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CICS ADDRESS - Address Resolution

CICS ADDRESS provides address resolution capabilities in CICS environments. It enables programs to resolve addresses, manage address operations, and handle address resolution for communication and data access purposes.

Command Syntax

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       EXEC CICS ADDRESS
            [COMMAREA(commarea-address)]
            [EIB(eib-address)]
            [TASK(task-address)]
            [RESP(response-code)]
            [RESP2(response-code-2)]
       END-EXEC.

Parameters

COMMAREA(commarea-address)

Specifies the variable to receive the address of the communication area. This parameter provides access to the COMMAREA address for data exchange.

EIB(eib-address)

Specifies the variable to receive the address of the Execute Interface Block. This parameter provides access to the EIB address for system information.

TASK(task-address)

Specifies the variable to receive the address of the current task control block. This parameter provides access to the task address for task management.

RESP(response-code)

Specifies the response code variable to receive the operation result. This parameter provides error handling and status information.

RESP2(response-code-2)

Specifies the secondary response code variable for additional error information. This parameter provides extended error details when available.

Address Types

Communication Area Address

ADDRESS resolves the communication area address, enabling programs to access data passed between CICS transactions and programs.

Execute Interface Block Address

The command resolves the EIB address, providing access to system information, transaction details, and execution context.

Task Control Block Address

Task address resolution enables access to task-specific information and control structures for task management operations.

System Control Block Address

System control block addresses provide access to CICS system information and control structures for system operations.

Programming Examples

Basic Address Resolution

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       WORKING-STORAGE SECTION.
       01  COMMAREA-ADDR     POINTER.
       01  EIB-ADDR          POINTER.
       01  TASK-ADDR         POINTER.
       01  RESPONSE-CODE     PIC S9(8) COMP.
       01  RESPONSE-CODE-2   PIC S9(8) COMP.
 
       PROCEDURE DIVISION.
           EXEC CICS ADDRESS
                COMMAREA(COMMAREA-ADDR)
                EIB(EIB-ADDR)
                TASK(TASK-ADDR)
                RESP(RESPONSE-CODE)
                RESP2(RESPONSE-CODE-2)
           END-EXEC
           
           IF RESPONSE-CODE = 0
               DISPLAY 'Addresses resolved successfully'
               DISPLAY 'COMMAREA address: ' COMMAREA-ADDR
               DISPLAY 'EIB address: ' EIB-ADDR
               DISPLAY 'Task address: ' TASK-ADDR
           ELSE
               DISPLAY 'Error resolving addresses: ' RESPONSE-CODE
           END-IF.

Communication Area Access

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       WORKING-STORAGE SECTION.
       01  COMMAREA-ADDR     POINTER.
       01  COMMAREA-DATA     PIC X(100).
       01  RESPONSE-CODE     PIC S9(8) COMP.
       01  RESPONSE-CODE-2   PIC S9(8) COMP.
       01  DATA-LENGTH       PIC S9(8) COMP.
 
       PROCEDURE DIVISION.
           EXEC CICS ADDRESS
                COMMAREA(COMMAREA-ADDR)
                RESP(RESPONSE-CODE)
                RESP2(RESPONSE-CODE-2)
           END-EXEC
           
           IF RESPONSE-CODE = 0
               IF COMMAREA-ADDR NOT = NULL
                   SET ADDRESS OF COMMAREA-DATA TO COMMAREA-ADDR
                   MOVE FUNCTION LENGTH(COMMAREA-DATA) TO DATA-LENGTH
                   DISPLAY 'COMMAREA data accessed successfully'
                   DISPLAY 'Data length: ' DATA-LENGTH
                   DISPLAY 'Data content: ' COMMAREA-DATA
               ELSE
                   DISPLAY 'No COMMAREA data available'
               END-IF
           ELSE
               DISPLAY 'Error accessing COMMAREA: ' RESPONSE-CODE
           END-IF.

EIB Information Access

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       WORKING-STORAGE SECTION.
       01  EIB-ADDR          POINTER.
       01  EIB-DATA.
           05  EIBTRNID      PIC X(4).
           05  EIBTASKN      PIC S9(8) COMP.
           05  EIBDATE       PIC S9(8) COMP.
           05  EIBTIME       PIC S9(8) COMP.
           05  EIBRESP       PIC S9(8) COMP.
       01  RESPONSE-CODE     PIC S9(8) COMP.
       01  RESPONSE-CODE-2   PIC S9(8) COMP.
 
       PROCEDURE DIVISION.
           EXEC CICS ADDRESS
                EIB(EIB-ADDR)
                RESP(RESPONSE-CODE)
                RESP2(RESPONSE-CODE-2)
           END-EXEC
           
           IF RESPONSE-CODE = 0
               IF EIB-ADDR NOT = NULL
                   SET ADDRESS OF EIB-DATA TO EIB-ADDR
                   DISPLAY 'EIB information accessed successfully'
                   DISPLAY 'Transaction ID: ' EIBTRNID
                   DISPLAY 'Task number: ' EIBTASKN
                   DISPLAY 'Date: ' EIBDATE
                   DISPLAY 'Time: ' EIBTIME
                   DISPLAY 'Response code: ' EIBRESP
               ELSE
                   DISPLAY 'EIB address not available'
               END-IF
           ELSE
               DISPLAY 'Error accessing EIB: ' RESPONSE-CODE
           END-IF.

Error Handling

Response Code 0

Successful address resolution. The requested addresses have been successfully resolved and are available for use.

Response Code 8

Invalid address request. The specified address type is invalid or not supported in the current context.

Response Code 12

Address not available. The requested address is not available in the current execution context.

Response Code 16

Invalid address format. The address format is invalid or incompatible with the current system configuration.

Response Code 20

Address resolution failed. The address resolution operation failed due to system conditions.

Performance Considerations

Address Resolution Efficiency

ADDRESS efficiently resolves addresses, but frequent address resolution operations may impact system performance.

Memory Access Optimization

Proper memory access optimization ensures efficient use of resolved addresses and prevents memory access violations.

Address Validation

Address validation ensures that resolved addresses are valid and safe to use for memory access operations.

Best Practices

Error Handling

Always check response codes and handle errors appropriately, especially for address availability and validity.

Address Validation

Validate resolved addresses before use to ensure they are not null and point to valid memory locations.

Memory Safety

Ensure memory safety when accessing data through resolved addresses to prevent memory access violations.

Address Management

Manage resolved addresses efficiently and avoid unnecessary address resolution operations to optimize performance.

Explain It Like I's 5 Years Old

Imagine you're looking for your friend's house, and you need to know their address. CICS ADDRESS is like asking someone for the address of your friend's house so you can find it.

The COMMAREA address is like the address of a special mailbox where messages are stored. The EIB address is like the address of a special office that has information about what's happening. The task address is like the address of your current job or activity.

Just like you need to make sure the address is correct before you go there, the program needs to make sure the address is valid before it tries to use it.

Exercises

Exercise 1: Basic Address Resolution

Write a program that uses ADDRESS to resolve COMMAREA, EIB, and task addresses and display the resolved addresses.

Exercise 2: Communication Area Access

Create a program that resolves the COMMAREA address and accesses the data stored in the communication area.

Exercise 3: EIB Information Processing

Implement a program that resolves the EIB address and processes the execution interface block information.

Related Concepts

CICS Memory Management

Understanding CICS memory management and addressing

CICS Communication Areas

Learning about CICS communication areas and data exchange

CICS Execute Interface Block

Understanding CICS EIB and system information access

CICS Error Handling

Learning about CICS error handling and response codes