IBM AS/400 manual Prototyped Calls, Multiple Procedures Module

Multiple Procedures Module

Subprocedures	offer	another	feature. You	can	pass parameters			to a	s
by value, and you can call			a subprocedure	in	an	expression	to	return
Figure 12 on	page 34	shows	what a module might		look	like with	multiple		p
dures.

	*MODULE
			Main Procedure
			H specifications
			F specifications
Main			D specifications - Data items visible
Source					throughout module
Section			I specifications
			C specifications
			O specifications
			Subprocedure 1
			P specification
			D specifications - Data items visible only
					to Subprocedure 1
			C specifications - Can access local and
					global data items
			P specifications
			Subprocedure 2
		P specification
		D specifications - Data items visible
				only to Subprocedure 2
		C specifications - Can access local and
				global data items
		P specifications

Program Data - part of main source section

Figure 12. An ILE RPG module with Multiple Procedures

Local Scope

Local Scope

Global Scope

As the picture suggests, you can now			code	subprocedures	to	handle	pa
tasks.	These	tasks may be needed by	the	main procedures	or by		othe
the application. Furthermore, you can declare temporary data						items	in
dures	and not	have to worry if you	have	declared them	elsewhere		in

Prototyped Calls

To call a subprocedure, you must use a prototyped call. You can also program or procedure that is written in any languageprototypedin callthis way. A is one where the call interface is checked at compile time through t

prototype.prototypeA is a definition of the call interface. It includes information:

¹ Whether the call is bound (procedure) or dynamic (program)

¹ How to find the program or procedure (the external name)

34 ILE RPG for AS/400 Programmer's Guide