All changes to the CQL section:
[yaz-moved-to-github.git] / doc / tools.xml
index 450b3fc..6c02fc5 100644 (file)
@@ -1,4 +1,4 @@
-<!-- $Id: tools.xml,v 1.25 2003-06-19 23:05:29 adam Exp $ -->
+<!-- $Id: tools.xml,v 1.34 2003-12-18 17:27:31 mike Exp $ -->
  <chapter id="tools"><title>Supporting Tools</title>
   
   <para>
@@ -16,7 +16,7 @@
     <token>Z_RPNQuery</token> structure. Some programmers will prefer to
     construct the query manually, perhaps using
     <function>odr_malloc()</function> to simplify memory management.
-    The &yaz; distribution includes two separate, query-generating tools
+    The &yaz; distribution includes three separate, query-generating tools
     that may be of use to you.
    </para>
 
 
      top-set ::= &lsqb; '@attrset' string &rsqb;
 
-     query-struct ::= attr-spec | simple | complex | '@term' term-type
+     query-struct ::= attr-spec | simple | complex | '@term' term-type query
 
      attr-spec ::= '@attr' &lsqb; string &rsqb; string query-struct
 
     <para>
      The @attr operator is followed by an attribute specification 
      (<literal>attr-spec</literal> above). The specification consists
-     of optional an attribute set, an attribute type-value pair and
-     a sub query. The attribute type-value pair is packed in one string:
-     an attribute type, a dash, followed by an attribute value. 
+     of an optional attribute set, an attribute type-value pair and
+     a sub-query. The attribute type-value pair is packed in one string:
+     an attribute type, an equals sign, and an attribute value, like this:
+     <literal>@attr 1=1003</literal>.
      The type is always an integer but the value may be either an
      integer or a string (if it doesn't start with a digit character).
+     A string attribute-value is encoded as a Type-1 ``complex''
+     attribute with the list of values containing the single string
+     specified, and including no semantic indicators.
     </para>
 
