What is CICS STARTBR command?

CICS STARTBR is a command that initiates browse operations in CICS environments, enabling programs to start sequential file access sessions for data processing and reporting purposes.

How does CICS STARTBR work?

STARTBR initiates browse operations by specifying a file name and optional starting key, enabling programs to begin sequential access to file records in key order.

What are the main parameters for CICS STARTBR?

The main parameters include FILE for the file name, RIDFLD for the starting key, KEYLENGTH for key length, GENERIC for partial matching, REQID for concurrent operations, and RESP for response codes.

How do you handle errors with CICS STARTBR?

Error handling involves checking response codes, with code 0 indicating success, code 8 indicating invalid file name, code 12 indicating invalid key length, and other codes indicating various error conditions.

What types of browse operations are supported by CICS STARTBR?

Browse types include sequential browse (key order access), key-based browse (specific starting position), generic browse (partial key matching), and concurrent browse (multiple simultaneous operations).

CICS STARTBR - Start Browse Operation

CICS STARTBR provides browse operation initiation capabilities in CICS environments. It enables programs to start browse operations, manage file operations, and handle browse initiation for sequential file access and data processing.

Command Syntax

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       EXEC CICS STARTBR
            [FILE(file-name)]
            [RIDFLD(record-id)]
            [KEYLENGTH(key-length)]
            [GENERIC]
            [REQID(request-id)]
            [RESP(response-code)]
            [RESP2(response-code-2)]
       END-EXEC.

Parameters

FILE(file-name)

Specifies the name of the file for which the browse operation will be started. This parameter identifies the target file for browse initiation.

RIDFLD(record-id)

Specifies the record identifier field containing the starting key for the browse operation. This parameter determines the browse starting point.

KEYLENGTH(key-length)

Specifies the length of the key field used for the browse operation. This parameter controls the key matching for browse positioning.

GENERIC

Specifies that the browse operation should use generic key matching for partial key searches and pattern matching.

REQID(request-id)

Specifies a request identifier for the browse operation. This parameter enables multiple concurrent browse operations on the same file.

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.

Browse Types

Sequential Browse

STARTBR initiates sequential browse operations, enabling programs to access records in key order for data processing and reporting.

Key-Based Browse

The command supports key-based browse operations for starting browse sessions at specific key positions within files.

Generic Browse

Generic browse enables partial key matching and pattern-based searches for flexible data access and retrieval.

Concurrent Browse

Concurrent browse supports multiple simultaneous browse operations on the same file using request identifiers.

Programming Examples

Basic Browse Initiation

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       WORKING-STORAGE SECTION.
       01  FILE-NAME         PIC X(8) VALUE 'CUSTOMER'.
       01  RECORD-KEY        PIC X(10) VALUE 'CUST001'.
       01  KEY-LENGTH        PIC S9(8) COMP VALUE 10.
       01  RESPONSE-CODE     PIC S9(8) COMP.
       01  RESPONSE-CODE-2   PIC S9(8) COMP.
 
       PROCEDURE DIVISION.
           EXEC CICS STARTBR
                FILE(FILE-NAME)
                RIDFLD(RECORD-KEY)
                KEYLENGTH(KEY-LENGTH)
                RESP(RESPONSE-CODE)
                RESP2(RESPONSE-CODE-2)
           END-EXEC
           
           IF RESPONSE-CODE = 0
               DISPLAY 'Browse operation started successfully'
               DISPLAY 'File: ' FILE-NAME
               DISPLAY 'Starting key: ' RECORD-KEY
           ELSE
               DISPLAY 'Error starting browse: ' RESPONSE-CODE
           END-IF.

Generic Browse Operation

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       WORKING-STORAGE SECTION.
       01  FILE-NAME         PIC X(8) VALUE 'CUSTOMER'.
       01  RECORD-KEY        PIC X(10) VALUE 'CUST'.
       01  KEY-LENGTH        PIC S9(8) COMP VALUE 4.
       01  RESPONSE-CODE     PIC S9(8) COMP.
       01  RESPONSE-CODE-2   PIC S9(8) COMP.
 
       PROCEDURE DIVISION.
           EXEC CICS STARTBR
                FILE(FILE-NAME)
                RIDFLD(RECORD-KEY)
                KEYLENGTH(KEY-LENGTH)
                GENERIC
                RESP(RESPONSE-CODE)
                RESP2(RESPONSE-CODE-2)
           END-EXEC
           
           IF RESPONSE-CODE = 0
               DISPLAY 'Generic browse started successfully'
               DISPLAY 'File: ' FILE-NAME
               DISPLAY 'Generic key: ' RECORD-KEY
               DISPLAY 'Will browse all records starting with CUST'
           ELSE
               DISPLAY 'Error starting generic browse: ' RESPONSE-CODE
           END-IF.

Concurrent Browse Operations

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       WORKING-STORAGE SECTION.
       01  FILE-NAME         PIC X(8) VALUE 'CUSTOMER'.
       01  RECORD-KEY        PIC X(10).
       01  KEY-LENGTH        PIC S9(8) COMP VALUE 10.
       01  REQUEST-ID        PIC X(8).
       01  RESPONSE-CODE     PIC S9(8) COMP.
       01  RESPONSE-CODE-2   PIC S9(8) COMP.
       01  BROWSE-COUNT      PIC S9(8) COMP VALUE 0.
 
