+ struct lttng_session *session, int is_open);
+
+/*
+ * Machine interface: open a domains element.
+ *
+ * writer An instance of a machine interface writer.
+ *
+ * Returns zero if the element's value could be written.
+ * Negative values indicate an error.
+ */
+int mi_lttng_domains_open(struct mi_writer *writer);
+
+/*
+ * Machine interface of struct domain.
+ *
+ * writer An instance of a machine interface writer.
+ * domain An instance of a domain.
+ *
+ * is_open Defines whether or not the session element shall be closed.
+ * This should be used carefully and the client
+ * must close the domain element.
+ * Use case: nested addition information on a domain
+ * ex: channel event.
+ *
+ * Returns zero if the element's value could be written.
+ * Negative values indicate an error.
+ */
+int mi_lttng_domain(struct mi_writer *writer,
+ struct lttng_domain *domain, int is_open);
+
+/*
+ * Machine interface: open a channels element.
+ *
+ * writer An instance of a machine interface writer.
+ *
+ * Returns zero if the element's value could be written.
+ * Negative values indicate an error.
+ */
+int mi_lttng_channels_open(struct mi_writer *writer);
+
+/*
+ * Machine interface of struct channel.
+ *
+ * writer An instance of a machine interface writer.
+ * channel An instance of a channel.
+ *
+ * is_open Defines whether or not the session element shall be closed.
+ * This should be used carefully and the client
+ * must close the channel element.
+ * Use case: nested addition information on a channel.
+ * ex: channel event.
+ *
+ * Returns zero if the element's value could be written.
+ * Negative values indicate an error.
+ */
+int mi_lttng_channel(struct mi_writer *writer,
+ struct lttng_channel *channel, int is_open);
+
+/*
+ * Machine interface of struct channel_attr.
+ *
+ * writer An instance of a machine interface writer.
+ * attr An instance of a channel_attr struct.
+ *
+ * Returns zero if the element's value could be written.
+ * Negative values indicate an error.
+ */
+int mi_lttng_channel_attr(struct mi_writer *writer,
+ struct lttng_channel_attr *attr);
+
+/*
+* Machine interface for event common attributes.
+*
+* writer An instance of a mi writer.
+* event single trace event.
+*
+* The common attribute are:
+* - mi event element
+* - event name
+* - event type
+* - enabled tag
+* - event filter
+*
+* Returns zero if the element's value could be written.
+* Negative values indicate an error.
+*/
+int mi_lttng_event_common_attributes(struct mi_writer *writer,
+ struct lttng_event *event);
+
+/*
+ * Machine interface for kernel tracepoint event with a loglevel.
+ *
+ * writer An instance of a mi writer.
+ * event single trace event.
+ *
+ * Returns zero if the element's value could be written.
+ * Negative values indicate an error.
+ */
+int mi_lttng_event_tracepoint_loglevel(struct mi_writer *writer,
+ struct lttng_event *event);
+
+/*
+ * Machine interface for kernel tracepoint event with no loglevel.
+ *
+ * writer An instance of a mi writer.
+ * event single trace event.
+ *
+ * Returns zero if the element's value could be written.
+ * Negative values indicate an error.
+ */
+int mi_lttng_event_tracepoint_no_loglevel(struct mi_writer *writer,
+ struct lttng_event *event);
+
+/*
+ * Machine interface for kernel function and probe event.
+ *
+ * writer An instance of a mi writer.
+ * event single trace event.
+ *
+ * Returns zero if the element's value could be written.
+ * Negative values indicate an error.
+ */
+int mi_lttng_event_function_probe(struct mi_writer *writer,
+ struct lttng_event *event);
+
+/*
+ * Machine interface for kernel function entry event.
+ *
+ * writer An instance of a mi writer.
+ * event single trace event.
+ *
+ * Returns zero if the element's value could be written.
+ * Negative values indicate an error.
+ */
+int mi_lttng_event_function_entry(struct mi_writer *writer,
+ struct lttng_event *event);
+
+/*
+ * Machine interface: open an events element.
+ *
+ * writer An instance of a machine interface writer.
+ *
+ * Returns zero if the element's value could be written.
+ * Negative values indicate an error.
+ */
+int mi_lttng_events_open(struct mi_writer *writer);
+
+/*
+ * Machine interface for printing an event.
+ * The trace event type currently supported are:
+ * TRACEPOINT,
+ * PROBE,
+ * FUNCTION,
+ * FUNCTION_ENTRY,
+ * SYSCALL
+ *
+ * writer An instance of a mi writer.
+ * event single trace event.
+ * is_open Defines whether or not the session element shall be closed.
+ * This should be used carefully and the client
+ * must close the event element.
+ * Use case: nested additional information
+ *
+ * Returns zero if the element's value could be written.
+ * Negative values indicate an error.
+ */
+int mi_lttng_event(struct mi_writer *writer, struct lttng_event *event,
+ int is_open);
+
+/*
+ * Machine interface for struct lttng_event_field.
+ *
+ * writer An instance of a mi writer.
+ * field An event_field instance.
+ *
+ * Returns zero if the element's value could be written.
+ * Negative values indicate an error.
+ */
+int mi_lttng_event_field(struct mi_writer *writer,
+ struct lttng_event_field *field);
+
+/*
+ * Machine interface: open a event_fields element.
+ *
+ * writer An instance of a machine interface writer.
+ *
+ * Returns zero if the element could be written.
+ * Negative values indicate an error.
+ */
+int mi_lttng_event_fields_open(struct mi_writer *writer);
+
+/*
+ * Machine interface: open a PIDs element.
+ *
+ * writer An instance of a machine interface writer.
+ *
+ * Returns zero if the element's value could be written.
+ * Negative values indicate an error.
+ */
+int mi_lttng_pids_open(struct mi_writer *writer);
+
+/*
+ * Machine interface of a PID.
+ *
+ * writer An instance of a machine interface writer.
+ * pid A PID.
+ *
+ * is_open Defines whether or not the session element shall be closed.
+ * This should be used carefully and the client
+ * must close the pid element.
+ * Use case: nested addition information on a domain
+ * ex: channel event.
+ *
+ * Returns zero if the element's value could be written.
+ * Negative values indicate an error.
+ */
+int mi_lttng_pid(struct mi_writer *writer, pid_t pid , const char *cmdline,
+ int is_open);
+
+/*
+ * Machine interface for struct lttng_calibrate.
+ *
+ * writer An instance of a machine interface writer.
+ *
+ * calibrate A lttng_calibrate instance.
+ *
+ * Returns zero if the element's value could be written.
+ * Negative values indicate an error.
+ */
+int mi_lttng_calibrate(struct mi_writer *writer,
+ struct lttng_calibrate *calibrate);
+
+/*
+ * Machine interface of a context.
+ *
+ * writer An instance of a machine interface writer
+ *
+ * context An instance of a lttng_event_context
+ *
+ * is_open Define if we close the context element
+ * This should be used carefully and the client
+ * need to close the context element.
+ * 0-> False
+ * 1-> True
+ * Returns zero if the element's value could be written.
+ * Negative values indicate an error.
+ */
+int mi_lttng_context(struct mi_writer *writer,
+ struct lttng_event_context *context, int is_open);
+
+/*
+ * Machine interface of a perf_counter_context.
+ *
+ * writer An instance of a machine interface writer
+ *
+ * contest An instance of a lttng_event_perf_counter_ctx
+ *
+ * Returns zero if the element's value could be written.
+ * Negative values indicate an error.
+ */
+int mi_lttng_perf_counter_context(struct mi_writer *writer,
+ struct lttng_event_perf_counter_ctx *perf_context);