Parameter field

The parameter field consists of two types of parameters: positional parameters and keyword parameters. All positional parameters must precede all keyword parameters. Keyword parameters follow the positional parameters.

Commas: Use commas to separate positional parameters, keyword parameters, and subparameters in the parameter field.

Positional Parameters: A positional parameter consists of:

Characters that appear in uppercase in the syntax and must be coded as shown
Variable information, or
A combination.

For example, DATA on a DD statement, programmer's-name on a JOB statement, and PGM=program-name on an EXEC statement.

Code positional parameters first in the parameter field in the order shown in the syntax. If you omit a positional parameter and code a following positional parameter, code a comma to indicate the omitted parameter. Do not code the replacing comma if:

The omitted positional parameter is the last positional parameter.
All following positional parameters are also omitted.
Only keyword parameters follow.
All positional parameters are omitted.

Keyword parameters: A keyword consists of characters that appear in uppercase in the syntax and must be coded as shown followed by an equals sign followed by either characters that must be coded as shown or variable information. For example, RD=R and MSGCLASS=class-name on the JOB statement.

Code any of the keyword parameters for a statement in any order in the parameter field after the positional parameters. Because of this positional independence, never code a comma to indicate the absence of a keyword parameter.

Multiple subparameters: A positional parameter or the variable information in a keyword parameter sometimes consists of more than one item, called a subparameter list. A subparameter list can consist of both positional and keyword subparameters. These subparameters follow the same rules as positional and keyword parameters.

When a parameter contains more than one subparameter, separate the subparameters by commas and enclose the subparameter list in parentheses or, if indicated in the syntax, by apostrophes. If the list is a single keyword subparameter or a single positional subparameter with no omitted preceding subparameters, omit the parentheses or apostrophes.

Null positional subparameters: You are allowed to specify null (that is, omitted) positional subparameters except where the Syntax section of a particular parameter states otherwise. (For example, null positional subparameters are not allowed on a COND parameter of an EXEC statement or on an AMP parameter of a DD statement.) You specify a null positional subparameter by following the coding rules listed previously for an omitted positional parameter.