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CICS RETURN - Return

CICS RETURN provides return management capabilities, enabling return processing and output processing in CICS environments. It provides efficient return capabilities for CICS applications.

What is CICS RETURN?

CICS RETURN provides return management capabilities, enabling return processing and output processing. It provides efficient return capabilities, allowing applications to manage return operations.

Command Syntax

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EXEC CICS RETURN
    [RESP(response-code)]
    [RESP2(response-code-2)]
END-EXEC.

Parameters Explained

RESP Parameters

Response codes returned by the command:

  • RESP: Primary response code - indicates the success or failure of the return operation
  • RESP2: Secondary response code - provides additional error information when RESP indicates failure
  • Always check these codes for command success before proceeding with data processing
  • Handle command failures appropriately to prevent application errors

Return Types

1. Basic Returns

  • Basic returns: Standard return operations that handle simple returning without special formatting
  • Mapped returns: Return operations that use predefined field mappings to structure return data
  • Unmapped returns: Raw return operations that handle unstructured returning without predefined field mappings
  • Custom returns: Specialized return operations designed for specific application requirements

2. Advanced Returns

  • Advanced returns: Complex return operations that handle sophisticated returning processing and validation
  • Secure returns: Return operations that include encryption and security features for sensitive returning
  • Encrypted returns: Return operations that automatically encrypt return data
  • Compressed returns: Return operations that handle compressed returning streams and automatically compress return data

3. Specialized Returns

  • Specialized returns: Return operations tailored for specific protocols or communication methods
  • High-performance returns: Optimized return operations designed for maximum throughput and efficiency
  • Low-latency returns: Return operations optimized for minimal delay and real-time processing requirements
  • High-throughput returns: Return operations designed to handle large volumes of returning efficiently

Implementation Example

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WORKING-STORAGE SECTION.
01 WS-RESPONSE            PIC S9(8) COMP.
01 WS-RESPONSE2           PIC S9(8) COMP.
 
PROCEDURE DIVISION.
    * Return operation
    EXEC CICS RETURN
        RESP(WS-RESPONSE)
        RESP2(WS-RESPONSE2)
    END-EXEC.
    
    IF WS-RESPONSE NOT EQUAL DFHRESP(NORMAL)
        EXEC CICS WRITE OPERATOR
            TEXT('RETURN command failed')
        END-EXEC
        EXEC CICS RETURN END-EXEC
    END-IF.
    
    * Return operation completed successfully
    * Continue processing

Return Processing

1. Return Preparation

Return preparation includes:

  • Return validation - ensuring the return operation is properly configured and authorized
  • Return formatting - preparing data structures and buffers for return data
  • Return encoding - setting up proper character encoding and data transformation
  • Return processing - initializing the return operation and preparing for returning

2. Return Transmission

Return transmission includes:

  • Return routing - directing return data to the appropriate processing location
  • Return delivery - ensuring return data reaches the correct destination within the application
  • Transmission confirmation - verifying that return was completed successfully
  • Error handling - managing transmission failures and implementing retry mechanisms

3. Output Management

Output management includes:

  • User management - handling user sessions and maintaining connection state
  • Output formatting - structuring return data for presentation or further processing
  • User experience - ensuring smooth data flow and responsive application behavior
  • Performance optimization - maximizing return efficiency and minimizing resource usage

Common Response Codes

Success Response Codes

  • NORMAL (0): Return operation completed successfully - returning was completed without errors
  • RETURN (4): Return operation completed - operation completed with return-specific status

Error Response Codes

  • INVREQ (16): Invalid request - the return operation parameters are incorrect or unauthorized
  • NOTFND (20): Resource not found - the specified return resource does not exist
  • LENGERR (22): Length error - the return data length exceeds expected limits
  • RETURN (24): Return error - a return-specific error occurred during the operation

Best Practices

1. Return Preparation

  • Prepare return appropriately - ensure all necessary resources and configurations are in place
  • Validate return content - verify that return data meets expected format and quality standards
  • Handle different return types - implement flexible processing to accommodate various returning formats
  • Ensure return integrity - maintain data consistency and prevent corruption during returning

2. Error Handling

  • Check all response codes - always examine both RESP and RESP2 for complete error information
  • Handle return failures - implement appropriate recovery mechanisms for failed return operations
  • Implement retry logic - provide automatic retry capabilities for transient failures
  • Log error conditions - maintain detailed logs for troubleshooting and monitoring purposes

3. Performance Optimization

  • Minimize return operations - reduce unnecessary return calls to improve overall performance
  • Use efficient return formats - choose appropriate data formats to minimize processing overhead
  • Optimize user updates - streamline user interface updates to reduce response time
  • Manage user resources - efficiently allocate and manage system resources for return operations

Explain It Like I'm 5 Years Old

Imagine you're going back home:

When you want to go back home, you walk back to your house. If you walk back to your house, you get home. If you don't walk back to your house, you don't get home.

CICS RETURN is like going back home. The computer program walks back to its starting place. If it walks back to its starting place, it gets home. If it doesn't walk back to its starting place, it doesn't get home.

Just like you go back home, the computer program goes back to its starting place!

Exercises

Exercise 1: Return Operation

Write a CICS RETURN command to perform a return operation.

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EXEC CICS RETURN
    RESP(WS-RESPONSE)
    RESP2(WS-RESPONSE2)
END-EXEC.

Exercise 2: Return Processing

How would you implement comprehensive return processing that handles different return types and requirements?

Answer: Identify different return types and appropriate handling, implement return validation and encoding, handle different return types and capabilities, implement proper error handling for return failures, optimize return operations for performance, and maintain return integrity throughout the process.

Quiz

Question 1

What is the primary purpose of CICS RETURN?

Answer: B) To provide return management capabilities

Question 2

Which parameter specifies the response code?

Answer: A) RESP

Related Concepts

CICS Return Processing

Return processing and output in CICS

CICS User Management

User management and user interaction in CICS

CICS Output Processing

Output processing and return display in CICS