Distributed Name Service (DNS) Management Programming Manual

Using SPI to Build Commands and Decode Responses
SPI Programming Considerations for DNS
46958 Tandem Computers Incorporated 3–5
Event Numbers All event messages contain a header token identifying the event by number. This
event number, in combination with the subsystem ID header token, uniquely identifies
the kind of event being reported. Event numbers for event messages defined by DNS
are identified in programs by symbolic names of the form ZDNS-EVT- name , where
name gives a brief identification of the event being reported.
In these event messages, the event-number header token (ZEMS-TKN-EVENTNUMBER)
can assume any one of the set of event numbers for DNS. DNS event numbers and
messages are described in Section 6.
Subjects of Event
Messages
DNS always assigns the ZDNS-TKN-SUBJECT token as the subject of an event
message. Depending on the value of ZDNS-TKN-SUBJECT, DNS generates additional
subject tokens. Subjects of DNS event messages can pertain to the DNS subsystem as a
whole, a DNS name manager, a name exporter, a DNS function, or other elements. All
DNS subject tokens are listed in Section 6.
Other Tokens Commands, responses, and event messages for DNS, like those for other subsystems,
also include other tokens providing further information. For information about such
tokens, their types, and the values that are predefined for some of them, refer to the
Distributed Systems Management (DSM) Programming Manual.
Data Lists and Error Lists Responses from the DNS subsystem can contain data lists and error lists, as described
in the Distributed Systems Management (DSM) Programming Manual. The response
buffer many contain one or more data lists if the ZSPI-TKN-MAXRESP is not zero.
The response buffer many contain one or more error lists if the ZSPI-TKN-RETCODE
has a nonzero value.
Using SPI to Build
Commands and
Decode Responses
The Distributed Systems Management (DSM) Programming Manual provides information
on how to build and send a command message and how to receive and decode a
response message. Refer to that manual for details.
The following subsections provide a summary of the steps your application must take
to perform each of these tasks, followed by DNS-specific programming considerations.