Development of Local Cobol Programs2789

Development of Local COBOL ProgramsConnecting to a z/OS host from the workbench
Module 4 - Development of Local COBOL Programs
Ed Steele – Version 1, 06/23/2009
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Thanks to the following individuals, for assisting with this course:
Russ Courtney/IBM
Reginaldo Barosa/IBM-Rational
David Bean/IBM-Rational
Ed Steele/IBM-Rational
Dave Willsey/IBM-Rational
Audience
This course is designed for application developers who have learned or programmed in COBOL, and who need to do z/OS Traditional Development and Maintenance as well as build leading-edge applications using COBOL and Rational Developer for System z.
Prerequisites
This course assumes that the student has a basic understanding and knowledge of software computing technologies, and general data processing terms, concepts and vocabulary, as well as a working knowledge of COBOL and z/OS.
Knowledge of SQL (Structured Query Language) is assumed for database access is assumed as well.
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Course Name: Rational Developer for System z Foundation Training
Course Description: Learn how to use Rational Developer for System z to do z/OS traditional development, maintenance, support and for Enterprise Modernization of z/OS applications
Pre-requisites: Some experience developing COBOL applications using z/OS is expected. A working knowledge of SQL is also recommended.
Course Length: ~5days – or if done in self-paced mode, at your own pace
Topics (Agenda)
Getting Started - installing and configuring RDz - and the course materials, and using Eclipse
The RDz Workbench
Code analysis tools
Modifying test data
Connecting to a mainframe
Debugging z/OS Applications
Debugging Batch Applications
Working with File Manager
Creating Fault History views
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Define the steps in a generalized methodology of ABEND resolution
List the various sources of ABEND inputs, including:
PD Tools documents
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ABEND Overview
When an application ABEND (ABnormal END-of-job) occurs, z/OS stops executing your program, closes files and buffers and generates a single high-level message in the form of a System Completion Code (Sxxx).
The System Completion Code is usually written to an output listing file through your //SYSOUT DD * JCL entry.
This completion code indicates why the system has decided to stop executing your application.
It is related to, but often only loosely related to what is really wrong with your application
Because of this the System Completion Code represents the starting point for your analysis of the problem.
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Debugging Assistance
Along with the System Completion Code, using IBM’s Problem Determination tools (PD Tools) Fault Analyzer you can obtain various reports which describe What/Where and How the ABEND occurred.
Valuable information contained in the Fault Analyzer report-files includes:
The System Completion Code (and often a short text description of what it designates)
A short explanation of the cause of the ABEND
The COBOL instruction (statement) or line number, which contained the invalid operation causing z/OS to halt execution
Variables of interest – and code surrounding the instruction that halted execution
A "core-dump" (a hexadecimal printout) of the internal machine storage and registers relevant to the areas of your program surrounding the COBOL instruction which caused z/OS to halt execution.
This information is critical to begin understanding and researching the problem, but it is sometimes insufficient to solve the underlying application problem, which could be any combination of:
Incomplete, incorrect or invalid COBOL procedural logic
A typo such as a misplaced period, or incorrectly specified field
Incorrect or invalid input data
Batch jobs run out of sequence
Input files missing or corrupted (hardware errors)
Errors which relate to JCL problems
etc.
Getting Started
There are as many different ways to analyze and research COBOL ABENDs as there are individual approaches to writing procedural logic. However, if you've never done software production support work, consider starting with the following structured problem-solving approach:
Preparation
Research
Hypothesis
Solution
Resolution
As a final note before we begin discussing the above, understand that there are often two distinct phases of application Production Support:
1. Data Center “on-call” ABEND resolution - wherein a technician receives notification that a job or transaction has ABEND’d and must be "fixed" within an extremely short timeframe (usually minutes to hours). In this case, the technician's main concern is to "patch" the problem - get the system back online, or get the batch job-stream back into production ("Patch-It").
2. NextDay problem resolution - wherein technician(s) actually track down and solve the problem that caused the ABEND ("Fix-It").
