What types of message purging are available?

Purge types include queue purge (message queue, selective, bulk, conditional), terminal purge (terminal, user, display, notification), system purge (system, log, audit, error), and data purge (data, file, record, batch).

How do I handle errors with CICS PURGE MESSAGE?

Always check the response code and implement appropriate error handling, including validation of purge requests, retry mechanisms for failed operations, and fallback procedures for purge errors.

What is the purpose of message purging?

Message purging enables queue cleanup, resource management, system optimization, storage management, and performance improvement by removing unnecessary or outdated messages from the system.

When should I use CICS PURGE MESSAGE?

Use this command when you need to clean up message queues, free up storage space, remove outdated messages, optimize system performance, or maintain queue integrity.

CICS PURGE MESSAGE - Message Purge Control

Q: What is CICS PURGE MESSAGE command used for?

CICS PURGE MESSAGE is used to purge or remove messages from message queues, terminals, or other message storage areas, providing message cleanup and queue management capabilities.

CICS PURGE MESSAGE provides message purging capabilities for programs and transactions. It enables programs to purge messages, manage message cleanup, and handle message purging in CICS environments.

What is CICS PURGE MESSAGE?

CICS PURGE MESSAGE is a command that allows programs to purge or remove messages from message queues, terminals, or other message storage areas. It provides message cleanup capabilities, queue management, and message purging for CICS applications.

Command Syntax

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EXEC CICS PURGE MESSAGE
    [QUEUE(queue-name)]
    [TERMINAL(terminal-id)]
    [MESSAGEID(message-id)]
    [RESP(response-code)]
END-EXEC

Parameters

Optional Parameters

QUEUE(queue-name) - Name of the message queue to purge
TERMINAL(terminal-id) - Terminal ID to purge messages from
MESSAGEID(message-id) - Specific message ID to purge
RESP(response-code) - Response code variable

Purge Types

Queue Purge

Purging messages from queues

• MESSAGE QUEUE PURGE - Purge all messages from queue
• SELECTIVE PURGE - Purge specific messages
• BULK PURGE - Purge multiple messages
• CONDITIONAL PURGE - Purge based on conditions

Terminal Purge

Purging messages from terminals

• TERMINAL MESSAGE PURGE - Purge terminal messages
• USER MESSAGE PURGE - Purge user messages
• DISPLAY PURGE - Purge display messages
• NOTIFICATION PURGE - Purge notification messages

System Purge

Purging system messages

• SYSTEM MESSAGE PURGE - Purge system messages
• LOG MESSAGE PURGE - Purge log messages
• AUDIT MESSAGE PURGE - Purge audit messages
• ERROR MESSAGE PURGE - Purge error messages

Data Purge

Purging data messages

• DATA MESSAGE PURGE - Purge data messages
• FILE MESSAGE PURGE - Purge file messages
• RECORD MESSAGE PURGE - Purge record messages
• BATCH MESSAGE PURGE - Purge batch messages

Programming Examples

Basic Message Purge

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       IDENTIFICATION DIVISION.
       PROGRAM-ID. PURGE01.
       DATA DIVISION.
       WORKING-STORAGE SECTION.
       01  QUEUE-NAME      PIC X(8) VALUE 'MSGQUEUE'.
       01  TERMINAL-ID     PIC X(4) VALUE 'TERM'.
       01  RESPONSE-CODE   PIC S9(8) COMP.
       01  PURGE-NEEDED   PIC X(1) VALUE 'Y'.
       
       PROCEDURE DIVISION.
           IF PURGE-NEEDED = 'Y'
               DISPLAY 'Purging messages from queue...'
               
               EXEC CICS PURGE MESSAGE
                   QUEUE(QUEUE-NAME)
                   TERMINAL(TERMINAL-ID)
                   RESP(RESPONSE-CODE)
               END-EXEC
               
               IF RESPONSE-CODE = DFHRESP(NORMAL)
                   DISPLAY 'Messages purged successfully'
                   DISPLAY 'Queue: ' QUEUE-NAME
                   DISPLAY 'Terminal: ' TERMINAL-ID
               ELSE
                   DISPLAY 'Failed to purge messages'
               END-IF
           ELSE
               DISPLAY 'No purge needed'
           END-IF
           
           EXEC CICS RETURN END-EXEC.

