These operations can be performed on both protocols and sessions.
GETMYHOST, GETMYHOSTCOUNT
When used on a protocol, GETMYHOST asks for all possible host addresses for the local host. When used on a session,GETMYHOST asks for the local host addresses actually being used on the connection. If the buffer is too small for all of the hosts, GETMYHOST will write as many hosts as the buffer allows (
GETMYHOST with a buffer large enough to hold one host will return the most common or default host). GETMYHOSTCOUNT asks for the number of hosts which could be returned by GETMYHOST.
GETMAXPACKET, GETOPTPACKET
Treats the buffer as a pointer to an integer and sets it to the length of the longest message that the protocol can deliver (GETMAXPACKET) or the length of the longest message that can be delivered without fragmentation ( GETOPTPACKET). A protocol typically implements this operation by querying its lower protocol and then subtracting its header length.
Although GETMAXPACKET and GETOPTPACKET can be performed on protocols, it is preferable to use them on sessions, since different sessions of the same protocol may return different values.
RESOLVE, RRESOLVE
These operations map high-level addresses into low-level addresses ( RESOLVE) and vice versa ( RRESOLVE).