+/* Get the current version of the metadata cache (after a get_next). */
+#define RING_BUFFER_GET_METADATA_VERSION _IOR(0xF6, 0x0D, uint64_t)
+/*
+ * Get a snapshot of the current ring buffer producer and consumer positions,
+ * regardless of whether or not the two positions are contained within the same
+ * sub-buffer.
+ */
+#define RING_BUFFER_SNAPSHOT_SAMPLE_POSITIONS _IO(0xF6, 0x0E)