-<!-- $Id: zoom.xml,v 1.1 2001-10-23 21:00:19 adam Exp $ -->
- <chapter><title>ZOOM</title>
+<!-- $Id: zoom.xml,v 1.2 2001-10-24 09:27:59 adam Exp $ -->
+ <chapter id="zoom"><title>ZOOM</title>
<para>
&zoom; is an acronym for Z39.50 Object Oriented Model and is
that because of typedefs. All destroy methods should gracefully ignore a
<literal>NULL</literal> pointer.
</para>
- <sect1><title>Connections</title>
+ <sect1 id="zoom.connections"><title>Connections</title>
- <para>The connection object Z3950_connection describes
- the connection between your client and a server.
+ <para>The Connection object is a session with a target.
</para>
<synopsis>
#include <yaz/zoom.h>
const char *Z3950_connection_option (Z3950_connection c,
const char *key,
const char *val);
+ const char *Z3950_connection_host (Z3950_connection c);
</synopsis>
<para>
The <function>Z3950_connection_option</function> allows you to
the option is unchanged.
The function returns the previous value of the option.
</para>
- <synopsis>
- const char *Z3950_connection_host (Z3950_connection c);
-
- </synopsis>
+ <table frame="top"><title>ZOOM Connection Options</title>
+ <tgroup cols="3">
+ <colspec colwidth="4*" colname="name"></colspec>
+ <colspec colwidth="7*" colname="description"></colspec>
+ <colspec colwidth="3*" colname="default"></colspec>
+ <thead>
+ <row>
+ <entry>Option</entry>
+ <entry>Description</entry>
+ <entry>Default</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row><entry>
+ implementationName</entry><entry>Name of Your client
+ </entry><entry>none</entry></row>
+ <row><entry>
+ user</entry><entry>Authentication user name
+ </entry><entry>none</entry></row>
+ <row><entry>
+ group</entry><entry>Authentication group name
+ </entry><entry>none</entry></row>
+ <row><entry>
+ pass</entry><entry>Authentication password
+ </entry><entry>none</entry></row>
+ <row><entry>
+ proxy</entry><entry>Proxy host
+ </entry><entry>none</entry></row>
+ <row><entry>
+ async</entry><entry>If true (1) the connection operates in
+ asynchronous operatio which means that all calls are non-blocking
+ except <function>Z3950_event</function>.
+ </entry><entry>0</entry></row>
+ <row><entry>
+ maximumRecordSize</entry><entry> Maximum size of single record.
+ </entry><entry>1 MB</entry></row>
+ <row><entry>
+ preferredMessageSize</entry><entry> Maximum size of multiple records.
+ </entry><entry>1 MB</entry></row>
+ </tbody>
+ </tgroup>
+ </table>
<para>
Function <function>Z3950_connection_host</function> returns
- the host for the connection as specified in either a call to
+ the host for the connection as specified in a call to
<function>Z3950_connection_new</function> or
<function>Z3950_connection_connect</function>.
This function returns <literal>NULL</literal> if host isn't
non-<literal>NULL</literal>.
</para>
</sect1>
- <sect1><title>Search objects</title>
+ <sect1 id="zoom.search"><title>Search objects</title>
<para>
Search objects defines how result sets are obtained. They
act like queries.
<para>
Create search objects using <function>Z3950_search_create</function>
and destroy them by calling <function>Z3950_search_destroy</function>.
- RPN-queries can be specified in PQF notation by using the
+ RPN-queries can be specified in <link linkend="PQF">PQF</link>
+ notation by using the
function <function>Z3950_search_prefix</function>. More
- query types will be added later, such as CCL to RPN-mapping, CCL
- query, etc.
- In addition to a search a sort critieria may be set. Function
- <function>Z3950_search_sortby</function> specifies a sort
- criteria using the same string notation for sort as offered by
- the YAZ client.
+ query types will be added later, such as
+ <link linkend="CCL">CCL</link> to RPN-mapping, native CCL query,
+ etc. In addition to a search, a sort critieria may be set. Function
+ <function>Z3950_search_sortby</function> specifies a
+ sort criteria using the same string notation for sort as offered by
+ the <link linkend="sortspec">YAZ client</link>.
</para>
</sect1>
- <sect1><title>Result sets</title>
+ <sect1 id="zoom.resultsets"><title>Result sets</title>
<para>
- The result set describes a collection of records obtained from
+ The result set object is a container for records returned from
+ a target.
search.
</para>
<synopsis>
a result set given a connection - and search object.
Destroy a result set by calling
<function>Z3950_resultset_destroy</function>.
- Simple clients using YAZ' prefix query format may use
- function <function>Z3950_connection_search_pqf</function>
- instead.
+ Simple clients using PQF only may use function
+ <function>Z3950_connection_search_pqf</function> instead.
</para>
<synopsis>
const char *Z3950_resultset_option (Z3950_resultset r,
void *Z3950_resultset_get (Z3950_resultset s, int pos,
const char *type, int *len);
- void Z3950_resultset_records (Z3950_resultset r,
- Z3950_record *recs,
- size_t *cnt);
</synopsis>
<para>
- Description of result sets here.
+ Function <function>X3950_resultset_options</function> sets or
+ modifies an option for a result set similar to
+ <function>Z3950_connection_option</function>.
</para>
+ <para>
+ The number of hits also called result-set is returned by
+ function <function>3950_resultset_size</function>.
