X-Git-Url: http://jsfdemo.indexdata.com/?a=blobdiff_plain;f=doc%2Fbook.xml;h=6de2bad3913d093313ad14fadb48ec85b55c705d;hb=637a685d61a9ff0e3f398a59da426979815c4d68;hp=2c96f95adde4494940bfd45db370b4f60c4d871e;hpb=3953421488cf82acb6553f51a049e82892c0277a;p=metaproxy-moved-to-github.git diff --git a/doc/book.xml b/doc/book.xml index 2c96f95..6de2bad 100644 --- a/doc/book.xml +++ b/doc/book.xml @@ -2,7 +2,8 @@ + + %local; @@ -17,34 +18,43 @@ --> ]> - + Metaproxy - User's Guide and Reference - - AdamDickmeiss - - - MarcCromme - - - MikeTaylor - + + + AdamDickmeiss + + + MarcCromme + + + MikeTaylor + + + &version; - 2006 + 2005-2007 Index Data ApS + This manual is part of Metaproxy version &version;. + + Metaproxy is a universal router, proxy and encapsulated metasearcher for information retrieval protocols. It accepts, processes, interprets and redirects requests from IR clients using - standard protocols such as + standard protocols such as the binary ANSI/NISO Z39.50 - (and in the future SRU - and SRW), as + and the information search and retireval + web services SRU + and SRW, as well as functioning as a limited HTTP server. + + Metaproxy is configured by an XML file which specifies how the software should function in terms of routes that the request packets can take through the proxy, each step on a @@ -55,10 +65,7 @@ using the filter API. - Metaproxy is not open-source software, but - may be freely downloaded, unpacked, inspected, built and run for - evaluation purposes. Deployment requires a separate, commercial, - license. + Metaproxy is covered by the GNU General Public License version 2. @@ -76,7 +83,6 @@ Introduction - Metaproxy is a stand alone program that acts as a universal router, proxy and @@ -127,60 +133,6 @@ including examples. - - - The Metaproxy License - - - - You are allowed to download this software for evaluation purposes. - You can unpack it, build it, run it, see how it works and how it fits - your needs, all at zero cost. - - - - - You may NOT deploy the software. For the purposes of this license, - deployment means running it for any purpose other than evaluation, - whether or not you or anyone else makes a profit from doing so. If - you wish to deploy the software, you must first contact Index Data and - arrange to purchase a DEPLOYMENT LICENCE. If you are unsure - whether or not your proposed use of the software constitutes - deployment, email us at info@indexdata.com - for clarification. - - - - - You may modify your copy of the software (fix bugs, add features) - if you need to. We encourage you to send your changes back to us for - integration into the master copy, but you are not obliged to do so. You - may NOT pass your changes on to any other party. - - - - - There is NO WARRANTY for this software, to the extent permitted by - applicable law. We provide the software ``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 software is with you. Should the software prove - defective, you assume the cost of all necessary servicing, repair or - correction. In no event unless required by applicable law will we be - liable to you for damages, arising out of the use of the software, - including but not limited to loss of data or data being rendered - inaccurate. - - - - - All rights to the software are reserved by Index Data except where - this license explicitly says otherwise. - - - - Installation @@ -333,6 +285,39 @@ +
+ Installation on RPM based Linux Systems + + All external dependencies for Metaproxy are available as + RPM packages, either from your distribution site, or from the + RPMfind site. + + + For example, an installation of the requires Boost C++ development + libraries on RedHat Fedora C4 and C5 can be done like this: + + wget ftp://fr.rpmfind.net/wlinux/fedora/core/updates/testing/4/SRPMS/boost-1.33.0-3.fc4.src.rpm + sudo rpmbuild --buildroot src/ --rebuild -p fc4/boost-1.33.0-3.fc4.src.rpm + sudo rpm -U /usr/src/redhat/RPMS/i386/boost-*rpm + + + + The YAZ library is needed to + compile &metaproxy;, see there + for more information on available RPM packages. + + + There is currently no official RPM package for YAZ++. + See the YAZ++ pages + for more information on a Unix tarball install. + + + With these packages installed, the usual configure + make + procedure can be used for Metaproxy as outlined in + . + +
