3 ZOOM_connection_errcode(c)
4 ZOOM_connection_errmsg(c)
5 ZOOM_connection_addinfo(c)
6 ZOOM_connection_addinfo(c)
7 ZOOM_connection_diagset(c);
8 ZOOM_connection_save_apdu_wrbuf
10 ZOOM_resultset_record_immediate(s, pos)
11 ZOOM_resultset_cache_reset(r)
12 ZOOM_resultset_sort(r, sort_type, sort_spec)
13 ZOOM_resultset_sort1(r, sort_type, sort_spec)
14 ZOOM_options_set_callback(opt, function, handle)
15 ZOOM_options_create_with_parent2(parent1, parent2)
16 ZOOM_options_getl(opt, name, len)
17 ZOOM_options_setl(opt, name, value, len)
18 ZOOM_options_get_bool(opt, name, defa)
19 ZOOM_options_get_int(opt, name, defa)
20 ZOOM_options_set_int(opt, name, value)
21 ZOOM_query_cql2rpn(ZOOM_query s, const char *str, ZOOM_connection conn)
23 <chapter id="zoom"><title>ZOOM</title>
25 &zoom; is an acronym for 'Z39.50 Object-Orientation Model' and is
26 an initiative started by Mike Taylor (Mike is from the UK, which
27 explains the peculiar name of the model). The goal of &zoom; is to
28 provide a common Z39.50 client API not bound to a particular
29 programming language or toolkit.
33 From YAZ version 2.1.12, <ulink url="&url.sru;">SRU</ulink> is supported.
34 You can make SRU ZOOM connections by specifying scheme
35 <literal>http://</literal> for the hostname for a connection.
36 The dialect of SRU used is specified by the value of the
37 connection's <literal>sru</literal> option, which may be SRU over
38 HTTP GET (<literal>get</literal>),
39 SRU over HTTP POST (<literal>post</literal>), (SRU over
40 SOAP) (<literal>soap</literal>) or <literal>SOLR</literal>
41 (<ulink url="&url.solr;">SOLR</ulink> Web Service).
42 Using the facility for embedding options in target strings, a
43 connection can be forced to use SRU rather the SRW (the default) by
44 prefixing the target string with <literal>sru=get,</literal>, like this:
45 <literal>sru=get,http://sru.miketaylor.org.uk:80/sru.pl</literal>
48 <ulink url="&url.solr;">SOLR</ulink> protocol support was added to
49 YAZ in version 4.1.0, as a dialect of a SRU protocol, since both are
53 The lack of a simple Z39.50 client API for &yaz; has become more
54 and more apparent over time. So when the first &zoom; specification
56 an implementation for &yaz; was quickly developed. For the first time, it is
57 now as easy (or easier!) to develop clients than servers with &yaz;. This
58 chapter describes the &zoom; C binding. Before going further, please
59 reconsider whether C is the right programming language for the job.
60 There are other language bindings available for &yaz;, and still
62 are in active development. See the
63 <ulink url="&url.zoom;">ZOOM web-site</ulink> for
68 In order to fully understand this chapter you should read and
69 try the example programs <literal>zoomtst1.c</literal>,
70 <literal>zoomtst2.c</literal>, .. in the <literal>zoom</literal>
75 The C language misses features found in object oriented languages
76 such as C++, Java, etc. For example, you'll have to manually,
77 destroy all objects you create, even though you may think of them as
78 temporary. Most objects has a <literal>_create</literal> - and a
79 <literal>_destroy</literal> variant.
80 All objects are in fact pointers to internal stuff, but you don't see
81 that because of typedefs. All destroy methods should gracefully ignore a
82 <literal>NULL</literal> pointer.
85 In each of the sections below you'll find a sub section called
86 protocol behavior, that describes how the API maps to the Z39.50
89 <sect1 id="zoom-connections"><title>Connections</title>
91 <para>The Connection object is a session with a target.
94 #include <yaz/zoom.h>
96 ZOOM_connection ZOOM_connection_new(const char *host, int portnum);
98 ZOOM_connection ZOOM_connection_create(ZOOM_options options);
100 void ZOOM_connection_connect(ZOOM_connection c, const char *host,
102 void ZOOM_connection_destroy(ZOOM_connection c);
105 Connection objects are created with either function
106 <function>ZOOM_connection_new</function> or
107 <function>ZOOM_connection_create</function>.
108 The former creates and automatically attempts to establish a network
109 connection with the target. The latter doesn't establish
110 a connection immediately, thus allowing you to specify options
111 before establishing network connection using the function
112 <function>ZOOM_connection_connect</function>.
113 If the port number, <literal>portnum</literal>, is zero, the
114 <literal>host</literal> is consulted for a port specification.
115 If no port is given, 210 is used. A colon denotes the beginning of
116 a port number in the host string. If the host string includes a
117 slash, the following part specifies a database for the connection.
120 You can prefix the host with a scheme followed by colon. The
121 default scheme is <literal>tcp</literal> (Z39.50 protocol).
122 The scheme <literal>http</literal> selects SRU/get over HTTP by default,
123 but can overridded to use SRU/post, SRW and the SOLR protocol.
126 You can prefix the scheme-qualified host-string with one or more
128 <literal><parameter>key</parameter>=<parameter>value</parameter></literal>
129 sequences, each of which represents an option to be set into the
130 connection structure <emphasis>before</emphasis> the
131 protocol-level connection is forged and the initialization
132 handshake takes place. This facility can be used to provide
133 authentication credentials, as in host-strings such as:
134 <literal>user=admin,password=halfAm4n,tcp:localhost:8017/db</literal>
137 Connection objects should be destroyed using the function
138 <function>ZOOM_connection_destroy</function>.
141 void ZOOM_connection_option_set(ZOOM_connection c,
142 const char *key, const char *val);
144 void ZOOM_connection_option_setl(ZOOM_connection c,
146 const char *val, int len);
148 const char *ZOOM_connection_option_get(ZOOM_connection c,
150 const char *ZOOM_connection_option_getl(ZOOM_connection c,
155 The functions <function>ZOOM_connection_option_set</function> and
156 <function>ZOOM_connection_option_setl</function> allows you to
157 set an option given by <parameter>key</parameter> to the value
158 <parameter>value</parameter> for the connection.
159 For <function>ZOOM_connection_option_set</function>, the
160 value is assumed to be a 0-terminated string. Function
161 <function>ZOOM_connection_option_setl</function> specifies a
162 value of a certain size (len).
165 Functions <function>ZOOM_connection_option_get</function> and
166 <function>ZOOM_connection_option_getl</function> returns
167 the value for an option given by <parameter>key</parameter>.
