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

Working with Call-legs (Dialogs) 47
Call-leg API
RvSipCallLegCancel()
Sends CANCEL on an outgoing INVITE message if the final response was not
yet received. This function can be used in one of the following call-leg states:
 PROCEEDING
 PROCEEDING_TIMEOUT
It can also be used in one of the following re-INVITE states:
 REINVITE_PROCEEDING
 REINVITE_PROCEEDING_TIMEOUT
RvSipCallLegAck()
When the SIP Stack is configured to work in a manual ACK mode, the call-leg
will not send an ACK message after receiving an INVITE 2xx response. After
receiving the 2xx response, the call-leg will assume the REMOTE_ACCEPTED
state. The application must use the RvSipCallLegAck() function to trigger the
call-leg to send the ACK.
RvSipCallLegProvisionalResponse()
You can use RvSipCallLegProvisionalResponse() to send a provisional
response before sending a final response. For example, when the call-leg is in
the OFFERING state, you can use this function to send a 100 Trying or a
180 Ringing provisional response.
RvSipCallLegAuthenticate()
If a call-leg receives a 401 or 407 response indicating that a request was
unauthenticated by the server or Proxy, the call-leg assumes the
UNAUTHENTICATED state. You can use RvSipCallLegAuthenticate() in the
UNAUTHENTICATED state to re-send the request with authentication
information. If you do not wish to proceed with the authentication process, you
should terminate the call-leg.
Note This function should not be used to authenticate a re-INVITE or general
request inside a call-leg.