Compaq NonStop™ 
              Pathway/iTS SCREEN 
              COBOL Reference 
              Manual
              Abstract
                     This manual describes the SCREEN COBOL programming language, which Compaq 
                     NonStop™ Pathway/iTS application programmers use to write programs that communicate with 
                     operator terminals or intelligent devices and send data to users.
              Product Version
                     Pathway/iTS 1.0
                   
              Part Number           Published
              426750-001            October 2000
          Document History 
           Part Number         Product Version                        Published
           127341              Pathway/TS D42                         August 1996
           136664              Pathway/TS D42+                       October 1997
           139453              Pathway/TS D42+                       January 1998
           426750-001          Pathway/iTS 1.0                       October 2000
          Ordering Information
                For manual ordering information:  domestic U.S. customers, call 1-800-243-6886; international customers, contact 
                your local sales representative.
          Document Disclaimer
                Information contained in a manual is subject to change without notice.  Please check with your authorized  
                representative to make sure you have the most recent information.
          Export Statement
                Export of the information contained in this manual may require authorization from the U.S. Department of 
                Commerce.
          Examples
                Examples and sample programs are for illustration only and may not be suited for your particular purpose. The 
                inclusion of examples and sample programs in the documentation does not warrant, guarantee, or make any 
                representations regarding the use or the results of the use of any examples or sample programs in any 
                documentation. You should verify the applicability of any example or sample program before placing the software 
                into productive use.
          U.S. Government Customers
                FOR U.S. GOVERNMENT CUSTOMERS REGARDING THIS DOCUMENTATION AND THE ASSOCIATED 
                SOFTWARE:
                These notices shall be marked on any reproduction of this data, in whole or in part.
                NOTICE:  Notwithstanding any other lease or license that may pertain to, or accompany the delivery of, this 
                computer software, the rights of the Government regarding its use, reproduction and disclosure are as set forth in 
                Section 52.227-19 of the FARS Computer Software—Restricted Rights clause.
                RESTRICTED RIGHTS NOTICE:  Use, duplication, or disclosure by the Government is subject to the 
                restrictions as set forth in subparagraph (c)(1)(ii) of the Rights in Technical Data and Computer Software clause at 
                DFARS52.227-7013.
                RESTRICTED RIGHTS LEGEND:  Use, duplication or disclosure by the Government is subject to restrictions 
                as set forth in paragraph (b)(3)(B) of the rights in Technical Data and Computer Software clause in 
                DAR7-104.9(a).  This computer software is submitted with “restricted rights.”  Use, duplication or disclosure is 
                subject to the restrictions as set forth in NASA FAR SUP 18-52 227-79 (April 1985) “Commercial Computer 
                Software—Restricted Rights (April 1985).”  If the contract contains the Clause at 18-52 227-74 “Rights in Data 
                General” then the “Alternate III” clause applies.
                U.S. Government Users Restricted Rights — Use, duplication or disclosure restricted by GSA ADP Schedule 
                Contract.
                Unpublished — All rights reserved under the Copyright Laws of the United States.
                        Compaq NonStop™ Pathway/iTS 
                        SCREEN COBOL Reference 
                        Manual
                   Index               Examples                Figures                Tables
                What’s New in This Manual    ix
                    Manual Information   ix
                    New and Changed Information     ix
                About This Manual    xi
                    Who Should Read This Manual     xi
                    Related Documentation    xi
                    Your Comments Invited    xii
                    Notation Conventions   xiii
          1. Introduction to SCREEN COBOL
                Pathway Environment Overview     1-2
                    Pathway System Components     1-2
                Communication Between Processes     1-7
                Developing Programs With System Tools     1-8
                    Generating Object Files With the Compiler  1-8
                    Managing Object Files With SCUP     1-10
                Designing Program Logic    1-11
                    Organizing SCREEN COBOL Program Groups 1-11
                    General Rules for Program Design   1-12
          2. SCREEN COBOL Source Program
                Program Operating Modes     2-1
                    Block Mode Program     2-2
                    Conversational Mode Program    2-2
                    Intelligent Mode Program   2-2
                Program Organization   2-3
                                     Compaq Computer Corporation—426750-001
                                                       i
           Contents                                         2.  SCREEN COBOL Source Program (continued)
           2. SCREEN COBOL Source Program (continued)
                Language Elements     2-3
                    SCREEN COBOL CharacterSet 2-4
                    Editing Characters   2-5
                    Punctuation Characters   2-5
                    Separators   2-6
                    SCREEN COBOL Words 2-6
                    Literals  2-7
                    Mixed Data Items    2-10
                Reference Format    2-10
                    Tandem Standard Reference Format     2-11
                    ANSI Standard Reference Format     2-11
                    Comment Lines     2-12
                    Continuation Lines   2-13
                    Compiler Command Lines      2-13
                Arithmetic Operations   2-13
                    Arithmetic Expressions   2-13
                    Arithmetic Operators   2-14
                    Evaluation of Expressions   2-15
                Conditional Expressions   2-18
                    Simple Conditions    2-18
                    Complex Conditions     2-21
                    Condition Evaluation Rules   2-23
                Tables   2-24
                Data Reference    2-25
                    Qualification  2-25
                    Subscripting   2-26
                    Using Identifiers  2-28
                    Using Condition-Names     2-28
                Data Representation   2-29
                    Standard Alignment    2-29
                    Optional Alignment    2-29
                     Compaq NonStop™ Pathway/iTS SCREEN COBOL Reference Manual—426750-001
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