IBM TSO/E REXX User Manual

Updating Multiple Specific Lines in a Data Set
"ALLOC DA('dept5.employee.list') F(updatedd) OLD"
"EXECIO 1 DISKRU updatedd 2 (LIFO"
PULL line
PUSH 'Crandall, Amy AMY 5500'
"EXECIO 1 DISKW updatedd"
"EXECIO 1 DISKRU updatedd 5 (LIFO"
PULL line
PUSH 'Leone, Mary MARYL 5530'
"EXECIO 1 DISKW updatedd (FINIS"
"FREE F(updatedd)"
When you issue multiple EXECIO commands to the same data set before closing it
and do not specify a line number, the most current EXECIO command begins
reading where the previous one left off. Thus to scan a data set one line at a time
and allow a user at a terminal to update each line, you might write the following
exec.
Example of Scanning Each Line for Update
/***************************** REXX ********************************/
/* This exec scans a data set whose name and size are specified by */
/* a user. The user is given the option of changing each line as */
/* it appears. If there is no change to the line, the user presses*/
/* Enter key to indicate that there is no change. If there is a */
/* change to the line, the user types the entire line with the */
/* change and the new line is returned to the data set. */
/*******************************************************************/
PARSE ARG name numlines /* Get data set name and size from user */
"ALLOC DA("name") F(updatedd) OLD"
eof = 'NO' /* Initialize end-of-file flag */
DOi=1tonumlines WHILE eof = 'NO'
"EXECIO 1 DISKRU updatedd" /* Queue the next line on the stack */
IF RC = 2 THEN /* Return code indicates end-of-file */
eof = 'YES'
ELSE
DO
PARSE PULL line
SAY 'Please make changes to the following line.'
SAY 'If you have no changes, press ENTER.'
SAY line
PARSE PULL newline
IF newline = '' THEN NOP
ELSE
DO
PUSH newline
"EXECIO 1 DISKW updatedd"
END
END
END
Additional Examples
Using EXECIO to Process Information ...
Chapter 12. Processing Data and Input/Output Processing 163

IBM TSO/E REXX Specifications

General

Brand	IBM
Model	TSO/E REXX
Category	Computer Hardware
Language	English

Summary

Part 1. Learning the REXX Language

Chapter 1. Introduction

Explains the REXX programming language, its features, and suitability for various users.

Chapter 2. Writing and Running a REXX Exec

Details the process of writing, running, and understanding REXX execs, including syntax rules and common issues.

Chapter 3. Using Variables and Expressions

Covers REXX variables, expressions, operators, and tracing techniques for data manipulation and calculations.

Chapter 4. Controlling the Flow Within an Exec

Explains how to alter REXX exec execution using conditional, looping, and interrupt instructions.

Chapter 5. Using Functions

Describes REXX functions, including built-in, user-written, and packages, and how to use them.

Chapter 6. Writing Subroutines and Functions

Guides on writing, calling, and passing information to REXX subroutines and functions.

Chapter 7. Manipulating Data

Covers REXX data manipulation using compound variables, stems, and various parsing techniques.

Part 2. Using REXX

Chapter 8. Entering Commands from an Exec

Explains how REXX execs can interact with the operating system by issuing TSO/E and host commands.

Chapter 9. Diagnosing Problems Within an Exec

Details techniques for diagnosing and debugging REXX execs using tracing and special variables.

Chapter 10. Using TSO/E External Functions

Describes TSO/E external functions available for interacting with the system and performing specific tasks.

Chapter 11. Storing Information in the Data Stack

Explains how to use the REXX data stack for temporary storage, passing information, and managing buffers.

Chapter 12. Processing Data and Input/Output Processing

Covers dynamic REXX expression modification and processing data to/from data sets using EXECIO.

Chapter 13. Using REXX in TSO/E and Other MVS Address Spaces

Explains how to run REXX execs in TSO/E and non-TSO/E MVS address spaces and available services.

Part 3. Appendixes

Appendix A. Allocating Data Sets

Guides on creating and allocating data sets, including checklists for ISPF/PDF and ALLOCATE commands.

Appendix B. Specifying Alternate Libraries with the ALTLIB Command

Details using the ALTLIB command to specify and manage alternative libraries for implicit execution.

Appendix C. Comparisons Between CLIST and REXX

Compares REXX and CLIST languages, highlighting similarities and differences in features and capabilities.

Appendix D. Notices

Provides legal notices, warranty disclaimers, copyright, and trademark information.

Bibliography

TSO/E Publications

Lists IBM publications related to TSO/E, including administration, CLISTs, and general information.

Related Publications

Lists IBM publications related to z/OS MVS and ISPF, covering system programming and administration.

Index