TAL Programmer's Guide

CRE Services
Introducing TAL
096254 Tandem Computers Incorporated 1–3
System Services Your program can ignore many things such as the presence of other running programs
and whether your program fits into memory. For example, programs are loaded into
memory for you and absent pages are brought from disk into memory as needed.
System Procedures The file system treats all devices as files, including disk files, disk packs, terminals,
printers, and programs running on the system. File-system procedures provide a
file-access method that lets you ignore the peculiarities of devices. Your program can
refer to a file by the file’s symbolic name without knowing the physical address or
configuration status of the file.
Your program can call system procedures that activate and terminate programs
running in any processor on the system. Your program can also call system
procedures that monitor the operation of a running program or processor. If the
monitored program stops or a processor fails, your program can determine this fact.
System procedures are described in the Guardian Procedure Calls Reference Manual and
the Guardian Programmer’s Guide for your system.
TAL Run-Time Library The TAL run-time library provides routines that:
Initialize the Common Run-Time Environment (CRE) when you use D-series
compilers (as described later in this manual)
Prepare a program for SQL statements (as described in the NonStop SQL
Programming Manual for TAL)
CRE Services The CRE provides services that support mixed-language programs compiled on
D-series compilers. A mixed-language program can consist of C, COBOL85,
FORTRAN, Pascal, and TAL routines.
A routine is a program unit that is callable from anywhere in your program. The term
routine can represent:
A C function
A COBOL85 program
A FORTRAN program or subprogram
A Pascal procedure or function
A TAL procedure or function procedure