Functions
DIFFUSION_FETCH_REQUEST_T *	diffusion_fetch_request_init (SESSION_T *session)
	Creates an unconfigured fetch request.

DIFFUSION_FETCH_REQUEST_T *	diffusion_fetch_request_dup (const DIFFUSION_FETCH_REQUEST_T *fetch_request)
	Create a duplicate (copy) of an existing `DIFFUSION_FETCH_REQUEST_T`.

void	diffusion_fetch_request_free (DIFFUSION_FETCH_REQUEST_T *fetch_request)
	Free a memory allocated `DIFFUSION_FETCH_REQUEST_T`

TOPIC_HANDLER_T	subscribe (SESSION_T *session, const SUBSCRIPTION_PARAMS_T params)
	Request subscription to topic.

TOPIC_HANDLER_T	diffusion_subscribe_with_scope (SESSION_T session, const char selection_scope, const SUBSCRIPTION_PARAMS_T params, DIFFUSION_API_ERROR *api_error)
	Request subscription to topics using a scope selection.

void	unsubscribe (SESSION_T *session, const UNSUBSCRIPTION_PARAMS_T params)
	Unsubscribe from one or more topics.

bool	diffusion_unsubscribe_with_scope (SESSION_T session, const char selection_scope, const UNSUBSCRIPTION_PARAMS_T params, DIFFUSION_API_ERROR *api_error)
	Unsubscribe from topics using a selection scope.

bool	diffusion_unsubscribe_all_scopes (SESSION_T session, const UNSUBSCRIPTION_ALL_SCOPES_PARAMS_T params, DIFFUSION_API_ERROR api_error)
	Unsubscribe topics from all topic selection scopes.

void	notify_subscription_register (SESSION_T *session, const NOTIFY_SUBSCRIPTION_PARAMS_T params)
	Register to receive subscription notifications.

void	notify_unsubscription_register (SESSION_T *session, const NOTIFY_UNSUBSCRIPTION_PARAMS_T params)
	Register to receive unsubscription notifications.

Detailed Description

Function Documentation

◆ diffusion_fetch_request_dup()

DIFFUSION_FETCH_REQUEST_T * diffusion_fetch_request_dup ( const DIFFUSION_FETCH_REQUEST_T * fetch_request )

Create a duplicate (copy) of an existing DIFFUSION_FETCH_REQUEST_T.

diffusion_fetch_request_free should be called on this pointer when no longer needed.

Parameters

fetch_request fetch request to be duplicated

Returns: a copy of the provided fetch request. NULL, if the fetch request is NULL.

◆ diffusion_fetch_request_free()

void diffusion_fetch_request_free ( DIFFUSION_FETCH_REQUEST_T * fetch_request )

Free a memory allocated DIFFUSION_FETCH_REQUEST_T

Parameters

fetch_request The fetch request to be freed

◆ diffusion_fetch_request_init()

DIFFUSION_FETCH_REQUEST_T * diffusion_fetch_request_init ( SESSION_T * session )

Creates an unconfigured fetch request.

Parameters

session The session handle. If NULL, the function returns NULL.

Returns: a new unconfigured fetch request

◆ diffusion_subscribe_with_scope()

TOPIC_HANDLER_T diffusion_subscribe_with_scope	(	SESSION_T *	session,
		const char *	selection_scope,
		const SUBSCRIPTION_PARAMS_T	params,
		DIFFUSION_API_ERROR *	api_error
	)

Request subscription to topics using a scope selection.

The session will become subscribed to each existing topic matching the selector unless the session is already subscribed to the topic, or the session does not have READ_TOPIC permission for the topic path. For each topic to which the session becomes subscribed, a subscription notification and initial value (if any) will be delivered to registered value streams.

The subscription request is also retained at the server and the session will be automatically subscribed to newly created topics that match the selector (unless a subsequent unsubscription cancels the request).

Parameters

session	The session handle. If NULL, this function returns immediately.
scope	Specifies the scope of the selection.
params	Parameters describing the subscription request and callbacks handlers which may be invoked in response.
api_error	Populated on API error. Can be NULL.

