Micro Focus Server Express™

Programmer's Guide to Writing Programs

MERANT®

Issue 1a
January 2000

MERANT has made every effort to ensure that this manual is correct and accurate, but reserves the right to make changes without notice at its sole discretion at any time.

The software described in this document is supplied under a license and may be used or copied only in accordance with the terms of such license, and in particular any warranty of fitness of MERANT products for any particular purpose is expressly excluded and in no event will MERANT be liable for any consequential loss.

Micro Focus® and Animator® are registered trademarks, and Fileshare™, MERANT™, Micro Focus COBOL™, Micro Focus COBOL/2™, Object COBOL™, and Server Express™ are trademarks of MERANT International Limited

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Open Software Foundation™ is a trademark of Open Software Foundation

RM/COBOL® and Ryan-McFarland® are registered trademarks of Ryan-McFarland Corporation

SCO™ is a trademark of The Santa Cruz Operation, Inc

UNIX® and X/Open® are registered trademarks of X/Open Company Limited

Copyright© 2000 MERANT International Limited
All Rights Reserved

Preface

The Programmer's Guides are complete guides to specific areas of the Micro Focus COBOL systems.

This guide contains general information about writing programs, not specifically covered by any of the other books, that will help you write better applications. This includes information about making your applications portable, and interfacing with other languages.

Audience

You should be familiar with the COBOL language and with your operating system. You should read the Getting Started book for this COBOL system and be familiar with the COBOL development cycle described in the Server Express User Guide before reading other books in the book set.

MERANT

MERANT was formed by combining Micro Focus and INTERSOLV. All reference to the companies Micro Focus or INTERSOLV in this book should now be taken to mean MERANT. Micro Focus is retained as the family name for the Micro Focus product set produced by MERANT.

Notation

The notation used in the books is as follows:

• Enter refers to the carriage-return or Enter key. Where commands to be typed are shown, the Enter key is not shown. It is treated as implicit that the Enter key must be pressed at the end of the line.
  
  
• Hexadecimal numbers are enclosed in quotation marks and preceded by a lower-case "x" or "h"; for example, x"9D", h"03FF". The "x" is used when the hexadecimal number represents a character string; the "h" when it represents a numerical value.
  
  
• With COMP-X and COMP-5, PIC X is used rather than PIC 99. Unlike PIC 99, PIC X shows the length of the data item directly and so demonstrates more clearly the use of COMP-X, which is to define a binary item of the specified number of bytes.

Command Lines

The notation used to describe the format of command lines is as follows:

• Words printed in italics are generic terms representing names to be devised by you.
  
  
• Words printed in non-italic characters are the actual words you must enter. You must type them in upper or lower case as shown.
  
  
• Square brackets [ ] mean the material inside them is optional.
  
  
• Braces { } mean you must choose from the options inside them. If there is only one option in the braces, they mean repetition.
  
  
• An ellipsis (...) following { } or [ ] means you can repeat the material inside them. The number of repetitions allowed is unlimited unless otherwise stated. Square brackets [ ] with an ellipsis mean you can omit the material altogether.
  
  
• If a command line does not fit across the page, it is continued on the next line; the continuation line is indented.
  
  
• The books might refer you to the Release Notes for details specific to a particular UNIX platform.
  
  
• All command line formats and examples are for the standard UNIX shell, the Bourne shell. If you are using another shell, see your UNIX documentation for the appropriate formats.
  
  
• Where examples showing environment variables do not specifically show them being exported to the shell, it is treated as implicit that they are exported.
  
  
• Some keystrokes using function keys or the Alt or Ctrl keys are not available on all UNIX platforms. The Server Express User Guide contains a UNIX Key Usage Chart, listing how the keystrokes shown in the books map onto actual keystrokes.

Notes

• F1=Help appears on every menu in character-mode Micro Focus software. It invokes a help screen describing the current menu. F1=Help is not described in the documentation.
  
  
• What appears on your screen may differ in minor ways (for example, version numbers) from that illustrated in the books. This will not affect the operation of your software.

About this Book

This book is divided into several parts, as follows:

• Part 1 covers general aspects of writing programs, including making your programs efficient, handling large programs, using subprograms, and using some of the more advanced features of Server Express.
  
  
• Part 2 explains how to write programs so they can be moved between different environments with minimal changes. This includes natural language environments as well as computer environments.
  
  
• Part 3 explains the concepts of interfacing from and to COBOL programs, and explains how to mix COBOL programs with programs in other languages.

• Part 4 contains information about a number of general features and facilities that may help you when writing applications. These include a mechanism for enabling your users to configure your applications, and a mechanism for integrating a preprocessor to the Compiler.