     <para>
 
     <sect3 id="pqf-examples"><title>PQF queries</title>
 
-     <para>Queries using simple terms.
-      <screen>
-      dylan
-      "bob dylan"
-      </screen>
-     </para>
-     <para>Boolean operators.
-      <screen>
-       @or "dylan" "zimmerman"
-       @and @or dylan zimmerman when
-       @and when @or dylan zimmerman
-      </screen>
-     </para>
-     <para>
-      Reference to result sets.
-      <screen>
-       @set Result-1
-       @and @set seta setb
-      </screen>
-     </para>
-     <para>
-      Attributes for terms.
-      <screen>
-       @attr 1=4 computer
-       @attr 1=4 @attr 4=1 "self portrait"
-       @attr exp1 @attr 1=1 CategoryList
-       @attr gils 1=2008 Copenhagen
-       @attr 1=/book/title computer
-      </screen>
-     </para>
-     <para>
-      Proximity.
-      <screen>
-       @prox 0 3 1 2 k 2 dylan zimmerman
-      </screen>
-      <note><para>
-      Here the parameters 0, 3, 1, 2, k and 2 represent exclusion,
-      distance, ordered, relation, which-code and unit-code, in that
-      order.  So:
-      <itemizedlist>
-        <listitem><para>
-         exclusion = 0: the proximity condition must hold
-        </para></listitem>
-        <listitem><para>
-         distance = 3: the terms must be three units apart
-        </para></listitem>
-        <listitem><para>
-         ordered = 1: they must occur in the order they are specified
-        </para></listitem>
-        <listitem><para>
-         relation = 2: lessThanOrEqual (to the distance of 3 units)
-        </para></listitem>
-        <listitem><para>
-         which-code is ``known'', so the standard unit-codes are used
-        </para></listitem>
-        <listitem><para>
-         unit-code = 2: word.
-        </para></listitem>
-      </itemizedlist>
-      So the whole proximity query means that the words
-      <literal>dylan</literal> and <literal>zimmerman</literal> must
-      both occur in the record, in that order, differing in position
-      by three or fewer words (i.e. with two or fewer words between
-      them.)  The query would find ``Bob Dylan, aka. Robert
-      Zimmerman'', but not ``Bob Dylan, born as Robert Zimmerman''
-      since the distance in this case is four.
-      </para></note>
-     </para>
-     <para>
-      Specifying term type.
-      <screen>
-       @term string "a UTF-8 string, maybe?"
-      </screen>
-     </para>
-     <para>Mixed queries
-      <screen>
-       @or @and bob dylan @set Result-1
-       
-       @attr 4=1 @and @attr 1=1 "bob dylan" @attr 1=4 "slow train coming"
-       
-       @and @attr 2=4 @attr gils 1=2038 -114 @attr 2=2 @attr gils 1=2039 -109
+     <example><title>PQF queries using simple terms</title>
+      <para>
+       <screen>
+       dylan
+       "bob dylan"
+       </screen>
+      </para>
+     </example>
+     <example><title>PQF boolean operators</title>
+      <para>
+       <screen>
+       @or "dylan" "zimmerman"
+       @and @or dylan zimmerman when
+       @and when @or dylan zimmerman
+       </screen>
+      </para>
+     </example>
+     <example><title>PQF references to result sets</title>
+      <para>
+       <screen>
+       @set Result-1
+       @and @set seta setb
+       </screen>
+      </para>
+     </example>
+     <example><title>Attributes for terms</title>
