibly a record ID from your browser
+ code to your server code, and from there use pazpar2s webservice API
+ to access result sets or individual records. You could even 'hide'
+ all of pazpar2s functionality between your own API implemented on
+ the server-side, and access that from the browser or elsewhere. The
+ possibilities are just about endless.
+ </para>
+ </section>
+
+ <section id="data_model">
+ <title>Your data model</title>
+ <para>
+ Pazpar2 does not have a preconceived model of what makes up a data
+ model. There are no assumption that records have specific fields or
+ that they are organized in any particular way. The only assumption
+ is that data comes packaged in a form that the software can work
+ with (presently, that means XML or MARC), and that you can provide
+ the necessary information to massage it into pazpar2's internal
+ record abstraction.
+ </para>
+
+ <para>
+ Handling retrieval records in pazpar2 is a two-step process. First,
+ you decide which data elements of the source record you are
+ interested in, and you specify any desired massaging or combining of
+ elements using an XSLT stylesheet (MARC records are automatically
+ normalized to MARCXML before this step). If desired, you can run
+ multiple XSLT stylesheets in series to accomplish this, but the
+ output of the last one should be a representation of the record in a
+ schema that pazpar2 understands.
+ </para>
+
+ <para>
+ The intermediate, internal representation of the record looks like
+ this:
+ <screen><![CDATA[
+ <record xmlns="http://www.indexdata.com/pazpar2/1.0"
+ mergekey="title The Shining author King, Stephen">
+
+ <metadata type="title">The Shining</metadata>
+
+ <metadata type="author">King, Stephen</metadata>
+
+ <metadata type="kind">ebook</metadata>
+
+ <!-- ... and so on -->
+ </record>
+ ]]></screen>
+
+ As you can see, there isn't much to it. There are really only a few
+ important elements to this file.
+ </para>
+
+ <para>
+ Elements should belong to the namespace
+ http://www.indexdata.com/pazpar2/1.0. If the root node contains the
+ attribute 'mergekey', then every record that generates the same
+ merge key (normalized for case differences, white space, and
+ truncation) will be joined into a cluster. In other words, you
+ decide how records are merged. If you don't include a merge key,
+ records are never merged. The 'metadata' elements provide the meat
+ of the elements -- the content. the 'type' attribute is used to
+ match each element against processing rules that determine what
+ happens to the data element next.
+ </para>
+
+ <para>
+ The next processing step is the extraction of metadata from the
+ intermediate representation of the record. This is governed by the
+ 'metadata' elements in the 'service' section of the configuration
+ file. See <xref linkend="config-server"/> for details. The metadata
+ in the retrieval record ultimately drives merging, sorting, ranking,
+ the extraction of browse facets, and display, all configurable.
+ </para>
+ </section>
+
+ <section id="client">
+ <title>Client development overview</title>
+ <para>
+ You can use pazpar2 from any environment that allows you to use
+ webservices. The initial goal of the software was to support
+ Ajax-based applications, but there literally are no limits to what
+ you can do. You can use pazpar2 from Javascript, Flash, Java, etc.,
+ on the browser side, and from any development environment on the
+ server side, and you can pass session tokens and record IDs freely
+ around between these environments to build sophisticated applications.
+ Use your imagination.
+ </para>
+
+ <para>
+ The webservice API of pazpar2 is described in detail in <xref
+ linkend="pazpar2_protocol"/>.
+ </para>
+
+ <para>
+ In brief, you use the 'init' command to create a session, a
+ temporary workspace which carries information about the current
+ search. You start a new search using the 'search' command. Once the
+ search has been started, you can follow its progress using the
+ 'stat', 'bytarget', 'termlist', or 'show' commands. Detailed records
+ can be fetched using the 'record' command.
+ </para>
+ </section>
+
+ <section id="nonstandard">
+ <title>Connecting to non-standard resources</title>
+ <para>
+ Pazpar2 uses Z39.50 as its switchboard language -- i.e. as far as it
+ is concerned, all resources speak Z39.50. It is, however, equipped
+ to handle a broad range of different server behavior, through
+ configurable query mapping and record normalization. If you develop
+ configuration, stylesheets, etc., for a new type of resources, we
+ encourage you to share your work. But you can also use pazpar2 to
+ connect to hundreds of resources that do not support standard
+ protocols.
+ </para>
+
+ <para>
+ For a growing number of resources, Z39.50 is all you need. Over the
+ last few years, a number of commercial, full-text resources have
+ implemented Z39.50. These can be used through pazpar2 with little or
+ no effort. Resources that use non-standard record formats will
+ require a bit of XSLT work, but that's all.
+ </para>
+
+ <para>
+ But what about resources that don't support Z39.50 at all? The NISO
+ SRU (MXG) protocol is slowly gathering steam. Other resources might
+ support OpenSearch, private, XML/HTTP-based protocols, or something
+ else entirely. Some databases exist only as web user interfaces and
+ will require screen-scraping. Still others exist only as static
+ files, or perhaps as databases supporting the OAI-PMH protocol.
+ There is hope! Read on.
+ </para>
+
+ <para>
+ Index Data continues to advocate the support of open standards. We
+ work with database vendors to support standards, so you don't have
+ to worry about programming against non-standard services. We also
+ provide tools (see <ulink
+ url="http://www.indexdata.com/simpleserver">SimpleServer</ulink>)
+ which make it comparatively easy to build gateways against servers
+ with non-standard behavior. Again, we encourage you to share any
+ work you do in this direction.
