DOCS-6720 remove legacy C++ driver example

source/tutorial/create-tailable-cursor.txt

@@ -55,119 +55,3 @@ Consider the following behaviors related to tailable cursors:
 
 See your :doc:`driver documentation </applications/drivers>` for the
 driver-specific method to specify the tailable cursor.
-
-C++ Example
------------
-
-The ``tail`` function uses a tailable cursor to output the results from
-a query to a capped collection:
-
-- The function handles the case of the dead cursor by having the query
-  be inside a loop.
-
-- To periodically check for new data, the ``cursor->more()`` statement
-  is also inside a loop.
-
-.. code-block:: cpp
-
-   #include "client/dbclient.h"
-
-   using namespace mongo;
-
-   /*
-    * Example of a tailable cursor.
-    * The function "tails" the capped collection (ns) and output elements as they are added.
-    * The function also handles the possibility of a dead cursor by tracking the field 'insertDate'.
-    * New documents are added with increasing values of 'insertDate'.
-    */
-
-   void tail(DBClientBase& conn, const char *ns) {
-
-       BSONElement lastValue = minKey.firstElement();
-
-       Query query = Query().hint( BSON( "$natural" << 1 ) );
-
-       while ( 1 ) {
-           auto_ptr<DBClientCursor> c =
-               conn.query(ns, query, 0, 0, 0,
-                          QueryOption_CursorTailable | QueryOption_AwaitData );
-
-           while ( 1 ) {
-               if ( !c->more() ) {
-
-                   if ( c->isDead() ) {
-                       break;
-                   }
-
-                   continue;
-               }
-
-               BSONObj o = c->next();
-               lastValue = o["insertDate"];
-               cout << o.toString() << endl;
-           }
-
-           query = QUERY( "insertDate" << GT << lastValue ).hint( BSON( "$natural" << 1 ) );
-       }
-   }
-
-The ``tail`` function performs the following actions:
-
-- Initialize the ``lastValue`` variable, which tracks the last
-  accessed value. The function will use the ``lastValue`` if the
-  cursor becomes *invalid* and ``tail`` needs to restart the
-  query. Use :method:`~cursor.hint()` to ensure that the query uses
-  the :operator:`$natural` order.
-
-- In an outer ``while(1)`` loop,
-
-  - Query the capped collection and return a tailable cursor that
-    blocks for several seconds waiting for new documents
-
-    .. code-block:: cpp
-
-       auto_ptr<DBClientCursor> c =
-            conn.query(ns, query, 0, 0, 0,
-                       QueryOption_CursorTailable | QueryOption_AwaitData );
-
-    - Specify the capped collection using ``ns`` as an argument
-      to the function.
-
-    - Set the ``QueryOption_CursorTailable`` option to create a
-      tailable cursor.
-
-    - Set the ``QueryOption_AwaitData`` option so that the returned
-      cursor blocks for a few seconds to wait for data.
-
-  - In an inner ``while (1)`` loop, read the documents from the cursor:
-
-    - If the cursor has no more documents and is not invalid, loop the
-      inner ``while`` loop to recheck for more documents.
-
-    - If the cursor has no more documents and is dead, break the inner
-      ``while`` loop.
-
-    - If the cursor has documents:
-
-      - output the document,
-
-      - update the ``lastValue`` value,
-
-      - and loop the inner ``while (1)`` loop to recheck for more
-        documents.
-
-  - If the logic breaks out of the inner ``while (1)`` loop and the
-    cursor is invalid:
-
-    - Use the ``lastValue`` value to create a new query condition that
-      matches documents added after the ``lastValue``. Explicitly
-      ensure ``$natural`` order with the ``hint()`` method:
-
-      .. code-block:: cpp
-
-         query = QUERY( "insertDate" << GT << lastValue ).hint( BSON( "$natural" << 1 ) );
-
-    - Loop through the outer ``while (1)`` loop to re-query with the new query
-      condition and repeat.
-
-.. seealso:: `Detailed blog post on tailable cursor <http://shtylman.com/post/the-tail-of-mongodb>`_