- <para>Sends Item Update Request. This command sends a "minimal"
- PDU Update to the target supplying the last received record from
- the target.
- If no record has been received from the target this command is ignored
- and nothing is sent to the target.
+ <para>Sends Item Update Request. The <replaceable>action</replaceable>
+ argument must be the action type: one of <literal>insert</literal>,
+ <literal>replace</literal>, <literal>delete</literal> and
+ <literal>update</literal>. The second argument,
+ <replaceable>recid</replaceable>, is the
+ record identifier (any string). Third argument which is optional is
+ the record document for the request. If doc is preceded with
+ "<", then the following characters are treated as a filename
+ with the records to be updated. Otherwise doc is treated as
+ a document itself. The doc may also be quited in double quotes.
+ If doc is omitted, the last received record (as part of present
+ response or piggybacked search response) is used for the update.