IBM AS/400 manual ILE Condition Handlers, Using a Condition Handler

ILE Condition Handlers

ILE Condition Handlers

ILE condition	handlers	are	exception	handlers that	are registered	at	run
using the	Register	ILE	Condition	Handler (CEEHDLR)	bindable API.	They	are

to handle, percolate or promote exceptions. The exceptions are present condition handlers in the form of an ILE condition. You can register mo ILE condition handler. ILE condition handlers may be unregistered by c

Unregister		ILE Condition Handler	(CEEHDLU) bindable		API.
There	are	several reasons why	you	might want to use		an ILE condition
¹ You	can bypass language-specific			handling by	handling the exception
own	handler.

This enables you to provide the same exception handling mechanism in application with modules in different ILE HLLs.

¹ You can use this API to scope exception handling to a call stack e

The ILE bindable API CEEHDLR is scoped to the invocation that contain remains in effect until you unregister it, or until the procedure r

Note: Any	call	to	the CEEHDLR API from any	detail, total or subroutine
lation will make the condition handler active for the					entire	pr
including		all	input, calculation, and output operations.		However,	i
not	affect		subprocedures, nor will	a subprocedure	calling CEEHDLR

	affect the main procedure.
If	a subprocedure is called	recursively, only the invocation that
is	affected by it. If you want		the condition handler active for
then	CEEHDLR must be called by	each	invocation.

For information on how to use ILE condition handlers,ILE Conceptsrefer. to

Using a Condition Handler

The following example shows you how to:

1. Code a condition handler to handle the RPG 'out-of-bounds' error

2.Register a condition handler

3.Deregister a condition handler

4.Code a *PSSR error subroutine.

The example consists of two procedures:

¹RPGHDLR, which consists of a user-written condition handler for out-of substring errors

¹SHOWERR, which tests the RPGHDLR procedure.

While SHOWERR is designed primarily to show how RPGHDLR works, the two

procedures

combined are

also

useful for determining 'how' ILE exception

works. Both procedures write to QSYSPRT the 'actions' which occur as th

processed.

You

might

want

to

modify these

procedures

in

order to

si

aspects

of

ILE

exception

handling

which

you

would

like

to

explore.

Figure 116

on page 239

shows

the

source

for

the

procedure RPGHDLR.

Th

cedure

defines

three procedure

parameters: an

ILE

condition token

st

238 ILE RPG for AS/400 Programmer's Guide