CRE Programmer's Guide

Common Run-Time Environment (CRE) Programmer’s Guide—528146-004
1-1
1 Introducing the CRE
This section describes the differences between using the Common Run-Time
Environment (CRE) in the Guardian and the HP NonStop Open System Services
(OSS) environments, and in the TNS, TNS/R, and TNS/E native environments. This
section contains the following topics:
•
Mixed-Language Programming Without the CRE on page 1-1
•
What Is the CRE? on page 1-2
•
Selecting a Run-Time Environment on page 1-5
•
Advantages of Using the CRE on page 1-8
Mixed-Language Programming Without the
CRE
By default, the standards-based TNS programming languages each have their own
run-time environments defined by their respective run-time libraries (see Figure 1-1).
Each run-time library includes the math, string, heap management, trap and exception
handling, and I/O management functions that define each language-specific run-time
environment. The run-time libraries call system routines to obtain run-time services.
The language-specific run-time environments are different from one another and often
incompatible. Mixed-language programs running in these environments are limited in
their ability to use all of the features of each language and to share data between
routines written in different languages. This incompatibility severely limits the potential
for creating useful mixed-language programs.
Figure 1-1. Language-Specific Run-Time Environments
101VST .VSD
C
Program
C
RTL
COBOL
Program
FORTRAN
Program
TAL
Program
COBOL
RTL
FORTRAN
RTL
NonStop Operating System