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.PL ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 INTRODUCTION This manual is a guide on how to properly write Cobol programs on the IBM-PC using Ansi-Standard COBOL Version 6.50. It is a guide on structured coding style and good programming techniques, as well as a COBOL manual. It will explain in detail the features used and the examples, but will limit the discussion to the most commonly used features of COBOL. Our goal as programmers is to write reasonably efficient programs that are easy for other programmers to read, this is necessary for maintaining the program. Whenever possible, I have tried to present a style that is useful and has been tested on other computer systems, especially the large IBM mainframe used in business. I acknowledged the possibility that the reader may one day use what he learns from this manual to write programs for such mainframes, or may port software, that is already written on these machines to the PC using COBOL 6.50. LIMITIATIONS You should note that : 1) COBOL Version 6.50 does not have the sort/merge feature. This is being added and may be out by the time you receive this manual. Please note the readme file on the floppy. NOTE:SORT MERGE HAS BEEN ADDED TO THE LIBARY. 2) It does not have the report writer feature and never will. 3) It does not have the communications feature such as CICS. I will probably add this into it, but at this time I do not have any plans to. 4) Certain features are implimented at it's first or lowest level. 5) It does have extensive screen formatting features that are not available in Cobol for the mainframe. The manual is divided into 2 parts. Chapters ? - chapters ? will familiarize the reader with the most important components of Ansi-Standard COBOL Version 6.50 and will allow him or her to start writing programs. Chapters ? - chapters ? are very important once he or she starts writing actual and especially more complex programs. The last chapter is very important in that it illustrates how to use the COBOL COMPILIER to write programs and how to write applications. INTRODUCTION PAGE 1 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 TABLE OF CONTENTS Cobol Version 6.50 users Manual Introduction LIMITIATIONS CHAPTER 1 Hardware and Software 1 Computer Systems 1 Types of Computer Systems 1 Hardware 2 Software 2 System Software 2 Programs 2 Pseudo Code 3 Figure 1.1 3 Applications 3 Developing Applications 3 CHAPTER 3 ANSI-COBOL Version 6.50 4 Introduction 4 General Characteristics 4 X3.23-1974 4 Components of COBOL 5 Statements 5 example 3.1 5 Sentence 6 example 3.2 6 Clause 6 example 3.3 6 Paragraph 7 example 3.4 7 Section 7 example 3.5 8 STATEMENT FORMAT 8 example 3.6 9 Cobol Character Set 10 Rules For Punctuation 10 Characters used in Conditions 10 Characters used in Arithmetic 11 Characters used for print editing 11 Types of Words 12 Reserved Words 12 Reserved Words List Reserved words ACCEPT - RERUN 13 Reserved Words List Reserved words list RESERVE - ZEROS 14 Non-reserved words rules 15 Data Format 15 Elementary Data Items 15 Group Data Items 16 Records 16 Files 16 COBOL Coding Form 17 CHAPTER 4 Basic COBOL Statements INTRODUCTION 18 The ACCEPT statment (format 2) TABLE OF CONTENTS PAGE 1 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 Fig.4.1 The (PRINTER) DISPLAY STATEMENT example 4.2 20 example 4.3 21 THE MOVE STATEMENT 21 EXAMPLE 4.4 21 EXAMPLE 4.5 THE ADD STATEMENT 23 EXAMPLE 4.6 23 EXAMPLE 4.7 24 THE SUBTRACT STATEMENT 24 EXAMPLE 4.8 24 EXAMPLE 4.9 25 THE MULTIPLY STATEMENT 25 EXAMPLE 4.10 25 EXAMPLE 4.11 THE DIVIDE STATEMENT 27 EXAMPLE 4.12 27 EXAMPLE 4.13 28 THE GIVING CLAUSE 28 EXAMPLE 4.14 28 EXAMPLE 4.15 29 THE ROUNDED CLAUSE 29 EXAMPLE 4.16 30 EXAMPLE 4.17 31 THE PERFORM STATEMENT 31 EXAMPLE 4.20 31 THE ON SIZE ERROR CLAUSE 32 EXAMPLE 4.22 32 THE GO TO STATEMENT 33 EXAMPLE 4.24 34 THE COMPUTE STATEMENT 35 EXAMPLE 4.26 35 CHAPTER 5 BASIC FILE OPERATIONS INTRODUCTION 37 FILES 38 FILE ORGANIZATION 38 RECORDS 38 OPEN STATEMENT 39 OPEN RULES 39 THE CLOSE STATEMENT 39 THE READ STATEMENT 40 THE WRITE STATEMENT (PRINT FILE) 40 EXAMPLE 5.01 41 CHAPTER 6 CODING THE IDENTIFICATION AND ENVIRONMENT DIVISIONS INTRODUCTION 43 THE IDENTIFICATION DIVISION 44 THE ENVIRONMENT DIVISION. 44 THE CONFIGURATION SECTION 44 THE INPUT-OUTPUT SECTION 45 RULES FOR CODING THE INPUT-OUTPUT SECTION 45 CHAPTER 7 TABLE OF CONTENTS PAGE 2 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 CODING THE DATA DIVISION Introduction 46 Sections 47 File Section 47 FILE SECTION RULES 47 File Record Entries 47 Data Item Definition 48 Rules for coding Data items 48 WORKING-STORAGE SECTION 49 LINKAGE SECTION 49 SCREEN SECTION 49 CHAPTER 8 CODING THE PROCEDURE DIVISION INTRODUCTION 50 Structured programming 51 Program Constructs 51 The IF condition 51 Modular Programming 52 The Main Line Section 52 Other sections 52 Paragraphs 53 Procedure Names 53 Statements and Sentences 54 CHAPTER 9 Screen Processing Accept 3 format Introduction 55 Screen Format 56 Screen Header 56 Data Area 56 THE SCREEN SECTION 57 RULES FOR CODING THE SCREEN SECTION 57 THE DISPLAY VERB The Accept (3) 59 EXAMPLE 9.01 59 TABLE OF CONTENTS PAGE 3 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 Chapter 1: Hardware and Software INTRODUCTION The first 2 chapters provide an introduction for those who have no experience with developing applications or writing programs. Hopefully they may have some background in programming, possibly in BASIC. Otherwise the reader may go immediately to chapter 3. Computer Systems A computer, or more accurately computer system, is a set of electronic and electromechanical devices that perform a series of functions under the control of a set of instructions written by human being. This set of devices is called hardware and this set of instructions is software. This hardware under control of the proper software will compute payroll of a company, guide a spacecraft to the stars or allow Pacman to gobble up dots on a video display. Types of Computer Systems There are several types of computers systems. Mainframes are the medium to large computers used by businesses or other large organizations. They can handle many jobs running concurrently and have large memories and can handle many input devices including terminals. Many computers are smaller than mainframes and are used in specialized applications by business organizations. They handle a smaller number of jobs concurrently and have a smaller number of input devices. Microcomputers which include PCs are smaller than many computers. They have only a limited number of devices, can fit on the top of a desk, hence, are sometimes called desktype computers and usually run only one job at a given time. They are extremely useful for small personal use and also for some very specialized use by a small group even large business organizations. PAGE 1 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 Hardware The IBM-PC's are composed of several hardware components. These are the systems unit, Electronics comprising the microprocessor, either the 8088, 80186, 80286, 80386, and the newer 80486. Memory which maybe extended, expanded or conventional and a video display unit, This maybe any one of the types listed below and who knows what will come up next. Monocrome, CGA, BGA, VGA, VEGA drives the keyboard and the hard drives. Software There are 2 types of software. Applications software is written to solve a specific user problem. Examples are software that prints payroll checks or displays inventory stock information. This software is either written by the user himself using a language like COBOL, BASIC, or FORTRAN or bought off the shelf as a complete package. Software, manuals, technical support, etc. Such packaged software is generally written by an independent software company. System's Software System software does not solve specific problems, but rather makes it easier for the user to use computer system. It is generally developed by hardware or independent software companies. Examples are operating systems such as DOS, compilers such as Ansi-Standard COBOL and interpreters such as IBM Basic, saved on diskette or on hard drive and before it can be used it must first be loaded into the computers memory. This is done by typing in the proper command such as COBOL600 followed by the enter key. Programs A set of instructions written together as a single unit defines both a beginning and an end is called a program. Thus a program is a specific piece of software, system software and application software. They are more commonly known as systems programs and applications programs respectively. In this manual the latter terms will be used. Note that when a program is executing it is said to be running. In other words the program executes is the same as the program is running or the program runs. Computer people often say the job runs or the job is running. PAGE 2 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 Pseudo Code We will illustrate the concept of a program by using Pseudo Code, which is a mix of words that are valid in programs and other descriptive words that are not. While a program written in it cannot execute because of invalid words it's primary use is to make the program logic easy to understand on paper. This is shown in figure 1.1. Note the capitalized words are valid in COBOL programs. FIGURE 1.1 ______________________________________________________________ : : : ACCEPT first operator-entered number into memory. : : ACCEPT second operator-entered number into memory. : : ADD first number TO, second number GIVING result-field. : : DISPLAY result-field. : :______________________________________________________________: Pseudo Code of a segment of a program code that adds 2 numbers and displays the sum. Applications An application, more commonly known as an application system to simple system, is a specific job or sequence of jobs that run or will be run on the computer. For instance, a payroll system prints out paychecks, W2 forms, etc. An inventory system allows the operator to enter or verify stock information on a video display unit, etc. In this user's manual we will use system for a specific application, thus payroll system instead of payroll application. Developing Applications When a computer user needs an application he has a choice of either buying it off the shelf as a package "programs, manuals, tech support, etc." or developing the system himself. If he decides on the latter he first has to determine his requirements in detail and design a system that impliments the application. This is known as system design. In large organizations this systems design is generally done by the systems analyst who consults the user on his requirements and then translate them into a series of specifications that can be given to the applications programmers. They in turn translate these specifications into applications programs that can be run on the computer. PAGE 3 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 Chapter 3: ANSI-COBOL Version 6.50 Introduction COBOL "common business-oriented language" is a language developed specifically for the programming requirements of business applications. Among programming languages it is the most extensive file processing features, allowing the programmer to manipulate a large amount of data in various formats, for many types of devices. It also has the extensive report formatting features allowing the programmer, for instance, to easily print numbers with dollar signs, commas, negative signs, etc. COBOL was developed by the CONFERENCE ON DATA SYSTEMS LANGUAGES "CODASYL" COBOL committee which is made up of representatives of computer manufacturers and computer users. However, current and future standards are into the ospices of the American National Standards Institute "ANSI". Manufacturers and independent software programmers, myself included, can only use the name COBOL if the product agrees with the standard. Ansi- Standard COBOL Version 6.50 does! General Characteristics COBOL is close to English Pros in style which allows a programmer to use easily understood and self-defining words like MULTIPLING , STOP, WORKING-STORAGE, etc. Instead of the short, hard to remember symbols required in many other languages. The Language is also free form allowing the programmer to write the code in any column he wants with certain limits which the potential of making the program easier to read and understand. Ansi-Standard COBOL 6.50 COBOL Version 6.50 conforms to the low-intermediate level of American National Standards. X3.23-1974. It provides 9 out of the 12 standard COBOL functional modules which are implimented in either Level I or Level II capabilities. The 3 modules not provided are the following: 1) Communication, note this is currently being added. 