+ * This telemetry callback is used when registering a telemetry command.
+ * It handles getting and formatting information to be returned to telemetry
+ * when requested.
+ *
+ * @param cmd
+ * The cmd that was requested by the client.
+ * @param params
+ * Contains data required by the callback function.
+ * @param info
+ * The information to be returned to the caller.
+ *
+ * @return
+ * Length of buffer used on success.
+ * @return
+ * Negative integer on error.
+ */
+typedef int (*telemetry_cb)(const char *cmd, const char *params,
+ struct rte_tel_data *info);
+
+/**
+ * Used for handling data received over a telemetry socket.
+ *
+ * @param sock_id
+ * ID for the socket to be used by the handler.
+ *
+ * @return
+ * Void.
+ */
+typedef void * (*handler)(void *sock_id);
+
+/**
+ * Used when registering a command and callback function with telemetry.
+ *
+ * @param cmd
+ * The command to register with telemetry.
+ * @param fn
+ * Callback function to be called when the command is requested.
+ * @param help
+ * Help text for the command.
+ *
+ * @return
+ * 0 on success.
+ * @return
+ * -EINVAL for invalid parameters failure.
+ * @return
+ * -ENOENT if max callbacks limit has been reached.
+ */
+__rte_experimental
+int
+rte_telemetry_register_cmd(const char *cmd, telemetry_cb fn, const char *help);
+
+/**
+ * @internal
+ * Initialize Telemetry.