On an IBM mainframe, how can you check the syntax of a JCL job without actually executing the job steps?

Introduction / Context:
When writing JCL, it is often useful to validate the syntax before running a job that might consume resources or affect data. IBM mainframe systems provide a feature that allows you to submit JCL for syntax checking only, without executing any of the job steps. This question asks you to identify the standard mechanism for performing that kind of syntax only validation.

Given Data / Assumptions:

• We are working with JCL JOB statements on IBM mainframes.
• We want to check syntax without executing programs or accessing datasets.
• System features for scanning JCL syntax are available.
• We want a method that does not require manual cancellation or hardware interference.

Concept / Approach:
The TYPRUN parameter on the JOB card controls special handling of the job by the system. Setting TYPRUN to SCAN tells the system to read and interpret the JCL, checking for syntax errors and some structural problems, but not to actually run the steps. The job is essentially analyzed and then discarded. This is the standard method for syntax checking in many mainframe environments, and it is much safer and more efficient than running the job and trying to stop it manually.

Step-by-Step Solution:
Step 1: Recall that JOB statements can include parameters such as TYPRUN to describe how the job should be handled. Step 2: Remember that TYPRUN=SCAN is the special value that triggers syntax checking without execution. Step 3: Confirm that this approach aligns with the requirement to avoid running steps while still checking JCL correctness. Step 4: Examine the options and note that option a explicitly mentions TYPRUN=SCAN. Step 5: Discard the other options, which describe impractical or incorrect methods.

Verification / Alternative check:
Mainframe documentation and training materials describe TYPRUN=SCAN as a way to validate JCL. Example JOB cards show //JOBNAME JOB ACCT,CLASS=A,TYPRUN=SCAN,MSGCLASS=X and explain that the system will check the JCL for syntax and output messages without executing any program. This matches the description in option a and confirms its accuracy.

Why Other Options Are Wrong:
Option b suggests physically cutting power, which is dangerous and unrelated to syntax checking. Option c proposes renaming the job card, which does not instruct the system to perform a scan. Option d claims the system cannot scan JCL, which contradicts documented features. Option e misuses SYSIN and DUMMY, which affect data sets, not syntax checking behaviour for the full job.

Common Pitfalls:
Some users forget to remove TYPRUN=SCAN after testing, which leads to jobs that never actually execute. Another pitfall is assuming that syntax scanning will catch all runtime problems; it only verifies structure, not logical correctness or dataset existence. Nevertheless, TYPRUN=SCAN is an important tool for early error detection.

Final Answer:
To check JCL syntax without running the job, you should use TYPRUN=SCAN on the JOB statement so the system scans for errors but does not execute any steps, as in option a.