169 <table id="zoom-connection-options" frame="top">
170 <title>ZOOM Connection Options</title>
172 <colspec colwidth="4*" colname="name"></colspec>
173 <colspec colwidth="7*" colname="description"></colspec>
174 <colspec colwidth="3*" colname="default"></colspec>
177 <entry>Option</entry>
178 <entry>Description</entry>
179 <entry>Default</entry>
184 implementationName</entry><entry>Name of Your client
185 </entry><entry>none</entry></row>
187 user</entry><entry>Authentication user name
188 </entry><entry>none</entry></row>
190 group</entry><entry>Authentication group name
191 </entry><entry>none</entry></row>
193 password</entry><entry>Authentication password.
194 </entry><entry>none</entry></row>
196 host</entry><entry>Target host. This setting is "read-only".
197 It's automatically set internally when connecting to a target.
198 </entry><entry>none</entry></row>
200 proxy</entry><entry>Proxy host. If set, the logical host
201 is encoded in the otherInfo area of the Z39.50 Init PDU
202 with OID 1.2.840.10003.10.1000.81.1.
203 </entry><entry>none</entry></row>
205 clientIP</entry><entry>Client IP. If set, is
206 encoded in the otherInfo area of a Z39.50 PDU with OID
207 1.2.840.10003.10.1000.81.3. Holds the original IP addreses
208 of a client. Is used of ZOOM is used in a gateway of some sort.
209 </entry><entry>none</entry></row>
211 async</entry><entry>If true (1) the connection operates in
212 asynchronous operation which means that all calls are non-blocking
214 <link linkend="zoom.events"><function>ZOOM_event</function></link>.
215 </entry><entry>0</entry></row>
217 maximumRecordSize</entry><entry> Maximum size of single record.
218 </entry><entry>1 MB</entry></row>
220 preferredMessageSize</entry><entry> Maximum size of multiple records.
221 </entry><entry>1 MB</entry></row>
223 lang</entry><entry> Language for negotiation.
224 </entry><entry>none</entry></row>
226 charset</entry><entry> Character set for negotiation.
227 </entry><entry>none</entry></row>
229 serverImplementationId</entry><entry>
230 Implementation ID of server. (The old targetImplementationId
231 option is also supported for the benefit of old applications.)
232 </entry><entry>none</entry></row>
234 targetImplementationName</entry><entry>
235 Implementation Name of server. (The old
236 targetImplementationName option is also supported for the
237 benefit of old applications.)
238 </entry><entry>none</entry></row>
240 serverImplementationVersion</entry><entry>
241 Implementation Version of server. (the old
242 targetImplementationVersion option is also supported for the
243 benefit of old applications.)
244 </entry><entry>none</entry></row>
246 databaseName</entry><entry>One or more database names
247 separated by character plus (<literal>+</literal>), which to
248 be used by subsequent search requests on this Connection.
249 </entry><entry>Default</entry></row>
251 piggyback</entry><entry>True (1) if piggyback should be
252 used in searches; false (0) if not.
253 </entry><entry>1</entry></row>
255 smallSetUpperBound</entry><entry>If hits is less than or equal to this
256 value, then target will return all records using small element set name
257 </entry><entry>0</entry></row>
259 largeSetLowerBound</entry><entry>If hits is greater than this
260 value, the target will return no records.
261 </entry><entry>1</entry></row>
263 mediumSetPresentNumber</entry><entry>This value represents
264 the number of records to be returned as part of a search when when
265 hits is less than or equal to large set lower bound and if hits
266 is greater than small set upper bound.
267 </entry><entry>0</entry></row>
269 smallSetElementSetName</entry><entry>
270 The element set name to be used for small result sets.
271 </entry><entry>none</entry></row>
273 mediumSetElementSetName</entry><entry>
274 The element set name to be for medium-sized result sets.
275 </entry><entry>none</entry></row>
277 init_opt_search, init_opt_present, init_opt_delSet, etc.</entry><entry>
278 After a successful Init, these options may be interrogated to
279 discover whether the server claims to support the specified
281 </entry><entry>none</entry></row>
283 <entry>sru</entry><entry>
284 SRU/SOLR transport type. Must be either <literal>soap</literal>,
285 <literal>get</literal>, <literal>post</literal>, or
286 <literal>solr</literal>.
287 </entry><entry>soap</entry></row>
289 sru_version</entry><entry>
290 SRU/SRW version. Should be <literal>1.1</literal>, or
291 <literal>1.2</literal>. This is , prior to connect, the version
292 to offer (highest version). And following connect (in fact
293 first operation), holds the negotiated version with the server
294 (same or lower version).
295 </entry><entry>1.2</entry></row>
297 facets</entry><entry>
298 A FacetList is comma-separated list of facet, which is defined
299 as <literal>AttributeList</literal> and a optional FacetTerm
300 (a Term and a frequency). On request the terms is missing.
301 On response the the list contains the terms that the target
303 </entry><entry>none</entry></row>
305 apdulog</entry><entry>
306 If set to a true value such as "1", a log of low-level
307 protocol packets is emitted on standard error stream. This
308 can be very useful for debugging.
309 </entry><entry>0</entry></row>
311 saveAPDU</entry><entry>
312 If set to a true value such as "1", a log of low-level
313 protocol packets is saved. The log can be retrieved by reading
314 option APDU. Setting saveAPDU always has the side effect of
315 resetting the currently saved log. This setting is
316 <emphasis>write-only</emphasis>. If read, NULL will be returned.
317 It is only recognized in
318 <function>ZOOM_connection_option_set</function>.
319 </entry><entry>0</entry></row>
322 Returns the log of protocol packets. Will be empty if logging
323 is not enabled (see saveAPDU above). This setting is
324 <emphasis>read-only</emphasis>. It is only recognized if used
325 in call to <function>ZOOM_connection_option_get</function> or
326 <function>ZOOM_connection_option_getl</function>.
327 </entry><entry></entry></row>
332 If either option <literal>lang</literal> or <literal>charset</literal>
334 <ulink url="&url.z39.50.charneg;">
335 Character Set and Language Negotiation</ulink> is in effect.
338 int ZOOM_connection_error(ZOOM_connection c, const char **cp,
339 const char **addinfo);
340 int ZOOM_connection_error_x(ZOOM_connection c, const char **cp,
341 const char **addinfo, const char **dset);
344 Function <function>ZOOM_connection_error</function> checks for
345 errors for the last operation(s) performed. The function returns
346 zero if no errors occurred; non-zero otherwise indicating the error.
347 Pointers <parameter>cp</parameter> and <parameter>addinfo</parameter>
348 holds messages for the error and additional-info if passed as
349 non-<literal>NULL</literal>. Function
350 <function>ZOOM_connection_error_x</function> is an extended version
351 of <function>ZOOM_connection_error</function> that is capable of
352 returning name of diagnostic set in <parameter>dset</parameter>.
354 <sect2 id="zoom-connection-z39.50">
355 <title>Z39.50 Protocol behavior</title>
357 The calls <function>ZOOM_connection_new</function> and
358 <function>ZOOM_connection_connect</function> establishes a TCP/IP
359 connection and sends an Initialize Request to the target if
360 possible. In addition, the calls waits for an Initialize Response
361 from the target and the result is inspected (OK or rejected).