+
Installation on Windows @@ -492,6 +477,152 @@
+ + YAZ Proxy Comparison + + The table below lists facilities either supported by either + YAZ Proxy or Metaproxy. + + + Metaproxy / YAZ Proxy comparison + + + + Facility + Metaproxy + YAZ Proxy + + + + + Z39.50 server + Using filter frontend_net + Supported + + + SRU server + Supported with filter sru_z3950 + Supported + + + Z39.50 client + Supported with filter z3950_client + Supported + + + SRU client + Unsupported + Unsupported + + + Connection reuse + Supported with filter session_shared + Supported + + + Connection share + Supported with filter session_shared + Unsupported + + + Result set reuse + Supported with filter session_shared + Within one Z39.50 session / HTTP keep-alive + + + Record cache + Unsupported + Supported for last result set within one Z39.50/HTTP-keep alive session + + + Z39.50 Virtual database, i.e. select any Z39.50 target for database + Supported with filter virt_db + Unsupported + + + SRU Virtual database, i.e. select any Z39.50 target for path + Supported with filter virt_db, + sru_z3950 + Supported + + + Multi target search + Supported with filter multi (round-robin) + Unsupported + + + Retrieval and search limits + Unsupported + Supported + + + Bandwidth limits + Unsupported + Supported + + + Connect limits + Unsupported + Supported + + + Retrieval sanity check and conversions + Supported using filter record_transform + Supported + + + Query check + + Supported in a limited way using query_rewrite + + Supported + + + Query rewrite + Supported with query_rewrite + Unsupported + + + Session invalidate for -1 hits + Unsupported + Supported + + + Architecture + Multi-threaded + select for networked modules such as + frontend_net) + Single-threaded using select + + + + Extensability + Most functionality implemented as loadable modules + Unsupported and experimental + + + + USEMARCON + Unsupported + Supported + + + + Portability + + Requires YAZ, YAZ++ and modern C++ compiler supporting + Boost. + + + Requires YAZ and YAZ++. + STL is not required so pretty much any C++ compiler out there should work. + + + + + +
+ + The Metaproxy Architecture @@ -572,7 +703,7 @@ plugins that provide new filters. The filter API is small and conceptually simple, but there are many details to master. See the section below on - extensions. + Filters. @@ -592,7 +723,7 @@ Filters -
+
Introductory notes It's useful to think of Metaproxy as an interpreter providing a small @@ -627,10 +758,10 @@ packages (frontend_net); others are sinks: they consume packages and return a result - (z3950_client, - backend_test, + (backend_test, bounce, - http_file); + http_file, + z3950_client); the others are true filters, that read, process and pass on the packages they are fed (auth_simple, @@ -653,8 +784,7 @@ the core Metaproxy binary. This overview is intended to give a flavor of the available functionality; more detailed information about each type of filter is included below in - the reference guide to Metaproxy filters. + . The filters are here named by the string that is used as the @@ -692,7 +822,7 @@ Figure out what additional information we need in: --> -
+
<literal>auth_simple</literal> (mp::filter::AuthSimple) @@ -711,7 +841,7 @@ Figure out what additional information we need in:
-
+
<literal>backend_test</literal> (mp::filter::Backend_test) @@ -722,7 +852,7 @@ Figure out what additional information we need in:
-
+
<literal>bounce</literal> (mp::filter::Bounce) @@ -732,15 +862,28 @@ Figure out what additional information we need in: sets Z39.50 packages to Z_Close, and HTTP_Request packages to HTTP_Response err code 400 packages, and adds a suitable bounce message. - The bounce filter is usually added at end of each filter chain - config.xml to prevent infinite hanging of for example HTTP + The bounce filter is usually added at end of each filter chain route + to prevent infinite hanging of for example HTTP requests packages when only the Z39.50 client partial sink filter is found in the route.