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1. Preparation and Information Gathering – 1 of 2
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Start with Fault Analyzer's reports – as they contain a broad and deep set of formatted, structured, analysis information
Collect additional supporting ABEND output (SYSOUT) from the job, DISPLAY statements, etc.)
Obtain copies of the run-time:
JCL
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1. Preparation and Information Gathering – 2 of 2
If batch, from the JCL learn the dataset names of input and output files
accessed by the program (which you may need to browse as part of your research)
Learn the nature of the batch job from system documentation, or from an application business expert (at least at the level of module-flow and file-access)
RAA Batch Job Diagram
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Research – Analyze the Gathered ABEND Data
From the preparation step, construct a mental map (understanding) of the program's execution (HOW the ABEND occurred - which will start you down the path of research to understand "WHY" the ABEND occurred
WHY determination usually requires a combination of "Static" and "Dynamic" analysis - complementary research and investigative approaches.
These steps need not be followed in this order. Rather, in time you will develop an "intuition" as to which kind(s) of analysis will be most likely to provide the information you need to solve your problem.
To assist, you can use application research and analysis tools such as
IBM’s Rational Asset Analyzer, Rational Developer for System z – Static Analysis
IBM's Debug Tool or CICS I.A. – Dynamic Analysis
So – if the reason "why" the ABEND occurred is not apparent at this point, perform Static and/or Dynamic Analysis on the specific areas of the application relating to the ABEND.
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Static Analysis – Overview of Techniques
1. Structural Visualization: is the generation of an accurate mental map, understanding or mental image of the program's control structure, or logic-architecture. Using the starting point represented by the ABEND condition (the statement which caused z/OS to halt execution) and using electronic-assisted tools (such as IBM’s Rational Asset Analyzer or Rational Developer for System z), build an accurate understanding of the code invocation at:
The module/file level (System View) - Paragraph/Section level (Hierarchy chart) - Statement level (Flow chart)
Structural Visualization can done be "top-down", by asking open-ended questions; such as learning how a particular routine "hangs-together logically", or it can be used "bottom-up", by asking specific close-ended questions about a program, such as "How does this particular paragraph get executed?" "How did this module get invoked?"
2. Data Flow Analysis: A combination of control structure analysis and data item analysis, which seeks to determine the usage of particular fields throughout a program. Data flow analysis is used to determine (from a given instance of a data item) where the next occurrences of that item exist in your program, and how the data item is used; (as a receiving field in a MOVE or mathematical operation, as the sending field in a MOVE statement, as part of a logic-branch (IF, PERFORM UNTIL/VARYING, etc.).
3. Data Impact Analysis: An expansion of Data Flow Analysis which traces the movement of data from field-to-field throughout a program, or throughout an entire application; including I/O (screens and files). Using Data Impact Analysis, you can identify all fields that might have had an impact on the contents of a field (before the ABEND occurred). And just as importantly - you can learn the affect changing this field will have on the behavior of the application.
4. Textual or Data Item Usage: Utilized more for application maintenance and enhancement requests, this type of Static Analysis involves searching for "categories" of program-items, such as "List all fields that contain *JUL*, *GREG*, *YR*, *YEAR* (suspect date candidates for Year2000 conversion), or list all such fields with two digits (numeric) or two-byte (alphanumeric) definitions.
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Dynamic Analysis – Overview of Techniques
1. Tracing: Source-level interactive debugging. Watch the program execute statement-by-statement, and line-by-line. This is very useful for detailed-debugging, particularly of dense or complex instructions. Some software (for example, the Rational Developer for System z) allows you to trace the program logic, attempting to re-create the sequence of events (COBOL statements) that transpired up to and including the ABEND condition. Tracing is an invaluable method for detailed debugging. However, given the size and scope of production applications, it is generally more practical to trace specific problem areas of a program.