+      <para>
+       <screen>
+       @attr 1=4 computer
+       @attr 1=4 @attr 4=1 "self portrait"
+       @attrset exp1 @attr 1=1 CategoryList
+       @attr gils 1=2008 Copenhagen
+       @attr 1=/book/title computer
+       </screen>
+      </para>
+     </example>
+     <example><title>PQF Proximity queries</title>
+      <para>
+       <screen>
+       @prox 0 3 1 2 k 2 dylan zimmerman
+       </screen>
+       <note><para>
+        Here the parameters 0, 3, 1, 2, k and 2 represent exclusion,
+        distance, ordered, relation, which-code and unit-code, in that
+        order.  So:
+        <itemizedlist>
+         <listitem><para>
+           exclusion = 0: the proximity condition must hold
+          </para></listitem>
+         <listitem><para>
+           distance = 3: the terms must be three units apart
+          </para></listitem>
+         <listitem><para>
+           ordered = 1: they must occur in the order they are specified
+          </para></listitem>
+         <listitem><para>
+           relation = 2: lessThanOrEqual (to the distance of 3 units)
+          </para></listitem>
+         <listitem><para>
+           which-code is ``known'', so the standard unit-codes are used
+          </para></listitem>
+         <listitem><para>
+           unit-code = 2: word.
+          </para></listitem>
+        </itemizedlist>
+        So the whole proximity query means that the words
+        <literal>dylan</literal> and <literal>zimmerman</literal> must
+        both occur in the record, in that order, differing in position
+        by three or fewer words (i.e. with two or fewer words between
+        them.)  The query would find ``Bob Dylan, aka. Robert
+        Zimmerman'', but not ``Bob Dylan, born as Robert Zimmerman''
+        since the distance in this case is four.
+       </para></note>
+      </para>
+     </example>
+     <example><title>PQF specification of search term</title>
+      <para>
+       <screen>
+       @term string "a UTF-8 string, maybe?"
+       </screen>
+      </para>
+     </example>
+     <example><title>PQF mixed queries</title>
+      <para>
+       <screen>
+       @or @and bob dylan @set Result-1
+       
+       @attr 4=1 @and @attr 1=1 "bob dylan" @attr 1=4 "slow train coming"
+       
+       @and @attr 2=4 @attr gils 1=2038 -114 @attr 2=2 @attr gils 1=2039 -109
       </screen>
-      <note>
+       <note>
        <para>
-         The last of these examples is a spatial search: in
-         <ulink url="http://www.gils.net/prof_v2.html#sec_7_4"
+        The last of these examples is a spatial search: in
+        <ulink url="http://www.gils.net/prof_v2.html#sec_7_4"
          >the GILS attribute set</ulink>,
-         access point
-         2038 indicates West Bounding Coordinate and
-         2030 indicates East Bounding Coordinate,
-         so the query is for areas extending from -114 degrees
-         to no more than -109 degrees.
+        access point
+        2038 indicates West Bounding Coordinate and
+        2030 indicates East Bounding Coordinate,
+        so the query is for areas extending from -114 degrees
+        to no more than -109 degrees.
        </para>
-      </note>
-     </para>
+       </note>
+      </para>
+     </example>
     </sect3>
    </sect2>
    <sect2 id="CCL"><title>CCL</title>
     </para>
 