364 If <literal>proxy</literal> is set then the client will establish
365 a TCP/IP connection with the peer as specified by the
366 <literal>proxy</literal> host and the hostname as part of the
367 connect calls will be set as part of the Initialize Request.
368 The proxy server will then "forward" the PDU's transparently
369 to the target behind the proxy.
372 For the authentication parameters, if option <literal>user</literal>
373 is set and both options <literal>group</literal> and
374 <literal>pass</literal> are unset, then Open style
375 authentication is used (Version 2/3) in which case the username
376 is usually followed by a slash, then by a password.
377 If either <literal>group</literal>
378 or <literal>pass</literal> is set then idPass authentication
379 (Version 3 only) is used. If none of the options are set, no
380 authentication parameters are set as part of the Initialize Request
384 When option <literal>async</literal> is 1, it really means that
385 all network operations are postponed (and queued) until the
386 function <literal>ZOOM_event</literal> is invoked. When doing so
387 it doesn't make sense to check for errors after
388 <literal>ZOOM_connection_new</literal> is called since that
389 operation "connecting - and init" is still incomplete and the
390 API cannot tell the outcome (yet).
393 <sect2 id="zoom.sru.init.behavior">
394 <title>SRU/SOLR Protocol behavior</title>
396 The HTTP based protocols (SRU, SRW, SOLR) doesn't feature an Inititialize Request, so
397 the connection phase merely establishes a TCP/IP connection
398 with the SOAP service.
400 <para>Most of the ZOOM connection options do not
401 affect SRU/SOLR and they are ignored. However, future versions
402 of &yaz; might honor <literal>implementationName</literal> and
403 put that as part of User-Agent header for HTTP requests.
406 The <literal>charset</literal> is used in the Content-Type header
411 <sect1 id="zoom.query"><title>Queries</title>
413 Query objects represents queries.
416 ZOOM_query ZOOM_query_create(void);
418 void ZOOM_query_destroy(ZOOM_query q);
420 int ZOOM_query_prefix(ZOOM_query q, const char *str);
422 int ZOOM_query_cql(ZOOM_query s, const char *str);
424 int ZOOM_query_sortby(ZOOM_query q, const char *criteria);
426 int ZOOM_query_sortby2(ZOOM_query q, const char *strategy,
427 const char *criteria);
430 Create query objects using <function>ZOOM_query_create</function>
431 and destroy them by calling <function>ZOOM_query_destroy</function>.
432 RPN-queries can be specified in <link linkend="PQF">PQF</link>
433 notation by using the
434 function <function>ZOOM_query_prefix</function>.
435 The <function>ZOOM_query_cql</function> specifies a CQL
436 query to be sent to the server/target.
437 More query types will be added in future versions of &yaz;, such as
438 <link linkend="CCL">CCL</link> to RPN-mapping, native CCL query,
439 etc. In addition to a search, a sort criteria may be set. Function
440 <function>ZOOM_query_sortby</function> specifies a
441 sort criteria using the same string notation for sort as offered by
442 the <link linkend="sortspec">YAZ client</link>.
445 <function>ZOOM_query_sortby2</function> is similar to
446 <function>ZOOM_query_sortby</function> but allows a strategy for
447 sorting. The reason for the strategy parameter is that some
448 protocols offers multiple ways of performing sorting.
449 For example, Z39.50 has the standard sort, which is performed after
450 search on an existing result set.
451 It's also possible to use CQL in Z39.50 as the query type and use
452 CQL's SORTBY keyword. Finally, Index Data's
453 Zebra server also allows sorting to be specified as part of RPN (Type 7).
455 <table id="zoom-sort-strategy" frame="top">
456 <title>ZOOM sort strategy</title>
458 <colspec colwidth="2*" colname="name"/>
459 <colspec colwidth="5*" colname="description"/>
463 <entry>Description</entry>
468 <entry>z39.50</entry><entry>Z39.50 resultset sort</entry>
471 <entry>type7</entry><entry>Sorting embedded in RPN(Type-7)</entry>
474 <entry>cql</entry><entry>CQL SORTBY</entry>
477 <entry>sru11</entry><entry>SRU sortKeys element</entry>
480 <entry>solr</entry><entry>Solr sort</entry>
483 <entry>embed</entry><entry>type7 for Z39.50, cql for SRU,
484 solr for Solr protocol</entry>
490 <sect1 id="zoom.resultsets"><title>Result sets</title>
492 The result set object is a container for records returned from
496 ZOOM_resultset ZOOM_connection_search(ZOOM_connection, ZOOM_query q);
498 ZOOM_resultset ZOOM_connection_search_pqf(ZOOM_connection c,
500 void ZOOM_resultset_destroy(ZOOM_resultset r);
503 Function <function>ZOOM_connection_search</function> creates
504 a result set given a connection and query.
505 Destroy a result set by calling
506 <function>ZOOM_resultset_destroy</function>.
507 Simple clients may using PQF only may use function
508 <function>ZOOM_connection_search_pqf</function> in which case
509 creating query objects is not necessary.
512 void ZOOM_resultset_option_set(ZOOM_resultset r,
513 const char *key, const char *val);
515 const char *ZOOM_resultset_option_get(ZOOM_resultset r, const char *key);
517 size_t ZOOM_resultset_size(ZOOM_resultset r);
520 Functions <function>ZOOM_resultset_options_set</function> and
521 <function>ZOOM_resultset_get</function> sets and gets an option
522 for a result set similar to <function>ZOOM_connection_option_get</function>
523 and <function>ZOOM_connection_option_set</function>.
526 The number of hits also called result-count is returned by
527 function <function>ZOOM_resultset_size</function>.
529 <table id="zoom.resultset.options"
530 frame="top"><title>ZOOM Result set Options</title>
532 <colspec colwidth="4*" colname="name"></colspec>
533 <colspec colwidth="7*" colname="description"></colspec>
534 <colspec colwidth="2*" colname="default"></colspec>
537 <entry>Option</entry>
538 <entry>Description</entry>
539 <entry>Default</entry>
544 start</entry><entry>Offset of first record to be
545 retrieved from target. First record has offset 0 unlike the
546 protocol specifications where first record has position 1.
547 This option affects ZOOM_resultset_search and
548 ZOOM_resultset_search_pqf and must be set before any of
549 these functions are invoked. If a range of
550 records must be fetched manually after search,
551 function ZOOM_resultset_records should be used.
552 </entry><entry>0</entry></row>
554 count</entry><entry>Number of records to be retrieved.
555 This option affects ZOOM_resultset_search and
556 ZOOM_resultset_search_pqf and must be set before any of
557 these functions are invoked.
558 </entry><entry>0</entry></row>
560 presentChunk</entry><entry>The number of records to be
561 requested from the server in each chunk (present request). The
562 value 0 means to request all the records in a single chunk.
