In a CICS program, which EXEC CICS command is used to obtain the user logon id associated with the current task?

Introduction / Context:
Many CICS applications must know which user is signed on in order to perform security checks, maintain audit trails, or personalize behavior. CICS stores user identification information as part of the task environment, and it provides commands that allow application programs to retrieve this information. This question asks specifically which command is used to obtain the user logon id for the current task.

Given Data / Assumptions:

• Users log on to CICS using signon transactions such as CESN.
• CICS associates a user id with each authenticated session and task.
• Application programs may need to examine this user id in their business logic.
• The EXEC CICS ASSIGN command can return several pieces of task related information.

Concept / Approach:
The EXEC CICS ASSIGN command is a general purpose command that retrieves environment information about the current task, including transaction id, terminal id, and user id. By specifying the USERID option and a receiving data area, the program instructs CICS to copy the user logon id into that field. The program can then use this value for logging, authorization checks, or other logic. This approach is standard across many releases of CICS and provides a consistent way to access user information.

Step-by-Step Solution:
Step 1: Recognize that CICS must have an API that returns environment and task information to programs. Step 2: Recall that EXEC CICS ASSIGN is the command used for retrieving task related attributes such as USERID. Step 3: Specify USERID and a COBOL data area in the ASSIGN command so CICS can place the logon id value there. Step 4: Use the returned user id in authorization logic or audit records as required by the application.

Verification / Alternative check:
Examples in CICS programming guides often show code fragments such as EXEC CICS ASSIGN USERID to a data field, followed by business logic that checks the user against allowed roles. There is no similar capability documented for ENQ, RETURN, or HANDLE CONDITION, which confirms that ASSIGN USERID is the correct way to retrieve the logon id in an application program.

Why Other Options Are Wrong:
Option B is wrong because ENQ relates to resource locking, not user identification. Option C incorrectly claims that RETURN places the user id into EIBRESP, but EIBRESP contains response codes for CICS commands. Option D misuses HANDLE CONDITION, which deals with exceptional conditions, not user ids. Option E is incorrect because CICS clearly offers ASSIGN USERID for this purpose.

Common Pitfalls:
Developers sometimes hard code user ids or pass them through COMMAREA instead of using ASSIGN, which can lead to inconsistencies if sessions change. Another pitfall is assuming that every task has an authenticated user id, which may not be true for certain system tasks. Proper coding checks for the presence and content of USERID before relying on it for authorization. Knowing that EXEC CICS ASSIGN USERID is the correct mechanism helps standardize user identity handling across CICS applications.

Final Answer:
EXEC CICS ASSIGN USERID into a specified data area returns the user logon id associated with the current CICS task