     <para>
-     The <ulink url="http://europagate.dtv.dk/">EUROPAGATE</ulink>
-     research project working under the Libraries programme
+     The EUROPAGATE research project working under the Libraries programme
      of the European Commission's DG XIII has, amongst other useful tools,
      implemented a general-purpose CCL parser which produces an output
      structure that can be trivially converted to the internal RPN
        or <literal>c</literal> for completeness.
        The attributes for the special qualifier name <literal>term</literal>
        are used when no CCL qualifier is given in a query.
+       <table><title>Common Bib-1 attributes</title>
+       <tgroup cols="2">
+        <colspec colwidth="2*" colname="type"></colspec>
+        <colspec colwidth="9*" colname="description"></colspec>
+        <thead>
+         <row>
+          <entry>Type</entry>
+          <entry>Description</entry>
+         </row>
+        </thead>
+        <tbody>
+         <row>
+          <entry><literal>u=</literal><replaceable>value</replaceable></entry>
+          <entry>
+           Use attribute. Common use attributes are
+           1 Personal-name, 4 Title, 7 ISBN, 8 ISSN, 30 Date,
+           62 Subject, 1003 Author), 1016 Any. Specify value
+           as an integer.
+          </entry>
+         </row>
+
+         <row>
+          <entry><literal>r=</literal><replaceable>value</replaceable></entry>
+          <entry>
+           Relation attribute. Common values are
+           1 &lt;, 2 &lt;=, 3 =, 4 &gt;=, 5 &gt;, 6 &lt;&gt;,
+           100 phonetic, 101 stem, 102 relevance, 103 always matches.
+          </entry>
+         </row>
+
+         <row>
+          <entry><literal>p=</literal><replaceable>value</replaceable></entry>
+          <entry>
+           Position attribute. Values: 1 first in field, 2
+           first in any subfield, 3 any position in field.
+          </entry>
+         </row>
+
+         <row>
+          <entry><literal>s=</literal><replaceable>value</replaceable></entry>
+          <entry>
+           Structure attribute. Values: 1 phrase, 2 word,
+           3 key, 4 year, 5 date, 6 word list, 100 date (un),
+           101 name (norm), 102 name (un), 103 structure, 104 urx,
+           105 free-form-text, 106 document-text, 107 local-number,
+           108 string, 109 numeric string.
+          </entry>
+         </row>
+
+         <row>
+          <entry><literal>t=</literal><replaceable>value</replaceable></entry>
+          <entry>
+           Truncation attribute. Values: 1 right, 2 left,
+           3 left&amp; right, 100 none, 101 process #, 102 regular-1,
+           103 regular-2, 104 CCL.
+          </entry>
+         </row>
+
+         <row>
+          <entry><literal>c=</literal><replaceable>value</replaceable></entry>
+          <entry>
+           Completeness attribute. Values: 1 incomplete subfield,
+           2 complete subfield, 3 complete field.
+          </entry>
+         </row>
+
+        </tbody>
+        </tgroup>
+       </table>
       </para>
       <para>
-       The attribute value <replaceable>val</replaceable> may be
-       specified as in integer. It is also possible to specify
-       non-numeric values, however, which are used in combination with
-       certain types. The special combinations are:
-      <variablelist>
-       <varlistentry><term><literal>s=pw</literal></term>
-        <listitem><para>
-          The structure is set to either word or phrase depending
-          on the number of tokens in a term (phrase-word).
-         </para>
-        </listitem>
-       </varlistentry>
-       
-       <varlistentry><term><literal>s=al</literal></term>
-        <listitem><para>
-          Each token in the term is ANDed. (and-list).
-          This does not set the structure at all.
-         </para>
-        </listitem>
-       </varlistentry>
-       
-       <varlistentry><term><literal>s=ol</literal></term>
-        <listitem><para>
-         Each token in the term is ORed. (or-list).
-          This does not set the structure at all.
-        </para>
-        </listitem>
-       </varlistentry>
-       
-       <varlistentry><term><literal>r=o</literal></term>
-        <listitem><para>
-          Allows operators greather-than, less-than, ... equals and
-          sets relation attribute accordingly (relation ordered).
-         </para>
-        </listitem>
-       </varlistentry>
-       
-       <varlistentry><term><literal>t=l</literal></term>
-        <listitem><para>
-          Allows term to be left-truncated.
-          If term is of the form <literal>?x</literal>, the resulting
-          Type-1 term is <literal>x</literal> and truncation is left.
-         </para>
-        </listitem>
-       </varlistentry>
-       
-       <varlistentry><term><literal>t=r</literal></term>
-        <listitem><para>
-          Allows term to be right-truncated.
-          If term is of the form <literal>x?</literal>, the resulting
