Passing Prototyped Parameters

Passing *OMIT

You can pass *OMIT for a prototyped parameter if the called procedu that *OMIT might be passed. In other words, you can pass *OMIT if t OPTIONS(*OMIT) is specified on the corresponding parameter definition in totype. When *OMIT is specified, the compiler will generate the neces

indicate

to

the

called

procedure that the parameter has been omitte

Note:

 

*OMIT

can

only

be

 

specified

for

parameters

passed

by

reference

To

determine

if

*OMIT

has been

passed

 

to

an

ILE

RPG procedure,

use

%ADDR built-in function to

check the address of the parameter in quest

address is *NULL, then *OMIT has

 

been

passed.

You can also use the

 

(Check for Omitted Argument) bindable API. (See

Figure 65

on

page 138

fo

brief

example.)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The following is a simple

example of how *OMIT can be used. In this

 

procedure

calls

 

the

ILE

bindable

API

CEEDOD

in

order

to

decompose

an

 

tional descriptor. The CEEDOD API

expects

to

receive

seven

parameters;

six

have

been

defined

in the calling procedure. The last

parameter

o

(and

of

most

bindable

APIs)

is

the

feedback

code

which

can

be

used

how the API ended. However,

the

calling

procedure

has

been

designed

any

error

messages

via

an exception rather than this feedback code.

quently, on the

 

call

to

CEEDOD, the procedure must indicate

that the

p

the

feedback

code

has

been omitted.

 

 

 

 

 

 

 

 

 

 

 

See “Sample Service Program” on page 94 for an example of using *OMIT.

Leaving Out Parameters

The other way to omit a parameter is to simply leave it out on the be expected by the called procedure, which means that it must be prototype. To indicate that a prototyped parameter does not have to a call, specify the keyword OPTIONS(*NOPASS) on the corresponding parameter definition. Note that all parameters following the first *NOPASS one must a

specified with OPTIONS(*NOPASS).

 

 

 

You

can

specify

both *NOPASS and *OMIT

for the same

parameter, in eithe

that

is,

OPTIONS(*NOPASS:*OMIT) or

OPTIONS(*OMIT:*NOPASS).

 

As

an

example of

OPTIONS(*NOPASS),

consider

the system

API QCMDEXC

(Execute Command) which has an optional third parameter. To allow for th parameter, the prototype for QCMDEXC could be written as shown in Figure

*-------------------------------------------------------------

*This prototype for QCMDEXC defines three parameters:

*1- a character field that may be shorter in length

*than expected

*2- any numeric field

*3- an optional character field

 

*-------------------------------------------------------------

 

 

D qcmdexc

PR

 

EXTPGM('QCMDEXC')

D

cmd

 

3000A

OPTIONS(*VARSIZE) CONST

D

cmdlen

 

15P

5 CONST

D

 

 

3A

CONST OPTIONS(*NOPASS)

 

 

Figure

67. Prototype for System API QCMDEXC with Optional Parameter

140 ILE RPG for AS/400 Programmer's Guide

Page 163 Page 165
Page 164
Image 164
IBM AS/400 manual Passing *OMIT, Leaving Out Parameters, Options*Omit*Nopass, API Qcmdexc
Page 163 Page 165

AS/400 specifications

The IBM AS/400, now known as the IBM iSeries, is a midrange computer system that has been a cornerstone of enterprise computing since its introduction in 1988. Designed to provide a robust platform for business applications, the AS/400 is celebrated for its reliability, scalability, and integrated database capabilities.

One of the key features of the AS/400 is its Integrated Operating Environment, which blends hardware and software resources seamlessly. This integration allows businesses to execute diverse workloads, ranging from traditional applications to modern web-based services, all on a single platform. The operating system, OS/400 (now IBM i), offers a rich set of APIs and tools for developers, simplifying application development and management.

Another standout characteristic of the AS/400 is its built-in database, DB2 for i. This powerful relational database management system allows for efficient data handling and provides advanced features such as support for SQL, XML, and JSON, making it easier for businesses to manage their data and integrate it with other systems. The database's tight integration with the operating system enables high performance and security.

In terms of scalability, the AS/400 can accommodate small businesses as well as large enterprises, with the ability to support hundreds of users simultaneously. Its architecture allows for easy upgrades in hardware, meaning that organizations can scale their systems without replacing the entire infrastructure.

Security is another critical attribute of the AS/400. With a sophisticated security model, it offers built-in user authentication, access control, encryption, and auditing capabilities to protect data and applications from unauthorized access.

The AS/400 also supports multiple programming languages, including RPG, COBOL, Java, and PHP, giving organizations the flexibility to choose the development tools that best fit their needs. This diversity helps maintain legacy applications while also developing new ones that leverage modern technologies.

Moreover, the platform supports both traditional green-screen interfaces and modern graphical user interfaces, allowing organizations to transition smoothly into contemporary user experience paradigms.

Overall, the IBM AS/400 stands out as a resilient, flexible, and secure computing platform that enables organizations to effectively manage their business operations, streamline processes, and adapt to changing market demands. Its unique combination of integrated features and capabilities ensures that it remains relevant in today's fast-paced technology landscape.
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