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CICS LOCATE - Locate

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

What is CICS LOCATE?

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

Command Syntax

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EXEC CICS LOCATE
    [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 locate 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

Locate Types

1. Basic Locates

  • Basic locates: Standard locate operations that handle simple locating without special formatting
  • Mapped locates: Locate operations that use predefined field mappings to structure locate data
  • Unmapped locates: Raw locate operations that handle unstructured locating without predefined field mappings
  • Custom locates: Specialized locate operations designed for specific application requirements

2. Advanced Locates

  • Advanced locates: Complex locate operations that handle sophisticated locating processing and validation
  • Secure locates: Locate operations that include encryption and security features for sensitive locating
  • Encrypted locates: Locate operations that automatically encrypt locate data
  • Compressed locates: Locate operations that handle compressed locating streams and automatically compress locate data

3. Specialized Locates

  • Specialized locates: Locate operations tailored for specific protocols or communication methods
  • High-performance locates: Optimized locate operations designed for maximum throughput and efficiency
  • Low-latency locates: Locate operations optimized for minimal delay and real-time processing requirements
  • High-throughput locates: Locate operations designed to handle large volumes of locating 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.
    * Locate operation
    EXEC CICS LOCATE
        RESP(WS-RESPONSE)
        RESP2(WS-RESPONSE2)
    END-EXEC.
    
    IF WS-RESPONSE NOT EQUAL DFHRESP(NORMAL)
        EXEC CICS WRITE OPERATOR
            TEXT('LOCATE command failed')
        END-EXEC
        EXEC CICS RETURN END-EXEC
    END-IF.
    
    * Locate operation completed successfully
    * Continue processing

Locate Processing

1. Locate Preparation

Locate preparation includes:

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

2. Locate Transmission

Locate transmission includes:

  • Locate routing - directing locate data to the appropriate processing location
  • Locate delivery - ensuring locate data reaches the correct destination within the application
  • Transmission confirmation - verifying that locate 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 locate data for presentation or further processing
  • User experience - ensuring smooth data flow and responsive application behavior
  • Performance optimization - maximizing locate efficiency and minimizing resource usage

Common Response Codes

Success Response Codes

  • NORMAL (0): Locate operation completed successfully - locating was completed without errors
  • LOCATE (4): Locate operation completed - operation completed with locate-specific status

Error Response Codes

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

Best Practices

1. Locate Preparation

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

2. Error Handling

  • Check all response codes - always examine both RESP and RESP2 for complete error information
  • Handle locate failures - implement appropriate recovery mechanisms for failed locate 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 locate operations - reduce unnecessary locate calls to improve overall performance
  • Use efficient locate 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 locate operations

Explain It Like I'm 5 Years Old

Imagine you're looking for a toy in your room:

When you want to find a toy in your room, you look around and search for it. If you find the toy, you know where it is. If you don't find the toy, you know it's not there.

CICS LOCATE is like looking for a toy in your room. The computer program looks around and searches for data. If it finds the data, it knows where it is. If it doesn't find the data, it knows it's not there.

Just like you look for toys in your room, the computer program looks for data in memory!

Exercises

Exercise 1: Locate Operation

Write a CICS LOCATE command to perform a locate operation.

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

Exercise 2: Locate Processing

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

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

Quiz

Question 1

What is the primary purpose of CICS LOCATE?

Answer: B) To provide locate management capabilities

Question 2

Which parameter specifies the response code?

Answer: A) RESP

Related Concepts

CICS Locate Processing

Locate processing and output in CICS

CICS User Management

User management and user interaction in CICS

CICS Output Processing

Output processing and locate display in CICS