-          Type-1 term is <literal>x</literal> and truncation is right.
-         </para>
-        </listitem>
-       </varlistentry>
-       
-       <varlistentry><term><literal>t=n</literal></term>
-        <listitem><para>
-          If term is does not include <literal>?</literal>, the
-          truncation attribute is set to none (100).
-         </para>
-        </listitem>
-       </varlistentry>
-       
-       <varlistentry><term><literal>t=b</literal></term>
-        <listitem><para>
-          Allows term to be both left&amp;right truncated.
-          If term is of the form <literal>?x?</literal>, the
-          resulting term is <literal>x</literal> and trunctation is
-          set to both left&amp;right.
-         </para>
-        </listitem>
-       </varlistentry>
-       
-       </variablelist>
+       The complete list of Bib-1 attributes can be found 
+       <ulink url="http://lcweb.loc.gov/z3950/agency/defns/bib1.html">
+       here
+       </ulink>.
+      </para>
+      <para>
+       It is also possible to specify non-numeric attribute values, 
+       which are used in combination with certain types.
+       The special combinations are:
+       
+       <table><title>Special attribute combos</title>
+       <tgroup cols="2">
+        <colspec colwidth="2*" colname="name"></colspec>
+        <colspec colwidth="9*" colname="description"></colspec>
+        <thead>
+         <row>
+          <entry>Name</entry>
+          <entry>Description</entry>
+         </row>
+        </thead>
+        <tbody>
+         <row>
+          <entry><literal>s=pw</literal></entry><entry>
+           The structure is set to either word or phrase depending
+           on the number of tokens in a term (phrase-word).
+          </entry>
+         </row>
+         <row>
+          <entry><literal>s=al</literal></entry><entry>
+           Each token in the term is ANDed. (and-list).
+           This does not set the structure at all.
+          </entry>
+         </row>
+         
+         <row><entry><literal>s=ol</literal></entry><entry>
+           Each token in the term is ORed. (or-list).
+           This does not set the structure at all.
+          </entry>
+         </row>
+         
+         <row><entry><literal>r=o</literal></entry><entry>
+           Allows operators greather-than, less-than, ... equals and
+           sets relation attribute accordingly (relation ordered).
+          </entry>
+         </row>
+         
+         <row><entry><literal>t=l</literal></entry><entry>
+           Allows term to be left-truncated.
+           If term is of the form <literal>?x</literal>, the resulting
+           Type-1 term is <literal>x</literal> and truncation is left.
+          </entry>
+         </row>
+         
+         <row><entry><literal>t=r</literal></entry><entry>
+           Allows term to be right-truncated.
+           If term is of the form <literal>x?</literal>, the resulting
+           Type-1 term is <literal>x</literal> and truncation is right.
+          </entry>
+         </row>
+         
+         <row><entry><literal>t=n</literal></entry><entry>
+           If term is does not include <literal>?</literal>, the
+           truncation attribute is set to none (100).
+          </entry>
+         </row>
+         
+         <row><entry><literal>t=b</literal></entry><entry>
+           Allows term to be both left&amp;right truncated.
+           If term is of the form <literal>?x?</literal>, the
+           resulting term is <literal>x</literal> and trunctation is
+           set to both left&amp;right.
+          </entry>
+         </row>
+        </tbody>
+       </tgroup>
+       </table>
       </para>
       <example><title>CCL profile</title>
        <para>
        au       u=1 s=1
        term     s=105
        ranked   r=102
+       date     u=30 r=o
       </screen>
        <para>
-       Three qualifiers are defined, <literal>ti</literal>, 
-       <literal>au</literal> and <literal>ranked</literal>.
+       Four qualifiers are defined - <literal>ti</literal>, 
+       <literal>au</literal>, <literal>ranked</literal> and
+       <literal>date</literal>.
+       </para>
+       <para>
        <literal>ti</literal> and <literal>au</literal> both set 
        structure attribute to phrase (s=1).
        <literal>ti</literal>
        sets the use-attribute to 4. <literal>au</literal> sets the
        use-attribute to 1.
        When no qualifiers are used in the query the structure-attribute is
-       set to free-form-text (105).
-      </para>
+       set to free-form-text (105) (rule for <literal>term</literal>).
+       The <literal>date</literal> sets the relation attribute to
+       the relation used in the CCL query and sets the use attribute
+       to 30 (Bib-1 Date).
+       </para>
        <para>
        You can combine attributes. To Search for "ranked title" you
        can do 
        <screen>
         ti,ranked=knuth computer
        </screen>