+ </para>
+
+ <para>
+ But the bottom line is that working with non-standard resources in
+ metasearching is really, really hard. If you want to build a
+ project with pazpar2, and you need access to resources with
+ non-standard interfaces, we can help. We run gateways to more than
+ 2,000 popular, commercial databases and other resources,
+ making it simple
+ to plug them directly into pazpar2. For a small annual fee per
+ database, we can help you establish connections to your licensed
+ resources. Meanwhile, you can help! If you build your own
+ standards-compliant gateways, host them for others, or share the
+ code! And tell your vendors that they can save everybody money and
+ increase the appeal of their resources by supporting standards.
+ </para>
+
+ <para>
+ There are those who will ask us why we are using Z39.50 as our
+ switchboard langyage rather than a different protocol. Basically,
+ we believe that Z39.50 is presently the most widely implemented
+ information retrieval protocol that has the level of functionality
+ required to support a good metasearching experience (structured
+ searching, structured, well-defined results). It is also compact and
+ efficient, and there is a very broad range of tools available to
+ implement it.
+ </para>
+ </section>
+
+ <section id="unicode">
+ <title>Unicode Compliance</title>
+ <para>
+ Pazpar2 is unicode compliant and language and locale aware to
+ the exted the used backend Z39.50 targets are. Just a few bad
+ behaving targets can spoil the search experience considerably
+ if for example Greek, Russian or otherwise non 7-bit ASCII
+ search terms are entered. In these cases some targets return
+ records irrelevant to the query, and the result screens wil be
+ cluttered with noise.
+ </para>
+ <para>
+ While noise from misbehaving targets can not be removed, it can
+ be reduced using truely unicode based ranking. This is an
+ option which is available to the system administrator if ICU
+ support is compiled into Pazpar2, see
+ <xref linkend="installation"/> for details.
+ </para>
+ <para>
+ In addition, the ICU tokenization and normalization rules must
+ be defined in the master configuration file described in
+ <xref linkend="config-server"/>.
+ </para>
+ </section>
+
+ </chapter> <!-- Using pazpar2 -->
+
+ <reference id="reference">
+ <title>Reference</title>
+ <partintro id="reference-introduction">
+ <para>
+ The material in this chapter is drawn directly from the individual
+ manual entries.
+ </para>
+ </partintro>
+ &manref;
</reference>
+
+ <appendix id="license"><title>License</title>
+
+ <section id="gpl"><title>GPL</title>
+
+ <para>
+ Pazpar2,
+ Copyright © ©right-year; Index Data.
+ </para>
+
+ <para>
+ Pazpar2 is free software; you can redistribute it and/or modify it under
+ the terms of the GNU General Public License as published by the Free
+ Software Foundation; either version 2, or (at your option) any later
+ version.
+ </para>
+
+ <para>
+ Pazpar2 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 General Public License
+ for more details.
+ </para>
+
+ <para>
+ You should have received a copy of the GNU General Public License
+ along with Pazpar2; see the file LICENSE. If not, write to the
+ Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA
+ 02111-1307, USA.
+ </para>
+
+ <screen>
+ 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 License instead.) You can apply it to
+your programs, 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 software, or if you modify it.
+
+ For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must give the recipients all the rights that
+you have. You must make sure that they, too, receive or can get the
+source code. And you must show them these terms so they know their
+rights.
+
+ We protect your rights with two steps: (1) copyright the software, and
+(2) offer you this license which gives you legal permission to copy,
+distribute and/or modify the software.
+
+ Also, for each author's protection and ours, we want to make certain
+that everyone understands that there is no warranty for this free
+software. If the software is modified by someone else and passed on, we
+want its recipients to know that what they have is not the original, 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 redistributors of a free
+program will individually obtain patent licenses, in effect making the
+program proprietary. To prevent this, we have made it clear that any
+patent must be licensed for everyone's free use or not licensed at all.
+
+ The precise terms and conditions for copying, distribution and
+modification follow.
+
+ GNU GENERAL PUBLIC LICENSE
+ 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 of this General Public License. The "Program", below,
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+that is to say, a work 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 by this License; they are outside its scope. The act of
+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
+Program (independent of having been 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 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 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
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+
+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 License will not have their licenses terminated so long as such
+parties remain in full compliance.
+
+ 5. 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 Program or its derivative works. These actions are
+prohibited by law if you do not accept this License. Therefore, by
+modifying or distributing the Program (or any work based on the
+Program), you indicate your acceptance of this License to do so, and
+all its terms and conditions for copying, distributing or modifying
+the Program or works based on it.
+
+ 6. Each time you redistribute the Program (or any work based on the
+Program), the recipient automatically receives a license from the
+original licensor to copy, distribute or modify the Program 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.
+
+ 7. 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 Program at all. For example, if a patent
+license would not permit royalty-free redistribution of the Program 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 Program.
+
+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
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+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.
+
+ 8. If the distribution and/or use of the Program is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Program 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.
+
+ 9. The Free Software Foundation may publish revised and/or new versions
+of the 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 Program
+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 Program does not specify a version number of
+this License, you may choose any version ever published by the Free Software
+Foundation.
+
+ 10. If you wish to incorporate parts of the Program into other free
+programs whose distribution conditions are different, 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
+
+ 11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, THERE IS NO WARRANTY
+FOR THE PROGRAM, TO THE EXTENT PERMITTED BY APPLICABLE LAW. EXCEPT WHEN
+OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR OTHER PARTIES
+PROVIDE THE PROGRAM "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 PROGRAM IS WITH YOU. SHOULD THE
+PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING,
+REPAIR OR CORRECTION.
+
+ 12. 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 PROGRAM 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 PROGRAM (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 PROGRAM TO OPERATE WITH ANY OTHER
+PROGRAMS), EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGES.
+
+ END OF TERMS AND CONDITIONS
+ </screen>
+ </section>
+ </appendix>
+
</book>
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