563 (The old <literal>step</literal>
564 option is also supported for the benefit of old applications.)
565 </entry><entry>0</entry></row>
567 elementSetName</entry><entry>Element-Set name of records.
568 Most targets should honor element set name <literal>B</literal>
569 and <literal>F</literal> for brief and full respectively.
570 </entry><entry>none</entry></row>
572 preferredRecordSyntax</entry><entry>Preferred Syntax, such as
573 <literal>USMARC</literal>, <literal>SUTRS</literal>, etc.
574 </entry><entry>none</entry></row>
576 schema</entry><entry>Schema for retrieval, such as
577 <literal>Gils-schema</literal>, <literal>Geo-schema</literal>, etc.
578 </entry><entry>none</entry></row>
580 setname</entry><entry>Name of Result Set (Result Set ID).
581 If this option isn't set, the ZOOM module will automatically
582 allocate a result set name.
583 </entry><entry>default</entry></row>
585 rpnCharset</entry><entry>Character set for RPN terms.
586 If this is set, ZOOM C will assume that the ZOOM application is
587 running UTF-8. Terms in RPN queries are then converted to the
588 rpnCharset. If this is unset, ZOOM C will not assume any encoding
589 of RPN terms and no conversion is performed.
590 </entry><entry>none</entry></row>
595 For servers that support Search Info report, the following
596 options may be read using <function>ZOOM_resultset_get</function>.
597 This detailed information is read after a successful search has
601 This information is a list of of items, where each item is
602 information about a term or subquery. All items in the list
604 <literal>SearchResult.</literal><replaceable>no</replaceable>
605 where no presents the item number (0=first, 1=second).
606 Read <literal>searchresult.size</literal> to determine the
609 <table id="zoom.search.info.report.options"
610 frame="top"><title>Search Info Report Options</title>
612 <colspec colwidth="4*" colname="name"></colspec>
613 <colspec colwidth="7*" colname="description"></colspec>
616 <entry>Option</entry>
617 <entry>Description</entry>
622 <entry>searchresult.size</entry>
624 number of search result entries. This option is-nonexistant
625 if no entries are returned by the server.
629 <entry>searchresult.<replaceable>no</replaceable>.id</entry>
630 <entry>sub query ID</entry>
633 <entry>searchresult.<replaceable>no</replaceable>.count</entry>
634 <entry>result count for item (number of hits)</entry>
637 <entry>searchresult.<replaceable>no</replaceable>.subquery.term</entry>
638 <entry>subquery term</entry>
642 searchresult.<replaceable>no</replaceable>.interpretation.term
644 <entry>interpretation term</entry>
648 searchresult.<replaceable>no</replaceable>.recommendation.term
650 <entry>recommendation term</entry>
655 <sect2 id="zoom.z3950.resultset.behavior">
656 <title>Z39.50 Protocol behavior</title>
658 The creation of a result set involves at least a SearchRequest
659 - SearchResponse protocol handshake. Following that, if a sort
660 criteria was specified as part of the query, a SortRequest -
661 SortResponse handshake takes place. Note that it is necessary to
662 perform sorting before any retrieval takes place, so no records will
663 be returned from the target as part of the SearchResponse because these
664 would be unsorted. Hence, piggyback is disabled when sort criteria
665 are set. Following Search - and a possible sort - Retrieval takes
666 place - as one or more Present Requests/Response pairs being
670 The API allows for two different modes for retrieval. A high level
671 mode which is somewhat more powerful and a low level one.
672 The low level is enabled when searching on a Connection object
673 for which the settings
674 <literal>smallSetUpperBound</literal>,
675 <literal>mediumSetPresentNumber</literal> and
676 <literal>largeSetLowerBound</literal> are set. The low level mode
677 thus allows you to precisely set how records are returned as part
678 of a search response as offered by the Z39.50 protocol.
679 Since the client may be retrieving records as part of the
680 search response, this mode doesn't work well if sorting is used.
683 The high-level mode allows you to fetch a range of records from
684 the result set with a given start offset. When you use this mode
685 the client will automatically use piggyback if that is possible
686 with the target and perform one or more present requests as needed.
687 Even if the target returns fewer records as part of a present response
688 because of a record size limit, etc. the client will repeat sending
689 present requests. As an example, if option <literal>start</literal>
690 is 0 (default) and <literal>count</literal> is 4, and
691 <literal>piggyback</literal> is 1 (default) and no sorting criteria
692 is specified, then the client will attempt to retrieve the 4
693 records as part the search response (using piggyback). On the other
694 hand, if either <literal>start</literal> is positive or if
695 a sorting criteria is set, or if <literal>piggyback</literal>
696 is 0, then the client will not perform piggyback but send Present
700 If either of the options <literal>mediumSetElementSetName</literal> and
701 <literal>smallSetElementSetName</literal> are unset, the value
702 of option <literal>elementSetName</literal> is used for piggyback
703 searches. This means that for the high-level mode you only have
704 to specify one elementSetName option rather than three.
707 <sect2 id="zoom.sru.resultset.behavior">
708 <title>SRU Protocol behavior</title>
710 Current version of &yaz; does not take advantage of a result set id
711 returned by the SRU server. Future versions might do, however.
712 Since, the ZOOM driver does not save result set IDs any
713 present (retrieval) is transformed to a SRU SearchRetrieveRequest
714 with same query but, possibly, different offsets.
717 Option <literal>schema</literal> specifies SRU schema
718 for retrieval. However, options <literal>elementSetName</literal> and
719 <literal>preferredRecordSyntax</literal> are ignored.
722 Options <literal>start</literal> and <literal>count</literal>
723 are supported by SRU.
724 The remaining options
725 <literal>piggyback</literal>,
726 <literal>smallSetUpperBound</literal>,
727 <literal>largeSetLowerBound</literal>,
728 <literal>mediumSetPresentNumber</literal>,
729 <literal>mediumSetElementSetName</literal>,
730 <literal>smallSetElementSetName</literal> are
734 SRU supports CQL queries, <emphasis>not</emphasis> PQF.
735 If PQF is used, however, the PQF query is transferred anyway
736 using non-standard element <literal>pQuery</literal> in
737 SRU SearchRetrieveRequest.
740 SOLR queries has to be done in SOLR query format.
743 Unfortunately, SRU or SOLR does not define a database setting. Hence,
744 <literal>databaseName</literal> is unsupported and ignored.
745 However, the path part in host parameter for functions
746 <function>ZOOM_connecton_new</function> and
747 <function>ZOOM_connection_connect</function> acts as a
748 database (at least for the &yaz; SRU server).
752 <sect1 id="zoom.records"><title>Records</title>
754 A record object is a retrieval record on the client side -
755 created from result sets.
