+ * Revision 1.93 1999-06-17 14:38:40 adam
+ * Bug fix: Scan SEGV'ed when getting unknown use attribute.
+ *
+ * Revision 1.92 1999/05/26 07:49:13 adam
+ * C++ compilation.
+ *
+ * Revision 1.91 1999/02/02 14:51:13 adam
+ * Updated WIN32 code specific sections. Changed header.
+ *
+ * Revision 1.90 1998/11/16 16:03:43 adam
+ * Moved loggin utilities to Yaz. Was implemented in file zlogs.c.
+ *
+ * Revision 1.89 1998/11/16 10:11:55 adam
+ * Added addtional info for error 114 - unsupported use attribute.
+ *
+ * Revision 1.88 1998/10/18 07:54:52 adam
+ * Additional info added for diagnostics 114 (Unsupported use attribute) and
+ * 121 (Unsupported attribute set).
+ *
+ * Revision 1.87 1998/09/28 11:19:12 adam
+ * Fix for Compiled ASN.1.
+ *
+ * Revision 1.86 1998/09/22 10:48:20 adam
+ * Minor changes in search API.
+ *
+ * Revision 1.85 1998/09/22 10:03:43 adam
+ * Changed result sets to be persistent in the sense that they can
+ * be re-searched if needed.
+ * Fixed memory leak in rsm_or.
+ *
+ * Revision 1.84 1998/09/18 12:41:00 adam
+ * Fixed bug with numerical relations.
+ *
+ * Revision 1.83 1998/09/02 13:53:19 adam
+ * Extra parameter decode added to search routines to implement
+ * persistent queries.
+ *
+ * Revision 1.82 1998/06/26 11:16:40 quinn
+ * Added support (un-optimised) for left and left/right truncation
+ *
+ * Revision 1.81 1998/06/24 12:16:14 adam
+ * Support for relations on text operands. Open range support in
+ * DFA module (i.e. [-j], [g-]).
+ *
+ * Revision 1.80 1998/06/23 15:33:34 adam
+ * Added feature to specify sort criteria in query (type 7 specifies
+ * sort flags).
+ *
+ * Revision 1.79 1998/06/22 11:35:09 adam
+ * Minor changes.
+ *
+ * Revision 1.78 1998/06/08 14:43:17 adam
+ * Added suport for EXPLAIN Proxy servers - added settings databasePath
+ * and explainDatabase to facilitate this. Increased maximum number
+ * of databases and attributes in one register.
+ *
+ * Revision 1.77 1998/05/20 10:12:22 adam
+ * Implemented automatic EXPLAIN database maintenance.
+ * Modified Zebra to work with ASN.1 compiled version of YAZ.
+ *
+ * Revision 1.76 1998/04/02 14:35:29 adam
+ * First version of Zebra that works with compiled ASN.1.
+ *
+ * Revision 1.75 1998/03/05 08:45:13 adam
+ * New result set model and modular ranking system. Moved towards
+ * descent server API. System information stored as "SGML" records.
+ *
+ * Revision 1.74 1998/02/10 12:03:06 adam
+ * Implemented Sort.
+ *
+ * Revision 1.73 1998/01/29 13:40:11 adam
+ * Better logging for scan service.
+ *
+ * Revision 1.72 1998/01/07 13:53:41 adam
+ * Queries using simple ranked operands returns right number of hits.
+ *
+ * Revision 1.71 1997/12/18 10:54:24 adam
+ * New method result set method rs_hits that returns the number of
+ * hits in result-set (if known). The ranked result set returns real
+ * number of hits but only when not combined with other operands.
+ *
+ * Revision 1.70 1997/10/31 12:34:43 adam
+ * Changed a few log statements.
+ *
+ * Revision 1.69 1997/10/29 12:05:02 adam
+ * Server produces diagnostic "Unsupported Attribute Set" when appropriate.
+ *
+ * Revision 1.68 1997/10/27 14:33:06 adam
+ * Moved towards generic character mapping depending on "structure"
+ * field in abstract syntax file. Fixed a few memory leaks. Fixed
+ * bug with negative integers when doing searches with relational
+ * operators.
+ *
+ * Revision 1.67 1997/09/29 09:06:10 adam
+ * Removed one static var in order to make this module thread safe.
+ *
+ * Revision 1.66 1997/09/25 14:58:03 adam
+ * Windows NT port.
+ *
+ * Revision 1.65 1997/09/22 12:39:06 adam
+ * Added get_pos method for the ranked result sets.
+ *
+ * Revision 1.64 1997/09/18 08:59:20 adam
+ * Extra generic handle for the character mapping routines.
+ *
+ * Revision 1.63 1997/09/17 12:19:18 adam
+ * Zebra version corresponds to YAZ version 1.4.
+ * Changed Zebra server so that it doesn't depend on global common_resource.
+ *
+ * Revision 1.62 1997/09/05 15:30:09 adam
+ * Changed prototype for chr_map_input - added const.
+ * Added support for C++, headers uses extern "C" for public definitions.
+ *
+ * Revision 1.61 1997/02/10 10:21:14 adam
+ * Bug fix: in search terms character (^) wasn't observed.
+ *
+ * Revision 1.60 1997/01/31 11:10:34 adam
+ * Bug fix: Leading and trailing white space weren't removed in scan tokens.
+ *
+ * Revision 1.59 1997/01/17 11:31:46 adam
+ * Bug fix: complete phrase search didn't work.
+ *
+ * Revision 1.58 1996/12/23 15:30:45 adam
+ * Work on truncation.
+ * Bug fix: result sets weren't deleted after server shut down.