2) Sort-merge, note this is currently being added. 3) Report writer, note no plans at this time to add this module. PAGE 4 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 Components of COBOL Although COBOL is close to the English Pros in style, it has it's own Syntax rules. We can think of a COBOL program as a book, consisting of 4 parts each being a COBOL division. Each division consists of 1 or more sections. Each section corresponding to a chapter in a book. Each section in turn consists of 1 or more paragraph which in turns consists of 1 or more sentences. We will now define certain COBOL terms, but we will restrict our discussion to how they are used in the most common division, the PROCEDURE DIVISION, where the logic is stated. Most definitions are however valid for other divisions, which are much easier to code than the PROCEDURE DIVISION. STATEMENTS A statement is a basic unit of the PROCEDURE DIVISION. It is a correct combination of words and symbols that specifies an action to be done, "ADD, MOVE, DIVIDE, ETC.", or a condition to be tested "IF". Unless subordinated to another statement as for example in IF conditon it is best for program and readability to code them starting in column 12. Figure 3.1 shows a segment of a program code with 6 statements. The last statement is quite long and therefore coded in 2 lines. Also for readability the continuation is indented from this. Your first exposure to typical COBOL program that the code is quite easy to understand. ______________________________________________________________________________ 12345678901234567890123456789012345678901234567890123456789012345678901234567890 IF W010-MONTH-SALES GREATER THAN 499.99 MOVE "*" TO W040-DETAIL-EXCEPTIONAL-SALES ELSE MOVE TO W040-DETAIL-EXCEPTIONAL-SALES. MOVE W010-MONTH-SALES TO W040-DETAIL-MONTH-SALES MOVE W010-ANNUAL-SALES TO W040-DETAIL-ANNUAL-SALES WRITE SALES-PERFORMANCE-LINE FROM W040-SALES-DETAIL-LINE AFTER ADVANCING W040-PRINT-SKIP LINES. EXAMPLE 3.1 _______________________________________________________________________________ PAGE 5 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 Sentence A sentence is 1 or more statements that ends in a period and is followed by a space. Notice it is followed by a space. The beginning of a sentence is always a statement that is not subordinated to another and should therefore start in column 12. This concept of a sentence is very important and the programmer is advised to terminate a statement with a period when possible. This makes a statement independent of other statements and thus avoids potential problems as you will see later on in figure 3.2. Figure 3.2 shows a segment of a program code with 4 sentences. These are actually the same statements as figure 3.1, but it now has 4 sentences from the 4 periods that end statements. Figure 3.1 only has 2 sentences. ______________________________________________________________________________ 12345678901234567890123456789012345678901234567890123456789012345678901234567890 IF W010-MONTH-CELLS GREATER THAN 499.99 MOVE "*" TO W040-DETAIL-EXCEPTIONAL-CELLS ELSE MOVE TO W040-DETAIL-EXCEPTIONAL-CELLS. MOVE W010-MONTH-CELLS TO W040-DETAIL-MONTH-CELLS. MOVE W010-ANNUAL-CELLS TO W040-DETAIL-ANNUAL-CELLS. WRITE CELLS-PERFORMANCE-LINE FROM W040-CELLS-DETAIL-LINE AFTER ADVANCING W040-PRINT-SKIP LINES. EXAMPLE 3.2 _______________________________________________________________________________ Clause A clause is part of complex statement and is only meaningful in specific statements. Examples are "GIVING" "ROUNDED". Clauses of an arithmetic statement. It maybe mandatory or optional depending on the statement. Figure 3.3 shows use of 2 clauses and a MULTIPLY statement. ______________________________________________________________________________ 12345678901234567890123456789012345678901234567890123456789012345678901234567890 MULTIPLY W010-NUMBER-OF-HOURS BY W030-HOURLY-RATE GIVING W020-WEEK-GROSS-PAY ROUNDED. EXAMPLE 3.3 ______________________________________________________________________________ PAGE 6 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 Paragraph A paragraph is 1 or more sentences that together perform a certain function maybe grouped in 1 paragraph by putting them under a paragraph header consisting of a paragraph name and a period. For program readability, this paragraph header is best coded starting in column 8. The concept of a paragraph is very important since we will learn later on that it is best to execute the logic by controlling paragraphs through the verb PERFORM. Therefore adjacent paragraphs should be seperated from each other by a line seperated. "* in column 7". Figure 3.2 does 1 function for instance print a detail line from data coming from a record. It can then be coded as a paragraph putting a paragraph header before it. Figure 3.4 is the result. ______________________________________________________________________________ 12345678901234567890123456789012345678901234567890123456789012345678901234567890 * * C060-PRINT-CELLS-REPORT-DETAIL. MULTIPLY W010-NUMBER-OF-HOURS BY W030-HOURLY-RATE GIVING W020-WEEK-GROSS-PAY ROUNDED. EXAMPLE 3.4 ______________________________________________________________________________ Section 1 or more related paragraphs maybe grouped together in one section by putting them under a section header which consists of a section name followed by the literal "SECTION" followed by period. The section ends immediately before the next section header or at the end of the program. Except for "DECLARATIVES SECTION" which also ends with the "END DECLARATIVES" statement. The concept of a section is very important in the PROCEDURES DIVISION where as we will later discuss related paragraphs are best grouped into sections. If we put the paragraph into figure 3.4 under a section header we get one section with 1 subordinate paragraph naturally we can put as many paragraphs as you want in the same section, but for readability of the program, the section header is also coded started in column 8. Also we code a line seperater which is an * in column 7 between the section header and the paragraph header. The result is in figure 3.5. PAGE 7 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 ______________________________________________________________________________ 12345678901234567890123456789012345678901234567890123456789012345678901234567890 * * C000-PRINT-CELLS-REPORT SECTION. * C060-PRINT-CELLS-REPORT-DETAIL. MULTIPLY W010-NUMBER-OF-HOURS BY W030-HOURLY-RATE GIVING W020-WEEK-GROSS-PAY ROUNDED. EXAMPLE 3.5 ______________________________________________________________________________ STATEMENT FORMAT Each statement in the language has a general format and the programmer has to use the prescribed rules for each statement regarding spelling "reserved words must be spelled correctly". Providing the names of data to be used and the order of the clauses in the statement. To a large extent the rules of format follow common sense. For instance, program logic is coded with statements which start with a verb like "ADD, MOVE, MULTIPLY, ETC." followed by the operend used by the verbs followed if any by optional clauses. For instances, to multiply 2 numbers we code: MULTIPLY first-operend BY second-operend GIVING product-field ROUNDED ON SIZE ERROR, imperative statements. The 2 operends are multiplied and the product is placed in the product field if the GIVING option is specified. It maybe rounded off and it may not fit into high order left most part of the product field. The imperative statements will be executed instead of the next following statement. Note that the GIVING, ROUNDED, and ON SIZE ERROR are optional clauses. Before we go any further, examine fig. 3.6. PAGE 8 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 ______________________________________________________________________________ 12345678901234567890123456789012345678901234567890123456789012345678901234567890 IDENTIFICATION DIVISION. * PROGRAM-ID. EXMP36. * *********************************************************** * DATE-WRITTEN. 08/13/90. * *********************************************************** * ENVIRONMENT DIVISION. * DATA DIVISION. * WORKING-STORAGE SECTION. 01 HELLO-WORLD PIC X(20) VALUE "Hello world". * PROCEDURE DIVISION. * DISPLAY HELLO-WORLD. STOP RUN. EXAMPLE 3.6 ______________________________________________________________________________ The program logic is in the PROCEDURE DIVISION. At the moment the reader should concern himself only with the last 2 lines. The DISPLAY shows HELLO-WORLD from a COBOL program on the video display and the STOP RUN which as a name suggests stops execution of the program. Thus you now know 2 verbs, DISPLAY and STOP in COBOL. As you see they are self defining. PAGE 9 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 COBOL Character Set With the exception of non-numeric literals and comments where the entire COBOLs character set maybe used only 52 characters are allowed in a COBOL program. They are : 1) letters A-Z and a-z. 2) spaces or blanks. 3) digits 0-9. 4) the following special characters: +, -,*, =, >, <, $, , , ;, ., ", (, ), ', -. If the computer detects any other characters, if not found under these exceptions noted, an error will be detected. Characters Used in Words A word is composed of a combination of not more than 30 characters. It cannot begin or end with a hyphen and the valid characters are letters A-Z, digits 0-9, and hyphen. Characters Used for Punctuation The following characters are used for punctuation: (, ), ,, ;,. Rules for Punctuation Punctuation characters are used according to the following rules. 1) When used as punctuation a period, semicolon, or comma must be followed by a space. 2) At least one space must appear between 2 successive words in literals. 3) Relation characters (=, >, <) must always be proceeded by a space and followed by another space. 4) You may optionally use a comma as a seperater between successive oprands of a statement or between 2 subscripts. 5) You may optionally use a semicolon or comma to seperate a series of statements or clauses. 6) You may use an apostrophe in place of a quotation mark when delementing non-numeric literals. Characters Used in Conditions The following characters are used in conditions: 1) The greater than sign. 2) The less than sign. 3) The equal sign. PAGE 10 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 Characters Used in Arithmetic Arithmetic expressions are used in the COMPUTE statement and they make use of the arithmetic operators. Evaluation is done in the following order: 1) Expressions within the parenthesis are evaluated first from the inner most pair to the outer most pair. 2) Within a pair of parenthesis or if there is none the order is according to the following operators: a) Unary "+ or - in the variable or number". b) Expodentation "**". c) Mulitiplication and division. d) Addition and subtraction. 3) For operators with the same order mulitplication and division or addition and subtraction evaluation is left to right. Characters Used for Print Editing Editing characters are replaced characters in a data item to be printed. They are used to optimize a presentation of the data item in a report. They are: 1) 9 numeric character. 2) V decimal point. 3) , comma. 4) Z zero suppress. 5) * check protection. 6) $ currency sign. 7) + plus. 8) - minus. 9) B blank. 10) 0 zero. 11) / slash. 12) CR credit. 