758 void ZOOM_resultset_records(ZOOM_resultset r,
760 size_t start, size_t count);
761 ZOOM_record ZOOM_resultset_record(ZOOM_resultset s, size_t pos);
763 const char *ZOOM_record_get(ZOOM_record rec, const char *type,
766 int ZOOM_record_error(ZOOM_record rec, const char **msg,
767 const char **addinfo, const char **diagset);
769 ZOOM_record ZOOM_record_clone(ZOOM_record rec);
771 void ZOOM_record_destroy(ZOOM_record rec);
774 References to temporary records are returned by functions
775 <function>ZOOM_resultset_records</function> or
776 <function>ZOOM_resultset_record</function>.
779 If a persistent reference to a record is desired
780 <function>ZOOM_record_clone</function> should be used.
781 It returns a record reference that should be destroyed
782 by a call to <function>ZOOM_record_destroy</function>.
785 A single record is returned by function
786 <function>ZOOM_resultset_record</function> that takes a
787 position as argument. First record has position zero.
788 If no record could be obtained <literal>NULL</literal> is returned.
791 Error information for a record can be checked with
792 <function>ZOOM_record_error</function> which returns non-zero
793 (error code) if record is in error, called <emphasis>Surrogate
794 Diagnostics</emphasis> in Z39.50.
797 Function <function>ZOOM_resultset_records</function> retrieves
798 a number of records from a result set. Parameter <literal>start</literal>
799 and <literal>count</literal> specifies the range of records to
800 be returned. Upon completion array
801 <literal>recs[0], ..recs[count-1]</literal>
802 holds record objects for the records. The array of records
803 <literal>recs</literal> should be allocated prior the call
804 <function>ZOOM_resultset_records</function>. Note that for those
805 records that couldn't be retrieved from the target
806 <literal>recs[ ..]</literal> is set to <literal>NULL</literal>.
808 <para id="zoom.record.get">
809 In order to extract information about a single record,
810 <function>ZOOM_record_get</function> is provided. The
811 function returns a pointer to certain record information. The
812 nature (type) of the pointer depends on the parameter,
813 <parameter>type</parameter>.
816 The <parameter>type</parameter> is a string of the format:
819 <replaceable>format</replaceable>[;charset=<replaceable>from</replaceable>[/<replaceable>opacfrom</replaceable>][,<replaceable>to</replaceable>]][;format=<replaceable>v</replaceable>]
822 where <replaceable>format</replaceable> specifies the format of the
823 returned record, <replaceable>from</replaceable>
824 specifies the character set of the record in its original form
825 (as returned by the server), <replaceable>to</replaceable> specifies
826 the output (returned)
827 character set encoding.
828 If <replaceable>to</replaceable> is omitted UTF-8 is assumed.
829 If charset is not given, then no character set conversion takes place.
832 <para>OPAC records may be returned in a different
833 set from the bibliographic MARC record. If this is this the case,
834 <replaceable>opacfrom</replaceable> should be set to the character set
835 of the OPAC record part.
839 Specifying the OPAC record character set requires YAZ 4.1.5 or later.
843 The format argument controls whether record data should be XML
844 pretty-printed (post process operation).
845 It is enabled only if format value <replaceable>v</replaceable> is
846 <literal>1</literal> and the record content is XML well-formed.
849 In addition, for certain types, the length
850 <literal>len</literal> passed will be set to the size in bytes of
851 the returned information.
854 The following are the supported values for <replaceable>form</replaceable>.
856 <varlistentry><term><literal>database</literal></term>
857 <listitem><para>Database of record is returned
858 as a C null-terminated string. Return type
859 <literal>const char *</literal>.
862 <varlistentry><term><literal>syntax</literal></term>
863 <listitem><para>The transfer syntax of the record is returned
864 as a C null-terminated string containing the symbolic name of
865 the record syntax, e.g. <literal>Usmarc</literal>. Return type
867 <literal>const char *</literal>.
870 <varlistentry><term><literal>schema</literal></term>
871 <listitem><para>The schema of the record is returned
872 as a C null-terminated string. Return type is
873 <literal>const char *</literal>.
876 <varlistentry><term><literal>render</literal></term>
877 <listitem><para>The record is returned in a display friendly
878 format. Upon completion buffer is returned
879 (type <literal>const char *</literal>) and length is stored in
880 <literal>*len</literal>.
883 <varlistentry><term><literal>raw</literal></term>
884 <listitem><para>The record is returned in the internal
885 YAZ specific format. For GRS-1, Explain, and others, the
886 raw data is returned as type
887 <literal>Z_External *</literal> which is just the type for
888 the member <literal>retrievalRecord</literal> in
889 type <literal>NamePlusRecord</literal>.
890 For SUTRS and octet aligned record (including all MARCs) the
891 octet buffer is returned and the length of the buffer.
894 <varlistentry><term><literal>xml</literal></term>
895 <listitem><para>The record is returned in XML if possible.
896 SRU, SOLR and Z39.50 records with transfer syntax XML are
897 returned verbatim. MARC records are returned in
898 <ulink url="&url.marcxml;">
901 (converted from ISO2709 to MARCXML by YAZ).
902 OPAC records are also converted to XML and the
903 bibliographic record is converted to MARCXML (when possible).
904 GRS-1 records are not supported for this form.
905 Upon completion, the XML buffer is returned
906 (type <literal>const char *</literal>) and length is stored in
907 <literal>*len</literal>.
910 <varlistentry><term><literal>opac</literal></term>
911 <listitem><para>OPAC information for record is returned in XML
912 if an OPAC record is present at the position given. If no
913 OPAC record is present, a NULL pointer is returned.
916 <varlistentry><term><literal>txml</literal></term>
917 <listitem><para>The record is returned in TurboMARC if possible.
918 SRU and Z39.50 records with transfer syntax XML are
919 returned verbatim. MARC records are returned in
920 <link linkend="tools.turbomarc">
923 (converted from ISO2709 to TurboMARC by YAZ).
924 Upon completion, the XML buffer is returned
925 (type <literal>const char *</literal>) and length is stored in
926 <literal>*len</literal>.
933 <ulink url="&url.marc21;">MARC21</ulink>
935 <ulink url="&url.marc8;">MARC-8</ulink>
936 character set encoding.
937 An application that wishes to display in Latin-1 would use
939 render; charset=marc8,iso-8859-1
942 <sect2 id="zoom.z3950.record.behavior">
943 <title>Z39.50 Protocol behavior</title>
945 The functions <function>ZOOM_resultset_record</function> and
946 <function>ZOOM_resultset_records</function> inspects the client-side
947 record cache. Records not found in cache are fetched using
949 The functions may block (and perform network I/O) - even though option
950 <literal>async</literal> is 1, because they return records objects.
951 (and there's no way to return records objects without retrieving them!).
954 There is a trick, however, in the usage of function
955 <function>ZOOM_resultset_records</function> that allows for
956 delayed retrieval (and makes it non-blocking). By using
957 a null pointer for <parameter>recs</parameter> you're indicating
958 you're not interested in getting records objects
959 <emphasis>now</emphasis>.
