TNS/E Native Application Conversion Guide

TNS/E Native Application Conversion Guide—529659-003

7-1

Converting Data Definition

Language (DDL)

This section describes how to convert Data Definition Language (DDL) host language

source files that:

•

Are shared between TNS and TNS/E native programs written in C, C++, TAL, or

pTAL

and

•

Were generated by a pre-D40 product version of the DDL compiler

If these criteria apply to your DDL host language source files, follow the instructions in

this section to generate new host language source files and recompile your programs

with the new files. If your DDL host language source files are not shared between TNS

and native programs or were generated by a D4x, G-series, or H-series DDL compiler,

or your applications are written in COBOL, no actions are required.

This section discusses:

•

Background Information

•

Generating New Host-Language Source Code Files

•

Compiling With New Host-Language Source Code Files

Background Information

DDL defines data objects and translates object definitions into source code for

programming languages and other products. Data objects can include parameters,

structures, messages, database entries, and disk records. Data objects in host-

language source code generated by DDL have the same physical layout, regardless of

host language.

The native compilers align data for optimal performance on NonStop systems by

default. This default alignment is the same on TNS/R and TNS/E systems. Except for

the TNS COBOL and TNS/E native COBOL compilers, this default alignment is

different from and incompatible with the default data alignment generated by the TNS

compilers.

The TNS COBOL and TNS/E native COBOL compilers generate code with the same

data alignment. You need not change any data alignment directives before converting

a TNS COBOL program to native COBOL. You need not regenerate DDL source files

that are shared only by TNS COBOL and native COBOL programs.

Because of the data alignment incompatibility for languages other than COBOL, the

D4x, G-series, and H-series DDL compilers have been enhanced to generate host-

language source code that produces the same data alignment, whether the TNS