2. Interactive Execution: Execute (run) a program, stopping at selective Breakpoints (Pause execution each time a certain field-value changes, or when a value exceeds some threshold), and examining the contents (value) of specific fields. Interactive Execution must be done by (or with) an application analyst who understands how the system is supposed to operate. Interactive Execution is useful for observing control flow, and is often combined with line-by-line tracing by setting selective breakpoints, monitoring values, "running" the application to the breakpoints, and then tracing the code line-by-line.
3. Selective Data State Collection: Execute code and establish a functional summary of specific data states that it creates. Use these states in subsequent test runs to compare results of current values to expected values.
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Hypothesis - Determine WHY the ABEND occurred – 1 of 3
Your preparation and research is probably all you need to be able to describe WHAT, WHERE and HOW the ABEND occurred
At what point in the program the logic failed, and what sequence of COBOL statements caused the failure).
However, before modifying any logic, you must determine WHY these statements (or sequence of events) caused this particular failure
"Why did this production input file contain spaces in a numeric field?"
"Why did the program's logic perform the Initialization routine twice?"
"Why did the Read routine execute past end-of-file?"
etc.
Only through a determination of WHY will you be able to make a change to production business logic safely, and with confidence that;
Your change will resolve the ABEND
Your change will not introduce new (additional) ABENDs
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Sometimes it is relatively easy to come to an understanding of WHY certain ABEND conditions occurred. For example, perhaps a period was left off the appropriate termination point for an IF statement - which caused execution to perform an operation out of sequence. Or perhaps an IF .. NUMERIC test (which should have been coded for all numeric fields in a file) was forgotten. Or a paragraph was performed through the wrong paragraph-exit, or a production job was released before certain files were available (causing I/O errors). These types of ABEND situations can be understood (and usually resolved) fairly quickly. But, not always.
What if - in the case of the IF statement with the incorrect termination point - the logic that has been coded, correctly processed the first 100,000 records in the file?
Making a change to a critical IF condition could very well affect other down-stream processing within the program, wrecking havoc with subsequent routines.
Or what if - in the case of the file containing blanks in the numeric fields - the input file was supposed to be "clean" (validated) by this point in the job-stream - having gone through allegedly "exhaustive" edits in prior modules.
By simply adding an IF test you may solve your program's specific ABEND, but you will not have resolved the actual problem - which exists somewhere else in the system.
In other words, localized/piecemeal approaches to resolving production ABENDs are not recommended - as they usually change the problem, instead of solving it. And sometimes they just spawn new problems.
It should be noted that, a clear understanding of the business functionality automated by this process is usually required to resolve WHY something has gone wrong.
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Developing a clear and accurate determination of WHY a problem that lead to an ABEND condition exists may take a considerable amount of time, depending on the:
Size, complexity and structure of the code
Your familiarity with the program's business purpose - coupled with your ability to grasp the point of each statement (assuming you didn't write the code)
Type of ABEND and reason for the problem (some are more diabolical than others)
Size of the input/output files, and capabilities of your file editor
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Solution - Fix the Problem and Test Your Solution
Take the appropriate action to resolve any business - or system-wide issues.
Depending on how extensive the damage caused by the problem, or for how long any problems have persisted undetected:
Files may have to be restored from backups from a previous point-in-time
Jobs may have to be re-run from a previous point-in-time (synchronized with file generations)
Files may have to be modified with "one-shot" programs, written to resolve issues that require "surgery" on the data
Take the appropriate action to fix the technical (coding) problem:
Edit program source - modifying the existing production logic …and/or…
Modify the JCL (if the error included JCL issues)
You may have to edit files using File Manager
Test your solution:
Compile and Link the new version of the application
Create an "image copy" of the production file system, in order to test your fix
Re-Run the batch job and analyze results

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Migrate changes to back in to production
Promote your changes to production
Schedule and re-run the cycle
After having completed this unit on Production Support/Application Testing/Software Defect and IBM Mainframe COBOL ABEND Research, you should now be able to:
Define the steps in a generalized methodology of ABEND resolution
List the various sources of ABEND inputs, including:
PD Tools documents
Fault Analyzer reports
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ABEND Completion Codes and some typical causes
While there is a wide variety of reasons for ABEND conditions ("WHYs") in production systems, it is possible (and useful) to categorize and organize HOW certain conditions often lead to certain types of ABEND completion codes - in order to expedite or streamline your analysis and research (an 80/20 approach to analysis).
