Debugging Facility (DBUG)

Debugging Facility (DBUG)

When results indicate a problem exists, use the Debugging Facility to examine the logic of programs you have written. The Debugging Facility allows you to test an application program without any preparatory procedure. DBUG intercepts execution of the program at every CA Datacom/DB request. DBUG also displays, among other things, the commands as they are issued and shows the data that is read.

The CA Datacom CICS Services Debugging Facility runs as a subprogram of the application program. DBUG can be used with other diagnostic facilities, such as CA InterTest® for CICS and the CICS online facility EDF. The DBUG transaction controls the scheduling of intercepts, but the intercepted transaction controls the intercept process. The Debugging Facility uses temporary storage and full function BMS (Basic Mapping Support). You can use the Debugging Facility only from a 3270 type terminal that has 80 columns or more, and 24 lines or more. Security for the DBUG transaction is established through standard CICS security features.

The Debugging Facility allows you to examine CA Datacom/DB requests from application programs written in CA Ideal, DMS, Assembler, COBOL, or PL/I using command-level CICS. The application programs can reside above the 16 MB (megabyte) line. The application can use CA Datacom Transparency products and the transparent request is intercepted.

Note: The only value supported by the DBUG transaction for ENTRY: is DBNTRY. Although CA Datacom CICS Services r11 and higher still supports the DATACOM entry point, the DATACOM entry point is not supported by the DBUG transaction. Normal execution occurs for DATACOM calls, but DBUG cannot be used to set up interception points for those calls. For example, if a transaction executes three programs (A, B, and C), where A and B use the DBNTRY entry point to call CA Datacom/DB but C uses DATACOM calls, if DBUG has been used to specify that calls to CA Datacom/DB are intercepted, only calls from programs A and B are intercepted. CA Datacom/DB requests from program C are executed normally but are not intercepted.

Functions of DBUG

The Debugging Facility (DBUG) enables you to accomplish the following tasks:

• Define the interception points for the Debugging Facility
  • Intercept every request issued to CA Datacom/DB before or after execution or both.
  • Limit interception to requests which match criteria you establish.
  • Skip n number of requests.
• While the task is intercepted, you can examine the following:
  • Values of the fields in the CA Datacom/DB Request Area.
  • Program working storage in hexadecimal or character mode.
  • User display associated with this task.
  • Last ten debug panels associated with this task. These can be the last ten requests or other panels viewed and remembered.
  • Data at any address within the CICS region, above or below the line.
  • Entries of the internal CA Datacom/DB trace table.
  • Components of the URT associated with the intercepted task.
• Interact with the application in the following ways:
  • Before execution, modify commands or data by replacing (typing over) data on the display. Suppress execution of a command by changing it to a null operation or change CA Datacom/DB commands.

    Note: Use the correct case when replacing data on the display. Specifically, verify that a replaced DB command is in uppercase. Otherwise, a return code of 05 results in a DC05 abend.

  • After execution, change accessed data or return codes by replacing data on the display.
  • Change program working storage.
  • Switch off Debugging Facility and continue the task or abend the task.
  • Change the interception specification or criteria.

This section contains the following topics:

Using the Debugging Facility

DBUG Panel Format

DBUG Panel Descriptions

DBUG Example - Reviewing an Online Application