-
+
+ <literal>cql_rpn</literal> + (mp::filter::CQLtoRPN) + + A query language transforming filter which catches Z39.50 + searchRequest + packages containing CQL queries, transforms + those to RPN queries, + and sends the searchRequests on to the next + filters. It is among other things useful in a SRU context. + +
+ +
<literal>frontend_net</literal> (mp::filter::FrontendNet) @@ -751,11 +894,12 @@ Figure out what additional information we need in:
-
+
<literal>http_file</literal> (mp::filter::HttpFile) - A partial sink which swallows only HTTP_Request packages, and + A partial sink which swallows only + HTTP_Request packages, and returns the contents of files from the local filesystem in response to HTTP requests. It lets Z39.50 packages and all other forthcoming package types @@ -767,7 +911,27 @@ Figure out what additional information we need in:
-
+
+ <literal>load_balance</literal> + (mp::filter::LoadBalance) + + Performs load balancing for incoming Z39.50 init requests. + It is used together with the virt_db filter, + but unlike the multi filter it does send an + entire session to only one of the virtual backends. The + load_balance filter is assuming that + all backend targets have equal content, and chooses the backend + with least load cost for a new session. + + + This filter is experimental and yet not mature for heavy load + production sites. + + + +
+ +
<literal>log</literal> (mp::filter::Log) @@ -776,8 +940,8 @@ Figure out what additional information we need in: as multiple different logging formats.
- -
+ +
<literal>multi</literal> (mp::filter::Multi) @@ -788,11 +952,13 @@ Figure out what additional information we need in:
-
+
<literal>query_rewrite</literal> (mp::filter::QueryRewrite) - Rewrites Z39.50 Type-1 and Type-101 (``RPN'') queries by a + Rewrites Z39.50 Type-1 + and Type-101 (``RPN'') + queries by a three-step process: the query is transliterated from Z39.50 packet structures into an XML representation; that XML representation is transformed by an XSLT stylesheet; and the @@ -802,7 +968,7 @@ Figure out what additional information we need in:
-
+
<literal>record_transform</literal> (mp::filter::RecordTransform) @@ -816,35 +982,40 @@ Figure out what additional information we need in:
-
+
<literal>session_shared</literal> (mp::filter::SessionShared) - When this is finished, it will implement global sharing of + This filter implements global sharing of result sets (i.e. between threads and therefore between - clients), yielding performance improvements especially when - incoming requests are from a stateless environment such as a - web-server, in which the client process representing a session - might be any one of many. However: + clients), yielding performance improvements by clever resource + pooling. - - - This filter is not yet completed. - -
-
+
<literal>sru_z3950</literal> (mp::filter::SRUtoZ3950) This filter transforms valid - SRU/GET or SRU/SOAP requests to Z3950 requests, and wraps the - received hit counts and XML records into suitable SRU response messages. + SRU GET/POST/SOAP searchRetrieve requests to Z3950 init, search, + and present requests, and wraps the + received hit counts and XML records into suitable SRU response + messages. + The sru_z3950 filter processes also SRU + GET/POST/SOAP explain requests, returning + either the absolute minimum required by the standard, or a full + pre-defined ZeeReX explain record. + See the + ZeeReX Explain + standard pages and the + SRU Explain pages + for more information on the correct explain syntax. + SRU scan requests are not supported yet.
-
+
<literal>template</literal> (mp::filter::Template) @@ -857,7 +1028,7 @@ Figure out what additional information we need in:
-
+
<literal>virt_db</literal> (mp::filter::VirtualDB) @@ -872,7 +1043,7 @@ Figure out what additional information we need in:
-
+
<literal>z3950_client</literal> (mp::filter::Z3950Client) @@ -888,6 +1059,29 @@ Figure out what additional information we need in: are passed untouched.
+ + +
+ <literal>zeerex_explain</literal> + (mp::filter::ZeerexExplain) + + This filter acts as a sink for + Z39.50 explain requests, returning a static ZeeReX + Explain XML record from the config section. All other packages + are passed through. + See the + ZeeReX Explain + standard pages + for more information on the correct explain syntax. + + + + This filter is not yet completed. + + +
+ +
@@ -910,34 +1104,10 @@ Figure out what additional information we need in: - frontend_sru (source) - - - Receive SRU (and perhaps SRW) requests. - - - - - sru2z3950 (filter) - - - Translate SRU requests into Z39.50 requests. - - - - sru_client (sink) - SRU searching and retrieval. - - - - - srw_client (sink) - - - SRW searching and retrieval. + SRU/GET and SRU/SOAP searching and retrieval. @@ -959,21 +1129,16 @@ Figure out what additional information we need in: Configuration: the Metaproxy configuration file format -
+
Introductory notes If Metaproxy is an interpreter providing operations on packages, then its configuration file can be thought of as a program for that - interpreter. Configuration is by means of a single file, the name + interpreter. Configuration is by means of a single XML file, the name of which is supplied as the sole command-line argument to the metaproxy program. (See - the reference guide - below for more information on invoking Metaproxy.) - - - The configuration files are written in XML. (But that's just an - implementation detail - they could just as well have been written - in YAML or Lisp-like S-expressions, or in a custom syntax.) + below for more information on invoking + Metaproxy.)
