SPI Common Extensions Manual

Introduction to SPI Extensions

SPI Common Extensions Manual—427508-001

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SPI Data Definitions

SPI-defined data items used to build SPI messages include tokens, values, command

numbers, message headers, and error numbers. You define these items using the

Compaq Data Definition Language (DDL), and provide them to programmers in

definition files that have names beginning with the defining subsystem’s abbreviation;

for example, ZSPI or ZCOM.

There is a definition file specifically suited to each of the programming languages

supported by SPI. To use these predefined items, add the definitions from the

appropriate definition file to their source code or, for Compaq Tandem Advanced

Command Language (TACL), load the TACL definitions or attach the appropriate

SEGF segment file.

Extended SPI provides its own set of definition files:

•

Files with names beginning with ZCOM contain the extended SPI definitions.

•

ZSCP files contain definitions used with the SCP.

•

ZCMK definitions are used by many NonStop Kernel subsystems that are based on

a common implementation of the extended SPI interface.

•

ZCDG definitions appear in common diagnostic event messages.

SPI and EMS

Event messages created using the Event Management Service (EMS) are a form of

SPI message, and the EMS procedures with which event messages are manipulated

are based on SPI procedures. For information on EMS, see the

EMS Manual

Subsystems can use EMS to log event messages. Events are noteworthy processing

situations, for example:

1. An event provides notification that a subsystem request table is full and indicates

that no additional requests can be accepted until table space becomes available.

2. The event results in an event message that contains information about the event.

3. Event messages are sent to a collector that archives them.

4. An EMS consumer distributor, which you had already created, uses a filter to

extract a particular subset of these event messages.

5. An application accesses this distributor to retrieve event messages and uses the

messages to monitor subsystems and their objects.

For Common Events Defined By... See...

ZCOM Section 6, ZCOM Event Messages

ZCMK Appendix B, ZCMK Definitions

ZCDG Appendix C, ZCDG Definitions