In JCL that runs a COBOL program using an external sort utility, how do you define the sort work files or sort file so that the COBOL program can perform the sort?

Introduction / Context:
Many COBOL batch programs rely on an external sort utility to sort records based on keys. When you use the COBOL SORT statement, the JCL for the job must allocate the required sort work files and sometimes the input and output data sets for the sort utility. If these files are not correctly defined, the sort will fail at execution time. This question asks how to define these sort files in JCL.

Given Data / Assumptions:

• The job runs a COBOL program that issues a SORT statement.
• A system sort utility such as DFSORT or Syncsort is used under the covers to perform the actual sort work.
• The sort utility expects certain DD names such as SORTWKnn, SORTIN, and SORTOUT to be present in the JCL.
• The COBOL program references sort file names that must correspond to DD names in the step.

Concept / Approach:
In the JCL step that executes the COBOL load module, you allocate sort work data sets and sort input and output data sets that the sort utility will use. This is often done through DD names like SORTWK01, SORTWK02 and so on, sized appropriately for expected volumes. The COBOL program may reference a logical sort file name that the compiler maps to the sort utility, and JCL must provide matching DD statements. In some configurations, SORTIN and SORTOUT represent the data to be sorted and the sorted output, while SORTWKnn data sets hold temporary work data during the sort.

Step-by-Step Solution:
Step 1: Identify which sort utility runs on the system and what default DD names it expects for sort work and data sets. Step 2: In the JCL step that executes the COBOL program, allocate SORTWK or similar work data sets with adequate space and unit attributes. Step 3: Allocate SORTIN and SORTOUT or the equivalent input and output data sets that hold records before and after the sort operation. Step 4: Ensure that the DD names used in JCL match the logical file names or default names used by the COBOL compiler and sort utility.

Verification / Alternative check:
Examples in COBOL and JCL documentation show COBOL SORT statements accompanied by JCL with SORTWKnn DD statements and sometimes explicit SORTIN and SORTOUT definitions. When these DD statements are omitted, abend messages from the sort utility indicate missing or insufficient work files. This behavior confirms that defining appropriate sort work and data sets in JCL is essential and that the correct answer is the one that describes this allocation pattern.

Why Other Options Are Wrong:
Option B is wrong because sort utilities do not automatically allocate all required files without any DD statements; they expect at least some work or data sets to be defined. Option C incorrectly suggests that all sort file definitions reside only in COBOL source and have no JCL representation, which is not accurate for typical mainframe environments. Option D suggests using only TSO allocations, but batch jobs rely on JCL DD statements at execution time. Option E misuses CICS ENQ, which does not apply to JCL allocation in batch.

Common Pitfalls:
A common pitfall is underestimating space requirements for SORTWK data sets, leading to sort failures when data volumes grow. Another issue is mismatching DD names between the COBOL program and the JCL, causing the sort utility to fail to locate required files. Some sites rely heavily on installation defaults and forget to adjust JCL when moving jobs between systems. Carefully defining sort files in JCL, with correct DD names and adequate space, ensures that COBOL sorts run reliably in production.

Final Answer:
By coding SORTWK or other sort work DD statements, or a SORTIN and SORTOUT data set as required by the sort utility, and by matching the COBOL program sort file names to these DD names in the JCL step