-       which will use "relation is ranked", "use is title", "structure is
-       phrase".
+       which will set relation=ranked, use=title, structure=phrase.
+       </para>
+       <para>
+       Query
+       <screen>
+        year > 1980
+       </screen>
+       is a valid query, while
+       <screen>
+        ti > 1980
+       </screen>
+       is invalid.
        </para>
       </example>
      </sect4>
       </para>
       <table><title>CCL directives</title>
        <tgroup cols="3">
-       <colspec colwidth="3*" colname="name"></colspec>
-       <colspec colwidth="7*" colname="description"></colspec>
-       <colspec colwidth="2*" colname="default"></colspec>
+       <colspec colwidth="2*" colname="name"></colspec>
+       <colspec colwidth="8*" colname="description"></colspec>
+       <colspec colwidth="1*" colname="default"></colspec>
        <thead>
         <row>
          <entry>Name</entry>
@@ -1107,9 +1208,9 @@ int cql_transform_error(cql_transform_t ct, char **addinfop);
       error-code and sets the string-pointer at
       <literal>*addinfop</literal> to point to a string containing
       additional information about the error that occurred: for
-      example, if the error code is 15 (``Illegal or unsupported index
+      example, if the error code is 15 (``Illegal or unsupported context
       set''), the additional information is the name of the requested
-      index set that was not recognised.
+      context set that was not recognised.
      </para>
      <para>
       The SRW error-codes may be translated into brief human-readable
@@ -1165,26 +1266,37 @@ int cql_transform_FILE(cql_transform_t ct,
       The following CQL patterns are recognized:
       <variablelist>
        <varlistentry><term>
-         <literal>qualifier.</literal><replaceable>set</replaceable><literal>.</literal><replaceable>name</replaceable>
+         <literal>index.</literal><replaceable>set</replaceable><literal>.</literal><replaceable>name</replaceable>
         </term>
         <listitem>
          <para>
-          This pattern is invoked when a CQL qualifier, such as 
+          This pattern is invoked when a CQL index, such as 
           dc.title is converted. <replaceable>set</replaceable>
-          and <replaceable>name</replaceable> is the index set and qualifier
+          and <replaceable>name</replaceable> are the context set and index
           name respectively.
           Typically, the RPN specifies an equivalent use attribute.
          </para>
          <para>
-          For terms not bound by a qualifier the pattern
-          <literal>qualifier.srw.serverChoice</literal> is used.
-          Here, the prefix <literal>srw</literal> is defined as
-          <literal>http://www.loc.gov/zing/cql/srw-indexes/v1.0/</literal>.
+          For terms not bound by an index the pattern
+          <literal>index.cql.serverChoice</literal> is used.
+          Here, the prefix <literal>cql</literal> is defined as
+          <literal>http://www.loc.gov/zing/cql/cql-indexes/v1.0/</literal>.
           If this pattern is not defined, the mapping will fail.
          </para>
         </listitem>
        </varlistentry>
        <varlistentry><term>
+         <literal>qualifier.</literal><replaceable>set</replaceable><literal>.</literal><replaceable>name</replaceable>
+        (DEPRECATED)
+        </term>
+        <listitem>
+         <para>
+         For backwards compatibility, this is recognised as a synonym of
+          <literal>index.</literal><replaceable>set</replaceable><literal>.</literal><replaceable>name</replaceable>
+         </para>
+        </listitem>
+       </varlistentry>
+       <varlistentry><term>
          <literal>relation.</literal><replaceable>relation</replaceable>
         </term>
         <listitem>
@@ -1266,10 +1378,10 @@ int cql_transform_FILE(cql_transform_t ct,
         </term>
         <listitem>
          <para>
-          This specification defines a CQL index set for a given prefix.
+          This specification defines a CQL context set for a given prefix.
           The value on the right hand side is the URI for the set - 
           <emphasis>not</emphasis> RPN. All prefixes used in
-          qualifier patterns must be defined this way.
+          index patterns must be defined this way.
          </para>
         </listitem>
        </varlistentry>
@@ -1277,16 +1389,16 @@ int cql_transform_FILE(cql_transform_t ct,
      </para>
      <example><title>CQL to RPN mapping file</title>
       <para>
-       This simple file defines two index sets, three qualifiers and three
+       This simple file defines two context sets, three indexes and three
        relations, a position pattern and a default structure.
       </para>
       <programlisting><![CDATA[
-       set.srw    = http://www.loc.gov/zing/cql/srw-indexes/v1.0/
+       set.cql    = http://www.loc.gov/zing/cql/context-sets/cql/v1.1/
        set.dc     = http://www.loc.gov/zing/cql/dc-indexes/v1.0/
 
