B. COBOL CHARACTER SET AND RESERVED WORDS
by Robert A. Stern, Nancy Stern, James Cooper
PROGRAMMING IN COBOL/400: 2nd Edition
- Copyright
- ACKNOWLEDGMENTS
- PREFACE
- 1. PHYSICAL FILES
- 1.1. CHAPTER OBJECTIVES
- 1.2. HIERARCHY OF DATA
- 1.3. INTERNAL BINARY REPRESENTATION OF DATA
- 1.4. DATA TYPES
- 1.5. ALPHANUMERIC (CHARACTER) FIELDS
- 1.6. NUMERIC FIELDS
- 1.7. ZONED DECIMAL FORMAT
- 1.8. PACKED DECIMAL FORMAT
- 1.9. PACKING NUMERIC DATA
- 1.10. CONVERTING ZONED DECIMAL FORMAT TO PACKED DECIMAL FORMAT
- 1.11. CONVERTING PACKED DECIMAL FORMAT TO ZONED DECIMAL FORMAT
- 1.12. DATE FORMAT
- 1.13. DATA FILES
- 1.14. ACCESS PATHS
- 1.15. HOW DATA ARE ORGANIZED AND RETRIEVED IN AN ARRIVAL SEQUENCE (NONKEYED) PHYSICAL FILE
- 1.16. HOW DATA ARE ORGANIZED AND RETRIEVED IN A KEYED SEQUENCE PHYSICAL FILE
- 1.17. CREATING A PHYSICAL FILE
- 1.18. CASE PROBLEM: CREATING A PHYSICAL FILE
- 1.19. DETERMINE THE RECORD FORMAT FOR THE PHYSICAL FILE
- 1.20. DATA DESCRIPTION SPECIFICATIONS (DDS) FOR AN ARRIVAL SEQUENCE FILE
- 1.21. DDS FOR A KEYED SEQUENCE FILE
- 1.22. COMPILE SOURCE DDS INTO A FILE OBJECT
- 1.23. DISPLAYING THE FIELD ATTRIBUTES OF A PHYSICAL FILE
- 1.24. ENTERING DATA INTO A PHYSICAL FILE WITH DFU
- 1.25. DISPLAYING THE CONTENTS OF PHYSICAL FILE RECORDS
- 1.26. PRINTING OR DISPLAYING RECORDS WITH THE COPY FILE (CPYF) COMMAND
- 1.27. USING THE CHANGE PHYSICAL FILE (CHGPF) COMMAND
- 1.28. END-OF-CHAPTER AIDS
- 1.29. CHAPTER SELF-TEST
- 1.30. CHAPTER REVIEW QUESTIONS
- 2. AN INTRODUCTION TO PROGRAMMING IN COBOL/400
- 2.1. CHAPTER OBJECTIVES
- 2.2. TYPES OF COMPUTER PROGRAMS
- 2.3. OPERATING SYSTEM SOFTWARE
- 2.4. APPLICATION PROGRAMS
- 2.5. MACHINE LANGUAGE PROGRAMS
- 2.6. SYMBOLIC PROGRAMS
- 2.7. AN INTRODUCTION TO COBOL
- 2.8. COBOL IS A STANDARD LANGUAGE
- 2.9. COBOL IS AN ENGLISH-LIKE LANGUAGE
- 2.10. COBOL IS A USER-FRIENDLY LANGUAGE
- 2.11. A HISTORY OF COBOL AND THE ANS VERSIONS
- 2.12. THE AMERICAN NATIONAL STANDARDS (ANS) VERSIONS OF COBOL
- 2.13. ILE COBOL AND THE ANS COBOL 1985 STANDARD
- 2.14. THE APPLICATIONS PROGRAM DEVELOPMENT PROCESS
- 2.15. DETERMINE THE PROGRAM SPECIFICATIONS
- 2.16. DESIGN THE PROGRAM USING PROGRAM PLANNING TOOLS
- 2.17. CODE AND ENTER THE PROGRAM
- 2.18. COMPILE THE PROGRAM INTO A PROGRAM OBJECT