+ *
+ * Revision 1.57 1996/11/11 13:38:02 adam
+ * Added proximity support in search.
+ *
+ * Revision 1.56 1996/11/08 11:10:32 adam
+ * Buffers used during file match got bigger.
+ * Compressed ISAM support everywhere.
+ * Bug fixes regarding masking characters in queries.
+ * Redesigned Regexp-2 queries.
+ *
+ * Revision 1.55 1996/11/04 14:07:44 adam
+ * Moved truncation code to trunc.c.
+ *
+ * Revision 1.54 1996/10/29 14:09:52 adam
+ * Use of cisam system - enabled if setting isamc is 1.
+ *
+ * Revision 1.53 1996/06/26 09:21:43 adam
+ * Bug fix: local attribute set wasn't obeyed in scan.
+ *
+ * Revision 1.52 1996/06/17 14:26:20 adam
+ * Function gen_regular_rel changed to handle negative numbers.
+ *
+ * Revision 1.51 1996/06/11 10:54:15 quinn
+ * Relevance work
+ *
+ * Revision 1.50 1996/06/07 08:51:53 adam
+ * Bug fix: Character mapping was broken (introducued by last revision).
+ *
+ * Revision 1.49 1996/06/04 10:18:11 adam
+ * Search/scan uses character mapping module.
+ *
+ * Revision 1.48 1996/05/28 15:15:01 adam
+ * Bug fix: Didn't handle unknown database correctly.
+ *
+ * Revision 1.47 1996/05/15 18:36:28 adam
+ * Function trans_term transforms unsearchable characters to blanks.
+ *
+ * Revision 1.46 1996/05/15 11:57:56 adam
+ * Fixed bug introduced by set/field mapping in search operations.
+ *
+ * Revision 1.45 1996/05/14 11:34:00 adam
+ * Scan support in multiple registers/databases.
+ *
+ * Revision 1.44 1996/05/14 06:16:44 adam
+ * Compact use/set bytes used in search service.
+ *
+ * Revision 1.43 1996/05/09 09:54:43 adam
+ * Server supports maps from one logical attributes to a list of physical
+ * attributes.
+ * The extraction process doesn't make space consuming 'any' keys.
+ *
+ * Revision 1.42 1996/05/09 07:28:56 quinn
+ * Work towards phrases and multiple registers
+ *
+ * Revision 1.41 1996/03/20 09:36:43 adam
+ * Function dict_lookup_grep got extra parameter, init_pos, which marks
+ * from which position in pattern approximate pattern matching should occur.
+ * Approximate pattern matching is used in relevance=re-2.
+ *
+ * Revision 1.40 1996/02/02 13:44:44 adam
+ * The public dictionary functions simply use char instead of Dict_char
+ * to represent search strings. Dict_char is used internally only.
+ *
+ * Revision 1.39 1996/01/03 16:22:13 quinn
+ * operator->roperator
+ *
+ * Revision 1.38 1995/12/11 09:12:55 adam
+ * The rec_get function returns NULL if record doesn't exist - will
+ * happen in the server if the result set records have been deleted since
+ * the creation of the set (i.e. the search).
+ * The server saves a result temporarily if it is 'volatile', i.e. the
+ * set is register dependent.
+ *
+ * Revision 1.37 1995/12/06 15:05:28 adam
+ * More verbose in count_set.
+ *
+ * Revision 1.36 1995/12/06 12:41:27 adam
+ * New command 'stat' for the index program.
+ * Filenames can be read from stdin by specifying '-'.
+ * Bug fix/enhancement of the transformation from terms to regular
+ * expressons in the search engine.
+ *
+ * Revision 1.35 1995/11/27 09:29:00 adam
+ * Bug fixes regarding conversion to regular expressions.
+ *
+ * Revision 1.34 1995/11/16 17:00:56 adam
+ * Better logging of rpn query.
+ *
+ * Revision 1.33 1995/11/01 13:58:28 quinn
+ * Moving data1 to yaz/retrieval
+ *
+ * Revision 1.32 1995/10/27 14:00:11 adam
+ * Implemented detection of database availability.
+ *
+ * Revision 1.31 1995/10/17 18:02:10 adam
+ * New feature: databases. Implemented as prefix to words in dictionary.
+ *
+ * Revision 1.30 1995/10/16 09:32:38 adam
+ * More work on relational op.
+ *
+ * Revision 1.29 1995/10/13 16:01:49 adam
+ * Work on relations.
+ *
+ * Revision 1.28 1995/10/13 12:26:43 adam
+ * Optimization of truncation.
+ *
+ * Revision 1.27 1995/10/12 17:07:22 adam
+ * Truncation works.
+ *
+ * Revision 1.26 1995/10/12 12:40:54 adam
+ * Bug fixes in rpn_prox.
+ *
+ * Revision 1.25 1995/10/10 13:59:24 adam
+ * Function rset_open changed its wflag parameter to general flags.
+ *
+ * Revision 1.24 1995/10/09 16:18:37 adam
+ * Function dict_lookup_grep got extra client data parameter.
+ *
+ * Revision 1.23 1995/10/06 16:33:37 adam
+ * Use attribute mappings.
+ *
+ * Revision 1.22 1995/10/06 15:07:39 adam
+ * Structure 'local-number' handled.
+ *
+ * Revision 1.21 1995/10/06 13:52:06 adam
+ * Bug fixes. Handler may abort further scanning.
+ *
+ * Revision 1.20 1995/10/06 11:06:33 adam
+ * Scan entries include 'occurrences' now.
+ *
+ * Revision 1.19 1995/10/06 10:43:56 adam