The DEBUG-ITEM clause is used to define debugging data items that provide additional debugging information during program execution. This clause is part of COBOL's debugging facility and helps developers monitor program behavior and troubleshoot issues.
DEBUG-ITEM works in conjunction with the debugging facility and debugging mode.
The DEBUG-ITEM clause follows specific syntax patterns and is typically used at the 77 level for independent debugging data items.
123456789101112131415161718192021* Basic DEBUG-ITEM clause syntax 77 debug-item-name DEBUG-ITEM. * Examples 77 DEBUG-VARIABLE DEBUG-ITEM. 77 DEBUG-FLAG DEBUG-ITEM. 77 DEBUG-COUNTER DEBUG-ITEM. * Complete example with data description 77 DEBUG-VARIABLE DEBUG-ITEM PIC X(50). 77 DEBUG-FLAG DEBUG-ITEM PIC X. 77 DEBUG-COUNTER DEBUG-ITEM PIC 9(5). 77 DEBUG-TIMESTAMP DEBUG-ITEM PIC 9(14). * Usage in program PROCEDURE DIVISION. * Set debugging information MOVE "Processing customer record" TO DEBUG-VARIABLE MOVE "Y" TO DEBUG-FLAG ADD 1 TO DEBUG-COUNTER MOVE FUNCTION CURRENT-DATE TO DEBUG-TIMESTAMP
DEBUG-ITEM is typically used at the 77 level for independent debugging items.
| Level | Can Use DEBUG-ITEM | Common Usage |
|---|---|---|
| 01 | No | Record level - not for debugging |
| 02-49 | Rarely | Group levels - uncommon |
| 77 | Yes | Independent items - most common |
| 88 | No | Condition names - different purpose |
123456789101112131415161718* Enabling debugging mode (compiler option) * Compile with debugging enabled * Example: cobc -fdebug program.cob * Runtime debugging activation * Set environment variable or runtime option * Example: COBOL_DEBUG=1 ./program * Program-level debugging declaration PROGRAM-ID. DEBUG-PROGRAM. ENVIRONMENT DIVISION. CONFIGURATION SECTION. SPECIAL-NAMES. DEBUGGING MODE IS ON. DATA DIVISION. WORKING-STORAGE SECTION. 77 DEBUG-VARIABLE DEBUG-ITEM PIC X(50).
DEBUG-ITEM requires debugging mode to be enabled for full functionality.
DEBUG-ITEM is commonly used in specific debugging scenarios where additional program monitoring and troubleshooting information is needed.
12345678910111213141516* Tracking variable values during execution 77 DEBUG-CUSTOMER-ID DEBUG-ITEM PIC 9(5). 77 DEBUG-CUSTOMER-NAME DEBUG-ITEM PIC X(30). 77 DEBUG-PROCESSING-STATUS DEBUG-ITEM PIC X. PROCEDURE DIVISION. * Set debugging information for customer processing MOVE CUSTOMER-ID TO DEBUG-CUSTOMER-ID MOVE CUSTOMER-NAME TO DEBUG-CUSTOMER-NAME MOVE "PROCESSING" TO DEBUG-PROCESSING-STATUS * Process customer record PERFORM PROCESS-CUSTOMER * Update debugging status MOVE "COMPLETED" TO DEBUG-PROCESSING-STATUS
DEBUG-ITEM can track variable values throughout program execution.
12345678910111213141516171819* Monitoring program execution flow 77 DEBUG-CURRENT-PARAGRAPH DEBUG-ITEM PIC X(30). 77 DEBUG-EXECUTION-COUNT DEBUG-ITEM PIC 9(5). PROCEDURE DIVISION. MOVE "MAIN-PROCESS" TO DEBUG-CURRENT-PARAGRAPH ADD 1 TO DEBUG-EXECUTION-COUNT PERFORM PROCESS-DATA MOVE "VALIDATE-DATA" TO DEBUG-CURRENT-PARAGRAPH ADD 1 TO DEBUG-EXECUTION-COUNT PERFORM VALIDATE-DATA MOVE "WRITE-RESULTS" TO DEBUG-CURRENT-PARAGRAPH ADD 1 TO DEBUG-EXECUTION-COUNT PERFORM WRITE-RESULTS
Track which paragraphs or sections are being executed.
1234567891011121314151617* Tracking error conditions and status 77 DEBUG-ERROR-CODE DEBUG-ITEM PIC 9(3). 77 DEBUG-ERROR-MESSAGE DEBUG-ITEM PIC X(50). 77 DEBUG-ERROR-LOCATION DEBUG-ITEM PIC X(20). PROCEDURE DIVISION. * Normal processing MOVE 0 TO DEBUG-ERROR-CODE MOVE SPACES TO DEBUG-ERROR-MESSAGE * File processing with error handling OPEN INPUT CUSTOMER-FILE IF FILE-STATUS NOT = "00" MOVE FILE-STATUS TO DEBUG-ERROR-CODE MOVE "File open failed" TO DEBUG-ERROR-MESSAGE MOVE "FILE-OPEN" TO DEBUG-ERROR-LOCATION END-IF
Monitor error conditions and their locations in the program.
Following these best practices ensures effective use of the DEBUG-ITEM clause for program debugging and monitoring.
| Pitfall | Problem | Solution |
|---|---|---|
| Overuse in production | Performance degradation | Use conditional compilation or separate versions |
| Insufficient debugging info | Inadequate troubleshooting data | Plan debugging strategy carefully |
| Forgetting to enable debug mode | No debugging information captured | Ensure debugging mode is properly enabled |
| Poor naming conventions | Confusing debugging output | Use clear, descriptive names |
| Not documenting usage | Difficult to understand debugging output | Document all debugging items and their purpose |
| Use Case | DEBUG-ITEM Suitability | Reasoning |
|---|---|---|
| Development testing | Excellent | Essential for troubleshooting during development |
| Complex program logic | Good | Helps track complex execution paths |
| Error investigation | Good | Provides detailed error context |
| Production monitoring | Poor | Performance impact outweighs benefits |
| Simple programs | Poor | Unnecessary overhead for simple logic |
| Usage | Syntax | Example |
|---|---|---|
| Basic debugging item | 77 debug-name DEBUG-ITEM | 77 DEBUG-VAR DEBUG-ITEM |
| With data description | 77 debug-name DEBUG-ITEM PIC... | 77 DEBUG-VAR DEBUG-ITEM PIC X(50) |
| Multiple debug items | Multiple 77 items with DEBUG-ITEM | 77 DEBUG1 DEBUG-ITEM 77 DEBUG2 DEBUG-ITEM |
| Variable tracking | 77 debug-name DEBUG-ITEM PIC 9(n) | 77 DEBUG-COUNT DEBUG-ITEM PIC 9(5) |
| Status tracking | 77 debug-name DEBUG-ITEM PIC X | 77 DEBUG-STATUS DEBUG-ITEM PIC X |
1. What is the primary purpose of the DEBUG-ITEM clause in COBOL?
2. At what level is the DEBUG-ITEM clause typically used?
3. What debugging information can DEBUG-ITEM provide?
4. When is DEBUG-ITEM most useful?
5. How does DEBUG-ITEM relate to the DEBUGGING MODE?
Understanding the DEBUGGING MODE for program debugging.
Complete guide to data definition in COBOL.
Using DEBUG-ITEM in working storage.
Understanding COBOL program organization.
Using DEBUG-ITEM for error tracking.