Distributed Name Service (DNS) Management Programming Manual

3 SPI Programming
Considerations for DNS
46958 Tandem Computers Incorporated 3–1
Once your subsystem and EMS processes are running and your management
application has established communication with them, the main business of your
management application is to format and send commands, decode responses and act
on the results, and interpret event messages and act on their information.
The Distributed Systems Management (DSM) Programming Manual provides general
instructions for formatting commands and decoding responses and event messages for
subsystems such as DNS. This section provides some summary information and
discusses SPI programming considerations that are specific to the DNS subsystem.
Definition Files The commands, responses, and event messages sent to and received from the DNS
subsystem are made up of items called tokens. Each token contains a particular piece
of information, such as a command parameter or an item of information about an
event. Tokens can be single values or structures consisting of several values. Some
tokens, called header tokens, are present in every command and response, and in
every event message.
Tokens and related data items for commands, responses, and event messages must be
declared in your management applications. However, Tandem provides these
declarations for you in definition files. A set of definition files is provided as part of
each Tandem subsystem that supports DSM; a few other Tandem software
components (such as SPI and EMS) also provide definition files. Each such software
component includes five definition files, in the following languages:
Transaction Application Language (TAL)
Tandem 1985 standard COBOL (COBOL85)
The C language
Tandem Advanced Command Language (TACL)
Data Definition Language (DDL)
The DDL file is the source from which the other four definition files are derived.
To be able to use the data declarations defined by a particular Tandem software
component, your application must incorporate the appropriate programming-
language definition file associated with that software component. The declarations in
a COBOL85 definition file are grouped into sections to enable COBOL85 programs to
declare multiple copies of structures in the definition file. TAL and C programs can
source in either the entire definition file or just the sections they need. TACL always
loads the entire definition file. For further information about how definition files are
used by an application, refer to the Distributed Systems Management (DSM)
Programming Manual.