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

344 HP-UX C SIP Stack Programmer’s Guide
Resolver Entities
RVSIP_RESOLVER_MODE_UNDEFINED
Represents no-resolution mode.
RVSIP_RESOLVER_MODE_FIND_TRANSPORT_BY_NAPTR
Instructs the resolver to try obtaining NAPTR records for a domain. The
resolver will use the protocol field of the NAPTR record to determine the
transport, for example, getting the available transports for hp.com. The result
will be a list of SRV record pointers.
RVSIP_RESOLVER_MODE_FIND_TRANSPORT_BY_3WAY_SRV
Instructs the resolver to try finding a transport for a domain by applying SRV
queries of <_service>._<protocol>.<domain>, until the resolver receives a
successful answer. For example, the resolution of sip:[e-mail] will include
queries in the sip._<protocol>.hp.com format, first trying UDP, then TCP, and
finally TLS. If the resolver gets a positive answer, it will stop querying, and as a
result, provide a host pointer and a port number.
RVSIP_RESOLVER_MODE_FIND_HOSTPORT_BY_SRV_STRING
Instructs the resolver to send one SRV query with the string supplied and to save
the host and port retrieved in the answer in the DNS list, for example, trying to
get the host and port for _sip._udp.hp.com.
RVSIP_RESOLVER_MODE_FIND_HOSTPORT_BY_TRANSPORT
Instructs the resolver to create one service._<protocol>.domain query string and
try sending an SRV query for it. The host and port retrieved in the answer will
be stored in the DNS list. For example, trying to get the TCP/pres SRV record
for hp.com will send a _pres._udp.hp.com SRV query and will result in a host
pointer and a port number.
RVSIP_RESOLVER_MODE_FIND_IP_BY_HOST
Instructs the resolver to try finding the IP of a specific host. The resolver will try
both IPv4 and IPv6 (using A and AAAA queries respectively). For example,
when trying to get the IP for host1.hp.com, the result will be an IP address.