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

Advanced Features 379
SIP Session Timer
If the sessionExpires parameter is set to 0, the Session-Timer mechanism is
turned off immediately in the current call-leg. Moreover, the Session-Timer
mechanism can be turned on by:
 Calling this function with non-zero sessionExpires value in the
middle of a call.
 Calling one of the Session-Timer Call-leg API functions for
refreshing the current session
(RvSipCallLegTranscSessionTimerGeneralRefresh() or
RvSipCallLegSessionTimerInviteRefresh()).
RvSipCallLegSessionTimerGetNegotiationParams()
Gets the negotiation Session Timer parameters associated with this call. These
parameters may not be equal to the Session Timer parameters of the call in the
end of the negotiation.
RvSipCallLegSessionTimerGetSessionExpiresValue()
Returns the Session-Expires value associated with the call.
RvSipCallLegSessionTimerGetMinSEValue()
Returns the Min-SE value associated with the call.
RvSipCallLegSessionTimerGetRefresherType()
Returns whether the refresher of the call is UAC or UAS. The value of refresher
type can be different from refresher preference that was requested by the
application.
RvSipCallLegSessionTimerSetAlertTime()
Allows the application to modify the time in which the
CallLegSessionTimerRefreshAlertEv() callback occurs. (The default time is
sessionExpires/2).
RvSipCallLegSessionTimerGetAlertTime()
Returns the time in which the CallLegSessionTimerRefreshAlertEv() callback
will occur after the end of the Session-Timer negotiation.