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

Working with Transactions 97
Transaction API
RvSipTransactionRespond()
Use this function to send a provisional or final response to a transaction that
received an incoming request. You can use this function with any response code
and reason phrase.
RvSipTransactionRespondReliable()
Use this function in the INVITE-REQUEST-RECEIVED state to send a reliable
provisional response. You can use this function with response codes between
101 and 199 with any reason phrase. After sending the reliable provisional
response, the transaction assumes the
INVITE_RELIABLE_PROVISIONAL_SENT state. You can only send reliable
provisional responses on Invite transactions. This function should be used only
if the supported header list of the SIP Stack configuration includes the 100rel
option tag.
RvSipTransactionCancel()
Use this function to cancel a transaction that reached the PROCEEDING state.
You can use this function only on INVITE client transactions. You supply this
function with the transaction you wish to cancel. A CANCEL transaction will
be created and a CANCEL request will be sent to the remote party. The
application is informed of the new CANCEL transaction using the
RvSipTransactionInternalCreated() callback function.
RvSipTransactionAck()
Use this function to send an ACK request on a given INVITE transaction. This
function can only be called on INVITE client transactions that reached the
INVITE_FINAL_RESPONSE_RECEIVED state, after receiving a non-2xx
final response.
Remark: ACK on a 2xx response should be sent as a stand-alone message using
the Transmitter API.
RvSipTransactionTerminate()
Use this function to cause an immediate shut-down of the transaction. A
transaction is a self-terminated object. The termination of a transaction depends
on the transaction state and timer configurations. By using this function, the
application can terminate a transaction before its normal termination. After
calling this function, the transaction will assume the TERMINATED state.