This function visits all the direct children of the given cursor,
invoking the given \p visitor function with the cursors of each
visited child. The traversal may be recursive, if the visitor returns
\c CXChildVisit_Recurse. The traversal may also be ended prematurely, if
the visitor returns \c CXChildVisit_Break.
\param parent the cursor whose child may be visited. All kinds of
cursors can be visited, including invalid cursors (which, by
definition, have no children).
\param visitor the visitor function that will be invoked for each
child of \p parent.
\param client_data pointer data supplied by the client, which will
be passed to the visitor each time it is invoked.
\returns a non-zero value if the traversal was terminated
prematurely by the visitor returning \c CXChildVisit_Break.
\brief Visit the children of a particular cursor.
This function visits all the direct children of the given cursor, invoking the given \p visitor function with the cursors of each visited child. The traversal may be recursive, if the visitor returns \c CXChildVisit_Recurse. The traversal may also be ended prematurely, if the visitor returns \c CXChildVisit_Break.
\param parent the cursor whose child may be visited. All kinds of cursors can be visited, including invalid cursors (which, by definition, have no children).
\param visitor the visitor function that will be invoked for each child of \p parent.
\param client_data pointer data supplied by the client, which will be passed to the visitor each time it is invoked.
\returns a non-zero value if the traversal was terminated prematurely by the visitor returning \c CXChildVisit_Break.