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

332 HP-UX C SIP Stack Programmer’s Guide
SIP Stack Implementation
 IP addresses list—the result of an A/AAAA query applied on
the first element of the Host list. After the A/AAAA query is
made, the first element in the Host list is moved to the used host
element member of the DNS list.
In addition, the DNS List object holds the host record used to resolve the IP and
the SRV record used to resolve the port. Note that the SRV list, Host list and
used SRV are only kept if the SIP Stack was compiled with the Enhanced DNS
feature.
The records in each list are sorted by their priorities. Figure 15-2 illustrates a
DNS List object.
Figure 15-2 DNS List Object
IP Element IP Element IP Element IP Element
Host Element Host ElementHost Element Host Element
SRV Element SRV Element SRV Element SRV Element
DNS List Object
Used Host
Element
Used SRV
Element
Only exists if SIP Stack compied
with Enhanced DNS features
Always exists
ENUM
Element