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

Language Elements
NCL Summary
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System variables are variables distributed with your NonStop NET/MASTER MS
software that have the reserved stem of &SYS.. System variables hold system-
maintained information. This includes:
Date and time
Cursor position
NCL information
Operating system information
Return codes for error handling
Terminal hardware information
Window information
Operating system information
All system variables are available for reading by an NCL process. An NCL process
cannot create system variables. System variables are implicitly assigned values during
NCL process execution. Some system variables can be modified using an assignment
statement.
All global variables begin with the reserved prefix of &GLBL. Global variables hold
information that is maintained by NCL processes. When a global variable is created,
the information it contains is available for use by all NCL processes that are executing
in a NonStop NET/MASTER MS system.
Hint To improve the performance of NonStop NET/MASTER MS, minimize the use of global variables.
Verbs use MDO variables for accessing mapped data. The data in these variables is
interpreted by Mapping Services using maps such as $MSG, $NCL, $SEC, and $SPI.
Any variable created by an NCL process is called a user variable. They are local to the
current procedure or function unless shared.
A user variable with a numeric name (&1, &2, and so on) is called a parameter.
Parameters are created when a parameter list is specified in a procedure or function
call. Parameters hold data shared from one procedure or function to another
procedure or function. Parameters are positional and must be entered in the order the
callee expects to receive them. A parameter count is kept in the system variable
&SYS.PARMCNT. The system variable &SYS.ALLPARMS holds all the parameters
passed in a single string.
Variables are discussed in more detail in the NonStop NET/MASTER NCL Reference
Manual.