13) DR debit. PAGE 11 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 Types of Words Reserved words are those that have a specific meaning in COBOL and they must be spelled correctly and used in only the way that they were intended. Examples are "ADVANCING, MOVE, PAGE" etc. Program refined words, non-reserved words, are coded by the programmer for the following uses: 1) data names, 2) files names, 3) condition names, 4) procedure names. Reserved Words Reserved words have specific meanings in COBOL and therefore use only according to proper Syntax rules. These words must be spelled correctly. However, reserved words enclosed in quotation marks become non-numerical literals and are not reserved words. There are 3 types of reserved words. 1) Key word - key word is a word which is required in the statement. There are 3 types: a) verbs, such as ADD, MOVE, READ. b) required words that appear in certain statements, such as TO and the ADD statement. c) words that have specific functional meaning, such as PAGE, ZERO, POSITIVE. 2) Optional words - an optional word may or may not be included in a statement. Examples are GIVING, ROUNDED, and ON SIZE ERROR, which are clauses in arithmetic statements. 3) Connectives - connective is a word that joins or connects 2 adjacent words. There are 2 types: a) qualifier connective. This is "OF" which associates a data name, condition name or paragraph name with it's qualifier. b) logical connectives. These are words used in compound combinations. They are AND and OR. PAGE 12 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 RESERVED WORDS LIST =================== ACCEPT BLANK CONFIGURATION DYNAMIC ACCESS BLINK CONTAINS ELSE ADD BLOCK COPY EMPTY-CHECK ADVANCING BOTTOM COUNT END AFTER BY CURRENCY END-OF-PAGE ALL CALL DATA ENVIRONMENT ALPHABETIC CHAIN DATE EOP ALTER CHAINING DATE-COMPILED EQUAL AND CHARACTER DATE-WRITTEN ERASE ARE CHARACTERS DAY ERROR AREA CLOSE DEBUGGING ESCAPE AREAS CODE-SET DECIMAL-POINT EVERY ASCENDING COL DECLARATIVES EXCEPTION ASCII COLLATING DELETE EXHIBIT ASSIGN COLUMN DELIMITED EXIT AT COMMA DELIMITER EXTEND AUTHOR COMP DEPENDING FD AUTO COMP-0 DESCENDING FILE AUTO-SKIP COMP-3 DISK FILE-CONTROL BACKGROUND-COLOR COMPUTATIONAL DISPLAY FILE-ID BEEP COMPUTATIONAL-0 DIVIDE FILLER BEFORE COMPUTATIONAL-3 DIVISION FIRST BELL COMPUTE DOWN FOOTING FOR IS NAMED POINTER FOREGROUND-COLOR JUST NATIVE POSITIVE FROM JUSTIFIED NEGATIVE PRINTER FULL KEY NEXT PROCEDURE GIVING LABEL NO PROCEDURES GO LEADING NO-ECHO PROCEED GREATER LEFT NOT PROGRAM HIGH-VALUE LEFT-JUSTIFY NUMBER PROGRAM-ID HIGH-VALUES LENGTH-CHECK NUMERIC PROMPT HIGHLIGHT LESS OCCURS Q-RW-Q I-O LIN OFF QUOTE I-O-CONTROL LINAGE OMITTED QUOTES IDENTIFICATION LINAGE-COUNTER ON RANDOM IF LINE OPEN READ INDEX LINES OR READY INDEXED LINKAGE ORGANIZATION RECORD INITIAL LOCK OUTPUT RECORDS INPUT LOW-VALUE OVERFLOW REDEFINES INPUT-OUTPUT LOW-VALUES PAGE RELATIVE INSPECT MERGE PERFORM RELEASE INSTALLATION MODE PIC REPLACING INTO MOVE PICTURE REQUIRED INVALID MULTIPLY PLUS RERUN PAGE 13 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 RESERVE SIGN TO ZEROES RESET SIZE TOP ZEROS RESTART-FILE SORT TRACE RETURN SORT-MERGED TRAILING REVERSE-VIDEO SOURCE-COMPUTER TRAILING-SIGN REWRITE SPACE UNDERLINE RIGHT SPACE-FILL UNSTRING RIGHT-JUSTIFY SPACES UNTIL ROUNDED SPECIAL-NAMES UP RUN STANDARD UPDATE SAME STANDARD-1 UPON SCREEN START USAGE SD STATUS USE SEARCH STOP USING SECTION STRING VALUE SECURE SUBTRACT VALUES SECURITY SYNC VARYING SELECT SYNCHRONIZED WHEN SENTENCE TALLYING WITH SEPARATE THAN WORKING-STORAGE SEQUENCE THROUGH WRITE SEQUENTIAL THRU ZERO SET TIME ZERO-FILL PAGE 14 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 Non-reserved words are coded according to these rules: 1) Only the 26 letters upper and lower case, digits 0-9, and hyphen can be used. 2) All words must begin with a letter except procedure names which may consist entirely of digits. 3) A word may not begin or end with a hyphen. 4) A word can have from 1-30 characters. 5) A data name or condition name does not have to be unique as long as they may be qualified with unique names of a higher level. 6) A word ends with a space or a punctuation mark. Data Format Data used in programs maybe represented in 4 ways. They are: 1) Display. The data consists of a combination without the numeric or special characters which each character using 1 byte of memory. If the data contains only numbers it maybe used in arithmetic operation. The "USAGE IS DISPLAY" clause maybe specified or omitted. Display is a default for the usage clause. 2) Packed decimal. The data consists of digits with 2 digits packed together in 1 byte except the right most digit which is packed with the sign. This field is used for arithmetic or numeric move operations. The "USAGE IS COMP-3 | COMPUTATIONAL-3". Clause must be specified. 3) Binary item. The data consists of binary numbers. The "USAGE IS COMP-0 | COMPUTATIONAL-0". Clause must be specified. 4) Index. The data item which is defined with the usage is index clause but without a picture clause is used as an index data item in a relational condition as a varying item and performing varying statement or in place of a subscript. Elementary Data Items A data item that is not further subdivided into still other items within a program is an elementary data item. It is therefore the lowest level of data item in a group. Examples are employee numbers, gross salary, etc. The maximum level of elementary data item is 4,095 bytes. PAGE 15 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 Group Data Item A data item that is further subdivided into still other data items is a group item. For instance, the group item date of birth may consist of 3 elementary data items - month, day, year. The elementary data item or the group item maybe used in statements. The maximum length of a group data item is 4,095 bytes. The exception are at leve-01 group items records which are not checked for length so that long tables can be used in programs. However, statements and procedure division cannot use data items longer than 4,095 byte limit. There is no problem with tables because statements are always referred to individual elements in the table, not the whole table. Records Elementary and group data items that belong to a single entity maybe grouped together under a single 01 level record. For instance, all data items employee number, gross salary, date hired, etc. belong to one employee may be grouped into a single employee record. Files A group of records maybe written or grouped together in a single file. For instance, all employee records for all employees in a company belong to the employee master file. PAGE 16 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 The COBOL Coding Form In good ole days when cards were used to enter programs programmers used to write COBOL source programs on these coding forms before punching them or having them punched by keypunch operators. Now a days most programmers enter their code directly on the screen via text editor thus negating the need for coding forms. HOWEVER!!! You still must adhere to the coding form rules and they are: 1) Columns 1-6 were originally used to enter line numbers. The reason if some clot was to drop the cards they can easily be sorted again. Today you may or may not enter the line numbers, it does not make any difference. 2) Column 7 is used 4 ways. They are: a) if an asterisk is entered the line is considered a comment. b) if a slash is entered it will cause a page eject in the program listing. c) if non-numerical literal is to be continued on the next line a hyphen must be entered. d) if the letter D is entered than the line is compiled as part of the program IF AND ONLY IF the statement camps with debugging mode. Clauses included in the SOURCE-COMPUTER paragraph of the CONFIGURATION SECTION in the ENVIRONMENT DIVISION. 3) Columns 8-11 define area A a statement that starts a group of related statements must start anywhere within this area. Examples are division headers, section headers, 01 level group items, paragraph names, etc. However, for the sake of readability you should always start them in Column A. 4) Columns 12-77 define area B all other statements that cannot start in area A must start here. 5) Columns 78-80 are not processed by this compiler. 6) For the PC, characters may be entered in either lowercase or uppercase. PAGE 17 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 BASIC COBOL STATEMENTS INTRODUCTION Before we go into the details of coding, let us take a few more simpilified program examples that will familiarize us with many of the concepts that we will be using later on. These concepts will be very useful when we attempt to write larger programs. Let me remind you that you have already seen the two verbs DISPLAY and STOP. PAGE 18 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 ACCEPT statement (format 2) The ACCEPT verb may be used to allow the operator to enter data on the console display in its normal scrolling mode. This version (format 2) is generally used if there is no need to have data entered on a formatted screen (formatted screens are needed if a lot of data is entered on the same screen). The program is shown in fig. 4.1. Look at line 34 in the PROCEDURE DIVISION which shows that the program accepts data from the operator. The data then goes into field W005- MESSAGE-FIELD, which line 28 shows can accommodate as many as thirty-two characters. The same data is then displayed back on the video display unit at line 35. Note that each complete statement ends with a period, making it a sentence. PROGRAM LISTING 4.01 -------------------- PROG401 COB 12:00:14 02-Sep-90 PAGE 1 Line Number Source Line ANSI 74-85 Standard Cobol V.6.0 (c)1990. 1 IDENTIFICATION DIVISION. 2 * 3 PROGRAM-ID. PROG401. 4 * 5 *************************************************** 6 * * 7 * 1. DATE-WRITTEN. 08/01/90. * 8 * * 9 * 2. THIS PROGRAM DISPLAYS ON THE CONSOLE DISPLAY * 10 * A MESSAGE ENTERED BY THE OPERATOR. * 11 * * 12 *************************************************** 13 * 14 * 15 ENVIRONMENT DIVISION. 16 * 17 * 18 DATA DIVISION. 19 * 20 * 21 **************************************************** 22 * * 23 WORKING-STORAGE SECTION. 24 * * 25 **************************************************** 26 * 27 * 28 01 W005-MESSAGE-FIELD PIC X(32). 29 * 30 * 31 PROCEDURE DIVISION. 32 * 33 DISPLAY-ACCEPTED-MESSAGE. PAGE 19 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 34 ACCEPT W005-MESSAGE-FIELD. 35 DISPLAY W005-MESSAGE-FIELD. 36 STOP RUN. -------------------------------------------------------- The PRINTER DISPLAY STATEMENT We have seen that the DISPLAY verb can display information on the video display unit. Actually this verb is very powerful and can also be used to display information on the printer. Note that this is useful for displaying a small amount of information only and should not replace the technique of using the printer as a afile which presents in a nice format a very large amount of information. also, this feature should not be intersperced with the printing of reports since it will get mixed with the later. The program is shown in fig.4.2. Note lines 17 to 21. These specify that the printer will be used for displayed information. Lines 42 to 44 are similar to lines 34 to 36 of fig.4.1 execpt that the DISPLAY statement now includes the operands "UPON PRINTER-DISPLAY". This ties up with statement 21 and the information entered by the operator on the console display is printed out at line 43. The result is fig.4.3. Note that the operator entered "THIS MESSAGE IS OPERATOR ENTERED". PROGRAM LISTING 4.2 ------------------- PROG402 COB 12:18:22 02-Sep-90 PAGE 1 Line Number Source Line ANSI 74-85 Standard Cobol V.6.0 (c)1990. 1 IDENTIFICATION DIVISION. 2 * 3 PROGRAM-ID. PROG402. 4 * 5 *************************************************** 6 * * 7 * 1. DATE-WRITTEN. 08/01/90. * 8 * * 9 * 2. THIS PROGRAM DISPLAYS ON THE PRINTER * 10 * A MESSAGE ENTERED BY THE OPERATOR. * 11 * * 12 *************************************************** 13 * 14 * 15 ENVIRONMENT DIVISION. 16 * 17 CONFIGURATION SECTION. 18 * 19 SPECIAL-NAMES. 20 * 21 PRINTER IS PRINTER-DISPLAY. PAGE 20 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 22 * 23 * 24 DATA DIVISION. 25 * 26 * 27 **************************************************** 28 * * 29 WORKING-STORAGE SECTION. 