-       qualifier.srw.serverChoice = 1=1016
-       qualifier.dc.title         = 1=4
-       qualifier.dc.subject       = 1=21
+       index.cql.serverChoice = 1=1016
+       index.dc.title         = 1=4
+       index.dc.subject       = 1=21
   
        relation.<                 = 2=1
        relation.eq                = 2=3
@@ -1306,7 +1418,7 @@ int cql_transform_FILE(cql_transform_t ct,
        <screen>
         @attr 1=1016 @attr 2=3 @attr 4=1 @attr 3=3 @attr 6=1 "computer"
        </screen>
-       by rules <literal>qualifier.srw.serverChoice</literal>,
+       by rules <literal>index.cql.serverChoice</literal>,
        <literal>relation.scr</literal>, <literal>structure.*</literal>,
        <literal>position.any</literal>.
       </para>
@@ -1415,15 +1527,13 @@ typedef struct oident
 
    <screen>
     PROTO_Z3950
-    PROTO_SR
+    PROTO_GENERAL
    </screen>
 
    <para>
-    If you don't care about talking to SR-based implementations (few
-    exist, and they may become fewer still if and when the ISO SR and ANSI
-    Z39.50 documents are merged into a single standard), you can ignore
-    this field on incoming packages, and always set it to PROTO_Z3950
-    for outgoing packages.
+    Use <literal>PROTO_Z3950</literal> for Z39.50 Object Identifers,
+    <literal>PROTO_GENERAL</literal> for other types (such as
+    those associated with ILL).
    </para>
    <para>
 
@@ -1510,6 +1620,10 @@ typedef struct oident
 
    <para>
     again, corresponding to the specific OIDs defined by the standard.
+    Refer to the
+    <ulink url="http://lcweb.loc.gov/z3950/agency/defns/oids.html">
+     Registry of Z39.50 Object Identifiers</ulink> for the
+     whole list.
    </para>
 
    <para>
@@ -1574,6 +1688,49 @@ typedef struct oident
    </para>
 
    <para>
+    Three utility functions are provided for translating OIDs'
+    symbolic names (e.g. <literal>Usmarc</literal> into OID structures
+    (int arrays) and strings containing the OID in dotted notation
+    (e.g. <literal>1.2.840.10003.9.5.1</literal>).  They are:
+   </para>
+
+   <screen>
+    int *oid_name_to_oid(oid_class oclass, const char *name, int *oid);
+    char *oid_to_dotstring(const int *oid, char *oidbuf);
+    char *oid_name_to_dotstring(oid_class oclass, const char *name, char *oidbuf);
+   </screen>
+
+   <para>
+    <literal>oid_name_to_oid()</literal>
+     translates the specified symbolic <literal>name</literal>,
+     interpreted as being of class <literal>oclass</literal>.  (The
+     class must be specified as many symbolic names exist within
+     multiple classes - for example, <literal>Zthes</literal> is the
+     symbolic name of an attribute set, a schema and a tag-set.)  The
+     sequence of integers representing the OID is written into the
+     area <literal>oid</literal> provided by the caller; it is the
+     caller's responsibility to ensure that this area is large enough
+     to contain the translated OID.  As a convenience, the address of
+     the buffer (i.e. the value of <literal>oid</literal>) is
+     returned.
+   </para>
+   <para>
+    <literal>oid_to_dotstring()</literal>
+    Translates the int-array <literal>oid</literal> into a dotted
+    string which is written into the area <literal>oidbuf</literal>
+    supplied by the caller; it is the caller's responsibility to
+    ensure that this area is large enough.  The address of the buffer
+    is returned.
+   </para>
+   <para>
+    <literal>oid_name_to_dotstring()</literal>
+    combines the previous two functions to derive a dotted string
+    representing the OID specified by <literal>oclass</literal> and
+    <literal>name</literal>, writing it into the buffer passed as
+    <literal>oidbuf</literal> and returning its address.
+   </para>
+
+   <para>
     Finally, the module provides the following utility functions, whose
     meaning should be obvious:
    </para>
@@ -1611,7 +1768,7 @@ typedef struct oident
     release the associated memory again. For the structures describing the
     Z39.50 PDUs and related structures, it is convenient to use the
     memory-management system of the &odr; subsystem (see
-    <link linkend="odr-use">Using ODR</link>). However, in some circumstances
+    <xref linkend="odr.use"/>). However, in some circumstances
     where you might otherwise benefit from using a simple nibble memory
     management system, it may be impractical to use
     <function>odr_malloc()</function> and <function>odr_reset()</function>.