Down to Earth REXX [Paperback]

Down To Earth REXX is a fitting title for the book, in that it uses a wide array of practical, real-world programming examples in teaching REXX to all levels of programmers, from introductory concepts regarding REXX syntax, File Processing and Functions to more advanced RexxUtil Functions for MS DOS under Windows and OS/2 Workplace Shell and EPM Programming techniques.

Among some of the text-based programs presented in the book that I found useful as Windows-based MS DOS environment applications are an Interactive REXX Interpreter, a Calendar Month Display program, a File Deletion with Verification utility, a Binary File Hex Display utility, a Filespec Directory Search utility and a Multiple File Text String Search utility.

There are topics which cover ANSI.SYS programming for text-based color display programming, conversion of .BAT files into REXX programs, Compound variables for use in array processing, algorithms such as Zeller's Congruence (useful in date field processing) and the use of recursion for sorting, and .INI file processing techniques.

For the majority of the program examples (primarily Text Console-based) presented in the first 17 Chapters, the programs can be easily modified to run on different platforms (in my case I used IBM Object REXX for MS-DOS under Windows95 and Red Hat Linux 6.1 running a Gnome workstation terminal).

Some of the programs are strictly OS/2 material, particularly those examples presented in Chapters 18 through 21, which cover OS/2 Applications, Workplace Shells and Interprocess Communications.

Perfect Niche has done a good job to improve the presentation of the material from the earlier SAMs edition. I found the new format easier to read and quicker to reference versus the older book. The Appendices in the Perfect Niche publication are a significant improvement over the SAMs text. Appendix D is a concise, specific reference of REXX Keywords and Functions, which I found reflecting most of the functions available in the IBM Object REXX Interpreter.

The program code is for the most part free from error. I did find an error in the Intermediate Skills Review 2 "Checker Game" program (CHEXX.CMD), in which the REXX Logical Not Operator was substituted with an erroneous "TM" superscript. For most dialogs of REXX and most PC keyboards, the "\" character can be used as a Logical Not Operator.

I would recommend this book to anyone looking for a comprehensive book rich in useful programming examples as a means to learning REXX. The cost of the publication is very favorable compared to other publications readily available. The fact that the latter portions of the book focus on OS/2 should not deter any programmers who are looking for a text for learning the REXX language as a text-based scripting language for multiple platforms.