HP-UX C SIP Stack Programmer's Guide (Novembery 2007)

Event Notification 243
Notification Control API
RvSipSubsExpirationAlertEv()
Alerts the application that the subscription timer is about to expire. The
application should use this callback to send a refresh SUBSCRIBE request.
The time interval before expiration for this callback to be called is set with the
“SubscriptionAlertTime” configuration parameter or with the
RvSipSubsSetAlertTimer() function for a specific subscription.
Note This event function will not be called when working in Auto-refresh mode.
RvSipSubsMsgToSendEv()
The subscription calls this event whenever a subscription-related message is
ready to be sent. You can use this callback for changing or examining a message
before it is sent to the remote party.
RvSipSubsMsgReceivedEv()
The subscription calls this event whenever a subscription-related message has
been received and is about to be processed. You can use this callback to examine
incoming messages.
RvSipSubsNotifyCreatedEv()
Indicates that a new notification was created and exchanges handles with the
application.
RvSipSubsNotifyEv()
Notifies the application of a notify status. Through this function you receive
indications of SIP notify status and the associated reason. For example, upon
receipt of a NOTIFY-RCVD status, your application may decide whether to
accept or reject the NOTIFY request.
A subscriber application gets the received NOTIFY request message in this
event, and its related notification handle. At this callback, the application can get
all needed information from the NOTIFY request message. The message will be
destructed after calling this callback.
A notifier application gets the received NOTIFY response message that was
received for a NOTIFY request. At the end of this callback, the Stack
notification is destructed.