IBM AS/400 manual Creating, Commands, Module Object, Chapter

Creating a Module Object

Chapter

7. Creating

a

Program

with

the

CRTRPGMOD

and

CRTPGM

Commands

The

two-step

process of program creation consists of compiling source

modules

using

CRTRPGMOD

and

then

binding one or more module objects into

program

using

CRTPGM.

With

this

process you can create permanent

module

This in turn allows you to modularize an application without recompiling

application.

It also allows you to reuse

the same

module

in differe

This

chapter

shows

how

to:

¹

Create

a

module

object

from

RPG

IV source

¹

Bind

modules

into

a

program

using

CRTPGM

¹

Read

a

binder

listing

¹ Change a module or program

Creating

a Module Object

A module

is

a nonrunnable object (type *MODULE) that is the output of

compiler. It is

the

basic building

block of an ILE program.

An

ILE RPG

module consists

of

one

or

more

procedures, and

the

file

and

static

storage

used

by

all

the procedures in

the module.

The

can

make

up

an

ILE

RPG

module

are:

¹an optionalmain procedure which consists of the set of H, F, D, I, specifications that begin the source. The main procedure has its

semantics and	logic	cycle; neither of which is affected by thos
RPG modules in	the	program.

¹zero or moresubprocedures , which are coded on P, D, and C specifica Subprocedures do not use the RPG cycle. A subprocedure may have

storage that is available for use only by the subprocedure itse

The main procedure (if coded) can always be called by other modul program. Subprocedures may be local to the module or exported. If they can only be called by other procedures in the module; if the from the module, they can be called by any procedure in the progr

Module creation consists of compiling a source member, and, if that i creating a *MODULE object. The *MODULE object includes a list of impo exports referenced within the module. It also includes debug data at compile time.

A module cannot be run by itself. You				must bind one or more			modules
create	a program object	(type *PGM)	which can		then be run.		You can
or more	modules together	to create	a	service	program	object	(type
then access the procedures within the				bound	modules	through	static
calls.

This ability to combine modules allows you to:

 Copyright IBM Corp. 1994, 1999 73