JCL JOB statements: Positional and frequently used parameters

In addition to the two positional parameters (job accounting information and programmer name), the JOB statement also may contain over 20 keyword parameters. But you'll most often use only this handful.

Positional parameters

JOB statements have two positional parameters that apply to the entire job:

Job accounting information: The value that you code for job accounting information depends on the guidelines set at your company. The value is usually a number that identifies a department or person to whom processor time is billed.
Job accounting information may consist of multiple pieces of information, not just a single value as shown in this example.
Programmer name: The programmer name identifies the person or group responsible for a job. The programmer's name is not a mandatory part of the JOB statement unless your company has made it so.

Keyword parameters

As with the positional parameters for the JOB statement, keyword parameter values apply for the entire job. The JOB statement has over twenty different keyword parameters, but you are most likely to use only these few:

CLASS

Use the CLASS parameter if your company uses classes to group jobs. Grouping jobs helps to:

Achieve a balance between different types of jobs. A good balance of job class assignments helps to make the most efficient use possible of the system.
Avoid contention between jobs that use the same resources.

Because jobs classes are site-specific, you have to check with your operations department to determine which job classes are available for use.

TIME

Use the TIME parameter to specify the maximum amount of time that a job may use the processor or to find out through messages how much processor time a job used. Using the TIME parameter prevents an error in your program from causing it to run longer than necessary.

You can use the TIME parameter on a JOB statement to decrease the amount of processor time available to a job or job step below the default value. You cannot use the TIME parameter on a JOB statement to increase the amount of time available.

MSGLEVEL

The MSGLEVEL parameter controls how the JCL, allocation messages, and termination messages are printed in the job's output listing (SYSOUT).

The MSGLEVEL parameter value consists of two subparameters:

statement: The statement subparameter indicates which job control statements the system is to print on the job log.
messages: The messages subparameter indicates which messages the system is to print on the job log.

MSGCLASS

You can use the MSGCLASS keyword parameter to assign an output class for your output listing (SYSOUT). Output classes are defined by the installation to designate unit record devices, such as printers.

Both the MSGLEVEL and MSGCLASS parameters have default settings, depending on your company's guidelines. The operating system uses the default setting if you omit one or both of the keyword parameters from the JOB statement. In this case, you would code these parameters only if you want to have a different message level or message class than the preset values.

The MSGLEVEL subparameters have only IBM-supplied values that you may specify, but output class assignments and the default settings for both parameters depend on values your company chooses to use.