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

*Procedure Enabler. This procedure enables a cancel handler,

*then gets an error which causes Enabler to be canceled.

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

 

 

P Enabler

B

 

 

* Local variables

 

 

 

D Handler

S

*

PROCPTR INZ(%PADDR('CANHDLR'))

D Msg

S

20A

 

D pMsg

S

*

INZ(%ADDR(Msg))

D Zero

S

5P

0 INZ(0)

D Count

S

5I

0 INZ(0) STATIC

D Array

S

1A

DIM(2)

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

 

 

*Enable the cancel handler. When this procedure gets canceled,

*procedure 'CANHDLR' will be called.

 

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

 

 

C

 

CALLB

'CEERTX'

 

C

 

PARM

 

Handler

C

 

PARM

 

pMsg

C

 

PARM

 

*OMIT

 

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

 

 

 

* This procedure will be called three times. The first two times

 

* will get an error while the cancel handler is enabled.

 

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

 

 

C

 

EVAL

Count = Count

+ 1

C

 

SELECT

 

 

C

 

WHEN

Count = 1

 

C

 

EVAL

Msg = 'Divide

by zero'

C

 

EVAL

Zero = Zero / Zero

C

 

WHEN

Count = 2

 

C

 

EVAL

Msg = 'String

error'

C

'A'

SCAN

'ABC':Zero

Zero

 

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

 

 

*On the third call, disable the cancel handler. The array index

*error will cause the procedure to fail, but the handler wi￿ll

*not be invoked.

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

 

 

C

WHEN

Count = 3

C

CALLB

'CEEUTX'

C

PARM

Handler

C

PARM

*OMIT

C

EVAL

Msg = 'Array index error'

C

EVAL

Array(Zero) = 'x'

C

ENDSL

 

 

P Enabler

E

 

 

 

 

 

 

Figure 118 (Part

3 of 4).

Enabling and Coding a Cancel Handler for a Subprocedure

246 ILE RPG for AS/400 Programmer's Guide

Page 270
Image 270
IBM AS/400 manual INZ0 Static, Callb Ceertx Parm, Select When, Scan, Callb Ceeutx Parm, Parm Omit Eval

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.