pTAL Reference Manual (H06.03+)

HP pTAL Reference Manual—523746-005
10-1
10 Pointers
This section describes the syntax for declaring and initializing pointers you manage
yourself. You can declare the following kinds of pointers:
•
Simple pointer—a variable into which you store a memory address, usually of a
simple variable or array, which you can access with this simple pointer.
•
Structure pointer—a variable into which you store the memory address of a
structure which you can access with this structure pointer.
The compiler allocates 32 bits for all pointers except .SG. In expressions involving
addresses, however, the compiler treats all operands as if they were word addresses
except extended addresses the and addresses of strings. The pointer’s object data
type determines the pointer’s address type and identifies the addressing type and
location of data that your pointers will reference. For information about working with
addresses, see Section 5, Expressions.
Some portions of this section describe how you reference data in system globals.
System globals can be accessed only by programs running as privileged procedures.
Topics:
•
Overview of Pointer Declaration on page 10-2
•
Declaring VOLATILE Pointers on page 10-4
•
Address Types on page 10-5
•
Declaring Simple Pointers on page 10-12
•
Initializing Simple Pointers on page 10-14
•
Declaring Structure Pointers on page 10-16
•
Initializing Structure Pointers on page 10-17
•
Declaring System Global Pointers on page 10-20