``opts`` may be NULL or a BSON document with additional command options:

* ``batchSize``: An ``int32`` representing number of documents requested to be returned on each call to :symbol:`mongoc_change_stream_next`
* ``resumeAfter``: A ``Document`` representing the logical starting point of the change stream. The ``_id`` field  of any change received from a change stream can be used here
* ``startAtOperationTime``: A ``Timestamp``. The change stream only provides changes that occurred at or after the specified timestamp. Any command run against the server will return an operation time that can be used here.
* ``maxAwaitTimeMS``: An ``int64`` representing the maximum amount of time a call to :symbol:`mongoc_change_stream_next` will block waiting for data
* ``fullDocument``: A UTF-8 string. Set this option to "updateLookup" to direct the change stream cursor to lookup the most current majority-committed version of the document associated to an update change stream event.
