off_t

       MongoDB, Inc

       2009-present, MongoDB, Inc.

1.30.4                                            Jun 08, 2025                               BSON_READER_TELL(3)

       Tells the current position within the underlying stream.

       • reader: A bson_reader_t.

       -1 on failure, otherwise the offset within the underlying stream.

          off_t
          bson_reader_tell (bson_reader_t *reader);