30 * * 31 **************************************************** 32 * 33 * 34 01 W005-MESSAGE-FIELD PIC X(32). 35 * 36 * 37 PROCEDURE DIVISION. 38 * 39 DISPLAY-ACCEPTED-MESSAGE. 40 DISPLAY "PROGRAM PROG402: PRINT DISPLAY OUTPUT:" 41 UPON PRINTER-DISPLAY. 42 ACCEPT W005-MESSAGE-FIELD. 43 DISPLAY W005-MESSAGE-FIELD UPON PRINTER-DISPLAY. 44 STOP RUN. -------------------------------------------------------- EXAMPLE 4.3 PROGRAM PROG402: PRINT DISPLAY OUTPUT: THIS MESSAGE IS OPERATOR ENTERED -------------------------------------------------------- THE MOVE STATEMENT The MOVE verb moves data to a data field. The data may be a literal specified in the statement or another data field. The program is shown in fig. 4.4. The reader should look at lines 38 and 40. These are the fields involved in the MOVE statements in lines 49 and 50. The operator will enter the data into the field "W005- ACCEPT-MESSAGE-FIELD" and this is moved to the field "W005-DISPLAY-MESSAGE-FIELD". The rest are the same as in PROG402. The result is shown in fig.4.5. PROGRAM LISTING 4.4 ------------------- PROG404 COB 12:34:20 02-Sep-90 PAGE 1 Line Number Source Line ANSI 74-85 Standard Cobol V.6.0 (c)1990. 1 IDENTIFICATION DIVISION. 2 * 3 PROGRAM-ID. PROG404. 4 * 5 *************************************************** PAGE 21 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 6 * * 7 * 1. DATE-WRITTEN. 08/01/90. * 8 * * 9 * 2. THIS PROGRAM DISPLAYS ON THE PRINTER * 10 * A MESSAGE ENTERED BY THE OPERATOR. * 11 * * 12 * 3. THE MESSAGE IS INITIALLY ENTERED INTO ONE * 13 * WHICH IS THEN MOVED TO ANOTHER FIELD BEFORE * 14 * BEING PRINTED ON THE PRINTER. * 15 * * 16 *************************************************** 17 * 18 * 19 ENVIRONMENT DIVISION. 20 * 21 CONFIGURATION SECTION. 22 * 23 SPECIAL-NAMES. 24 * 25 PRINTER IS PRINTER-DISPLAY. 26 * 27 * 28 DATA DIVISION. 29 * 30 * 31 **************************************************** 32 * * 33 WORKING-STORAGE SECTION. 34 * * 35 **************************************************** 36 * 37 * 38 01 W005-ACCEPT-MESSAGE-FIELD PIC X(32). 39 * 40 01 W005-DISPLAY-MESSAGE-FIELD PIC X(32). 41 * 42 * 43 PROCEDURE DIVISION. 44 * 45 DISPLAY-ACCEPTED-MESSAGE. 46 DISPLAY "PROGRAM PROG404: PRINT DISPLAY OUTPUT:" 47 UPON PRINTER-DISPLAY. 48 ACCEPT W005-ACCEPT-MESSAGE-FIELD. 49 MOVE W005-ACCEPT-MESSAGE-FIELD 50 TO W005-DISPLAY-MESSAGE-FIELD. 51 DISPLAY W005-DISPLAY-MESSAGE-FIELD 52 UPON PRINTER-DISPLAY. 53 STOP RUN. -------------------------------------------------------- EXAMPLE 4.5 PROGRAM PROG404: PRINT DISPLAY OUTPUT: THIS MESSAGE IS OPERATOR ENTERED -------------------------------------------------------- PAGE 22 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 THE ADD STATEMENT The ADD verb adds two numbers and as options rounds off the sum, checks it for overflow, or places it into a specific field. Here, we will take up the most basic version of the statement where we add two numbers (contained in the two operands) and the sum is placed in the second operand and thus replaces its original value. The program is fig.4.6. Lines 34 and 36 specify the operands to be used and their respective values. Line 42 does the ADD operation. The result is fig.4.7. PROGRAM LISTING 4.6 -------------------- PROG406 COB 12:49:48 02-Sep-90 PAGE 1 Line Number Source Line ANSI 74-85 Standard Cobol V.6.0 (c)1990. 1 IDENTIFICATION DIVISION. 2 * 3 PROGRAM-ID. PROG406. 4 * 5 *************************************************** 6 * * 7 * 1. DATE-WRITTEN. 08/01/90. * 8 * * 9 * 2. THIS PROGRAM DISPLAYS ON THE PRINTER * 10 * A VALUE COMPUTED FROM AN ADD OPERATION. * 11 * * 12 *************************************************** 13 * 14 * 15 ENVIRONMENT DIVISION. 16 * 17 CONFIGURATION SECTION. 18 * 19 SPECIAL-NAMES. 20 * 21 PRINTER IS PRINTER-DISPLAY. 22 * 23 * 24 DATA DIVISION. 25 * 26 * 27 **************************************************** 28 * * 29 WORKING-STORAGE SECTION. 30 * * 31 **************************************************** 32 * 33 * 34 01 W005-FIRST-OPERAND PIC 9 VALUE 2. 35 * 36 01 W005-SECOND-OPERAND PIC 99 VALUE 12. 37 * PAGE 23 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 38 * 39 PROCEDURE DIVISION. 40 * 41 PRINT-COMPUTED-VALUE. 42 ADD W005-FIRST-OPERAND TO W005-SECOND-OPERAND. 43 DISPLAY "PROGRAM PROG406: THE SUM OF 2 + 12 IS:" 44 UPON PRINTER-DISPLAY. 45 DISPLAY W005-SECOND-OPERAND UPON PRINTER-DISPLAY. 46 STOP RUN. --------------------------------------------------------- EXAMPLE 4.7 PROGRAM PROG406: THE SUM OF 2 + 12 IS: 14 ---------------------------------------------------------- THE SUBTRACT STATEMENT The SUBTRACT verb subtracts two numbers and as options rounds off the result, checks it for overflow, or places it into a specific field. Here, we will take up the most basic version of the statement where we subtract two numbers (contained in the two operands ) and the result is placed in the second operand ( the minuend) and thus replaces the original value. The program is shown in fig.4.8. Line 42 subtracts the two numbers, which is then displayed on the printer. The result is fig.4.9. PROGRAM LIST 4.8 ---------------- PROG408 COB 13:01:10 02-Sep-90 PAGE 1 Line Number Source Line ANSI 74-85 Standard Cobol V.6.0 (c)1990. 1 IDENTIFICATION DIVISION. 2 * 3 PROGRAM-ID. PROG408. 4 * 5 *************************************************** 6 * * 7 * 1. DATE-WRITTEN. 08/01/90. * 8 * * 9 * 2. THIS PROGRAM DISPLAYS ON THE PRINTER * 10 * A VALUE COMPUTED FROM A SUBTRACT OPERATION. * 11 * * 12 *************************************************** 13 * 14 * 15 ENVIRONMENT DIVISION. 16 * 17 CONFIGURATION SECTION. 18 * 19 SPECIAL-NAMES. 20 * PAGE 24 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 21 PRINTER IS PRINTER-DISPLAY. 22 * 23 * 24 DATA DIVISION. 25 * 26 * 27 **************************************************** 28 * * 29 WORKING-STORAGE SECTION. 30 * * 31 **************************************************** 32 * 33 * 34 01 W005-SUBTRAHEND PIC 9 VALUE 2. 35 * 36 01 W005-MINUEND PIC 99 VALUE 12. 37 * 38 * 39 PROCEDURE DIVISION. 40 * 41 PRINT-COMPUTED-VALUE. 42 SUBTRACT W005-SUBTRAHEND FROM W005-MINUEND. 43 DISPLAY "PROGRAM PROG408: THE RESULT OF 12 - 2 IS:" 44 UPON PRINTER-DISPLAY. 45 DISPLAY W005-MINUEND UPON PRINTER-DISPLAY. 46 STOP RUN. -------------------------------------------------------- EXAMPLE 4.9 PROGRAM PROG408: THE RESULT OF 12 - 2 IS: 10 --------------------------------------------------------- THE MULTIPLY STATEMENT The MULTIPLY verb multiplies two numbers and as options rounds off the product, checks it for overflow, or puts it into a specific field. Here, we will take up the most basic version of the statement where we multiply two numbers (contained in the two operands) and the product is placed in the second operand ( the multiplier) and thus replaces its original value. The program is shown in fig.4.10. Line 42 does the multiplication which is then printed out. The result is fig.4.11. PROGRAM LIST 4.10 ----------------- PROG410 COB 13:13:40 02-Sep-90 PAGE 1 Line Number Source Line ANSI 74-85 Standard Cobol V.6.0 (c)1990. 1 IDENTIFICATION DIVISION. 2 * 3 PROGRAM-ID. PROG410. PAGE 25 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 4 * 5 *************************************************** 6 * * 7 * 1. DATE-WRITTEN. 08/01/90. * 8 * * 9 * 2. THIS PROGRAM DISPLAYS ON THE PRINTER * 10 * A VALUE COMPUTED FROM A MULTIPLY OPERATION. * 11 * * 12 *************************************************** 13 * 14 * 15 ENVIRONMENT DIVISION. 16 * 17 CONFIGURATION SECTION. 18 * 19 SPECIAL-NAMES. 20 * 21 PRINTER IS PRINTER-DISPLAY. 22 * 23 * 24 DATA DIVISION. 25 * 26 * 27 **************************************************** 28 * * 29 WORKING-STORAGE SECTION. 30 * * 31 **************************************************** 32 * 33 * 34 01 W005-MULTIPLICAND PIC 9 VALUE 2. 35 * 36 01 W005-MULTIPLIER PIC 99 VALUE 12. 37 * 38 * 39 PROCEDURE DIVISION. 40 * 41 PRINT-COMPUTED-VALUE. 42 MULTIPLY W005-MULTIPLICAND BY W005-MULTIPLIER. 43 DISPLAY "PROGRAM PROG410: THE PRODUCT OF 2 * 12 IS:" 44 UPON PRINTER-DISPLAY. 45 DISPLAY W005-MULTIPLIER UPON PRINTER-DISPLAY. 46 STOP RUN. --------------------------------------------------------- EXAMPLE 4.11 PROGRAM PROG410: THE PRODUCT OF 2 * 12 IS: 24 ---------------------------------------------------------- PAGE 26 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 THE DIVIDE STATEMENT The DIVIDE verb divides two numbers and as options rounds off the quotient, checks it for overflow, or places it into a specific field. Here, we will take up the most basic version of the statement where we divide two numbers and the quotient is placed in the second operand (the dividend) and thus replaces its original value. The program is shown in fig.4.12. Line 42 divides the two numbers and the result is then printed out. The result is fig.4.13. You will notice that the result is 06, not simply 6. PROGRAM LIST 4.12 ------------------- PROG412 COB 13:25:31 02-Sep-90 PAGE 1 Line Number Source Line ANSI 74-85 Standard Cobol V.6.0 (c)1990. 1 IDENTIFICATION DIVISION. 2 * 3 PROGRAM-ID. PROG412. 4 * 5 *************************************************** 6 * * 7 * 1. DATE-WRITTEN. 08/01/90. * 8 * * 9 * 2. THIS PROGRAM DISPLAYS ON THE PRINTER * 10 * A VALUE COMPUTED FROM A DIVIDE OPERATION. * 11 * * 12 *************************************************** 13 * 14 * 15 ENVIRONMENT DIVISION. 16 * 17 CONFIGURATION SECTION. 18 * 19 SPECIAL-NAMES. 20 * 21 PRINTER IS PRINTER-DISPLAY. 22 * 23 * 24 DATA DIVISION. 25 * 26 * 27 **************************************************** 28 * * 29 WORKING-STORAGE SECTION. 30 * * 31 **************************************************** 32 * 33 * 34 01 W005-DIVISOR PIC 9 VALUE 2. 35 * PAGE 27 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 36 01 W005-DIVIDEND PIC 99 VALUE 12. 37 * 38 * 39 PROCEDURE DIVISION. 40 * 41 PRINT-COMPUTED-VALUE. 42 DIVIDE W005-DIVISOR INTO W005-DIVIDEND. 43 DISPLAY "PROGRAM PROG412: THE QUOTIENT OF 12 / 2 IS:" 44 UPON PRINTER-DISPLAY. 45 DISPLAY W005-DIVIDEND UPON PRINTER-DISPLAY. 46 STOP RUN. --------------------------------------------------------- EXAMPLE 4.13 PROGRAM PROG412: THE QUOTIENT OF 12 / 2 IS: 06 --------------------------------------------------------- THE GIVING CLAUSE We have so far used the four arithmetic operations where we allowed the result to replace one of the original operands. This may be all right for some programs, but in others you may want to preserve the original numbers because you may need them later on. We accomplish this by including the optional GIVING clause which specifies a data item that will contain the result of the arithmetic operation. An example is fig.4.14. Line 40 defines the data item that will receive the result of the DIVIDE operation, which is coded in line 46. This is the data item that we will also display on the printer. The result is fig.4.15. PROGRAM LISTING 4.14 --------------------- PROG414 COB 13:37:26 02-Sep-90 PAGE 1 Line Number Source Line ANSI 74-85 Standard Cobol V.6.0 (c)1990. 1 IDENTIFICATION DIVISION. 2 * 3 PROGRAM-ID. PROG414. 4 * 5 *************************************************** 6 * * 7 * 1. DATE-WRITTEN. 08/01/90. * 8 * * 9 * 2. THIS PROGRAM DISPLAYS ON THE PRINTER * 10 * A VALUE COMPUTED FROM A DIVIDE OPERATION. * 11 * * 12 * 3. THE QUOTIENT IS PLACED INTO A DIFFERENT FIELD* 13 * * 14 *************************************************** 15 * 16 * PAGE 28 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 17 ENVIRONMENT DIVISION. 18 * 19 CONFIGURATION SECTION. 20 * 21 SPECIAL-NAMES. 22 * 23 PRINTER IS PRINTER-DISPLAY. 24 * 25 * 26 DATA DIVISION. 27 * 28 * 29 **************************************************** 30 * * 31 WORKING-STORAGE SECTION. 32 * * 33 **************************************************** 34 * 35 * 36 01 W005-DIVISOR PIC 9 VALUE 2. 37 * 38 01 W005-DIVIDEND PIC 99 VALUE 12. 39 * 40 01 W005-QUOTIENT PIC 9. 41 * 42 PROCEDURE DIVISION. 43 * 44 PRINT-COMPUTED-VALUE. 45 DIVIDE W005-DIVISOR INTO W005-DIVIDEND GIVING W005-QUOTIENT. 46 DISPLAY "PROGRAM PROG414: THE QUOTIENT OF 12 / 2 IS:" 47 UPON PRINTER-DISPLAY. 48 DISPLAY W005-QUOTIENT UPON PRINTER-DISPLAY. 