962 <sect2 id="zoom.sru.record.behavior">
963 <title>SRU/SOLR Protocol behavior</title>
965 The ZOOM driver for SRU/SOLR treats records returned by a SRU/SOLR server
966 as if they where Z39.50 records with transfer syntax XML and
967 no element set name or database name.
971 <sect1 id="zoom.facets"><title>Facets</title>
973 Facets operations is not part of the official ZOOM specification, but
974 is an Index Data extension for YAZ-based Z39.50 targets or
975 <ulink url="&url.solr;">SOLR</ulink> targets.
976 In case the target can and is requested to return facets, using a
977 result set the ZOOM client can request one or all facet fields.
978 Using a facet field the client can request the term count and then
979 interate over the terms.
982 ZOOM_facet_field *ZOOM_resultset_facets(ZOOM_resultset r);
984 const char ** ZOOM_resultset_facets_names(ZOOM_resultset r);
986 ZOOM_facet_field ZOOM_resultset_get_facet_field(ZOOM_resultset r,
987 const char *facet_name);
989 ZOOM_facet_field ZOOM_resultset_get_facet_field_by_index(ZOOM_resultset r,
992 size_t ZOOM_resultset_facets_size(ZOOM_resultset r);
994 const char *ZOOM_facet_field_name(ZOOM_facet_field facet_field);
996 size_t ZOOM_facet_field_term_count(ZOOM_facet_field facet_field);
998 const char *ZOOM_facet_field_get_term(ZOOM_facet_field facet_field,
999 size_t idx, int *freq);
1002 References to temporary structures are returned by all functions.
1003 They are only valid as long the Result set is valid.
1004 <function>ZOOM_resultset_get_facet_field</function> or
1005 <function>ZOOM_resultset_get_facet_field_by_index</function>.
1006 <function>ZOOM_resultset_facets</function>.
1007 <function>ZOOM_resultset_facets_names</function>.
1008 <function>ZOOM_facet_field_name</function>.
1009 <function>ZOOM_facet_field_get_term</function>.
1011 <para id="zoom.resultset.get_facet_field">
1012 A single Facet field is returned by function
1013 <function>ZOOM_resultset_get_facet_field</function> or
1014 <function>ZOOM_resultset_get_facet_field_by_index</function> that takes
1015 a result set and facet name or positive index respectively. First
1016 facet has position zero. If no facet could be obtained (invalid name
1017 or index out of bounds) <literal>NULL</literal> is returned.
1019 <para id="zoom.resultset.facets">
1020 An array of facets field can be returned by
1021 <function>ZOOM_resultset_facets</function>. The length of the array is
1022 given by <function>ZOOM_resultset_facets_size</function>. The array is
1023 zero-based and last entry will be at
1024 <function>ZOOM_resultset_facets_size(result_set)</function>-1.
1026 <para id="zoom.resultset.facets_names">
1027 It is possible to interate over facets by name, by calling
1028 <function>ZOOM_resultset_facets_names</function>.
1029 This will return an const array of char * where each string can be used
1030 as parameter for <function>ZOOM_resultset_get_facet_field</function>.
1033 Function <function>ZOOM_facet_field_name</function> gets the request
1034 facet name from a returned facet field.
1037 Function <function>ZOOM_facet_field_get_term</function> returns the
1038 idx'th term and term count for a facet field.
1039 Idx must between 0 and
1040 <function>ZOOM_facet_field_term_count</function>-1, otherwise the
1041 returned reference will be <literal>NULL</literal>. On a valid idx, the
1042 value of the freq reference will be the term count.
1043 The <literal>freq</literal> parameter must be valid pointer to integer.
1046 <sect1 id="zoom.scan"><title>Scan</title>
1048 This section describes an interface for Scan. Scan is not an
1049 official part of the ZOOM model yet. The result of a scan operation
1050 is the <literal>ZOOM_scanset</literal> which is a set of terms
1051 returned by a target.
1055 The Scan interface is supported for both Z39.50, SRU (and SOLR?).
1059 ZOOM_scanset ZOOM_connection_scan(ZOOM_connection c,
1060 const char *startpqf);
1062 ZOOM_scanset ZOOM_connection_scan1(ZOOM_connection c,
1065 size_t ZOOM_scanset_size(ZOOM_scanset scan);
1067 const char *ZOOM_scanset_term(ZOOM_scanset scan, size_t pos,
1068 size_t *occ, size_t *len);
1070 const char *ZOOM_scanset_display_term(ZOOM_scanset scan, size_t pos,
1071 size_t *occ, size_t *len);
1073 void ZOOM_scanset_destroy(ZOOM_scanset scan);
1075 const char *ZOOM_scanset_option_get(ZOOM_scanset scan,
1078 void ZOOM_scanset_option_set(ZOOM_scanset scan, const char *key,
1082 The scan set is created by function
1083 <function>ZOOM_connection_scan</function> which performs a scan
1084 operation on the connection using the specified
1085 <parameter>startpqf</parameter>.
1086 If the operation was successful, the size of the scan set can be
1087 retrieved by a call to <function>ZOOM_scanset_size</function>.
1088 Like result sets, the items are numbered 0,..size-1.
1089 To obtain information about a particular scan term, call function
1090 <function>ZOOM_scanset_term</function>. This function takes
1091 a scan set offset <literal>pos</literal> and returns a pointer
1092 to a <emphasis>raw term</emphasis> or <literal>NULL</literal> if
1094 If present, the <literal>occ</literal> and <literal>len</literal>
1095 are set to the number of occurrences and the length
1096 of the actual term respectively.
1097 <function>ZOOM_scanset_display_term</function> is similar to
1098 <function>ZOOM_scanset_term</function> except that it returns
1099 the <emphasis>display term</emphasis> rather than the raw term.
1100 In a few cases, the term is different from display term. Always
1101 use the display term for display and the raw term for subsequent
1102 scan operations (to get more terms, next scan result, etc).
1105 A scan set may be freed by a call to function
1106 <function>ZOOM_scanset_destroy</function>.
1107 Functions <function>ZOOM_scanset_option_get</function> and
1108 <function>ZOOM_scanset_option_set</function> retrieves and sets
1109 an option respectively.
1113 The <parameter>startpqf</parameter> is a subset of PQF, namely
1114 the Attributes+Term part. Multiple <literal>@attr</literal> can
1115 be used. For example to scan in title (complete) phrases:
1117 @attr 1=4 @attr 6=2 "science o"
1122 The <function>ZOOM_connecton_scan1</function> is a newer and
1123 more generic alternative to <function>ZOOM_connection_scan</function>
1124 which allows to use both CQL and PQF for Scan.
