IBM SC33-1683-02 - Manual (Page 5)

Contents
Notices . . . . . . . . . . . . . . . . . . . . . . . . . . . xvii
Programming interface information . . . . . . . . . . . . . . . . . xviii
Trademarks . . . . . . . . . . . . . . . . . . . . . . . . . . xix
Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . xxi
What this book is about . . . . . . . . . . . . . . . . . . . . . xxi
Who this book is for. . . . . . . . . . . . . . . . . . . . . . . xxi
What you need to know to understand this book . . . . . . . . . . . . xxi
How to use this book . . . . . . . . . . . . . . . . . . . . . . xxi
Notes on terminology . . . . . . . . . . . . . . . . . . . . . . xxi
Syntax notation and conventions used in this book . . . . . . . . . . . xxii
Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . xxiii
CICS Transaction Server for OS/390
. . . . . . . . . . . . . . . . xxiii
CICS books for CICS Transaction Server for OS/390 . . . . . . . . . xxiii
CICSPlex SM books for CICS Transaction Server for OS/390 . . . . . . xxiv
Other CICS books . . . . . . . . . . . . . . . . . . . . . . xxiv
Books from related libraries . . . . . . . . . . . . . . . . . . . . xxiv
ACF/TCAM books . . . . . . . . . . . . . . . . . . . . . . xxiv
MVS books . . . . . . . . . . . . . . . . . . . . . . . . . xxv
VTAM books . . . . . . . . . . . . . . . . . . . . . . . . xxv
Other related books . . . . . . . . . . . . . . . . . . . . . . xxv
Determining if a publication is current . . . . . . . . . . . . . . . . xxvi
Summary of changes. . . . . . . . . . . . . . . . . . . . . . xxvii
Changes for this edition . . . . . . . . . . . . . . . . . . . . . xxvii
Changes for CICS Transaction Server for OS/390 Release 2
. . . . . . . xxvii
Changes for CICS Transaction Server for OS/390 Release 1 . . . . . . .xxviii
Part 1. Customizing with user exit programs . . . . . . . . . . . . . . . . . 1
Chapter 1. Global user exit programs . . . . . . . . . . . . . . . 3
Overview — what is a global user exit? . . . . . . . . . . . . . . . 3
Global user exit programs . . . . . . . . . . . . . . . . . . . . 4
Register conventions . . . . . . . . . . . . . . . . . . . . . 4
31-bit addressing implications . . . . . . . . . . . . . . . . . . 5
Using CICS services . . . . . . . . . . . . . . . . . . . . . 5
Using EDF with global user exits . . . . . . . . . . . . . . . . . 6
The global work area . . . . . . . . . . . . . . . . . . . . . 6
Making trace entries . . . . . . . . . . . . . . . . . . . . . 7
Parameters passed to the global user exit program . . . . . . . . . . 7
Returning values to CICS . . . . . . . . . . . . . . . . . . . 10
Restrictions on the use of fields as programming interfaces . . . . . . . 11
Exit programs and the CICS storage protection facility . . . . . . . . . 11
Errors in user exit programs. . . . . . . . . . . . . . . . . . . 12
Defining, enabling, and disabling an exit program . . . . . . . . . . . 13
Invoking more than one exit program at a single exit . . . . . . . . . 13
Invoking a single exit program at more than one exit . . . . . . . . . 14
Sample global user exit programs . . . . . . . . . . . . . . . . 14
List of global user exit points . . . . . . . . . . . . . . . . . . . 19
Activity keypoint program exit XAKUSER . . . . . . . . . . . . . . . 25
Exit XAKUSER . . . . . . . . . . . . . . . . . . . . . . . 25
Basic Mapping Support exits XBMIN and XBMOUT . . . . . . . . . . . 27
© Copyright IBM Corp. 1977, 1999 iii