JCL - Coding Concepts

1. Creating a data set member for JCL

2. Coding JCL (using a predefined sample)

3. Submitting the job

4. Viewing the job output

1. Installation conventions
   
   Every job must include special accounting and identifying information, which varies from one z/OS installation to another. To submit your JCL successfully, you need to find out the conventions that are followed at your company.
   
   You may need to ask a mentor or co-worker to help you identify the job card. So that we will be able to create a job statement for your JCL.
   
   
2. How to allocate and edit a data set
   
   First, you will be entering JCL statements into a data set so that you can subsequently modify and reuse them as required. Therefore, you must know how to use ISPF panels (or an equivalent technique) to allocate and edit the data set according to the specific requirements of your z/OS system.
   
   A common programming practice is to use JCL as the last qualifier in the name of any data set that is to contain JCL. for example, userid.SORT.JCL
   
   Allocate a data set to contain your JCL. Use ISPF (or equivalent function) to allocate a data set named userid.SORT.JCL (where userid is your TSO user ID) with a fixed-block format (RECFM=FB) and a logical record length of 80 (LRECL=80).
   
   
3. The job to be done and the resources needed
   
   You need to determine what work you plan to have z/OS perform:
   
   

   • What inputs (resources) you will need and where they are located

   • What program you plan to use.

   • Where the output, if any, should go. (When the job completes, you will either dispose of the output or hold it for later printing or for viewing).

   
   

   For this example, we are going to see sorting a simple file and list the contents alphabetically.

   Edit the JCL data set that you just allocated userid.SORT.JCL and add the below JCL. Use ISPF (or equivalent function) to edit the data set.

   //SORT001 JOB '417','SRINI',NOTIFY=XSR12345,MSGCLASS=S, // MSGLEVEL=(1,1),CLASS=C ---> JOB statement with parameters //* //STEP1 EXEC PGM=SORT ---> EXEC statements to execute SORT utility //SYSIN DD * ---> DD statement with DD name SYSIN, specifies how you want the sort to be done SORT FIELDS=(1,10,CH,A) /* //SYSOUT DD SYSOUT=* ---> DD statement with DD name SYSOUT, specifies the data set to which SORT will write its messages. //SORTIN DD * ---> DD statement with DD name SORTIN, specifies input records or file. JANUARY FEBRUARY MARCH APRIL MAY JUNE JULY AUGUST SEPTEMBER OCTOBER NOVEMBER DECEMBER /* //SORTOUT DD SYSOUT=* ---> DD statement with DD name SORTOUT, specifies output record will be return. /*

   Note: '--->' symbol is not part of JCL coding. we just added a description for each line for your reference. Please omit the text after the "--->"(including) in your JCL.
4. Submit the JCL to the system as a job

   When you have finished entering the JCL into the data set, submit the job by entering the SUBMIT command from the ISPF EDIT command line, the TSO/E command line, or following a READY mode message.

   When the job ends, you will receive a message indicating one of three conditions: job successful, JCL error, or program abend.
   
   If the message indicates the error or abend condition, you have to find the error reason and correct the error. then submit the job again(i.e. review steps 2 and 3 of this exercise to make sure that you followed the instructions exactly, then resubmit the job.).

   Use your installation's viewing facility (for example, SDSF) to view the output and determine whether the job completed successfully.

5. How to view and understand held output.

   Running your job will produce three types of held output:

   1. System messages from JES and z/OS 2. Your JCL code with procedures expanded, overrides applied, and symbolics resolved. 2. Output as requested by the JCL code.

   
   

   Held output may be viewed, printed, or purged. You can get below listed deails from the SDSF.

   1. Installation-specific detals and it may differ on each system. 2. Amount of execution time of the job. 3. It contains the JCL statements or JCL listing, that resulted from the job. 4. The system output messages resulting from processing the job. 5. The condition code 0000 tells you that the program ran successfully. You receive one condition code for each step in the job. If a condition code is non-zero, that means job run failed. 6. Also, you can see output produced by the program.