+ </para>
+ <para>
+ Function <function>Z3950_resultset_get</function> is similar to
+ <link linkend="zoom.record.get">
+ <function>Z3950_record_get</function></link> but
+ instead of operating on a record object it operates on a record on
+ a given offset within a result set.
+ </para>
+ <table frame="top"><title>ZOOM Result set Options</title>
+ <tgroup cols="3">
+ <colspec colwidth="4*" colname="name"></colspec>
+ <colspec colwidth="7*" colname="description"></colspec>
+ <colspec colwidth="2*" colname="default"></colspec>
+ <thead>
+ <row>
+ <entry>Option</entry>
+ <entry>Description</entry>
+ <entry>Default</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row><entry>
+ piggyback</entry><entry>True (1) if piggyback should be
+ used in searches; false (0) if not.
+ </entry><entry>1</entry></row>
+ <row><entry>
+ start</entry><entry>Offset of first record we wish to
+ retrieve from the target. Note first record has offset 0
+ unlike the protocol specifications where first record has position
+ 1.
+ </entry><entry>0</entry></row>
+ <row><entry>
+ count</entry><entry>Number of records to be retrieved.
+ </entry><entry>0</entry></row>
+ <row><entry>
+ elementSetName</entry><entry>Element-Set name of records.
+ Most targets should honor element set name <literal>B</literal>
+ and <literal>F</literal> for brief and full respectively.
+ </entry><entry>none</entry></row>
+ <row><entry>
+ preferredRecordSyntax</entry><entry>Preferred Syntax, like
+ <literal>USMARC</literal>, <literal>SUTRS</literal>, etc.
+ </entry><entry>none</entry></row>
+ <row><entry>
+ databaseName</entry><entry>One or more database names
+ separated by character plus (<literal>+</literal>).
+ </entry><entry>Default</entry></row>
+ </tbody>
+ </tgroup>
+ </table>
</sect1>
- <sect1><title>Records</title>
+ <sect1 id="zoom.records"><title>Records</title>
<para>
A record object is a retrival record on the client side -
created from result sets.
</para>
<synopsis>
+ void Z3950_resultset_records (Z3950_resultset r,
+ Z3950_record *recs,
+ size_t *cnt);
Z3950_record Z3950_resultset_record (Z3950_resultset s, int pos);
- Z3950_record Z3950_resultset_record_immediate (Z3950_resultset s,
- int pos);
-
void *Z3950_record_get (Z3950_record rec, const char *type,
int *len);
void Z3950_record_destroy (Z3950_record rec);
</synopsis>
+ <para>
+ Records are created by functions
+ <function>Z3950_resultset_records</function> or
+ <function>Z3950_resultset_record</function>
+ and destroyed by <function>Z3950_resultset_destroy</function>.
+ </para>
+ <para>
+ A single record is created and returned by function
+ <function>Z3950_resultset_record</function> that takes a
+ position as argument. First record has position zero.
+ If no record could be obtained <literal>NULL</literal>.
+ </para>
+ <para>
+ Function <function>Z39_resultset_records</function>retrieves
+ a number of records from a result set. Options <literal>start</literal>
+ and <literal>count</literal> specifies the range of records to
+ be returned. Upon completion <literal>recs[0], ..recs[*cnt]</literal>
+ holds record objects for the records. These array of records
+ <literal>recs</literal> should be allocate prior to calling
+ <function>Z3950_resultset_records</function>. Note that for
+ records that couldn't be retrieved from the target
+ <literal>recs[ ..]</literal> is <literal>NULL</literal>.
+ </para>
+ <para id="zoom.record.get">
+ In order to extract information about a single record,
+ <function>Z3950_record_get</function> is provided. The
+ function returns a pointer to certain record information. The
+ nature (type) of the pointer depends on the <function>type</function>
+ given. In addition for certain types, the length
+ <literal>len</literal> passed will be set to the size in bytes of
+ the returned information. The types <literal>database</literal>,
+ <literal>syntax</literal> and <literal>render</literal> are
+ supported. More will be added later.
+ </para>
</sect1>
- <sect1><title>Options</title>
+ <sect1 id="zoom.options"><title>Options</title>
<para>
Most objects in &zoom; allows you to specify options to change
behaviour. From an implementation point of view a set of options
void *handle);
</synopsis>
</sect1>
- <sect1><title>Events</title>
+ <sect1 id="zoom.events"><title>Events</title>
<para>
If you're developing non-blocking applications you have to deal
with events.
<synopsis>
int Z3950_event (int no, Z3950_connection *cs);
</synopsis>
+ <para>
+ The <function>Z3950_event</function> executes pending events for
+ a number of connections. Supply the number of connections in
+ <literal>no</literal> and an array of connections in
+ <literal>cs</literal> (<literal>cs[0] ... cs[no-1]</literal>).
+ A pending event could be a sending a search, receiving a response,
+ etc.
+ When an event has a occured for one of the connections this function
+ returns a positive integer <literal>n</literal> denoting that an event
+ occurred for connection <literal>cs[n-1]</literal>.
+ When no events are pending for the connections a value of zero is
+ returned.
+ To make sure all outstanding requests are performed call is function
+ repeatedly until zero is returned.
+ </para>
</sect1>
</chapter>
projects / yaz-moved-to-github.git / blobdiff