@@ -981,15 +1146,15 @@ Figure out what additional information we need in: Overview of the config file XML structure All elements and attributes are in the namespace - . + . This is most easily achieved by setting the default namespace on the top-level element, as here: - <yp2 xmlns="http://indexdata.dk/yp2/config/1"> + <metaproxy xmlns="http://indexdata.com/metaproxy" version="1.0"> - The top-level element is <yp2>. This contains a + The top-level element is <metaproxy>. This contains a <start> element, a <filters> element and a <routes> element, in that order. <filters> is optional; the other two are mandatory. All three are @@ -1009,7 +1174,7 @@ Figure out what additional information we need in: and contain various elements that provide suitable configuration for a filter of its type. The filter-specific elements are described in - the reference guide below. + . Filters defined in this part of the file must carry an id attribute so that they can be referenced from elsewhere. @@ -1045,7 +1210,7 @@ Figure out what additional information we need in: client-server dialogues. - + @@ -1062,7 +1227,7 @@ Figure out what additional information we need in: - + ]]> It works by defining a single route, called @@ -1093,7 +1258,26 @@ Figure out what additional information we need in: which returns the response to the client.
-
+ +
+ Config file modularity + + Metaproxy XML configuration snippets can be reused by other + filters using the XInclude standard, as seen in + the /etc/config-sru-to-z3950.xml example SRU + configuration. + + + + + +]]> + +
+ +
Config file syntax checking The distribution contains RelaxNG Compact and XML syntax checking @@ -1127,7 +1311,7 @@ Figure out what additional information we need in: Virtual databases and multi-database searching -
+
Introductory notes Two of Metaproxy's filters are concerned with multiple-database @@ -1186,7 +1370,7 @@ Figure out what additional information we need in: marc - indexdata.dk/marc + indexdata.com/marc ]]> @@ -1211,7 +1395,7 @@ Figure out what additional information we need in: Index Data's tiny testing database of MARC records: - + @@ -1226,12 +1410,12 @@ Figure out what additional information we need in: marc - indexdata.dk/marc + indexdata.com/marc all z3950.loc.gov:7090/voyager - indexdata.dk/marc + indexdata.com/marc @@ -1241,7 +1425,7 @@ Figure out what additional information we need in: -]]> +]]> (Using a virt_db @@ -1495,12 +1679,123 @@ Z> + + Combined SRU webservice and Z39.50 server configuration + + Metaproxy can act as + SRU and + SRW + web service server, which translates web service requests to + ANSI/NISO Z39.50 packages and + sends them off to common available targets. + + + A typical setup for this operation needs a filter route including the + following modules: + + + + SRU/Z39.50 Server Filter Route Configuration + + + + Filter + Importance + Purpose + + + + + + frontend_net + required + Accepting HTTP connections and passing them to following + filters. Since this filter also accepts Z39.50 connections, the + server works as SRU and Z39.50 server on the same port. + + + sru_z3950 + required + Accepting SRU GET/POST/SOAP explain and + searchRetrieve requests for the the configured databases. + Explain requests are directly served from the static XML configuration. + SearchRetrieve requests are + transformed to Z39.50 search and present packages. + All other HTTP and Z39.50 packages are passed unaltered. + + + http_file + optional + Serving HTTP requests from the filesystem. This is only + needed if the server should serve XSLT stylesheets, static HTML + files or Java Script for thin browser based clients. + Z39.50 packages are passed unaltered. + + + cql_rpn + required + Usually, Z39.50 servers do not talk CQL, hence the + translation of the CQL query language to RPN is mandatory in + most cases. Affects only Z39.50 search packages. + + + record_transform + optional + Some Z39.50 backend targets can not present XML record + syntaxes in common wanted element sets. using this filter, one + can transform binary MARC records to MARCXML records, and + further transform those to any needed XML