49 STOP RUN. --------------------------------------------------------- EXAMPLE 4.15 PROGRAM PROG414: THE QUOTIENT OF 12 / 2 IS: 6 --------------------------------------------------------- THE ROUNDED CLAUSE In certain arithmetic operations, especially division and sometimes multiplication with decimals, there may be extra digits in the result to the right of the decinal point that cannot be accommodated in the data item that holds this result. ANSI-COBOL automatically truncates these digits from the result without rounding off the remaining loworder (rightmost) digit, unless the optional ROUNDED clause is included. Fig. 4.16 shows the differnce between division without rounding and one with rounding. Both versions will be displayed for comparison. Lines 50 to 53 shows division without rounding, followed by the corresponding display; and lines 54 to 58, those with rounding. Incidentally, line 52 shows how a non-numeric literal is continued in the next line. The result is fig.4.17. The quotient of 5/3 PAGE 29 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 is 1 if not rounded, and 2 if rounded. Since the rounded version is closer to the true answer, this option should always be used if truncation can occur. PROGRAM LISTING 4.16 -------------------- PROG416 COB 14:01:37 02-Sep-90 PAGE 1 Line Number Source Line ANSI 74-85 Standard Cobol V.6.0 (c)1990. 1 IDENTIFICATION DIVISION. 2 * 3 PROGRAM-ID. PROG416. 4 * 5 ********************************************************* 6 * * 7 * 1. DATE-WRITTEN. 08/01/90. * 8 * * 9 * 2. THIS PROGRAM DISPLAYS ON THE PRINTER * 10 * A VALUE COMPUTED FROM A DIVIDE OPERATION. * 11 * * 12 * 3. THE QUOTIENT IS PLACED INTO A DIFFERENT FIELD * 13 * * 14 * 4. THE DIVIDE OPERATION AND DISPLAY WILL BE DONE TWICE* 15 * A) TRY #1 - QUOTIENT IS NOT ROUNDED OFF. * 16 * B) TRY #2 - QUOTIENT IS ROUNDED OFF. * 17 * * 18 ********************************************************* 19 * 20 * 21 ENVIRONMENT DIVISION. 22 * 23 CONFIGURATION SECTION. 24 * 25 SPECIAL-NAMES. 26 * 27 PRINTER IS PRINTER-DISPLAY. 28 * 29 * 30 DATA DIVISION. 31 * 32 * 33 **************************************************** 34 * * 35 WORKING-STORAGE SECTION. 36 * * 37 **************************************************** 38 * 39 * 40 01 W005-DIVISOR PIC 9 VALUE 3. 41 * 42 01 W005-DIVIDEND PIC 9 VALUE 5. 43 * 44 01 W005-QUOTIENT PIC 9. 45 * 46 * PAGE 30 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 47 PROCEDURE DIVISION. 48 * 49 PRINT-COMPUTED-VALUE. 50 DIVIDE W005-DIVISOR INTO W005-DIVIDEND GIVING W005-QUOTIENT. 51 DISPLAY "PROGRAM PROG414: THE QUOTIENT OF 5 / 3 UNROUNDED IS 52 - ":" UPON PRINTER-DISPLAY. 53 DISPLAY W005-QUOTIENT UPON PRINTER-DISPLAY. 54 DIVIDE W005-DIVISOR INTO W005-DIVIDEND 55 GIVING W005-QUOTIENT ROUNDED. PROG416 COB 14:01:37 02-Sep-90 PAGE 2 Line Number Source Line ANSI 74-85 Standard Cobol V.6.0 (c)1990. 56 DISPLAY "PROGRAM PROG414: THE QUOTIENT OF 5 / 3 ROUNDED IS:" 57 UPON PRINTER-DISPLAY. 58 DISPLAY W005-QUOTIENT UPON PRINTER-DISPLAY. 59 STOP RUN. ----------------------------------------------------------- EXAMPLE 4.17 PROGRAM PROG416: THE QUOTIENT OF 5 / 3 UNROUNDED IS: 1 PROGRAM PROG416: THE QUOTIENT OF 5 / 3 ROUNDED IS: 2 ---------------------------------------------------------- THE PERFORM STATEMENT The PERFORM verb executes a set of one or more contiguous sections or paragraphs, then returns control to the statement following the PERFORM. It is thus a temporary branch from the current set of statements being executed. It is an extremely useful verb and is generally used to control the program logic by selecting which statements are to be executed at any given time. The program is shown in fig.4.20. PROGRAM LISTING 4.20 -------------------- PROG420 COB 14:35:22 02-Sep-90 PAGE 1 Line Number Source Line ANSI 74-85 Standard Cobol V.6.0 (c)1990. 1 IDENTIFICATION DIVISION. 2 * 3 PROGRAM-ID. PROG420. 4 * 5 ENVIRONMENT DIVISION. 6 * 7 CONFIGURATION SECTION. 8 * 9 SPECIAL-NAMES. PAGE 31 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 10 * 11 PRINTER IS PRINTER-DISPLAY. 12 * 13 * 14 DATA DIVISION. 15 * 16 * 17 WORKING-STORAGE SECTION. 18 * 19 01 W005-DIVISOR PIC 9 VALUE 2. 20 * 21 01 W005-DIVIDEND PIC 99 VALUE 12. 22 * 23 01 W005-QUOTIENT PIC 9. 24 * 25 * 26 PROCEDURE DIVISION. 27 * 28 MAIN-LINE-LOGIC. 29 PERFORM PRINT-COMPUTED-VALUE. 30 STOP RUN. 31 * 32 * 33 PRINT-COMPUTED-VALUE. 34 DIVIDE W005-DIVISOR INTO W005-DIVIDEND GIVING W005-QUOTIENT. 35 DISPLAY "12/2 IS". 36 DISPLAY W005-QUOTIENT. --------------------------------------------------------- THE ON SIZE ERROR CLAUSE If after decimal point alignment and rounding, the high- order (left-most) portion of the result cannot fit in the data item for the result, the "size error" condition occurs. If the ON SIZE ERROR option is not used in the arithmetic statement, the result is unpredictable. Otherwise, the imperative statements that fall under the ON SIZE ERROR clause will be executed. An example is fig.4.22. PROGRAM LISTING 4.22 -------------------- PROG422 COB 14:36:08 02-Sep-90 PAGE 1 Line Number Source Line ANSI 74-85 Standard Cobol V.6.0 (c)1990. 1 IDENTIFICATION DIVISION. 2 * 3 PROGRAM-ID. CHAP422. 4 * 5 ENVIRONMENT DIVISION. 6 * 7 CONFIGURATION SECTION. 8 * 9 SPECIAL-NAMES. PAGE 32 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 10 * 11 PRINTER IS PRINTER-DISPLAY. 12 * 13 DATA DIVISION. 14 * 15 WORKING-STORAGE SECTION. 16 * 17 01 W005-DIVISOR PIC 9 VALUE 0. 18 * 19 01 W005-DIVIDEND PIC 99 VALUE 5. 20 * 21 01 W005-QUOTIENT PIC 9. 22 * 23 * 24 PROCEDURE DIVISION. 25 * 26 MAIN-LINE-LOGIC. 27 PERFORM PRINT-COMPUTED-VALUE. 28 STOP RUN. 29 * 30 * 31 PRINT-COMPUTED-VALUE. 32 DIVIDE W005-DIVISOR INTO W005-DIVIDEND GIVING W005-QUOTIENT 33 ON SIZE ERROR 34 DISPLAY "ON SIZE ERROR ENCOUNTERED" 35 DISPLAY "PROGRAM ABORTING" 36 STOP RUN. 37 DISPLAY "No On Size error". 38 DISPLAY "PROGRAM EXITING NORMALLY". 39 STOP RUN. --------------------------------------------------------- THE GO TO STATEMENT The GO TO statement verb provides an unconditional branch from the current set of statements to a specific section or paragraph in the program. Unlike the PERFORM verb, there is no return to where it came from and the execution will continue right at the section or paragraph specified as the operand of the verb. Many studies in structured programming have shown that the uncontrolled use of this verb can make the program logic hard to follow because of the many "jumps" that occur. I therefore suggest that we only use this verb in certain conditions. Fig. 4.24 shows an example of the GO TO. PAGE 33 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 PROGRAM LISTING 4.24 -------------------- PROG424 COB 14:37:39 02-Sep-90 PAGE 1 Line Number Source Line ANSI 74-85 Standard Cobol V.6.0 (c)1990. 1 IDENTIFICATION DIVISION. 2 * 3 PROGRAM-ID. CHAP424. 4 * 5 ENVIRONMENT DIVISION. 6 * 7 CONFIGURATION SECTION. 8 * 9 SPECIAL-NAMES. 10 PRINTER IS PRINTER-DISPLAY. 11 * 12 * 13 DATA DIVISION. 14 * 15 WORKING-STORAGE SECTION. 16 * 17 01 W005-DIVISOR PIC 9 VALUE 0. 18 * 19 01 W005-DIVIDEND PIC 99 VALUE 5. 20 * 21 01 W005-QUOTIENT PIC 9. 22 * 23 * 24 PROCEDURE DIVISION. 25 * 26 MAIN-LINE-LOGIC. 27 GO TO PRINT-COMPUTED-VALUE. 28 * 29 * 30 PRINT-COMPUTED-VALUE. 31 DIVIDE W005-DIVISOR INTO W005-DIVIDEND GIVING W005-QUOTIENT 32 ON SIZE ERROR 33 DISPLAY "ON SIZE ERROR ENCOUNTERED" 34 DISPLAY "PROGRAM ABORTING" 35 STOP RUN. 36 DISPLAY "No On Size error". 37 DISPLAY "PROGRAM EXITING NORMALLY". 38 STOP RUN. PAGE 34 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 THE COMPUTE STATEMENT The COMPUTE statement is used to evaluate an arithmetic expression. It can therefore be used in place of individual ADD, SUBTRACT, MULTIPLY, or DIVIDE statements. It is also used ijn exponentialtion (raising a number to a power), although VERSION 6.50 only allows integers for the exponent. It's main drawback is that the intermediate results are manipulated by the statement (not the programmer) and may result in truncation of digits to the right of tthe decimal point. Therefore, be careful when using this statement. An example of the use of COMPUTE is fig.4.26. PROGRAM LISTING 4.26 -------------------- PROG426 COB 14:41:15 02-Sep-90 PAGE 1 Line Number Source Line ANSI 74-85 Standard Cobol V.6.0 (c)1990. 1 * 2 IDENTIFICATION DIVISION. 3 * 4 PROGRAM-ID. CHAP426. 5 * 6 ENVIRONMENT DIVISION. 7 * 8 CONFIGURATION SECTION. 9 * 10 SPECIAL-NAMES. 11 PRINTER IS PRINTER-DISPLAY. 12 * 13 * 14 DATA DIVISION. 15 * 16 WORKING-STORAGE SECTION. 17 * 18 * 19 01 W005-GROSS-PAY PIC 9(4)V99. 20 * 21 01 W005-BASE-PAY PIC 999V99 VALUE 500. 22 * 23 01 W005-WEEK-HOURS PIC 99V99 VALUE 39.5. 24 * 25 * 26 PROCEDURE DIVISION. 27 * 28 MAIN-LINE-LOGIC. 29 GO TO PRINT-COMPUTED-VALUE. 30 * 31 * 32 PRINT-COMPUTED-VALUE. 33 COMPUTE W005-GROSS-PAY ROUNDED = 34 W005-BASE-PAY * ( 1 + 1.5 * ( W005-WEEK-HOURS - 35 ) / 35 ) 35 DISPLAY W005-GROSS-PAY. PAGE 35 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 36 COMPUTE W005-GROSS-PAY ROUNDED = 37 W005-BASE-PAY * ( 1 + ( 1.5 / 35 ) 38 * ( W005-WEEK-HOURS - 35)). 39 DISPLAY W005-GROSS-PAY. 40 STOP RUN. PAGE 36 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 CHAPTER 5 BASIC FILE OPERATIONS INTRODUCTION Cobol was deveeloped for business applications and as such was designed to make it easier ( compared to other language ) for programmers to write programs for applications like PAYROLL, INVENTORY CONTROL, ACCOUNTS REC. ECT. While its arithmetic capablities, though more than adequate for business applications, are not as extensive as those of fortran, its ablitity to process large amounts of data of different formats from different locations make it the most popular programming language for commercial applications. PAGE 37 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 FILES Data used in COBOL programs (except for low-volume data like an end-of-cycle date entered at the begining of the computer run) are generally contained in files. We may think of files as similar to file cabinets that contain a lot of information about a particular subject matter. In a payrole application, the PAYROLE MASTER FILE is one that contains information for all employees in the company. In an Inventory application, the INVENTORY MASTER FILE contains the relevant information about all items being stocked by the company. FILE ORGANIZATION Files used by ANSI-STANDARD COBOL 6.50 may fall under four types of organization. The regular sequential (usually called sequential) organization file is the type normally created by COBOL programs. The records are only logically sequential because the will appear that way to the program. They may not really be physically in sequence since DOS uses the first available sector on the disk on file operations. However, thisdoes not concern the programmer in cobol because DOS will retrieve these records in the proper sequence. The records in the file are of variable length and each one has a 2-byte prefix created by DOS containing the record number. This prefix is transparent to COBOL and is therefore not defined as part of the record. The line sequentional organization file has each record followed by a CR/LF. This type file is created normally by a word proc. The indexed organization and relative organization will be discussed in greater detail later on in the text. RECORDS Each record in the file may have up to 4,095 bytes but no more. PAGE 38 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 THE OPEN STATEMENT Each file used must be opened before any activity is allowed on it; else an error occurs. Any sequential READ statement will then retrieve the first record in the file. The format of the OPEN statement is: OPEN INPUT|OUTPUT|I-O|EXTEND FDFILENAME The following rules apply: 1. Filename corresponds to those in the SELECT and FD (file description) entries. 2. Files that are simultaneously opend as either INPUT,OUTPUT,I-O, or EXTEND may be grouped together. 3. INPUT,OUTPUT,I-O, and EXTEND may be coded in the same statement. 4. Use INPUT if the file already exists and will be used only for "READING" data from it. 5. Use OUTPUT if the file does not exist or you want to replace an existing file with new records generated in the program. The printer is ALWAYS an output file. 6. Use I-O if you want to add new records (WRITE), or update old records (REWRITE after a READ) to an existing disk file. NOTE: the file must already exist if the I-O mode is used. Also, the WRITE verb cannot be used in I-O mode if organization is sequential. 