Advanced Message Purge

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       IDENTIFICATION DIVISION.
       PROGRAM-ID. PURGE02.
       DATA DIVISION.
       WORKING-STORAGE SECTION.
       01  QUEUE-NAME      PIC X(8) VALUE 'MSGQUEUE'.
       01  TERMINAL-ID     PIC X(4) VALUE 'TERM'.
       01  MESSAGE-ID      PIC X(8) VALUE 'MSG001'.
       01  RESPONSE-CODE   PIC S9(8) COMP.
       01  PURGE-TYPE     PIC X(1).
       01  PURGE-COUNT    PIC S9(4) COMP VALUE 0.
       
       PROCEDURE DIVISION.
           PERFORM DETERMINE-PURGE-TYPE
           PERFORM PURGE-MESSAGES
           
           EXEC CICS RETURN END-EXEC.
       
       DETERMINE-PURGE-TYPE.
           *> Add logic to determine purge type
           MOVE 'Q' TO PURGE-TYPE.
       
       PURGE-MESSAGES.
           EVALUATE PURGE-TYPE
               WHEN 'Q'
                   EXEC CICS PURGE MESSAGE
                       QUEUE(QUEUE-NAME)
                       RESP(RESPONSE-CODE)
                   END-EXEC
                   ADD 1 TO PURGE-COUNT
               WHEN 'T'
                   EXEC CICS PURGE MESSAGE
                       TERMINAL(TERMINAL-ID)
                       RESP(RESPONSE-CODE)
                   END-EXEC
                   ADD 1 TO PURGE-COUNT
               WHEN 'M'
                   EXEC CICS PURGE MESSAGE
                       MESSAGEID(MESSAGE-ID)
                       RESP(RESPONSE-CODE)
                   END-EXEC
                   ADD 1 TO PURGE-COUNT
               WHEN OTHER
                   DISPLAY 'Unknown purge type'
           END-EVALUATE
           
           IF RESPONSE-CODE = DFHRESP(NORMAL)
               DISPLAY 'Purge operation ' PURGE-COUNT ' successful'
           ELSE
               DISPLAY 'Purge operation ' PURGE-COUNT ' failed'
           END-IF.

Error Handling with Message Purge

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       IDENTIFICATION DIVISION.
       PROGRAM-ID. PURGE03.
       DATA DIVISION.
       WORKING-STORAGE SECTION.
       01  QUEUE-NAME      PIC X(8) VALUE 'MSGQUEUE'.
       01  RESPONSE-CODE   PIC S9(8) COMP.
       01  RETRY-COUNT    PIC S9(2) COMP VALUE 0.
       01  MAX-RETRIES    PIC S9(2) COMP VALUE 3.
       
       PROCEDURE DIVISION.
           PERFORM PURGE-WITH-ERROR-HANDLING
           
           EXEC CICS RETURN END-EXEC.
       
       PURGE-WITH-ERROR-HANDLING.
           PERFORM PURGE-MESSAGE
           
           IF RESPONSE-CODE NOT = DFHRESP(NORMAL)
               AND RETRY-COUNT < MAX-RETRIES
               ADD 1 TO RETRY-COUNT
               DISPLAY 'Retry ' RETRY-COUNT ' purging messages'
               PERFORM PURGE-WITH-ERROR-HANDLING
           END-IF.
       