- 2.19. TEST THE PROGRAM
- 2.20. DEBUGGING PHASES
- 2.21. DEBUGGING TECHNIQUES
- 2.22. DOCUMENT THE PROGRAM
- 2.23. CASE PROBLEM
- 2.24. PROBLEM DEFINITION
- 2.25. INPUT LAYOUT
- 2.26. OUTPUT LAYOUT
- 2.27. PLANNING THE PROGRAM'S DESIGN
- 2.28. INTERPRETING THE FLOWCHART IN FIGURE 2.10
- 2.29. INTERPRETING THE PSEUDOCODE IN FIGURE 2.11
- 2.30. THE PROGRAM ILLUSTRATED
- 2.31. THE COBOL CODING SHEET
- 2.32. THE MAIN BODY OF A COBOL PROGRAM
- 2.33. COLUMN 7: FOR COMMENTS, CONTINUING NONNUMERIC LITERALS, AND STARTING A NEW PAGE
- 2.34. BLANK LINES FOR SEPARATING ENTRIES
- 2.35. AREAS A AND B
- 2.36. AN OVERVIEW OF THE FOUR DIVISIONS
- 2.37. TYPES OF COBOL ENTRIES AND THEIR MARGIN RULES
- 2.38. THE IDENTIFICATION DIVISION
- 2.39. THE IDENTIFICATION DIVISION INSTRUCTION FORMAT
- 2.40. UNDERSTANDING INSTRUCTION FORMATS AS THEY APPEAR IN REFERENCE MANUALS
- 2.41. CODING THE IDENTIFICATION DIVISION
- 2.42. THE ENVIRONMENT DIVISION
- 2.43. CONFIGURATION SECTION
- 2.44. INPUT-OUTPUT SECTION
- 2.45. THE DATA DIVISION
- 2.46. USING THE APOSTROPHE IN COBOL PROGRAMS
- 2.47. THE PROCEDURE DIVISION
- 2.48. SCOPE TERMINATORS
- 2.49. LOOPING WITH THE PERFORM STATEMENT
- 2.50. CREATING AN EXECUTABLE PROGRAM OBJECT
- 2.51. END-OF-CHAPTER AIDS
- 2.52. CHAPTER SELF-TEST
- 2.53. CHAPTER REVIEW QUESTIONS
- 2.54. PROGRAMMING ASSIGNMENTS
- 3. DEFINING FILES AND PROCESSING DATA
- 3.1. CHAPTER OBJECTIVES
- 3.2. SPECIFYING ARRIVAL SEQUENCE AND KEYED SEQUENCE FILES FOR PROCESSING
- 3.3. THE SELECT STATEMENT
- 3.4. THE SELECT STATEMENT FOR AN ARRIVAL SEQUENCE FILE
- 3.5. THE SELECT STATEMENT FOR A KEYED SEQUENCE FILE
- 3.6. THE ASSIGN CLAUSE
- 3.7. THE ORGANIZATION CLAUSE
- 3.8. THE ACCESS CLAUSE
- 3.9. THE RECORD KEY CLAUSE
- 3.10. DEFINING FILES
- 3.11. THE DATA DIVISION
- 3.12. VARIABLE AND CONSTANT DATA
- 3.13. FORMING DATA-NAMES
- 3.14. In COBOL/400, user-defined names must conform to the following rules:
- 3.15. USE PREFIXES OR SUFFIXES WHERE APPROPRIATE
- 3.16. THE FILE SECTION OF THE DATA DIVISION
- 3.17. FILE DESCRIPTION ENTRIES
- 3.18. DEFINING A RECORD WITH RECORD DESCRIPTION ENTRIES
- 3.19. USING LEVEL NUMBERS TO DEFINE FIELDS WITHIN A RECORD
- 3.20. ELEMENTARY AND GROUP FIELDS
- 3.21. INVALID USE OF LEVEL NUMBERS
