NET/MASTER Network Control Language (NCL) Programmer's Guide

Language Elements
NCL Summary
106160 Tandem Computers Incorporated 2–19
Note The setting of the PARAM SWGUID command does not affect whether a user can switch from the current
GUID to a new GUID within NonStop NET/MASTER MS. The setting determines whether switching
occurs when a user interacts with a file or process external to NonStop NET/MASTER MS.
Variables Variables hold values that can change during the execution of an NCL process.
You do not have to explicitly declare the variables you want to use in an NCL
procedure or function. Variables are automatically created and deleted during NCL
process execution as required.
You can explicitly assign a value to a variable using the assignment statement, and you
can use the ASSIGN verb to manipulate variables in various ways. You can use the
DROP verb to delete (drop) one or more variables.
There are two types of values that a variable can hold: string and numeric. A variable
can hold one or both types of values at the same time. Values are automatically
converted from one type to another during NCL process execution according to the
current context.
You can give variables from one procedure or function, the caller, to another
procedure or function, the callee, to work with. This is called sharing variables. The
callee can change or delete the values of the variables. It can give variables back, with
any changes, to the caller.
Syntactically, there are five types of variable names:
Simple
Complex
Stem
Compound
Nested
Hint To improve the performance of an NCL process, use short variable names, containing small amounts of
data. For best results, ensure that the combined name length and contents are less than or equal to 32
bytes; for good results, ensure that either the name length or contents is less than or equal to 32 bytes.
From a functional point of view, there are five types of variables:
System
Global
Mapped data object (MDO)
User
Parameter