What is the purpose of a "core dump" in COBOL debugging?
- A log of input/output operations
- A report of compilation errors
- A snapshot of the program's memory contents
- A summary of executed COBOL statements
In COBOL debugging, a "core dump" refers to a snapshot of the program's memory contents at a specific point in time. It helps developers analyze the state of the program's variables and memory structures, aiding in identifying the cause of issues.
_____ is the file access mode used when you only need to read records from a file in COBOL.
- EXTEND
- I-O
- INPUT
- OUTPUT
"INPUT" is the file access mode used in COBOL when you only need to read records from a file. This mode allows the program to read data from the specified file but does not allow writing or updating records.
In Object-Oriented COBOL, _____ allows a class to provide different implementations of a method based on the specific object type.
- Abstraction
- Encapsulation
- Inheritance
- Polymorphism
Polymorphism in Object-Oriented COBOL allows a class to provide different implementations of a method based on the specific object type. It enhances flexibility by enabling a single method name to have different behaviors in different classes.
In COBOL, when dealing with variable-length records, which data structure is used to determine the length of each record?
- Data Division
- File Section
- Record Description Table (RDT)
- Record Descriptor Entry (RDE)
In COBOL, the Record Descriptor Entry (RDE) is used to specify the length and structure of variable-length records. It contains information such as the starting position and length of each field within the record.
How can you ensure that a variable is accessible to multiple paragraphs within a procedure?
- Declare the variable with a GLOBAL clause
- Define the variable in the DATA DIVISION
- Include the variable in the PROCEDURE DIVISION header
- Use the GLOBAL paragraph to define the variable
To make a variable accessible to multiple paragraphs within a procedure in COBOL, you need to declare the variable in the DATA DIVISION. This ensures that the variable is known and can be referenced by any paragraph within the procedure.
The _____ debugging technique in COBOL involves isolating parts of the code to identify the source of a problem.
- Incremental
- Isolation
- Modular
- Stepwise
The "Isolation" debugging technique in COBOL involves isolating specific parts of the code for focused analysis. This helps identify the source of a problem by narrowing down the scope of investigation, facilitating efficient debugging.
When working with external files, the _____ clause is used for file access control.
- ACCESS
- CONTROL
- FILE
- ORGANIZATION
In COBOL, the ACCESS clause is used for file access control when working with external files. It specifies the type of access (e.g., sequential or random) that the program will have to the file.
When using the EXTERNAL clause in COBOL, how can you ensure variable visibility across different programs?
- By declaring the variable as REDEFINES in each program
- By declaring the variable in each program using the EXTERNAL clause
- By using the ENTRY statement in the calling program
- By using the GLOBAL clause along with the EXTERNAL clause
To ensure variable visibility across different programs, you can use the GLOBAL clause along with the EXTERNAL clause. This combination allows the variable to have global visibility, making it accessible across various program units.
In a large COBOL application, you have multiple programs that need to share a common data structure. How can subprograms help in managing this data sharing efficiently?
- COPY statement
- Global Data Section
- Parameter Passing
- Redefine Clause
Subprograms can efficiently manage data sharing by using Parameter Passing. By passing parameters, data can be exchanged between the main program and subprograms, ensuring modularity and reducing dependencies on global data.
When using the "EVALUATE" statement in COBOL, what is the purpose of the "WHEN OTHER" condition?
- To indicate the end of the "EVALUATE" block
- To specify an alternate condition if none of the preceding conditions is true
- To terminate the evaluation process
- To trigger an error if no condition is met
The "WHEN OTHER" condition in the "EVALUATE" statement serves as a catch-all condition. It is executed if none of the preceding conditions evaluates to true, providing a default action or handling unexpected situations.
What challenges might you encounter when processing variable-length records in COBOL programs?
- Difficulty in determining the end of each record
- Increased storage requirements
- Inefficient data retrieval
- Limited support in certain file systems
Processing variable-length records in COBOL programs may pose challenges, such as difficulty in determining the end of each record. Unlike fixed-length records, the varying lengths require additional considerations to identify the boundaries of individual records.
In COBOL, what is the purpose of the PERFORM statement?
- To declare a paragraph
- To define a section
- To execute a set of statements repeatedly
- To initialize variables
The PERFORM statement in COBOL is used to execute a set of statements repeatedly. It provides a way to create loops and control the flow of execution within the program.