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CICS WAIT JOURNALNUM - Journal Number Waiting

CICS WAIT JOURNALNUM suspends the current task until a specific journal number is available. It enables programs to wait for journal numbers, manage journal operations, and handle journal number waiting in CICS applications.

What is CICS WAIT JOURNALNUM?

CICS WAIT JOURNALNUM is a command that allows programs to suspend the current task until a specific journal number is available. It provides journal waiting capabilities, task coordination, and journal management for CICS applications.

Command Syntax

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EXEC CICS WAIT JOURNALNUM
    JOURNALNUM(journal-number)
    [RESP(response-code)]
END-EXEC

Parameters

Required Parameters

  • JOURNALNUM(journal-number) - Number of the journal to wait for

Optional Parameters

  • RESP(response-code) - Response code variable

Programming Examples

Basic Journal Number Waiting

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WORKING-STORAGE SECTION.
01  JOURNAL-NUMBER      PIC S9(8) COMP VALUE 1.
01  RESPONSE-CODE        PIC S9(8) COMP.
 
PROCEDURE DIVISION.
    DISPLAY 'Waiting for journal number: ' JOURNAL-NUMBER
    
    *> Wait for the journal to be available
    EXEC CICS WAIT JOURNALNUM
        JOURNALNUM(JOURNAL-NUMBER)
        RESP(RESPONSE-CODE)
    END-EXEC.
    
    IF RESPONSE-CODE = DFHRESP(NORMAL)
        DISPLAY 'Journal available successfully'
        DISPLAY 'Continuing with processing...'
        
        *> Process the journal
        PERFORM PROCESS-JOURNAL
    ELSE
        IF RESPONSE-CODE = DFHRESP(TIMEOUT)
            DISPLAY 'Timeout waiting for journal'
        ELSE
            DISPLAY 'Error waiting for journal: ' RESPONSE-CODE
        END-IF
    END-IF.
 
PROCESS-JOURNAL.
    DISPLAY 'Processing journal number: ' JOURNAL-NUMBER
    *> Add journal processing logic here
    EXIT.

Error Handling

Common Response Codes

  • DFHRESP(NORMAL) - Journal available successfully
  • DFHRESP(TIMEOUT) - Timeout waiting for journal
  • DFHRESP(INVREQ) - Invalid request or parameter
  • DFHRESP(NOTAUTH) - Not authorized to wait for journal

Performance Considerations

Efficiency

  • • Task Suspension - WAIT JOURNALNUM suspends the task, freeing CPU resources
  • • Timeout Management - Use appropriate timeout values to avoid indefinite waits
  • • Throughput Impact - Consider the impact on transaction throughput

Best Practices

  • • Error Handling - Always check the response code for error handling
  • • Journal Naming - Use meaningful journal numbers for easier management
  • • Coordination - Coordinate journal writing with journal waiting

Explain It Like I'm 5 Years Old

Think of CICS WAIT JOURNALNUM like waiting for a specific numbered notebook:

  • • Numbered Notebook: "You want notebook number 5" - Journal number
  • • Wait for It: "You wait for someone to finish using it" - WAIT JOURNALNUM
  • • Notebook Free: "When they're done, you can use it" - Journal available
  • • Start Writing: "You start writing in your notebook" - Process journal

Exercises

Exercise 1: Basic Journal Waiting

Create a program that waits for a journal number and then processes it.

Exercise 2: Journal Writing

Write a program that writes to a journal number for another task to wait for.

Exercise 3: Error Handling

Implement error handling for the WAIT JOURNALNUM command.

Related Concepts

Journal Management

Managing journals in CICS

WRITE JOURNALNUM

Writing to journals

Task Coordination

Coordinating tasks

Synchronization

Synchronizing tasks

Error Handling

Handling journal errors