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--- en:user_advanced:z3950 [2014/04/13 23:52] – external edit 127.0.0.1
+++ en:user_advanced:z3950 [2020/11/11 23:12] – kjdon
@@ Line 2: / Line 2: @@
 **[[http://www.loc.gov/z3950/agency/|Z39.50]]** is an international client/server protocol for searching bibliographic data. It can use the Internet Protocol (TCP/IP), which makes the databases on a server available from almost anywhere around the globe. It is widely used, for example, in on-line library catalogues. It allows a user to search one or more databases and retrieve the results of the query.
-Greenstone has support for Z39.50, both as a client and a server. GLI can download MARC records using Z39.50 and MARCXML records using SRU. These records can then be included in a collection. This support is enabled by default.
+Greenstone has support for Z39.50, both as a client (Greenstone 2 and 3) and a server (Greenstone 2). GLI can download MARC records using Z39.50 and MARCXML records using SRU. These records can then be included in a collection. This support is enabled by default.
-The Greenstone run-time can also act as a client to multiple Z39.50 servers, and a Z39.50 server program is also available.  This support is not enabled by default, and recompilation is needed to enable it. To do this, you need the source code. If you don't already have the source, download the version of the source code component that matches the distribution you are using.
+The Greenstone 2 run-time can also act as a client to multiple Z39.50 servers, and a Z39.50 server program is also available.  This support is not enabled by default, and recompilation is needed to enable it. To do this, you need the source code. If you don't already have the source, download the version of the source code component that matches the distribution you are using.
-Z39.50 support in Greenstone is based around the YAZ toolkit, written by [[http://www.indexdata.dk/|IndexData]]. We are currently using YAZ version 2.1.4. This is included in the Greenstone distribution without modification. Greenstone links against the ''libyaz.a'' library. We have also written ''yaz_zclient.h/cpp'', which is based on the sample ''client.h/cpp''. This is found in //greenstone/runtime-src/src/z3950//.
+Z39.50 support in Greenstone is based around the YAZ toolkit, written by [[http://www.indexdata.dk/|IndexData]]. We are currently using YAZ version 2.1.4. This is included in the Greenstone 2 distribution without modification. Greenstone links against the ''libyaz.a'' library. We have also written ''yaz_zclient.h/cpp'', which is based on the sample ''client.h/cpp''. This is found in //greenstone/runtime-src/src/z3950//.
 ===== Download through Z39.50 =====
@@ Line 14: / Line 14: @@
 ^Argument^Description^
-|Host (''-host'')|(REQUIRED) name of the Z39.50 server, for example //z3950.loc.gov//|
+|Host (''-host'')|(REQUIRED) name of the Z39.50 server, for example // lx2.loc.gov//|
-|Port (''-port'')|(REQUIRED) port number of the server, for example //7090//|
+|Port (''-port'')|(REQUIRED) port number of the server, for example //210//|
-|Database (''-database'')|(REQUIRED) name of the database to which the query will be sent|
+|Database (''-database'')|(REQUIRED) name of the database to which the query will be sent, for example // LCDB_MARC8//|
 |Find (''-find'')| (REQUIRED) query (//[[#querying in YAZ|see below]]//)|
 |Max records (''-max_records'')|Select to limit the size of result set; Default: 500|
@@ Line 144: / Line 144: @@
   * **The Z39.50 client will not work when fast-cgi is used**. Currently, the use of the fast-cgi package (off by default) will disable the use of the Z39.50 client code for Greenstone.
   * When viewing a Z39.50 "collection" in Greenstone, sometimes the browser may insert a large amount of space between the collection title and the navigation bar. Reload or Shift Reload should fix this problem.
+===== About z39.50 =====
+Sometimes, the best explanation is the simplest one. Z39.50 is a network protocol that provides
+access to information systems.
+Z39.50 was originally developed to meet the needs of libraries to integrate their online catalog
+systems. It has since been adopted by various other domains, and it remains arguably the most
+flexible, versatile and efficient information retrieval around. It is also open; the specification
+can be downloaded freely from the net.
+It has been considered complex by some, but its flexibility is mostly derived from the fact that it
+is a fairly complete model of the task if information retrieval -- and from that follows a certain
+measure of complexity.
+We still consider Z39.50 to be an important building block in the construction of information
+architectures, and much of our work in the past has been about maximising the usefulness and
+minimising the complexity of Z39.50 by providing well-designed toolkits for programmers wishing to
+implement the protocol. You'll find much more information about our tools under the software page.
+===== About YAZ =====
+YAZ stands for Yet Another Z39.50 toolkit.
+YAZ is a compact toolkit that provides access to the Z39.50 and SRW/SRU protocols, as well as a
+set of higher-level tools for implementing the server and client roles, respectively. The documentation
+can be used on its own, or as a reference when looking at the example applications provided with
+the package.
+=== How to make apps using YAZ on UNIX ===
+http://www.indexdata.dk/yaz/doc/installation.unix.tkl#id2528482
+This section describes how to compile - and link your own applications using the YAZ toolkit.
+If you're used to Makefiles this shouldn't be hard. As for other libraries you have used before,
+you have to set a proper include path for your C/C++ compiler and specify the location of YAZ
+libraries. You can do it by hand, but generally we suggest you use the yaz-config that is generated
+by configure. This is especially important if you're using the threaded version of YAZ which requires
+you to pass more options to your linker/compiler.
+The yaz-config script accepts command line options that makes the yaz-config script print options that
+you should use in your make process. The most important ones are: --cflags, --libs which prints C compiler
+flags, and linker flags respectively.
+A small and complete Makefile for a C application consisting of one source file, myprog.c, may look
+like this:
+ YAZCONFIG=/usr/local/bin/yaz-config
+ CFLAGS=`$(YAZCONFIG) --cflags`
+ LIBS=`$(YAZCONFIG) --libs`
+ myprog: myprog.o
+ $ (CC) $(CFLAGS) -o myprog myprog.o $(LIBS)
+The CFLAGS variable consists of a C compiler directive that will set the include path to the parent
+directory of yaz. That is, if YAZ header files were installed in /usr/local/include/yaz, then include
+path is set to /usr/local/include. Therefore, in your applications you should use
+ # include <yaz/proto.h>
+ and not
+ # include <proto.h>
+For Libtool users, the yaz-config script provides a different variant of option --libs, called
+--lalibs that returns the name of the Libtool acrhive(s) for YAZ rather than the ordinary ones.
+For applications using the threaded version of YAZ, specify threads after the other options. When
+threads is given, more flags and linker flags will be printed by yaz-config. If our previous example
+was using threads, you'd have to modify the lines that set CFLAGS and LIBS as follows:
+ CFLAGS=`$(YAZCONFIG) --cflags threads`
+ LIBS=`$(YAZCONFIG) --libs threads`
+There is no need specify POSIX thread libraries in your Makefile. The LIBS variable includes that
+as well.