EMS Manual

Example of Retrieving Event Messages
EMS Manual—426909-005
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Overview of Application Logic
Overview of Application Logic
The example application in this appendix:
1. Starts a consumer distributor
2. Prompts the user for a CPU number
3. Opens the distributor for SPI communication; sends a distributor CONTROL
command message that:

Loads the compiled filter, which selects the event messages that originated on
the specified CPU

Passes the CPU number to the filter as a parameter

Connects $0 to the distributor as a source collector
4. Enters a loop that:

Requests filter-specified event messages from the consumer distributor
through use of a GETEVENT command message and response

Displays (at the terminal) the text that the EMSTEXT procedure produced,
based on the event message.
The program example consists of source statements for:

The DDL file that defines the subsystem ID and token name used by the filter
parameter

The event-message filter specification

The TAL program, which can be divided roughly as:

Definitions common to the TAL procedures

The get^cpu^num procedure, which prompts the user for the CPU number

The spi^control procedure, which generates and sends one distributor
CONTROL command message and processes the response

The displ^event procedure, which calls the EMSTEXT procedure to produce
display text and sends the formatted text to the terminal

The getevent^loop procedure, which generates and sends one distributor
GETEVENT command message and calls the displ^event procedure

The dist^intfc MAIN procedure

The TACL main source module

The COBOL main source module

The C main source module