7. Use EXTEND if you want to append new records at the end of an existing file. NOTE: The file must already exist if tthe EXTEND mode is used. Only WRITE statements are allowed and only sequential files may be opened in EXTEND mode. THE CLOSE STATEMENT Each file used must be closed if no longer required, as for instance when all records have been read from or written to it. Closing files allows the operating system to do its housekeeping chores on the file, disposing of them properly depending on their nature. The format of the CLOSE statement is : CLOSE FDFILENAME WITH LOCK. You may thus close as many files you want in a single statement. The WITH LOCK option makes sure that the file cannot be reopened in the same program. If required, it is coded for the specific files that require them. PAGE 39 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 THE READ STATEMENT The read statement brings an existing record into your program. It can only be used for files that are opened as INPUT or I-O. The format is: READ FDFILENAME INTO DATA-NAME AT END, statements The INTO option specifies a data name in the WORKING- STORAGE section that will receive the data. The AT END condition specifies the imperative statements that will be executed when that are no more records in the file. THE WRITE STATEMENT (PRINT FILE) The WRITE statement writes records into an output file. Here, we will only discuss it's use in generating print lines on the printer. This is used to prepare well- structured reports of the type used by management and employee personal, unlike the DISPLAY verb, which is basically used to print unstructured, short messages for the computer operator. Extreme care must be made when using both features since we don't want messages mixed in with reports. The format for the WRITE statement is: WRITE print-record AFTER ADVANCING data-name|literal LINES|PAGE Print-record is th 01-level record defined as part of the FD entry for the file. The "AFTER ADVANCING" clause specifies the printer carrage control skipping action before the line is printed. The "AFTER ADVANCING PAGE" option specifies that the line is printed after the paper is positioned on a new page. The "AFTER ADVANCING data-name|literal LINES" option specifies that the paper is advanced so many lines before the line is printed. The literal must be an unsigned integer and the data- name defined as an unsigned integer, and skipping will occur according to the following values they hold: VALUE CARRIAGE CONTROL ACTION -------------------------------------------------------- 0 NO SPACING 1 NORMAL (PRINT ON NEXT LINE) 2 1 BLANK SPACE BEFORE PRINTING 3 2 BLANK SPACES BEFORE PRINTING . .... . .... 120 119 BLANK SPACES BEFORE PRINTING PAGE 40 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 PROGRAM LISTING 5.01 -------------------- PROG501 COB 15:25:03 02-Sep-90 PAGE 1 Line Number Source Line ANSI 74-85 Standard Cobol V.6.0 (c)1990. 1 IDENTIFICATION DIVISION. 2 * 3 PROGRAM-ID. PROG501. 4 * 5 DATE-WRITTEN. 08/13/90. 6 * 7 AUTHOR. BOB NOWECK. 8 * 9 SECURITY. NONE. 10 * 11 * 12 ENVIRONMENT DIVISION. 13 * 14 INPUT-OUTPUT SECTION. 15 * 16 FILE-CONTROL. 17 * 18 SELECT EMPLOYEE-ADDRESS-MASTER 19 ASSIGN TO DISK 20 ORGANIZATION IS LINE SEQUENTIAL. 21 * 22 SELECT EMPLOYEE-ADDRESS-PRINT 23 ASSIGN TO PRINTER. 24 * 25 * 26 DATA DIVISION. 27 * 28 FILE SECTION. 29 * 30 FD EMPLOYEE-ADDRESS-MASTER 31 LABEL RECORDS STANDARD 32 VALUE OF FILE-ID IS "FIOPRT.DAT". 33 01 EMPLOYEE-ADDRESS-MASTER-RECORD. 34 05 EMPLOYEE-ADDRESS-MASTER-NAME PIC X(30). 35 05 EMPLOYEE-ADDRESS-MASTER-STREET PIC X(30). 36 05 EMPLOYEE-ADDRESS-MASTER-CITY PIC X(30). 37 * 38 FD EMPLOYEE-ADDRESS-PRINT 39 LABEL RECORDS OMITTED. 40 01 EMPLOYEE-ADDRESS-PRINT-LINE PIC X(30). 41 * 42 * 43 WORKING-STORAGE SECTION. 44 * 45 01 W005-END-OF-FILE-SWITCH PIC X. 46 88 W005-END-OF-FILE VALUE "1". 47 01 W005-LINE-SKIP PIC 99. 48 * 49 PROCEDURE DIVISION. 50 * PAGE 41 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 51 C000-MAIN-LINE-LOGIC. 52 * 53 OPEN INPUT EMPLOYEE-ADDRESS-MASTER 54 OUTPUT EMPLOYEE-ADDRESS-PRINT. 55 MOVE "0" TO W005-END-OF-FILE-SWITCH. PROG501 COB 15:25:03 02-Sep-90 PAGE 2 Line Number Source Line ANSI 74-85 Standard Cobol V.6.0 (c)1990. 56 PERFORM C060-READ-EMPLOYEE-MASTER. 57 PERFORM C020-PROCESS-EMPLOYEE-MASTER 58 UNTIL W005-END-OF-FILE. 59 CLOSE EMPLOYEE-ADDRESS-MASTER 60 EMPLOYEE-ADDRESS-PRINT. 61 STOP RUN. 62 * 63 C020-PROCESS-EMPLOYEE-MASTER. 64 * 65 MOVE EMPLOYEE-ADDRESS-MASTER-NAME 66 TO EMPLOYEE-ADDRESS-PRINT-LINE. 67 MOVE 3 TO W005-LINE-SKIP. 68 PERFORM C040-WRITE-DETAIL-LINE. 69 MOVE EMPLOYEE-ADDRESS-MASTER-STREET 70 TO EMPLOYEE-ADDRESS-PRINT-LINE. 71 MOVE 3 TO W005-LINE-SKIP. 72 PERFORM C040-WRITE-DETAIL-LINE. 73 MOVE EMPLOYEE-ADDRESS-MASTER-CITY 74 TO EMPLOYEE-ADDRESS-PRINT-LINE. 75 MOVE 3 TO W005-LINE-SKIP. 76 PERFORM C040-WRITE-DETAIL-LINE. 77 PERFORM C060-READ-EMPLOYEE-MASTER. 78 * 79 C040-WRITE-DETAIL-LINE. 80 * 81 WRITE EMPLOYEE-ADDRESS-PRINT-LINE 82 AFTER ADVANCING W005-LINE-SKIP LINES. 83 * 84 C060-READ-EMPLOYEE-MASTER. 85 * 86 READ EMPLOYEE-ADDRESS-MASTER 87 AT END, MOVE "1" TO W005-END-OF-FILE-SWITCH. PAGE 42 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 CODING THE IDENTIFICATION AND ENVIRONMENT DIVISIONS INTRODUCTION In the past chapters, we have discussed enough basic features of COBOL for the reader to code simple programs. In the previous chapter, we mentioned the concept of "structured programming" to write programs that are easy to read and therefore maintain. From now on, we will broaden this concept to include specific techniques that are useful in the four COBOL divisions. This extends the concept beyond the original idea of structured programming, which was mainly for easy-to- read code in the PROCEDURE DIVISION. PAGE 43 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 THE IDENTIFICATION DIVISION This division identifies the program, and as options may identify it author, it's purpose, and other characteristics like when it was written, ect. Besides the division header "IDENTIFICATION DIVISION." which is coded starting in column 8, there is only one other required entry for the division and this is the "PROGRAM-ID." entry which is also coded starting in column 8. The operand must be 8 characters or less and start with an alphabetic character. The periods after "IDENTIFICATION DIVISION." are manditory, as well as the "PROGRAM-ID.". DATE-WRITTEN. SOURCE-COMPUTER. OBJECT-COMPUTER. AUTHOR. SECURITY. are not manditory but maybe added for arcival purposes. THE ENIVRONMENT DIVISION This division, which starts with the division header "ENVIRONMENT DIVISION." coded starting in column 8, contains the entries that relate your program to the physical characteristics of the hardware to be used. While COBOL is to a large extent machine-independent, this division is needed to specify things like file organization, device type, and others which are to some extent machine-dependent. CONFIGURATION SECTION This division contains two opional sections, "CONFIGURATION SECTION." and "INPUT-OUTPUT SECTION." which are coded in column 8 and must be in that order if both are present, There are 2 paragraphs in the "CONFIGURATION SECTION.". The "SOURCE-COMPUTER." paragraph is used in debugging and will be explained later on. The "SPECIAL-NAMES." paragraph has severial entries, one of which is the "PRINTER IS" entry which is coded in column 12 and is used with displaying of information on the printer. PAGE 44 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 INPUT-OUTPUT SECTION The "INPUT-OUTPUT SECTION." contains the "FILE-CONTROL." paragraph, which is coded in column 8, and which is required if the program uses files. There will be entries under this paragraph, one for each file used. Each entry is a SELECT statement that starts in column 12, and may be continued on the next line, and ends with a period. The format for the SELECT statement is: SELECT data-file-name ASSIGN TO DISK|PRINTER FILE STATUS IS data-name ACCESS MODE IS SEQUENTIAL|RANDOM|DYNAMIC ORGANIZATION IS SEQUENTIAL|LINE SEQUENTIAL|RELATIVE|INDEXED RECORD KEY IS data-name-2 RELATIVE KEY IS data-name-3 The following rules apply: 1. Use filenames that are self-documenting. In the example I use EMPLOYEE-ADDRESS-MASTER and EMPLOYEE- ADDRESS-PRINT as file names. 2. Use DISK if it is a disk file and PRINTER if it is the printer. 3. The FILE STATUS clause is used for disk files with relative or indexed file organization, data-name is a two-character data item that contains the value set after every I-O statement. The returned values are: FILE STATUS value MEANING ______________________________________________ 00 SUCCESSFUL COMPLETION 10 END OF FILE 21 KEY NOT IN SEQUENCE(INDEXED) 22 DUPLICATE KEY ON WRITE 23 NO RECORD FOUND 24 DISK FULL 30 HARDWARE ERROR (DISK NOT READY ECT.) 91 FILE STRUCTURED DESTROYED PAGE 45 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 CHAPTER 7 CODING THE DATA DIVISION Introduction The data division is where data used in the program except for literals used in statements are defined. The data maybe coming from a file will be written to a file or used in intermediate processing. It is important that certain techniques be used so that the data names can be easily located and read from the program listing and thus facilitate program debugging. It is also important that we select the proper data format so as to help make the program more efficient. PAGE 46 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 Sections This division starts with the division header "DATA DIVISION" that is coded starting in column 8. There are 4 optional sections that maybe defined all of which start with a section header that is coded starting in column 8. These sections are "FILE SECTION", "WORKING-STORAGE SECTION", "LINKAGE SECTION", "SCREEN SECTION" and must appear in that order if defined. FILE SECTION This section starts with header "FILE SECTION" and contains one entry for each file defined in the select statement in the file control paragraph of the ENVIRONMENT DIVISION. The file description entry has the following format. FD file name LABEL RECORD | RECORDS IS | ARE OMITTED | STANDARD VALUE OF FILE ID IS data name. The following rules apply: 1) the 2 clauses LABEL RECORDS AND VALUE OF can be in any order. 2) the FD "file description" literal is coded in column 8, but file name in clauses are coded starting in column 12. 3) all file names defined by select statements must have a corresponding FD entry and the spelling of the file name is naturally identical for both entries. 4) the LABEL RECORDS must be specified as standard for disc files and omitted for printer. 5) the value of file ID clause must be specified for disc files and omitted for printer. It is used by DOS for locating the file during the computer run and is therefore defined according to the rules for file names for DOSS. It has the format DRIVE:FILE NAME.EXTENSION. FILE RECORD ENTRIES The format for records in each file is coded right after the corresponding FD entry. Each record is defined with an O1 Level with the level number starting in column 8. The data name itself starts in column 12. This record maybe further subdivided into lower level data items or fields. PAGE 47 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 Data Item Definition The data items coded in various sections of this division except for those of screen formatting use similar formats. The format is: level # data-name REDEFINES data name. level # data-name PICTURE | PIC IS picture type OCCURS integer TIMES INDEX BY index-name USAGE IS usage-type VALUE IS literal. The following rules apply: 1) The level # is 01 if we are defining a record. A record here means that either a file record entry at the file section, a group of data names at the working storage section or the linkage section or the format of the whole screen in the screen section. 2) The level # for entries under the 01 range from 02- 49. However it is best to use numbered steps like 05,10,15, etc. so any further changes later on maybe easily made by using numbers in between. 3) The level number for a condition name entry is 88. This entry can only have a data name in the value clause. 