AVOIDING DATASET TRIGGERING IF SPACE ABEND (ABENDB37) ON TRIGGER DATASET

Resolving The Problem

TWSz dataset triggering is based on monitoring the SMF14/15 records for DATASET CLOSE. These records are created immediately when the dataset closes, independently of STEP END when the third (abnormal termination) keyword of the DISP= parameter is processed.

Although there is no way to prevent DATASET TRIGGERING from adding the application into the Current Plan when the trigger dataset is deleted at STEP END of the creating jobstep, the following technique will avoid incorrect processing. This is done using JOBSTEP CONDITIONAL DEPENDENCES, and all processing is within TWSz. No modification is required of any processes outside of TWSZ -- including the job or started task which creates the triggering dataset.

To accomplish this, define the ETT-added application as follows:
1. The first operation is a BATCH TSO job to check whether the dataset exists:

//FILETEST JOB (),'OPCTEST',CLASS=A,MSGCLASS=X,    
//             MSGLEVEL=(1,1),NOTIFY=ATKNSN2        
//*      
//*%OPC SCAN
//FILECHEK EXEC PGM=IKJEFT01
//SYSTSPRT DD   SYSOUT=*
//SYSTSIN  DD  *
  ALLOCATE FI(EXISTS) +
      DSNAME('&OETEVNM',+
             ) SHR
  FREE FI(EXISTS)
/*

Note1 - you can check for multiple datasets in the same job if you want to
Note2 - The TWSz JCL VARIABLE OETEVNM is the name of the ETT triggering event and is available to ALL operations in an ETT-added application.

2. Set up the application using conditional dependencies to complete the entire occurrence automatically if the test job gets an RC12, or to proceed to process the data if the test job gets an RC00. That would look something like this:

Application:         DST#CND#DEP#DEMO    Conditional dependencies demo

 Row  Oper      Duration  Job name  Internal preds     Morepreds  No.of
 cmd  ws   no.  HH.MM.SS                               -IntExt -  Conds  
 '''' CPUA 005  00.00.01  FILETEST                       0   0      0
 '''' CPUA 010  00.00.01  JOBB                           0   0      1
 '''' CPUA 015  00.00.01  JOBC      010                  0   0      1
 '''' CPUA 020  00.00.01  JOBD      015                  0   0      1
 '''' CPUA 025  00.00.01  JOBE      020                  0   0      1
 '''' LAST 255  00.00.01  DUMMY     005 010 015 020 025  0   0      0
 **************************** Bottom of data **************************

Jobs JOBB through JOBE process the data in the incoming file, and run in sequence after the file is verified by job FILETEST. All operations in an application must be connected by "real" dependencies (conditionals don’t count), and there also must be an available path within the application to follow if the conditional dependencies do not resolve. To satisfy these requirements, we make all operations predecessors of the dummy operation on non-reporting workstation LAST.

Jobs JOBB-JOBE all have identical CONDITIONAL DEPENDENCIES as shown below:


----------------------- CONDITION DEFINITIONS -------- Row 1 to 2 of 2
Application     : DST#CND#DEP#DEMO       Conditional dependencies demo
Operation       : CPUA 010    JOBB                                             Condition       : 001                                                          
Rule            : All condition dependencies in this list must be true
Oper     Application Id   Jobname StepName ProcStep Co Co St  Ret.Code
ws.  no. (for ext Ad only)                          Ty OP Val Val1 Val2
CPUA 005                  FILETEST         FILECHEK RC NE     0012  
CPUA 005                  FILETEST                  ST EQ C          
**************************** Bottom of data ***************************

Lastly, set the HIGHRC for the FILETEST job to 0 and create a NOERROR entry to set the job to "C" status if it ends with an RC12.

When this is all in place:
1. If step FILECHEK in JOB FILETEST gets an RC00, both conditions are true, the conditional dependency is resolved, and jobs B, C, D, and E run in sequence.
2. If FILECHEK gets an RC12, it is set to "C" by NOERROR, but the RC12 is captured, making the first condition FALSE, and jobs B, C, D, and E are EXCLUDED… allowing the application to be set to COMPLETE.
3. If FILECHEK gets any RC other than 0 or 12, it is set to ERROR and both conditions remain UNDEFINED (unevaluated). This allows you to correct the problem and rerun FILETEST…. until it gets either an RC00 or an RC12.