1127 <table frame="top" id="zoom.scanset.options">
1128 <title>ZOOM Scan Set Options</title>
1130 <colspec colwidth="4*" colname="name"></colspec>
1131 <colspec colwidth="7*" colname="description"></colspec>
1132 <colspec colwidth="2*" colname="default"></colspec>
1135 <entry>Option</entry>
1136 <entry>Description</entry>
1137 <entry>Default</entry>
1142 number</entry><entry>Number of Scan Terms requested in next scan.
1143 After scan it holds the actual number of terms returned.
1144 </entry><entry>20</entry></row>
1146 position</entry><entry>Preferred Position of term in response
1147 in next scan; actual position after completion of scan.
1148 </entry><entry>1</entry></row>
1150 stepSize</entry><entry>Step Size
1151 </entry><entry>0</entry></row>
1153 scanStatus</entry><entry>An integer indicating the Scan Status
1155 </entry><entry>0</entry></row>
1157 rpnCharset</entry><entry>Character set for RPN terms.
1158 If this is set, ZOOM C will assume that the ZOOM application is
1159 running UTF-8. Terms in RPN queries are then converted to the
1160 rpnCharset. If this is unset, ZOOM C will not assume any encoding
1161 of RPN terms and no conversion is performed.
1162 </entry><entry>none</entry></row>
1168 <sect1 id="zoom.extendedservices"><title>Extended Services</title>
1170 ZOOM offers an interface to a subset of the Z39.50 extended services
1171 as well as a few privately defined ones:
1176 Z39.50 Item Order (ILL).
1177 See <xref linkend="zoom.item.order"/>.
1182 Record Update. This allows a client to insert, modify or delete
1184 See <xref linkend="zoom.record.update"/>.
1189 Database Create. This a non-standard feature. Allows a client
1190 to create a database.
1191 See <xref linkend="zoom.database.create"/>.
1196 Database Drop. This a non-standard feature. Allows a client
1197 to delete/drop a database.
1198 See <xref linkend="zoom.database.drop"/>.
1203 Commit operation. This a non-standard feature. Allows a client
1204 to commit operations.
1205 See <xref linkend="zoom.commit"/>.
1208 <!-- all the ILL PDU options should go here too -->
1211 To create an extended service operation a <literal>ZOOM_package</literal>
1212 must be created. The operation is a five step operation. The
1213 package is created, package is configured by means of options,
1214 the package is send, result is inspected (by means of options),
1215 the package is destroyed.
1218 ZOOM_package ZOOM_connection_package(ZOOM_connection c,
1219 ZOOM_options options);
1221 const char *ZOOM_package_option_get(ZOOM_package p,
1223 void ZOOM_package_option_set(ZOOM_package p, const char *key,
1225 void ZOOM_package_send(ZOOM_package p, const char *type);
1227 void ZOOM_package_destroy(ZOOM_package p);
1230 The <function>ZOOM_connection_package</function> creates a
1231 package for the connection given using the options specified.
1234 Functions <function>ZOOM_package_option_get</function> and
1235 <function>ZOOM_package_option_set</function> gets and sets
1239 <function>ZOOM_package_send</function> sends
1240 the package the via connection specified in
1241 <function>ZOOM_connection_package</function>.
1242 The <parameter>type</parameter> specifies the actual extended service
1243 package type to be sent.
1246 <table frame="top" id="zoom.extendedservices.options">
1247 <title>Extended Service Common Options</title>
1249 <colspec colwidth="4*" colname="name"></colspec>
1250 <colspec colwidth="7*" colname="description"></colspec>
1251 <colspec colwidth="3*" colname="default"></colspec>
1254 <entry>Option</entry>
1255 <entry>Description</entry>
1256 <entry>Default</entry>
1261 <entry>package-name</entry>
1262 <entry>Extended Service Request package name. Must be specified
1263 as part of a request</entry>
1267 <entry>user-id</entry>
1268 <entry>User ID of Extended Service Package. Is a request option</entry>
1272 <entry>function</entry>
1274 Function of package - one of <literal>create</literal>,
1275 <literal>delete</literal>, <literal>modify</literal>. Is
1278 <entry><literal>create</literal></entry>
1281 <entry>waitAction</entry>
1283 Wait action for package. Possible values:
1284 <literal>wait</literal>, <literal>waitIfPossible</literal>,
1285 <literal>dontWait</literal> or <literal>dontReturnPackage</literal>.
1287 <entry><literal>waitIfPossible</literal></entry>
1290 <entry>targetReference</entry>
1292 Target Reference. This is part of the response as returned
1293 by the server. Read it after a successful operation.
1295 <entry><literal>none</literal></entry>
1301 <sect2 id="zoom.item.order"><title>Item Order</title>
1303 For Item Order, type must be set to <literal>itemorder</literal> in
1304 <function>ZOOM_package_send</function>.
1307 <table frame="top" id="zoom.item.order.options">
1308 <title>Item Order Options</title>
1310 <colspec colwidth="4*" colname="name"></colspec>
1311 <colspec colwidth="7*" colname="description"></colspec>
1312 <colspec colwidth="3*" colname="default"></colspec>
1315 <entry>Option</entry>
1316 <entry>Description</entry>
1317 <entry>Default</entry>
1322 <entry>contact-name</entry>
1323 <entry>ILL contact name</entry>
1327 <entry>contact-phone</entry>
1328 <entry>ILL contact phone</entry>
1332 <entry>contact-email</entry>
1333 <entry>ILL contact email</entry>
1337 <entry>itemorder-item</entry>
1338 <entry>Position for item (record) requested. An integer</entry>
1347 <sect2 id="zoom.record.update"><title>Record Update</title>
1349 For Record Update, type must be set to <literal>update</literal> in
1350 <function>ZOOM_package_send</function>.
1353 <table frame="top" id="zoom.record.update.options">
1354 <title>Record Update Options</title>
1356 <colspec colwidth="4*" colname="name"></colspec>
1357 <colspec colwidth="7*" colname="description"></colspec>
1358 <colspec colwidth="3*" colname="default"></colspec>
1361 <entry>Option</entry>
1362 <entry>Description</entry>
1363 <entry>Default</entry>
1368 <entry>action</entry>
1370 The update action. One of
1371 <literal>specialUpdate</literal>,
1372 <literal>recordInsert</literal>,
1373 <literal>recordReplace</literal>,
1374 <literal>recordDelete</literal>,
1375 <literal>elementUpdate</literal>.
1377 <entry><literal>specialUpdate (recordInsert for updateVersion=1 which does not support specialUpdate)</literal></entry>
1380 <entry>recordIdOpaque</entry>
1381 <entry>Opaque Record ID</entry>
1385 <entry>recordIdNumber</entry>
1386 <entry>Record ID number</entry>
1390 <entry>record</entry>
1391 <entry>The record itself</entry>
1395 <entry>recordOpaque</entry>
1396 <entry>Specifies an opaque record which is
1397 encoded as an ASN.1 ANY type with the OID as tiven by option
1398 <literal>syntax</literal> (see below).