4) I suggest that you do not use level 77 which are independent from other data items. It is better to code data names which are used together as groups so they are easily seen together in the program listing. This is also used full when you write COBOL for mainframes because of paging problems in virtual storage systems. 5) Data name should be defined so that the reader immediately notices what the data represents just from it's name. An example is EMPLOYEE-ADDRESS- MASTER. 6) The redefines clause specifies that the area occupied by data-name-2 will also contain data-name-1. It is often used to provide alternate grouping or description of the same data item. If coded it should be the first clause following data-name-1 and data-name-2 is a data item coded just ahead of it. 7) Pic or picture specifies the format of the data item and should be coded only for elementary data items. The different picture types are the following: a) Alphanumeric. This applies to a data item which may contain alphabet and numeric characters and therefore not used in arithmetic operations. Picture type is specified with Xs. A number enclosed in parenthesis means a repeat of one occurence of an X. For instance, picXXXXX is identical to picX[5]. b) Numeric. This field contains only numbers and is usefful for fields in arithmetic operations. This is defined with an S. If there is a sign 9 is PAGE 48 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 used for digits and V for the assumed position of the decimal point. This data item has the usage display oprand as a default or must have the comp- 0 "binary" or comp-3 "packed decimal" specified. c) Editing. This field is used for editing numeric fields in preparation for printing them the reports. d) Try to code pic or picture somewhere in column 44 or 48 or even further to a line off picture specification for easy reading. You will generally have enough space on the left for the data items and on the right for the other clauses. e) In this section, file section, the value clause is only used for condition names and not data names. f) Code line seperators as in other divisions. ------------------------------------------------------------------------------- WORKING STORAGE SECTION This section contains data that are mainly used for intermediate processing such as counters, tables, etc. This data are generally not directly related to records and files. The file record entries under FDs except where we use the into option of verb or from option of the write or rewrite verbs. Coding techniques for this section is basically identical to those of the file section except the following: 1) The 01 level group item does not correspond to any record and therefore the programmer may group data items under it in any way he chooses. He should, however, try to group data together that are related. 2) The value clause maybe used in this section. LINKAGE SECTION This section is used if the program is being called by another program. It will contain description of data items that the called program needs and has the correspondence to certain data items defined in the working storage section of the calling program. This section will actually not have memory allocated for it, but will just use the memory allocated to the corresponding files in the calling program. Just like the data items in the file section the value clause maybe specified only for condition names. SCREEN SECTION This section defines format of the screen to be used in the program for displaying formatted data. Display or exhibit verbs or accepting formatted data except verbs. PAGE 49 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 CODING THE PROCEDURE DIVISION Introduction This division contains specific instructions that the programmer wants executed and thus carries logic of the program. It is the division that can benefit most from good programming techniques and it contributes most to the rehability and efficiency of the program. PAGE 50 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 Structure Programming This is a technique that grew out of research begun in the academic community some 30 or 40 years ago. It's main aim was to make programs easier to read and thus understand by having the programmer code them in a certain style. One of it's main ideas is to avoid any GO TO statements since they made the larger quota to follow. The unconditional branch caused by each GO TO disrupts the normal flow of control from a statement to the one following it. Some proponents of structure programmings have expand and redefined this idea to include many other techniques. They have not eliminated GO TOs all together, but just restrict their use to certain conditions. Program Constructs Structured programming requires statements follow the rule of one entry and one exit. Constructs which consists of one or more statements must acquire control starting execution at only one point in a relinquished control stop execution at only one point. Reading the program listing is thus made easier since we know that a construct will eventually exit at one point. Any branch outside of the construct will only be temporary done through performed verbs. From this we can conclude that GO TOs are to be avoided. GO TOs are supported although in version 6.50. Examples of this are MOVE, DISPLAY, EXHIBIT, etc. Statements which we simply execute before proceeding in the next statement. Let's look at the following set of statements. MOVE "ERA 5" TO MESSAGE 005-MESSAGE-CODE. EXHIBIT NAMED W005-MESSAGE-CODE. DISPLAY "TEST 01 RUN ABORTED". You will note that each statement is simply executed and control flows right through to the next statement. The IF Condition We must understand that statements under the true or false boxes could be a combination of valid constructs. The important thing is always is to have one entry point and one exit thus nested IFs something that may seem tricky to use are very powerful to the structure programming. While confusing if done improperly they are easy to understand if properly indented. Note that the constructs start at the IF statement and ends with a period. No matter what values of W005-TRANS-HOURS and W01-HOURS-LIMIT are. Control will eventually reach the statement following the construct. Perform until constructs. The construct governed by the false condition the performed body will be executed repeatedly until condition becomes true. At which time the apparent original construct exists. When the constructs in the performed body must eventually set the condition true to enable use to exit from the apparent construct PAGE 51 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 otherwise we have it endlessly. Note that the paragraph C200-0-OUT-CELLS will be executed repeatedly until the value of W05CELLS I is greater than the value of total stores. The sentence statement will cause this to happen at some point in the construct exits. Modular Programming One of the developments in structure programming was the idea of modularizing the program by coding into it's sections. This idea is extensively used to COBOL programs written for mainframes where the use of advanced features like Sort require it. It is also useful and is used in COBOL 6.50. It is mandatory if the program is too large for computer memory requiring it to be segmented. Secondly you may some day want to write COBOl programs for mainframes or port the programs that you have already written over to mainframes and you would need to know how these sections are used. The Main Line Section The programs start to execute at the first verb of the PROCEDURE DIVISION excluding statements and the declarative section. It is therefore a good idea to control the program logic in this area. It is also the first part of the program a programmer would look at. The most common name for this section is C000-MAIN-LINE. C00 is a prefix which will be described later on. The first paragraph of this section as a minimum does the following: 1) Performs initialization section if any. This section will execute the initial routines like read and attail, accept the date used in processing, etc. 2) Open the files to be used in the section. 3) Perform the initial read of the input files. 4) Perform the paragraph that processes the input files until the end of file perform until. 5) Performs the finalization section if any. This section executes a final housekeeping routines like print control, etc. 6) Close files using the section. 7) Issues a stop run statement. Other Sections Sections invogued by the mainline section to the perform statements are coded in the following matter: 1) The first paragraph the section controls through the perform statement the processing of the whole section. It therefore does the following: a) opens all files to be processed in the section. b) performs initial read of the input files. PAGE 52 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 c) performs a paragraph that processes the files until all records have been processed. d) closes all files processed in thesection. e) exit section. Paragraphs Paragraphs that fall under the section are coded as they are needed. Each one should only do one function so as to keep it as simple and as easy to read as possible. If the paragraph you are currently coding does too many different functions than you should break it up into several paragraphs. Seperate all paragraphs from each other. In front of section headers, space and a line seperator between them. Prefixes for Procedure Names In much the same manner that the prefixes for data names make it easier to pinpoint their location in the program listing section and paragraph name should also have prefixes. This task just is to have the prefix consisting of a letter followed by 3 digit number followed by hyphen. You can easily use the letter C for the first section, F for the second, J for the third, etc. However you prefer to do it. And have enough letters in between for future modifications. The digits start with 000 for the section header and incremented by 20 for the paragraphs. This should give you enough numbers for the paragraphs in the section. Otherwise makes succeeding paragraphs have 4 digit numbers in the prefix. Self Documented Procedure Names Just like data names it is important that the procedures names be self documenting. You are allowed 30 characters for this procedure names and this is generally enough to allow the user to understand the function of the procedure from the name. A paragraph name like C200-COMPUTE-GLOSSARY-PAY is much better than C200-COMPUTE. PAGE 53 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 Statements and Sentences The logic in the PROCEDURE DIVISION is coded with statements each one being sentactically correct combination of words and symbols thus specifies an action to be done, ADD, MULTIPLY, MOVE, etc. or a condition to be tested, IF. One or more statements that terminates with a period is called a sentence. The following are suggested in coding statements and sentences: 1) there should only be one statement per line. 2) always start each sentence in column 12. 3) if the statement has to be continued in another line indent the continuation line relative to the start of the sentence. 4) if a statement is independent of other statements make it into a sentence ending it with a period. 5) If a statement has several optional clauses code them in succeeding lines instead of the same line so they standout better. They should also be indented relative to the start of the statement. 