Rule Writing Guidelines › Operand Masking Techniques › Rules for Operands that Have Numeric Values

Rules for Operands that Have Numeric Values

Syntax Model Command Language (SMCL) is a facility that describes the syntax for a CP command. This section explains the syntax of the language so you can read a model to write command limiting rules. They also provide a more indepth knowledge of the language so you can modify the supplied models when you change the syntax of a command or need to create models and limit commands that you added to CP.

Some commands accept numeric values for operands. They also have special transposition routines that check to make sure that the numeric operand supplied is valid. Operands that fall into this category and their corresponding transposition routines are:

You can mask these operands.

Following is a brief explanation for using masking as a value for operands that accept a numeric value.

• A single * means the operand is optional
• ** used for a decimal number means 0-99
• *** used for a decimal number means 0-999
• 0* used for a decimal number means 0-09

Let’s use the SLEEP command as an example. To let someone sleep for 0 to 9 seconds, code the rule as 0* SEC UID(*) ALLOW. Had you just put a single *, CA ACF2 for z/ VM would interpret this as meaning any value can be present. Specify 0*, CA ACF2 for z/ VM to allow 0-09 seconds.

As another example, to let anyone in your site define 0-50 cylinders of TDISK, code the DEFINE rule as shown in the next example.

$KEY(DEFINE)
 T**** AS *- CYL 0* UID(*) ALLOW
 T**** AS *- CYL 1* UID(*) ALLOW
 T**** AS *- CYL 2* UID(*) ALLOW
 T**** AS *- CYL 3* UID(*) ALLOW
 T**** AS *- CYL 4* UID(*) ALLOW
 T**** AS *- CYL 50 UID(*) ALLOW
 T**** AS - - - UID(*) PREVENT
 - UID(*) ALLOW

Because you specified no MDLTYPE for this DEFINE rule, CA ACF2 for z/ VM uses the default MDLTYPE command model (as defined in the CMDLIM VMO record) for syntax checking. This rule specifies 0-50 cylinders of TDISK and any other DEFINEs.