Returns: true if the operation was successful, false otherwise. In this case, if a non-NULL api_error pointer has been provided, this will be populated with the error information and should be freed with diffusion_api_error_free.

Since: 6.12

◆ diffusion_unsubscribe_all_scopes()

bool diffusion_unsubscribe_all_scopes	(	SESSION_T *	session,
		const UNSUBSCRIPTION_ALL_SCOPES_PARAMS_T	params,
		DIFFUSION_API_ERROR *	api_error
	)

Unsubscribe topics from all topic selection scopes.

This can be used at any time whilst connected to reduce the set of topics to which the session is subscribed or negate earlier subscription requests and will apply to all scopes in use.

Parameters

session	The session handle. If NULL, this function returns immediately.
params	Parameters describing the unsubscription request and callback handlers which may be invoked in response.
api_error	Populated on API error. Can be NULL.

Returns: true if the operation was successful, false otherwise. In this case, if a non-NULL api_error pointer has been provided, this will be populated with the error information and should be freed with diffusion_api_error_free.

Since: 6.12

◆ diffusion_unsubscribe_with_scope()

bool diffusion_unsubscribe_with_scope	(	SESSION_T *	session,
		const char *	selection_scope,
		const UNSUBSCRIPTION_PARAMS_T	params,
		DIFFUSION_API_ERROR *	api_error
	)

Unsubscribe from topics using a selection scope.

This can be used at any time whilst connected to reduce the set of topics to which the session is subscribed or negate earlier subscription requests.

Parameters

session	The session handle. If NULL, this function returns immediately.
scope	Specifies the scope of the selection.
params	Parameters describing the unsubscription request and callback handlers which may be invoked in response.
api_error	Populated on API error. Can be NULL.

Returns: true if the operation was successful, false otherwise. In this case, if a non-NULL api_error pointer has been provided, this will be populated with the error information and should be freed with diffusion_api_error_free.

Since: 6.12

◆ notify_subscription_register()

void notify_subscription_register	(	SESSION_T *	session,
		const NOTIFY_SUBSCRIPTION_PARAMS_T	params
	)

Register to receive subscription notifications.

This function should be called by the application to register to receive notifications that it has been subscribed to a topic.

Parameters

session	The current session. If NULL, this function returns immediately.
params	Callbacks and other parameters. `on_notify_subscription` should be set to receive notifications.

◆ notify_unsubscription_register()

void notify_unsubscription_register	(	SESSION_T *	session,
		const NOTIFY_UNSUBSCRIPTION_PARAMS_T	params
	)

Register to receive unsubscription notifications.

This function should be called by the application to receive notifications that it has been unsubscribed to a topic.

Parameters

session	The current session. If NULL, this function returns immediately.
params	Callbacks and other parameters. `on_notify_unsubscription` should be set to receive notifications.

◆ subscribe()

TOPIC_HANDLER_T subscribe	(	SESSION_T *	session,
		const SUBSCRIPTION_PARAMS_T	params
	)

Request subscription to topic.

This is equivalent to calling diffusion_subscribe_with_scope specifying DEFAULT_SELECTION_SCOPE.

Parameters

session	The session handle. If NULL, the function returns immediately.
params	Parameters describing the subscription request and callbacks handlers which may be invoked in response.

Returns: Previous topic handler if replacing, else NULL.

◆ unsubscribe()

void unsubscribe	(	SESSION_T *	session,
		const UNSUBSCRIPTION_PARAMS_T	params
	)

Unsubscribe from one or more topics.

This is equivalent to calling diffusion_unsubscribe_with_scope specifying DEFAULT_SELECTION_SCOPE.

Parameters

session	The session handle. If NULL, this function returns immediately.
params	Parameters describing the unsubscription request and callback handlers which may be invoked in response.

Functions

Detailed Description

Function Documentation

◆ diffusion_fetch_request_dup()

◆ diffusion_fetch_request_free()

◆ diffusion_fetch_request_init()

◆ diffusion_subscribe_with_scope()

◆ diffusion_unsubscribe_all_scopes()

◆ diffusion_unsubscribe_with_scope()

◆ notify_subscription_register()

◆ notify_unsubscription_register()

◆ subscribe()

◆ unsubscribe()