Safeguard Management Programming Manual (G06.24+, H06.03+)

Safeguard Management Programming Manual—422086-012
4-1
4 Elements of SPI Messages
You can use the Subsystem Programmatic Interface (SPI) for sending commands to
and decoding responses from the Safeguard subsystem and for obtaining event
messages issued by the Safeguard subsystem (through EMS.) For the procedures
used by an application to perform these tasks, see the SPI Programming Manual. For
a description of using SPI messages to communicate with the Safeguard subsystem
through SCP, see the SPI Common Extensions Manual.
The commands, responses, and event messages that are sent to and received from
the Safeguard subsystem are made up of special codes called tokens. Each token
contains its own identification and specific information, such as the command number
of a command or one element of an event message. Tokens can be single values or
structures consisting of several values. Some tokens, called header tokens, are
present in every command, response, or event message.
This manual does not give a complete explanation of tokens. It provides subsystem-
specific information about the tokens used to communicate with the Safeguard
subsystem. For more information about tokens, see the SPI Programming Manual. For
information about tokens common to all data communications subsystems, see the SPI
Common Extensions Manual.
This manual uses the Data Definition Language (DDL) to describe all tokens. For more
information about DDL, see the SPI Programming Manual.
Naming Guidelines for Applications
By convention, HP uses names beginning with the letter Z for all definitions and all
component fields of structures in its definition files. To avoid conflicts with names
defined by HP, do not begin any of your own names with an uppercase or lowercase Z.
Common Syntax Elements for Data
Communications
The rest of this section contains subsystem-specific information about elements of
commands, responses, and event messages. For more information, see the SPI
Common Extensions Manual.
Command Numbers
In the Safeguard subsystem, command numbers are represented by symbolic names
of the form ZCOM-CMD-name, where name represents the value that identifies the
command. ZSPI-TKN-COMMAND is a header token whose value is set to ZCOM-
CMD-name using SSINIT.