The following information on a few common z/OS ABEND completion codes, and the conditions which generated them is included for you to make effective use of PD Tools/Fault Analyzer listings and the above debugging, research and analysis process.
Notes:
This information is available to some degree within the RDz product in the Lookup View
There is another source of ABEND/Debug information you might want to take a peek at:
Reason(s)
S001-0: Conflict between record length specifications (program vs. JCL vs. dataset label)
S001-2: Damaged storage media or hardware error
S001-3: Fatal QSAM error
S001-5: Attempt to read past end-of-file
Instructions:
S001-3: Internal z/OS problem
S001-4: Forgot to code BLOCK CONTAINS 0 RECORDS in FD (default Block is 1)
S001-5: Logic error (either forgot to close file, or end-of-file-switch not set, overwritten or ignored)
Tools to debug/RDz equivalent return codes:
S001-0: Cannot occur on RDz with Local ASCII/Windows (Line Sequential) files
S001-2: Norton Utilities – if on Workstation/COBOL application
S001-4: Cannot occur on Workstation/COBOL (no blocking for Line Sequential files)
S001-5: Logic error: Use RDz's Perform Hierarchy or RAA's Program Flow Diagram to detect
Dynamic:
S001-0: During Debug – set a Watch Monitor on the 01 record
S001-2: Need to have PC/IT technician investigate (may need to reformat disk)
S001-4: Always code BLOCK CONTAINS 0
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Reason(s)
S013-10: Dummy data set needs buffer space; specify BLKSIZE in JCL
S013-14: DD statement must specify a PDS
S013-18: PDS member not found
S013-1C: I/O error search PDS directory
S013-20: Block size is not a multiple of the LRECL
S013-34: LRECL is incorrect
S013-50: Tried to open a printer for Input of I/O
S013-60: Block size not equal to LRECL for unblocked file
S013-64: Attempted to Dummy out indexed or relative file
S013-68: Block size > 32K
S013-A8: Invalid RECFM for SYSIN/SYSOUT
S013-D0: Attempted to define PDS with RECFM FBS or FS
S013-E4: Attempted to concatenate > 16 PDSs
Instructions:
Frequent Coding Causes:
Most of these ABENDs occur running und z/OS (some may not even occur under z/OS, although older modules running OSVS or VS COBOL II code that have not been recompiled can produce them). Most are due JCL/COBOL FD inconsistencies.
Tools to debug:
Static
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- SYSOUT DD statement missing
- The value in an AFTER ADVANCING clause is < 0 or > 99
- And Index or Subscript is out of range
- An I/O verb was issued against an unopened dataset
Instructions:
OPEN, CLOSE, READ, WRITE, Table handling routines
Note also that during Debug SYSOUT-DISPLAYs are written to the "console", recall how to view
- Incorrect logic in setting AFTER ADVANCING variable (or failure to understand 0-99 limits)
- Incorrect logic in table handling code, or number of table entries has outgrown PIC of variable (e.g. PIC 99, but 100 entries)
Tools to debug:
Static
SYSOUT problem: Open multiple windows on RAA Batch Job Diagram and program Environment Division - SELECT ASSIGN.
In RAA: Double-click on GO TO verb, or PERFORM chain, or paragraph name.
In RDz: Select Paragraph name/Perform chain and select: Open Declaration
Dynamic:
Set Watch Breakpoint and Monitor on table index or AFTER ADVANCING variable.