1399 Option <literal>recordOpaque</literal> is an alternative
1400 to record - and <literal>record</literal> option (above) is
1401 ignored if recordOpaque is set. This option is only available in
1402 YAZ 3.0.35 and later and is meant to facilitate Updates with
1408 <entry>syntax</entry>
1409 <entry>The record syntax (transfer syntax). Is a string that
1410 is a known record syntax.
1412 <entry>no syntax</entry>
1415 <entry>databaseName</entry>
1416 <entry>Database from connection object</entry>
1417 <entry>Default</entry>
1420 <entry>correlationInfo.note</entry>
1421 <entry>Correlation Info Note (string)</entry>
1425 <entry>correlationInfo.id</entry>
1426 <entry>Correlation Info ID (integer)</entry>
1430 <entry>elementSetName</entry>
1431 <entry>Element Set for Record</entry>
1435 <entry>updateVersion</entry>
1436 <entry>Record Update version which holds one of the values
1437 1, 2 or 3. Each version has a distinct OID:
1439 (<ulink url="&url.z39.50.extupdate1;">first version</ulink>) ,
1441 (second version) and
1442 1.2.840.10003.9.5.1.1
1443 (<ulink url="&url.z39.50.extupdate3;">third and
1444 newest version</ulink>).
1454 <sect2 id="zoom.database.create"><title>Database Create</title>
1456 For Database Create, type must be set to <literal>create</literal> in
1457 <function>ZOOM_package_send</function>.
1460 <table frame="top" id="zoom.database.create.options">
1461 <title>Database Create Options</title>
1463 <colspec colwidth="4*" colname="name"></colspec>
1464 <colspec colwidth="7*" colname="description"></colspec>
1465 <colspec colwidth="3*" colname="default"></colspec>
1468 <entry>Option</entry>
1469 <entry>Description</entry>
1470 <entry>Default</entry>
1475 <entry>databaseName</entry>
1476 <entry>Database from connection object</entry>
1477 <entry>Default</entry>
1484 <sect2 id="zoom.database.drop"><title>Database Drop</title>
1486 For Database Drop, type must be set to <literal>drop</literal> in
1487 <function>ZOOM_package_send</function>.
1490 <table frame="top" id="zoom.database.drop.options">
1491 <title>Database Drop Options</title>
1493 <colspec colwidth="4*" colname="name"></colspec>
1494 <colspec colwidth="7*" colname="description"></colspec>
1495 <colspec colwidth="3*" colname="default"></colspec>
1498 <entry>Option</entry>
1499 <entry>Description</entry>
1500 <entry>Default</entry>
1505 <entry>databaseName</entry>
1506 <entry>Database from connection object</entry>
1507 <entry>Default</entry>
1514 <sect2 id="zoom.commit"><title>Commit Operation</title>
1516 For Commit, type must be set to <literal>commit</literal> in
1517 <function>ZOOM_package_send</function>.
1521 <sect2 id="zoom.extended.services.behavior">
1522 <title>Protocol behavior</title>
1524 All the extended services are Z39.50-only.
1528 The database create, drop and commit services are privately defined
1530 Refer to <filename>esadmin.asn</filename> in YAZ for the ASN.1
1537 <sect1 id="zoom.options"><title>Options</title>
1539 Most &zoom; objects provide a way to specify options to change behavior.
1540 From an implementation point of view a set of options is just like
1541 an associative array / hash.
1544 ZOOM_options ZOOM_options_create(void);
1546 ZOOM_options ZOOM_options_create_with_parent(ZOOM_options parent);
1548 void ZOOM_options_destroy(ZOOM_options opt);
1551 const char *ZOOM_options_get(ZOOM_options opt, const char *name);
1553 void ZOOM_options_set(ZOOM_options opt, const char *name,
1557 typedef const char *(*ZOOM_options_callback)
1558 (void *handle, const char *name);
1560 ZOOM_options_callback
1561 ZOOM_options_set_callback(ZOOM_options opt,
1562 ZOOM_options_callback c,
1566 <sect1 id="zoom.events"><title>Events</title>
1568 If you're developing non-blocking applications, you have to deal
1572 int ZOOM_event(int no, ZOOM_connection *cs);
1575 The <function>ZOOM_event</function> executes pending events for
1576 a number of connections. Supply the number of connections in
1577 <literal>no</literal> and an array of connections in
1578 <literal>cs</literal> (<literal>cs[0] ... cs[no-1]</literal>).
1579 A pending event could be a sending a search, receiving a response,
1581 When an event has occurred for one of the connections, this function
1582 returns a positive integer <literal>n</literal> denoting that an event
1583 occurred for connection <literal>cs[n-1]</literal>.
1584 When no events are pending for the connections, a value of zero is
1586 To ensure that all outstanding requests are performed call this function
1587 repeatedly until zero is returned.
1590 If <function>ZOOM_event</function> returns and returns non-zero, the
1591 last event that occurred can be expected.
1594 int ZOOM_connection_last_event(ZOOM_connection cs);
1597 <function>ZOOM_connection_last_event</function> returns an event type
1598 (integer) for the last event.
1601 <table frame="top" id="zoom.event.ids">
1602 <title>ZOOM Event IDs</title>
1604 <colspec colwidth="4*" colname="name"></colspec>
1605 <colspec colwidth="7*" colname="description"></colspec>
1608 <entry>Event</entry>
1609 <entry>Description</entry>
1614 <entry>ZOOM_EVENT_NONE</entry>
1615 <entry>No event has occurred</entry>
1618 <entry>ZOOM_EVENT_CONNECT</entry>
1619 <entry>TCP/IP connect has initiated</entry>
1622 <entry>ZOOM_EVENT_SEND_DATA</entry>
1623 <entry>Data has been transmitted (sending)</entry>
1626 <entry>ZOOM_EVENT_RECV_DATA</entry>
1627 <entry>Data has been received)</entry>
1630 <entry>ZOOM_EVENT_TIMEOUT</entry>
1631 <entry>Timeout</entry>
1634 <entry>ZOOM_EVENT_UNKNOWN</entry>
1635 <entry>Unknown event</entry>
1638 <entry>ZOOM_EVENT_SEND_APDU</entry>
1639 <entry>An APDU has been transmitted (sending)</entry>
1642 <entry>ZOOM_EVENT_RECV_APDU</entry>
1643 <entry>An APDU has been received</entry>
1646 <entry>ZOOM_EVENT_RECV_RECORD</entry>
1647 <entry>A result-set record has been received</entry>
1650 <entry>ZOOM_EVENT_RECV_SEARCH</entry>
1651 <entry>A search result been received</entry>
1659 <!-- Keep this comment at the end of the file
1664 sgml-minimize-attributes:nil
1665 sgml-always-quote-attributes:t
1668 sgml-parent-document: "yaz.xml"
1669 sgml-local-catalogs: nil
1670 sgml-namecase-general:t