       PURGE-MESSAGE.
           EXEC CICS PURGE MESSAGE
               QUEUE(QUEUE-NAME)
               RESP(RESPONSE-CODE)
           END-EXEC
           
           EVALUATE RESPONSE-CODE
               WHEN DFHRESP(NORMAL)
                   DISPLAY 'Messages purged successfully'
               WHEN DFHRESP(INVREQ)
                   DISPLAY 'Invalid purge request'
               WHEN DFHRESP(NOTFND)
                   DISPLAY 'Queue or messages not found'
               WHEN DFHRESP(NOTAUTH)
                   DISPLAY 'Not authorized to purge messages'
               WHEN DFHRESP(QIDERR)
                   DISPLAY 'Queue ID error'
               WHEN OTHER
                   DISPLAY 'Unexpected error occurred'
           END-EVALUATE.

Message Purge Management

Purge Control

• Purge Initiation - Initiate purge operations
• Purge Management - Manage purge processes
• Purge Monitoring - Monitor purge status
• Purge Completion - Complete purge operations

Queue Management

• Queue Cleanup - Clean up message queues
• Queue Optimization - Optimize queue performance
• Queue Monitoring - Monitor queue status
• Queue Maintenance - Maintain queue integrity

Resource Management

• Resource Cleanup - Clean up message resources
• Resource Optimization - Optimize resource usage
• Resource Monitoring - Monitor resource consumption
• Resource Recovery - Recover from resource issues

Error Recovery

• Error Detection - Detect purge errors
• Error Recovery - Recover from purge errors
• Retry Mechanisms - Implement retry logic
• Fallback Procedures - Use fallback procedures

Error Handling

Common Response Codes

DFHRESP(NORMAL) - Messages purged successfully
DFHRESP(INVREQ) - Invalid purge request
DFHRESP(NOTFND) - Queue or messages not found
DFHRESP(NOTAUTH) - Not authorized to purge messages
DFHRESP(QIDERR) - Queue ID error
DFHRESP(TERMIDERR) - Terminal ID error

Performance Considerations

Purge Efficiency

• Optimize purge operations - Use efficient purge patterns
• Minimize purge overhead - Reduce purge processing overhead
• Use appropriate purge types - Choose appropriate purge methods
• Monitor purge frequency - Track purge occurrence patterns

System Impact

• Monitor system impact - Track how purges affect the system
• Optimize purge handling - Ensure efficient purge processing
• Manage resource usage - Monitor resource consumption
• Track performance metrics - Monitor purge handling performance

Best Practices

Message Purge Best Practices

• Use purge operations judiciously
• Implement proper purge handling
• Ensure purge authorization
• Monitor purge operations
• Use appropriate purge timing
• Maintain purge audit trails
• Clean up resources properly

Explain It Like I'm 5 Years Old

Think of CICS PURGE MESSAGE like cleaning up your room:

• Messy Room: "Your room is messy with toys everywhere" - Messages in queue
• Clean Up: "Put all the toys away" - Purge messages
• Throw Away: "Throw away broken toys" - Remove old messages
• Organize: "Organize your room" - Clean up queue
• Clean Room: "Now your room is clean" - Messages purged

Exercises

Exercise 1: Basic Message Purge

Create a program that purges messages from a specific queue.

Exercise 2: Conditional Message Purge

Write a program that purges messages based on different conditions.

Exercise 3: Error Handling

Implement comprehensive error handling for message purge failures.

CICS PURGE MESSAGE - Message Purge Control

What is CICS PURGE MESSAGE?

Command Syntax

Parameters

Optional Parameters

Purge Types

Queue Purge

Terminal Purge

System Purge

Data Purge

Programming Examples

Basic Message Purge

Advanced Message Purge

Error Handling with Message Purge

Message Purge Management

Purge Control

Queue Management

Resource Management

Error Recovery

Error Handling

Common Response Codes

Performance Considerations

Purge Efficiency

System Impact

Best Practices

Message Purge Best Practices

Explain It Like I'm 5 Years Old

Exercises

Exercise 1: Basic Message Purge

Exercise 2: Conditional Message Purge

Exercise 3: Error Handling

Related Concepts

Message Handling

Queue Management

Resource Management

Cleanup Operations

Error Handling

Related Pages