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Reason(s)
The program is attempting to access a memory address that is not within the applications z/OS Address Space
- JCL DD statement is missing or incorrectly coded
- Incorrect logic in table handling code (referencing a table subscript < 1 or > max-table-size),
- Number of table entries has outgrown PIC of variable (i.e. PIC 99, but 100 entries).
- In IMS/TM systems, an MFS LL (length) field value is smaller than the actual input MSG length.
Tools to debug:
Static
- DD statement problem: Open multiple windows on RAA Batch Job Diagram and program Environment Division - SELECT ASSIGN
- IMS LL problem: Analyze through multiple Edit Windows (same solution as DD).
- Incorrect linkage problem:
- Open multiple windows on CALLing and CALLed programs - verify linkage declarations.
Dynamic
- Set conditional advanced break point on subscript (i.e. IDX < 100).
RAA - Utilize Run-Unit View to view all modules in Debug run-stream (both active and inactive).
Incorrect logic
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Instructions:
Arithmetic, IF-THEN-ELSE, MOVE (if receiving field is numeric - )
Note: RDz will also S0C7 if sending field is numeric and contains non-numeric (MOVE pic9field TO picXfield)
- Incorrectly initialized, or uninitialized variable
- Missing or incorrect data edit
- 01 to 01 level MOVE if sending field is shorter than receiving field
- Move of Zeros to Group-level numeric fields
- MOVE CORRESPONDING incorrect
Tools to debug:
RAA report with options data selector on MOD or ALL
Dynamic
Run through to S0C7.
Solutions:
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Instructions:
- Incorrectly initialized, or un-initialized variable
- Missing or incorrect data edits (i.e. failed to check divisor for zero value)
Tools to debug:
Static
RAA report on all DIVIDE and COMPUTE instructions – or using RDz double-click on these verbs and select Filter from the Context Menu
Dynamic
Locate to field definitions of the offending fields
Solution:
IF divisor > ZERO
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Reason:
Timeout due to program logic caught in "loop" through instruction set with no exit.
Note: RDz Workstation binaries (Run-Time System) does not honor the concept of timeout.
- Invalid end-of-file logic
- End-of-file switch overlaid
- Subscript not large enough
- Perform Thru wrong Exit
- PERFORM UNTIL "End-Of-File", but not performing "READ" routine to reach EOF condition
Tools to debug:
RAA Display Perform Thru
Analyze counts (color)
Set an Advanced Break Point - Conditional on count
Solution:
From within Debug, use RAAi to identify logic which could cause looping.
Select and click on PERFORM THRU, PERFORM UNTIL, GO TO.
Place break points on potential error lines.
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Reason:
CALL made to program which could not be located along normal search path
(STEPLIB top-to-bottom, JOBLIB top-to-bottom, LINKPACK)
Instructions:
- Module name spelled incorrectly
- STEPLIB does not contain load library with module
- I/O error occurred while z/OS searched the directory of the library
Tools to debug:
Dynamic
Set Program Advanced Break Point (Entry) to set program break before entry to system.
Solution:
D37: Primary space exceeded, no secondary extents defined.
E37: Primary and secondary extents full. In TSO, PDS directory needs compress.
E37-04: Disk volume table of contents (VTOC) is full.
Reason:
MVS could not find space for output WRITE.
Note: RDz Local COBOL Run-Time System does not honor the concept of Primary/Secondary space "Out of space" condition will not occur until disk actually fills up
Instructions:
WRITE
- Not enough space initially allocated to output file(s).
- (more likely) Logic error - program in (infinite) loop writing output file(s) - see S222/S322 reasons.
Tools to debug:
Static - if (unlikely as this may be) you're debugging locally (on your Workstation) you can find the out-of-space file and statistics on it as follows:.
Do directory list on the file you are writing to:
Go to DOS Window
Type "DIR fname.ext"
On the host the JCL will show the DDNAME and z/OS filespec of the dataset in question
Dynamic
Set an advanced conditional break point to break on a certain number on iterations
See S222/S322 reasons and solutions
Also, set break point on file WRITE statements
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Database Abends
DB2 application access rarely abends, they "die gracefully" due to return code processing.
