Parameters within Syntax

• required

• optional

• positional

Required parameters

You must enter all required parameters; otherwise, MPE/iX displays an error message when you enter the command. In the syntax diagrams for each command, either braces { } or no marks surround required parameters.

In the following example, myfile is a required parameter because no marks surround it:

   BUILD myfile

Anything italicized, such as myfile, is a representational name or value and must be replaced with an actual name or value.

Sometimes you must select one parameter from two or more parameters. In the following example, you must provide either a job number or a session number because braces surround these parameters:

   ALTJOB {#Jnnn

           #Snnn}

Optional parameters

You can either specify or ignore optional parameters, if any, depending on how you want the command to execute. In the syntax diagrams for each command, brackets [ ] surround optional parameters. If you ignore optional parameters, MPE/iX uses the system-defined default values for each parameter.

In the following example, [;PASS] is an optional parameter because brackets surround it:

   NEWGROUP groupname [;PASS=[password]]

In this example, PASS is the parameter and password is the parameter value. You would substitute an actual password in place of password to provide a value for the parameter PASS. The syntax diagram indicates that the value password is optional within the optional parameter PASS.

Positional parameters

The effect of a positional parameter depends on its location in the parameter list. In the syntax diagram for each command, the comma (,) separates positional parameters. If you omit a positional parameter from the list, you must provide a comma placeholder that would normally precede that parameter.

In the following example, the parameter values that follow the command are positional:

   LIMIT 10,32

In the following example, a comma holds the position of the current value of the first parameter:

   LIMIT ,32