6) if you use IFs if subordinate to other IFs than aline the Ls to the corresponding IF for readability. PAGE 54 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 CHAPTER 9 Screen Processing Format Accept 3 Introduction One feature of personal computers is of any display unit which is extensively used to accept data entered by or displayed for the operator. Unlike typical COBOL programs written for mainframes where the datas are generally batched together by the data entry department unless a teleprocessing package like CICS is used the ANSI-STANDARD COBOL 6.50 allows use of format it's grades for easily input and output of information. Much like an online system the operator may enter data via the keyboard and this maybe immediately used by the program to add update retrieve for delete records and files. We will deal here with the screen processing based on the format 3 version of the accept verb. This allows the processing of individual fields as they are entered in the keyboard. Format 4 processing which is actually simpler to code will be discussed later on. PAGE 55 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 Screen Format We will deal only with the IBM Monochrome Display Unit which is 24 by 80 columns for information. While there is a total of 1980 characters that maybe entered the program generally uses only a portion of this capacity in applications. Screen Header or Title A typical screen used will have 3 areas defined. The top one are 2 lines will be the header or title and has literal value that will be indicated to the operator what he or she is using. Typically headers would be "ACCOUNTS RECEIVABLE ENTRY or PAYROLL ENTRY", something to tell the operator what he is looking at. The header must naturally be self defining and is usually defined with the highlight oprand so it can be easily read. Application Data Area The main portion of the screen is where the application data which contains the information entered by the operator which comes from files. This consists of 2 types of data. One is field identifiers which are used to identify the fields on the screen. This has literal value that will indicate to the operator what he or she is looking at. The field identifier is generally coded just above the data it defines or to it's left in which case it generally ends with a semicolon. Some typical field identifiers have values like "NAME:" to identify the name field, "DEPT:" for a department number. This field is generally specified with the HIGHLIGHT operand so it can be easily seen on the screen. The data itself is the information that is important to the operator and is usually defined with the REVERSE-VIDEO operand so it is easily differentiated from its field identifier. Some programmers may prefer to define this with the HIGHLIGHT operand instead of the REVERSE-VIDEO operand. In this case, make sure that the identifier does no have the HIGHLIGHT operand so the two can be differentiated. THE OPERATOR MESSAGE AREA The operator message area is generally coded at the bottom of the screen and contains the literal that is displayed for the operator. If this message corresponds to an error, the programmer should define the field with both the HIGHLIGHT and BLINK operands so it is easily seen by the operator. If this message guides the operator, then it should be defined with either REVERSE- VIDEO (prefered) or HIGHLIGHT operand. PAGE 56 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 THE SCREEN SECTION. While the programmer is able to display or accept information on the screen without formatting, this has limited capabilities because only the formatted screen as defined in the SCREEN SECTION of the DATA DIVISION will allow the programmer to use aids such as HIGHLIGHT, REVERSE-VIDEO, FOREGROUND-COLOR, ect. This is almost mandatory for typical applications since they require the entry of several different types of data where a formatted screen is needed. The following is 'suggested' rules for coding the SCREEN SECTION: 1). The whole screen corresponds to a 01-level screen-name. 2). The fields on the screen are defined with level 02 to 49 just like those in the WORKING-STORAGE SECTION. 3). Each elementary item is defined as follows: a. The level number is specified in the same manner as in the WORKING-STORAGE SECTION. b. Screen-name is defined if we use the group or elementary item in ACCEPT and DISPLAY statements in the PROCEDURE DIVISION. Therefore, data fields and operator messages have their corresponding screen-names. Headers and field identifiers do not normally need screen-names. c. BLANK SCREEN. Is always coded by itself as the first entry after the 01-level entry. This erases the previous screen before a new screen is displayed. d. All elementary items must have the LINE NUMBER and COLUMN NUMBER operands. This specifies the exact location on the screen that the data-item will start. e. The REVERSE-VIDEO operand is used for data fields, and is the logical choice for non- error initiated operator messages. f. The HIGHLIGHT opernad is used for the screen headers. It is the logical choice for field identifiers if the data fields are defined with the REVERSE-VIDEO operand. It is also the second choice for operator messages that are not error-initiated. The HIGHLIGHT and BLINK operands together is the logical choice for operator messages that are displayed on errors. g. The BLINK operand, as noted before, is used in conjunction with the HIGHLIGHT operand for error-initiated operator messages. i. The FOREGROUND-COLOR operand sets the foreground color, it should be coded on a line by itself. It must have an integer or integer constant to specify the color choice. 0 - BLACK PAGE 57 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 1 - LOW-LEVEL BLUE 2 - LOW-LEVEL GREEN 3 - LOW-LEVEL LIGHT BLUE 4 - LOW-LEVEL RED 5 - LOW-LEVEL MAGENTA 6 - LOW-LEVEL BROWN 7 - LOW-LEVEL WHITE 8 - LOW-LEVEL GRAY 9 - HIGH-LEVEL BLUE 10 - HIGH-LEVEL GREEN 11 - HIGH-LEVEL LIGHT BLUE 12 - HIGH-LEVEL RED 13 - HIGH-LEVEL MAGENTA 14 - HIGH-LEVEL YELLOW 15 - HIGH-LEVEL WHITE j. The BACKGROUND-COLOR operand is coded as the FOREGROUND-COLOR operand with the exception of only the 0 - 9 colors. k. The "VALUE IS literal" operand is used for headers and field identifiers or any field that must contain an initial value when the screen is displayed. Data fields generally do not have this operand because the data will be what is entered by the operator. l. The "PIC IS picture string" operand is used for data fields, the "FROM", "TO", and "USING" operands in certain combinations. m. For most applications, the "USING identifier" is the most useful. This means that the data item will receive the data entered be the operator via the ACCEPT verb and will also be the source of the data on the DISPLAY verb. n. The "FROM indentifier" operand will contain data to be displayed on the screen through a MOVE instruction. This operand functions only in the DISPLAY mode. o. The "TO indentifier" operand is used for data entry fields. This operand functions only with the ACCEPT verb. THE DISPLAY VERB In chapters 3 and 4, I explained the use of the DISPLAY verb. I will now give a more detailed explanation, especially on the aspect of the verb that displays data on the formatted screens. the format is: DISPLAY screen-name Screen-name is the same as that defined in the SCREEN SECTION. The location on the display where the data items will show is defined in the LINE and COLUMN operands of that item. If you wish you can write to the screen location by using the DISPLAY verb. The format is: PAGE 58 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 DISPLAY ( ROW, COLUMN ) THE ACCEPT FORMAT 3 The format 3 version is: ACCEPT ( position-spec ) identifier WITH AUTO-SKIP The following rules apply: 1). Position-spec has the same value as in the DISPLAY verb. 2). Identifier is the field that will receive data. 3). The "WITH AUTO-SKIP" is useful for fixed-length input fields. The input will automatically end without the operator having to press the enter key, when the length is reached, as defined by the PIC operand. 4). The ACCEPT ends, which means we go to the next following statement, if: a. A terminator key is hit. These are ENTER, TAB, BACK-TAB(shift + tab), ESCAPE, and the Function Keys. b. AUTO-SKIP is specified and the operator entered a character in the low-order(rightmost) data input position. PROGRAM LISTING 9.01 -------------------- PROG901 COB 13:38:54 03-Sep-90 PAGE 1 Line Number Source Line ANSI 74-85 Standard Cobol V.6.50(c)1990. 1 IDENTIFICATION DIVISION. 2 * 3 PROGRAM-ID. PROG901. 4 * * 5 *************************************************************** 6 * * 7 * 1. DATE-WRITTEN. 08/03/90. * 8 * * 9 * 2. THIS PROGRAM ACCEPTS ENTRIES FROM THE CONSOLE DISPLAY * 10 * AND DISPLAYS THEM ON THE PRINTER. THE FIELDS ARE: * 11 * A) FIELD 1 - NAME * 12 * B) FIELD 2 - ADDRESS * 13 * C) FIELD 3 - CITY/STATE * 14 * * 15 *************************************************************** 16 * 17 * 18 ENVIRONMENT DIVISION. 19 * 20 CONFIGURATION SECTION. 21 * 22 SPECIAL-NAMES. 23 * PAGE 59 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 24 PRINTER IS PRINTER-DISPLAY. 25 * 26 * 27 DATA DIVISION. 28 * 29 *************************************************************** 30 * * 31 WORKING-STORAGE SECTION. 32 * * 33 *************************************************************** 34 * 35 * USES OF W005-KEYBOARD-KEY-SWITCH 36 * ] . F9 KEY -- END OF JOB. 37 * 38 01 W005-KEYBOARD-KEY-SWITCH PIC 99. 39 88 W005-F9-KEY-ACTIVATED VALUE 10. 40 * 41 01 W005-RECORD-ACCEPTED-COUNT PIC 9(4) VALUE +0. 42 * 43 01 W010-EMPLOYEE-WK-RECORD. 44 05 W010-EMPLOYEE-WK-NAME PIC X(30). 45 05 W010-EMPLOYEE-WK-STREET PIC X(25). 46 05 W010-EMPLOYEE-WK-CITY PIC X(25). PROG901 COB 13:38:54 03-Sep-90 PAGE 2 Line Number Source Line ANSI 74-85 Standard Cobol V.6.50(c)1990. 47 / 48 *************************************************************** 49 * * 50 SCREEN SECTION. 51 * * 52 *************************************************************** 53 * 54 * 55 01 SCREEN1-ADDRESS-ENTRY. 56 05 BLANK SCREEN. 57 05 LINE 1 COLUMN 16 VALUE "E M P L O Y E E" 58 HIGHLIGHT. 59 05 LINE 1 COLUMN 35 VALUE "A D D R E S S" 60 HIGHLIGHT. 61 05 LINE 1 COLUMN 52 VALUE "E N T R Y" 62 HIGHLIGHT. 63 05 LINE 3 COLUMN 24 HIGHLIGHT 64 VALUE "NAME:". 65 05 SCREEN1-NAME LINE 3 COLUMN 30 66 PIC X(30) 67 REVERSE-VIDEO 68 USING W010-EMPLOYEE-WK-NAME. 69 05 LINE 5 COLUMN 22 HIGHLIGHT 70 VALUE "STREET:". 71 05 SCREEN1-STREET LINE 5 COLUMN 30 72 PIC X(25) 73 REVERSE-VIDEO 74 USING W010-EMPLOYEE-WK-STREET. 75 05 LINE 7 COLUMN 18 HIGHLIGHT PAGE 60 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 76 VALUE "CITY/STATE:". 77 05 SCREEN1-CITY LINE 7 COLUMN 30 78 PIC X(25) 79 REVERSE-VIDEO 80 USING W010-EMPLOYEE-WK-CITY. PROG901 COB 13:38:54 03-Sep-90 PAGE 3 Line Number Source Line ANSI 74-85 Standard Cobol V.6.50(c)1990. 81 / 82 PROCEDURE DIVISION. 83 * 84 *************************************************************** 85 * * 86 C000-MAIN-LINE SECTION. 87 * * 88 *************************************************************** 89 * 90 C020-MAIN-LINE-LOGIC. 91 MOVE 98 TO W005-KEYBOARD-KEY-SWITCH. 92 PERFORM C120-DISPLAY-NEW-SCREEN. 93 PERFORM C040-PROCESS-NAME-ENTRY 94 THRU C100-PROCESS-SCREEN-EXIT 95 UNTIL W005-F9-KEY-ACTIVATED. 96 PERFORM C980-EOJ-ROUTINE. 97 STOP RUN. 98 * 99 C040-PROCESS-NAME-ENTRY. 100 ACCEPT ( 3, 30 ) 101 W010-EMPLOYEE-WK-NAME. 102 ACCEPT W005-KEYBOARD-KEY-SWITCH FROM ESCAPE KEY. 103 IF W005-F9-KEY-ACTIVATED 104 GO TO C100-PROCESS-SCREEN-EXIT. 105 * 106 C060-PROCESS-STREET-ENTRY. 107 ACCEPT ( 5, 30 ) 108 W010-EMPLOYEE-WK-STREET. 109 ACCEPT W005-KEYBOARD-KEY-SWITCH FROM ESCAPE KEY. 110 IF W005-F9-KEY-ACTIVATED 111 GO TO C100-PROCESS-SCREEN-EXIT. 112 * 113 C080-PROCESS-CITY-ENTRY. 114 ACCEPT ( 7, 30 ) 115 W010-EMPLOYEE-WK-CITY. 116 ACCEPT W005-KEYBOARD-KEY-SWITCH FROM ESCAPE KEY. 117 IF W005-F9-KEY-ACTIVATED 118 GO TO C100-PROCESS-SCREEN-EXIT. 119 EXHIBIT NAMED W010-EMPLOYEE-WK-NAME UPON PRINTER-DISPLAY. 120 EXHIBIT NAMED W010-EMPLOYEE-WK-STREET UPON PRINTER-DISPLAY. 121 EXHIBIT NAMED W010-EMPLOYEE-WK-CITY UPON PRINTER-DISPLAY. 122 ADD 1 TO W005-RECORD-ACCEPTED-COUNT. 123 PERFORM C120-DISPLAY-NEW-SCREEN. 124 C100-PROCESS-SCREEN-EXIT. EXIT. 125 * 126 C120-DISPLAY-NEW-SCREEN. 127 MOVE SPACES TO W010-EMPLOYEE-WK-NAME PAGE 61 ANSI-COBOL 6.50 USERS MANUAL COPYWRITE 1990 128 W010-EMPLOYEE-WK-STREET 129 W010-EMPLOYEE-WK-CITY. 130 DISPLAY SCREEN1-ADDRESS-ENTRY. PROG901 COB 13:38:54 03-Sep-90 PAGE 4 Line Number Source Line ANSI 74-85 Standard Cobol V.6.50(c)1990. 131 / 132 C980-EOJ-ROUTINE. 133 IF W005-RECORD-ACCEPTED-COUNT GREATER THAN ZEROS 134 DISPLAY "JOB PROG901: SUCCESSFUL ENTRY COMPLETED" 135 UPON PRINTER-DISPLAY 136 ELSE DISPLAY "JOB PROG901: UNSUCCESSFUL ENTRY" 137 UPON PRINTER-DISPLAY. 138 EXHIBIT NAMED W005-RECORD-ACCEPTED-COUNT 139 UPON PRINTER-DISPLAY. PAGE 62