DB2:
SQLCODE
A unique integer which describes DB2's reaction to your request.
SQLCA
A large 01 block, which contains several other fields pertinent to debugging, particularly the SQLWARNs.
Suggestion:
Set Line Breakpoint and/or Variable Monitor on SQLCODE and other key feedback areas
- or -
Double-click on field, Ctrl/F3
Notes on UDB Offloading and Database Abends
UDB handles SQLCODE processing in a manner consistent with DB2. However, it should be noted that UDB does not handle SQLWARNO-n and the SQLCA (SQLERRD, etc.) fields compatibly.
DB2 ABENDs
If DB2 tables have not been defined, you may get a -204 return code on your SQL statement.
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Topic Considerations
Note: In this topic you will learn how to use Fault Analyzer to debug an ABEND. The screen captures all describe connecting to a public z/OS machine that IBM makes available – during classes.
If you are taking this course through standard IBM services delivery you should be able to use the properties (I/P address, port#s, etc.), logon IDs and passwords that your instructor provides you with.
But you may also be taking this course standalone – and in that case, you will need to speak to your company's Systems Programming staff to learn how to connect and logon.
It goes without saying that the actual file names in the screen captures of mainframe libraries and datasets will vary. So you should focus on the process and steps and "how to" – and don't be perplexed at differences in screen captures.
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Work with ABEND analysis reports created by IBM Fault Analyzer
Browse Report and Mini-Dump pages
Retrieve various Fault Analyzer view information
Browse and search ABEND codes
Use the various productivity features in the Fault Analyzer perspective
Note:
This presentation and Lab is not a comprehensive IBM Fault Analyzer unit. It is only intended to introduce you to the RDz/Fault Analyzer interface. It is assumed that you are already working with IBM Fault Analyzer on the z/OS host.
Connecting to a z/OS host from the workbench
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Face facts:
ABEND research ("shooting a dumps") is not how you want to spend your week-nights
The good news? You don't have to.
Fault Analyzer:
Variables and variable values
Data and buffers
Gives you a serious head start on the What/Where and How of ABEND debugging
The z/OS-based debugging engine is provided by the IBM Debug Tool for z/OS product. It runs on the z/OS.
"Perspectives" - Recall that a "Perspective" is a convenient grouping for a collection of views organized around a given role or task
So far in this class, you've used the:
z/OS Projects Perspective – to develop local COBOL applications
Data Perspective – to develop local COBOL applications
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What is Fault Analyzer?
IBM Fault Analyzer is a tool that helps you determine the cause of an application ABEND. It is used to determine:
What happened, how it happened, what program, what line/statement, which variables, what files, were involved, etc.
Fault Analyzer provides the necessary information to perform root cause analysis on an application ABEND.
You do not have to interpret low-level, system dumps and wade through HEX data. Information is presented in report format
IBM Fault Analyzer for z/OS® gathers information about an application and the surrounding environment at the time of an abnormal end (ABEND), providing you with the valuable information you need to work through
After analyzing information about your application and its environment, Fault Analyzer generates an analysis report (IDIREPORT) that describes the problem in terms of application/program statements and variables
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Fault Analyzer for z/OS Overview
Fault Analyzer is part of IBM’s Problem Determination Tool family of products: http://www-01.ibm.com/software/awdtools/deployment/
It runs in both test and production with very little overhead, and:
Provides support for analyzing***:
IMS and CICS® online application and system failures - with debugging facilities for all of the IBM-mainstream online files and databases
IMS-DL/I, DB2, VSAM, IDMS, etc.