       PROCEDURE DIVISION.
           PERFORM START-BROWSE-001
           PERFORM START-BROWSE-002
           PERFORM START-BROWSE-003.
           
       START-BROWSE-001.
           MOVE 'CUST001' TO RECORD-KEY
           MOVE 'REQ001' TO REQUEST-ID
           EXEC CICS STARTBR
                FILE(FILE-NAME)
                RIDFLD(RECORD-KEY)
                KEYLENGTH(KEY-LENGTH)
                REQID(REQUEST-ID)
                RESP(RESPONSE-CODE)
                RESP2(RESPONSE-CODE-2)
           END-EXEC
           IF RESPONSE-CODE = 0
               ADD 1 TO BROWSE-COUNT
               DISPLAY 'Browse 001 started'
           END-IF.
           
       START-BROWSE-002.
           MOVE 'CUST050' TO RECORD-KEY
           MOVE 'REQ002' TO REQUEST-ID
           EXEC CICS STARTBR
                FILE(FILE-NAME)
                RIDFLD(RECORD-KEY)
                KEYLENGTH(KEY-LENGTH)
                REQID(REQUEST-ID)
                RESP(RESPONSE-CODE)
                RESP2(RESPONSE-CODE-2)
           END-EXEC
           IF RESPONSE-CODE = 0
               ADD 1 TO BROWSE-COUNT
               DISPLAY 'Browse 002 started'
           END-IF.
           
       START-BROWSE-003.
           MOVE 'CUST100' TO RECORD-KEY
           MOVE 'REQ003' TO REQUEST-ID
           EXEC CICS STARTBR
                FILE(FILE-NAME)
                RIDFLD(RECORD-KEY)
                KEYLENGTH(KEY-LENGTH)
                REQID(REQUEST-ID)
                RESP(RESPONSE-CODE)
                RESP2(RESPONSE-CODE-2)
           END-EXEC
           IF RESPONSE-CODE = 0
               ADD 1 TO BROWSE-COUNT
               DISPLAY 'Browse 003 started'
           END-IF.

Error Handling

Response Code 0

Successful browse initiation. The browse operation has been successfully started and is ready for data access.

Response Code 8

Invalid file name. The specified file name is invalid or not supported.

Response Code 12

Invalid key length. The specified key length is invalid or incompatible with the file structure.

Response Code 16

Start operation failed. The browse initiation operation failed due to system conditions.

Response Code 20

Browse not available. The browse operation capability is not available in the current execution context.

Performance Considerations

Browse Efficiency

STARTBR efficiently initiates browse operations, but excessive concurrent browses may impact system performance.

Resource Management

Proper resource management ensures efficient browse operations and prevents resource exhaustion and system performance issues.

Key Optimization

Key optimization ensures efficient browse positioning and minimizes resource consumption during browse operations.

Best Practices

Error Handling

Always check response codes and handle errors appropriately, especially for file validation and browse availability.

Resource Management

Implement proper resource management by ensuring browse operations are properly terminated to prevent resource leaks.

Browse Optimization

Optimize browse operations by using appropriate key lengths and positioning strategies for efficient data access.

Concurrent Management

Manage concurrent browse operations efficiently by using request identifiers and monitoring resource consumption.

Explain It Like I's 5 Years Old

Imagine you want to look through a big book, and you need to open it to a specific page to start reading. CICS STARTBR is like opening the book to the page you want to start reading from.

The file name is like the name of the book you want to read, and the record key is like the page number where you want to start. When you start the browse, you're telling the program where to begin looking through the book.

Just like you need to open a book before you can read it, the program needs to start a browse operation before it can look through the file.

Exercises

Exercise 1: Basic Browse Initiation

Write a program that uses STARTBR to initiate a browse operation and verify the initiation was successful.

Exercise 2: Generic Browse Operations

Create a program that uses generic browse to search for records with partial key matches.

Exercise 3: Concurrent Browse Management

Implement a browse management system that handles multiple concurrent browse operations on the same file.

CICS STARTBR - Start Browse Operation

Command Syntax

Parameters

FILE(file-name)

RIDFLD(record-id)

KEYLENGTH(key-length)

GENERIC

REQID(request-id)

RESP(response-code)

RESP2(response-code-2)

Browse Types

Sequential Browse

Key-Based Browse

Generic Browse

Concurrent Browse

Programming Examples

Basic Browse Initiation

Generic Browse Operation

Concurrent Browse Operations

Error Handling

Response Code 0

Response Code 8

Response Code 12

Response Code 16

Response Code 20

Performance Considerations

Browse Efficiency

Resource Management

Key Optimization

Best Practices

Error Handling

Resource Management

Browse Optimization

Concurrent Management

Explain It Like I's 5 Years Old

Exercises

Exercise 1: Basic Browse Initiation

Exercise 2: Generic Browse Operations

Exercise 3: Concurrent Browse Management

Related Concepts

CICS File Management

CICS Browse Operations

CICS Sequential Processing

CICS Error Handling

Related Pages