schema/format by XSLT + transformations. Changes only Z39.50 present packages. + + + session_shared + optional + The stateless nature of web services requires frequent + re-searching of the same targets for display of paged result set + records. This might be an unacceptable burden for the accessed + backend Z39.50 targets, and this mosule can be added for + efficient backend target resource pooling. + + + z3950_client + required + Finally, a Z39.50 package sink is needed in the filter + chain to provide the response packages. The Z39.50 client module + is used to access external targets over the network, but any + coming local Z39.50 package sink could be used instead of. + + + bounce + required + Any Metaproxy package arriving here did not do so by + purpose, and is bounced back with connection closure. this + prevents inifinite package hanging inside the SRU server. + + + +
+ + A typical minimal example SRU and + SRW server configuration file is found + in the tarball distribution at + etc/config-sru-to-z3950.xml. + + + Off course, any other metaproxy modules can be integrated into a + SRU server solution, including, but not limited to, load balancing, + multiple target querying + (see ), and complex RPN query rewrites. + + + + + @@ -1508,12 +1803,12 @@ Z> Classes in the Metaproxy source code -
+
Introductory notes Stop! Do not read this! You won't enjoy it at all. You should just skip ahead to - the reference guide, + , which tells @@ -1554,7 +1849,7 @@ Z> parentheses. -
+
<literal>mp::FactoryFilter</literal> (<filename>factory_filter.cpp</filename>) @@ -1569,7 +1864,7 @@ Z>
-
+
<literal>mp::FactoryStatic</literal> (<filename>factory_static.cpp</filename>) @@ -1584,7 +1879,7 @@ Z>
-
+
<literal>mp::filter::Base</literal> (<filename>filter.cpp</filename>) @@ -1601,7 +1896,7 @@ Z>
-
+
<literal>mp::filter::AuthSimple</literal>, <literal>Backend_test</literal>, etc. (<filename>filter_auth_simple.cpp</filename>, @@ -1643,7 +1938,7 @@ Z> </itemizedlist> </section> - <section> + <section id="class-Package"> <title><literal>mp::Package</literal> (<filename>package.cpp</filename>) @@ -1654,7 +1949,7 @@ Z>
-
+
<literal>mp::Pipe</literal> (<filename>pipe.cpp</filename>) @@ -1664,7 +1959,7 @@ Z>
-
+
<literal>mp::RouterChain</literal> (<filename>router_chain.cpp</filename>) @@ -1672,7 +1967,7 @@ Z>
-
+
<literal>mp::RouterFleXML</literal> (<filename>router_flexml.cpp</filename>) @@ -1680,7 +1975,7 @@ Z>
-
+
<literal>mp::Session</literal> (<filename>session.cpp</filename>) @@ -1688,7 +1983,7 @@ Z>
-
+
<literal>mp::ThreadPoolSocketObserver</literal> (<filename>thread_pool_observer.cpp</filename>) @@ -1696,7 +1991,7 @@ Z>
-
+
<literal>mp::util</literal> (<filename>util.cpp</filename>) @@ -1707,7 +2002,7 @@ Z>
-
+
<literal>mp::xml</literal> (<filename>xmlutil.cpp</filename>) @@ -1762,9 +2057,9 @@ Z> - - - Reference guide + + Reference + The material in this chapter is drawn directly from the individual manual entries. In particular, the Metaproxy invocation section is @@ -1772,8 +2067,325 @@ Z> on each individual filter is available using the name of the filter as the argument to the man command. - &manref; + + &manref; + + + License + + + Metaproxy, Copyright © 1995-2007 Index Data ApS. + + + + Metaproxy 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. + + + + Metaproxy 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. + + + + You should have received a copy of the GNU General Public License + along with Metaproxy; see the file LICENSE. If not, write to the + Free Software Foundation, + 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + + + + GNU General Public License + + GNU GENERAL PUBLIC LICENSE + Version 2, June 1991 + + Copyright (C) 1989, 1991 Free Software Foundation, Inc. + 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA +w 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. 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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. 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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. + + 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 + + + +