WebSphere® Application Server for z/OS system failures
WebSphere MQ application failures
Batch (QSAM/VSAM/DB2®) application failures
Helps you analyze failures when they occur or reanalyze them after the fact
Expands error messages and codes that apply to your failure with interactive reanalysis and includes a feature for using application-specific messages and codes to supplement those supplied by IBM
Creates a fault history file with an interactive display that helps you track and manage application failures
Starts automatically when an application fails, eliminating the need to recompile programs or change the job control language (JCL)
Integrates with Rational Developer for System z enables developers to diagnose application problems without changing user interface
For Fault Analyzer product information, see: http://www-01.ibm.com/software/awdtools/faultanalyzer/
***See Notes
Fault Analyzer for z/OS supports applications running under z/OS and OS/390 in the following environments:
COBOL
PL/I
Assembler
C/C++
Java
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Fault Analyzer – Operational Process
The purpose of Fault Analyzer (FA) is to determine the cause of any ABENDs in an application program.
You do not have to read through application or system dumps, because the product has the ability to isolate the exact instruction that caused a particular error.
The Analysis engine provides automatic analysis when the application fails.
When an ABEND occurs, Fault Analyzer activates automatically, and then records details in a fault history file (see screen capture below)
Fault History files contain information about the faults analyzed by Fault Analyzer for z/OS.
Using Fault History files, re-analysis is available when real-time ABEND analysis isn’t enough (you can extract additional information in batch or interactive mode)
ABEND happens
Salient details (points of interest) written and stored
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Fault Analyzer
An IDIREPORT is produced that provides ABEND analysis information
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Reviewing ABENDs in the Fault Analyzer Perspective
Besides the IDIREPORT, you may also wish to use RDz's Fault Analyzer perspective, to analyze and debug an ABEND situation.
To do that you'll need to:
Switch to the Fault Analyzer perspective in RDz
Specify the history file to connect with, that populates a Default ABEND view with failed online and batch job IDIREPORTs and other outputs
Learn how to navigate the Fault Analyzer perspective, to make use of the information contained therein
The next slides contain the step details
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Steps:
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2. Enter: FAULTANL.<version>.HIST
Ex. FAULTANL.V10R1.HIST
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Content Area shows Fault Analyzer IDIREPORT – detailed information on ABEND
IDIREPORT
Additional Fault Analyzer views exist for other ABEND documentation including history data
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From the Default tab
Scroll up and down – to find a particular ABEND
Double-click an ABEND history file, to bring up its IDIREPORT and other stats
Sort the list by any of the column headings
Can also work with options of the Context Menu – with each ABEND entry
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Fault Analyzer – Browse Report – S0CB
The IDIREPORT presents a formatted, high-level summary of the points of interest necessary to debug ABEND conditions in your application.
Specifically, to answer the questions:
What happened?
How did it happen?
Program line where the S0CB occurred

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Fault Analyzer – Browse Report – S0C4
Here's an example of an IDIREPORT which shows that RPT-REC is
"not addressable"
…which is a euphemism for: "There's something really wrong with the file/FD/JCL DD connection"
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The IDIREPORT and supporting text varies from ABEND to ABEND depending on:
Type of ABEND
Run-time platform
Note:
CUST-ACCT-BALANCE's value is shown in hex (as it represents invalid data)
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A S0C9 is like a S0CB (divide by zero) except that a S0C9 occurs because of an excessively large fixed-point number obtained as the result of a decimal division operation
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Here is information on an IMS (DL/I) S0C1 ABEND
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IDIDREPORT information on a module-not-found (S806) ABEND
Most likely SAM2 is either a typo, or
the program did not successfully compile/link into the Load Module
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The Lookup view shows a great deal of background information on:
ABEND codes
DB2 SQLCODE
etc.
You can use the view, or double-click on the ABEND code shown in the IDIREPORT
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Fault Analyzer Integration – Mini-Dump Reading 1 of 2
Fault Analyzer also provides for the reading/browsing of System Dump data – in Hex/Character format.
Select an ABEND
Scroll through the dump – Issue navigation commands: Show nnn, +nn, etc.
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1. Right-click over the storage address
2. Add your note (click OK)
3. Your note becomes highlighted text inside the dump
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1
2
3
Define views which contain a set of history files.
