Stepping Through the Program Object

Displaying

UCS-2

Data

 

 

 

 

 

 

 

The

value

displayed

for

UCS-2

fields has

been

translated

into

readab

For

example,

if a UCS-2 field

has been

set to

%UCS2('abcde'),

then t

played for

that field would

be 'abcde'. You can display

UCS-2 data

using

the

:u

suffix

for

EVAL.

 

 

 

 

 

Displaying Variable-Length Fields

 

 

 

 

 

 

 

 

 

 

 

 

When you use EVAL fldname for

a

variable

length

field,

only the

data

field is shown. When you use

any

suffix

such

 

as

:c

or

:x

for

the

including the length is shown.

To

determine

the

current

length

of

a

va

field, use EVAL fldname:x. The

length is the first four

hexadecimal

d

format.

You must

convert this

value

to decimal

form

to

get

the length;

if the

result is

003DF1F2...,

the

length

is 003D

which

is

(3

*

16)

+

Displaying Data

Addressed

by Pointers

If

you

want

to see

what

a pointer is pointing to, you can use the

with

the

:c

or :x suffix. For example, if pointer field PTR1 is poin

character

data,

 

 

EVAL PTR1:c 10

 

 

 

will

show

the

contents

of

those 10 bytes.

You can also show the contents in hexadecimal using:

EVAL PTR1:x 10

This would be especially useful when the data that the pointer addre stored in printable form, such as packed or binary data.

Displaying Null-Capable Fields

You

can

use

the

EVAL debug command to display the null indicator

of

a

capable field. The null indicator

is

an internal

variable

(similar

to

th

for multiple-occurrence DS) which is named _QRNU_NULL_fieldname. The

 

 

fieldname can be

the

name

of

an

array

if the

array

is

null-capable.

When the debugger displays a

null-capable field, the content

of

the

 

played

regardless

 

of

whether

the

field

is

considered

null.

For

exampl

FLD1

is

null-capable,

and

is

currently

null.

Then

the result

of

EVAL

 

 

_QRNU_NULL_FLD1 is

 

'1'

 

and

EVAL

FLD1

shows

the

current content

of

FLD1,

even

though

its null

indicator

is on.

 

 

 

 

 

 

 

 

 

EVAL _QRNU_NULL_FLD1

Result:

_QRNU_NULL_FLD1 = '1'

 

 

 

 

 

 

 

 

EVAL FLD1

 

 

Result:

FLD1 = 'abcde'

 

 

 

 

 

 

 

 

 

Using

Debug Built-In Functions

 

 

 

 

The

following built-in

functions are

available

while

using the ILE source

%SUBSTR

 

 

 

 

 

 

 

Substring a

string

field.

 

 

 

%ADDR

Retrieve the address of a field.

 

 

%INDEX

Change the index of a table or multiple-occurrence data struct

%VARS

Identifies

the

specified

parameter

as

a variable.

206 ILE RPG for AS/400 Programmer's Guide

Page 229 Page 231
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IBM AS/400 manual Displaying Variable-Length Fields, By Pointers, Displaying Null-Capable Fields, Displaying Data
Page 229 Page 231

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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