User`s guide

Dialogic
®
System Release 6.0 PCI for Windows
®
Release Update, Rev 62 — January 30, 2008 211
Dialogic Corporation
1.51.4.4 gc_InvokeXfer( ) Variances for IP
This function is only available if the call transfer supplementary service was enabled via
the sup_serv_mask field in the IP_VIRTBOARD structure when the board device was
started.
Variance for SIP
The application at party A may optionally be notified by a
GCEV_INVOKE_XFER_ACCEPTED event that the transfer request has been accepted
by the remote party to which it was sent. (This event has no equivalent in H.450.2.) This
event is optional, and is disabled by default. The event may be enabled and disabled on a
per-line-device basis via the gc_SetConfigData( ) function as shown in the following code
example.
//enable GCEV_INVOKE_XFER_ACCEPTED event for SIP call transfer
GC_PARM_BLK *t_pParmBlk = NULL;
long request_id;
gc_util_insert_parm_val(&t_parmBlkl, GCSET_CALLEVENT_MSK, GCACT_ADDMSK,
sizeof(long), GCMSK_INVOKE_XFER_ACCEPTED);
gc_SetConfigData(GCTGT_GCLIB_CHAN,ldev,t_pParmBlk,0,GCUPDATE_IMMEDIATE,&request_id,EV_SYNC);
gc_util_delete_parm_blk(t_pParmBlk)
The specific meaning of the GCEV_INVOKE_XFER termination event for successful
transfers is dependant on the application and the transfer scenario(s) it uses. The possible
outcomes when Global Call is used by all parties include the following:
• If party A drops the primary call in unattended transfers before the transfer completes,
party A does not receive any GCEV_INVOKE_XFER event at all.
• If party B drops the primary call in unattended transfers before the transfer completes,
party A receives a GCEV_INVOKE_XFER event that only signifies that party B has
sent INVITE to party C.
• For attended transfers or unattended transfers where the primary call is maintained
during the transfer, party A receives a GCEV_INVOKE_XFER event which indicates
that the transferred call was actually connected between party B and party C.
Table 3 identifies the protocol-specific variances in parameters for gc_InvokeXfer( ).
Table 3. gc_InvokeXfer( ) Supported Parameters for SIP
Parameter Meaning
crn The CRN of the call between party A and the remote party receiving the transfer request.
This is the primary call in an unattended (blind) call transfer, but may be either call for an
attended (supervised) transfer.
extracrn For an attended (supervised) call transfer, the CRN of the call between party A and the
remote party not receiving the transfer request (i.e. the call not specified in the crn
parameter).
For unattended (blind) call transfers, must be zero.