Dfhapxpo, Defining run-time options, Run-time options for xplink programs – IBM SC34-6814-04 User Manual

Page 707

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Chapter 25. Writing programs to customize Language
Environment run-time options for XPLink programs

Considerations common to all user-replaceable programs

Note that the comments contained in Chapter 5, “General notes about
user-replaceable programs,” on page 435
apply to this chapter.

This chapter describes how to write a user-replaceable program that will be called
by CICS during the initialization of the Language Environment enclave for a C or
C++ program compiled with the XPLINK option.

The program is :
v

“DFHAPXPO”

DFHAPXPO

This program is loaded during the PIPI preinitialization phase of each Language
Environment enclave where C or C++ programs compiled with the XPLINK option
are to be run. It allows you to alter the default Language Environment run-time
options. See the z/OS Language Environment Programming Guide for details of the
Language Environment options that can be reset. The program must be written in
Assembler language.

Defining run-time options

The options are specified as a human-readable string containing a 2-byte string
length followed by the run-time options. The maximum length allowed for all
Language Environment run-time options is 255 bytes, so you are recommended to
use the abbreviated version of each option and restrict your changes to a total of
under 200 bytes. The values you specify are not checked by CICS before being
passed to Language Environment.

A CICS-supplied DFHAPXPO module is provided, setting some run-time options.
See the fully-commented module source for an example of how to set these
options.

CICS programs can include a CEEUOPTS CSECT to supply Language
Environment run-time options to control the program's execution.

© Copyright IBM Corp. 1977, 2011

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