This section describes an interface for Scan. Scan is not an
official part of the ZOOM model yet. The result of a scan operation
ZOOM_scanset which is a set of terms
returned by a target.
The Scan interface is supported for both Z39.50, SRU and Solr.
ZOOM_scanset ZOOM_connection_scan(ZOOM_connection c, const char *startpqf); ZOOM_scanset ZOOM_connection_scan1(ZOOM_connection c, ZOOM_query q); size_t ZOOM_scanset_size(ZOOM_scanset scan); const char *ZOOM_scanset_term(ZOOM_scanset scan, size_t pos, size_t *occ, size_t *len); const char *ZOOM_scanset_display_term(ZOOM_scanset scan, size_t pos, size_t *occ, size_t *len); void ZOOM_scanset_destroy(ZOOM_scanset scan); const char *ZOOM_scanset_option_get(ZOOM_scanset scan, const char *key); void ZOOM_scanset_option_set(ZOOM_scanset scan, const char *key, const char *val);
The scan set is created by function
ZOOM_connection_scan which performs a scan
operation on the connection using the specified
If the operation was successful, the size of the scan set can be
retrieved by a call to
Like result sets, the items are numbered 0..size-1.
To obtain information about a particular scan term, call function
ZOOM_scanset_term. This function takes
a scan set offset
pos and returns a pointer
to a raw term or
If present, the
are set to the number of occurrences and the length
of the actual term respectively.
ZOOM_scanset_display_term is similar to
ZOOM_scanset_term except that it returns
the display term rather than the raw term.
In a few cases, the term is different from display term. Always
use the display term for display and the raw term for subsequent
scan operations (to get more terms, next scan result, etc).
A scan set may be freed by a call to function
ZOOM_scanset_option_set retrieves and sets
an option respectively.
startpqf is a subset of PQF, namely
the Attributes+Term part. Multiple
be used. For example to scan in title (complete) phrases:
@attr 1=4 @attr 6=2 "science o"
ZOOM_connecton_scan1 is a newer and
more generic alternative to
which allows to use both CQL and PQF for Scan.
Table 3.5. ZOOM Scan Set Options
|number||Number of Scan Terms requested in next scan. After scan it holds the actual number of terms returned.||20|
|position||Preferred Position of term in response in next scan; actual position after completion of scan.||1|
|scanStatus||An integer indicating the Scan Status of last scan.||0|
|rpnCharset||Character set for RPN terms. If this is set, ZOOM C will assume that the ZOOM application is running UTF-8. Terms in RPN queries are then converted to the rpnCharset. If this is unset, ZOOM C will not assume any encoding of RPN terms and no conversion is performed.||none|