Before you begin

Before creating any job, you need to know the following:

Installation conventions. Every job must include special accounting and identifying information. However, the way this information is specified varies from one MVS™ installation to another.
In order to submit your JCL successfully, you need to find out the conventions that are followed at your installation.

A worksheet has been provided at the end of this topic (see Installation conventions worksheet) as a guide for documenting this information. You may need to ask someone more familiar with your installation to help you identify the conventions indicated in the worksheet.
How to allocate and edit a data set. During the exercise, you will be entering JCL statements into a data set so that you can subsequently modify and re-use 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 MVS system. See Using ISPF to allocate and edit a data set for more information.
Note:
1. It is a common programming practice to give any data set containing JCL a name that ends in JCL, such as userid.SORT.JCL.
2. A data set that contains JCL must have a fixed-block format (RECFM=FB) with a logical record length of 80 (LRECL=80).
The job to be done and the resources needed. You need to determine what work you plan to have MVS 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.)
The job for this exercise is to sort a simple file and list the contents alphabetically. Decisions about inputs, outputs, and processing have already been made for you so that when you reach Step 2. edit the JCL data set and add the necessary JCL, all you will have to do is to copy the example code provided.
How to view and understand held output. Running your job will produce three types of held output:
- System messages (JES and MVS)
- Your JCL code with procedures expanded, overrides applied, and symbolics resolved.
- Output as requested by the JCL code
Held output may be viewed, printed, or purged. Using SDSF to view output from a job explains how to use SDSF to view JCL output.

In the example, Step 4. view and understand the output from the job and Step 6. view and understand your final output show you how the output from the exercise should look and explain what each part of the output means.