Display fault entries from all history files as if they were in one dataset.
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A History File
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Available Line Commands
Batch and/or Online may be in the same list
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What RDz Perspective is used to view Fault Analyzer reports?
How does RDz obtain Fault Analyzer Information? Where does the information originate?
RDz Fault Analyzer interface has a Lookup View. What is it used for?
How can you jump to the program statement where the ABEND occurred with the RDz Fault Analyzer interface?
The Fault Analyzer Perspective
Fault History File (Add New, Fault History file). It originates when a program abend occurs on the host. The complied source is saved in PDS and matched against the Fault History file to obtain the program statement (line number) where the abend occurs.
The Lookup View is used to search / look up the abend code. For example, what is a SOC4, SOC7, etc.....
If the correct LANGX file was available during the real-time analysis, you can click on the line number to jump to the source of the abending program.
Checkpoint Solutions:
2. In the Remote Systems view, under New Connection:
i. Click the ‘+’ in front of z/OS …
ii. Right-click z/OS … then select New Connection from the pop-up dialog
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Having completed this unit, you should now be able to:
Work with ABEND analysis reports created by IBM Fault Analyzer
Browse Report and Mini-Dump pages
Retrieve various Fault Analyzer view information
Browse and search ABEND codes
Use the various productivity features in the Fault Analyzer perspective
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In this workshop you are going to:
Copy a several datasets from your instructor's zServerOS TSO ID to your ID
Details on the next slide
Modify JCL dataset names (and high-level qualifiers) to match your Sandbox ID
Compile a program named: HOSPCALC – which contains different types of COBOL ABENDs generated from invalid COBOL logic in different parts of the program
Run HOSPCALC (it will ABEND) – and from the Fault Analyzer IDIREPORT:
Find the error in the COBOL source, and use the IDIREPORT ABEND analysis data to fix the error
After you've solved the problem, you will save your edits, and re-compile HOSPCALC. Then run the program until you either get the next ABEND … or get a zero return code
HOSPCALC
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If you are working on the Sandbox, do the following:
In Remote Systems, create a new MVS Filter named: RDZFA for: DDS0001.POT.*
Expand the RDZA filter, and:
Copy DDS0001.POT.COBOL member: HOSPCALC to <EM4Zxx>.POT.COBOL PDS
Copy DDS0001.POT.JCL member: HOSPCALC to <EM4Zxx>.POT.JCL PDS
This is the compile JCL for HOSPCALC
Copy DDS0001.POT.JCL member: HOSPCRUN to <EM4Zxx>.POT.JCL PDS
This is the run JCL, for HOSPCALC
Right-click over DDS0001.POT.DATA and use Allocate Like to create a new PDS named: <yourEM4Zxx>.POT.DATA - with the same dataset characteristics
Example with ID: EM4Z07
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Edit HOSPCALC.
Save your edits
Save your edits
5. Submit your modified HOSPCALC JCL. When the job finishes, check the results in your JES My Jobs filter (it should compile successfully – but check that the LKED step ran)
6. Submit your modified HOSPCRUN JCL. The job should ABEND. In JES - My Jobs, view the IDIREPRT step, to see the specific system completion code and surrounding Fault Analyzer ABEND analysis information
Note that HOSPCALC contains four separate ABEND errors – that you will hit, one at a time: an 0C7, an 0CB, an 0C4 and a combined 0C7/0C4 ABEND (Sounds strange ... Essentially Fault Analyzer will find two different problems on one statement)
The comments and descriptions in the IDIREPRT combined with your COBOL knowledge should be sufficient to debug and fix these problems, but feel free to elicit help from your instructor if you're stuck.
7. Fix the COBOL error that caused the ABEND. Then repeat steps 5 and 6 until you find and fix all of the ABENDs in HOSPCALC. You're done when HOSPCRUN finishes with a zero return code.
However – If you need any help, from within edit on HOSPCALC, do a Find ALL on: *RDZ

Documents

Development of Local Cobol Programs2789