- 3.22. PICTURE (PIC) CLAUSES
- 3.23. TYPE OF DATA
- 3.24. SIZE OF DATA FIELDS
- 3.25. FORMAT OF THE PIC CLAUSE
- 3.26. THE USE OF THE IMPLIED DECIMAL POINT IN PIC CLAUSES
- 3.27. PACKED-DECIMAL OR COMPUTATIONAL-3 (COMP-3)
- 3.28. MULTIPLE-RECORD TYPES IN DISK FILES
- 3.29. RECORD DESCRIPTION ENTRIES FOR PRINTER FILES
- 3.30. USE OF RESERVED WORD FILLER IN RECORD DESCRIPTION ENTRIES
- 3.31. THE WORKING-STORAGE SECTION OF THE DATA DIVISION
- 3.32. USING AN END-OF-FILE INDICATOR
- 3.33. THE PROCEDURE DIVISION
- 3.34. DEFINING PARAGRAPHS
- 3.35. STATEMENTS AND SENTENCES WITHIN PARAGRAPHS
- 3.36. THE SEQUENCE OF INSTRUCTIONS IN A PROGRAM
- 3.37. STATEMENTS TYPICALLY CODED IN THE MAIN MODULE
- 3.38. OPEN STATEMENT
- 3.39. READ STATEMENT
- 3.40. THE NOT AT END CLAUSE
- 3.41. PERFORM . . . UNTIL STATEMENT: A STRUCTURED PROGRAMMING TECHNIQUE
- 3.42. CORRECTLY SEQUENCING INSTRUCTIONS IN A MODULE
- 3.43. END-OF-JOB PROCESSING: THE CLOSE AND STOP RUN STATEMENTS
- 3.44. CLOSE STATEMENT
- 3.45. STOP RUN STATEMENT
- 3.46. AN INTRODUCTION TO THE MOVE AND WRITE STATEMENTS
- 3.47. SIMPLIFIED MOVE STATEMENT
- 3.48. WRITE STATEMENT
- 3.49. EXTERNALLY DESCRIBED FILES
- 3.50. THE SELECT STATEMENT FOR AN EXTERNALLY DESCRIBED FILE
- 3.51. THE ASSIGN CLAUSE
- 3.52. THE RECORD KEY CLAUSE
- 3.53. FORMAT 2 COPY STATEMENT
- 3.54. USING THE ALIAS KEYWORD
- 3.55. END-OF-CHAPTER AIDS
- 3.56. CHAPTER SELF-TEST
- 3.57. CHAPTER REVIEW QUESTIONS
- 3.58. DEBUGGING EXERCISE 1
- 3.59. DEBUGGING EXERCISE 2
- 3.60. PRACTICE PROGRAM
- 3.61. PROGRAMMING ASSIGNMENTS
- 4. PRINTING REPORTS
- 4.1. CHAPTER OBJECTIVES
- 4.2. TYPES OF REPORTS
- 4.3. DETAIL REPORTS
- 4.4. EXCEPTION REPORTS
- 4.5. SUMMARY OR GROUP REPORTS
- 4.6. THE PRINTER SPACING CHART
- 4.7. PRINTING HEADINGS, DETAIL LINES, AND TOTAL LINES
- 4.8. DEFINING MULTIPLE RECORD TYPES FOR PRINTER FILES
- 4.9. VALUE CLAUSES FOR WORKING-STORAGE ENTRIES
- 4.10. THE WRITE . . . FROM STATEMENT
- 4.11. THE ADVANCING OPTION FOR SPACING LINES
- 4.12. OVERPRINTING
- 4.13. ADVANCING THE PAPER TO A NEW PAGE USING THE PAGE OPTION
- 4.14. PRINTING THE CURRENT SYSTEM DATE ON A REPORT
- 4.15. USING THE RESERVED WORD CURRENT-DATE FIELD.
- 4.16. USING THE RESERVED WORD DATE FIELD.
- 4.17. EDITING PRINTED OUTPUT
- 4.18. EDITING FUNCTIONS
- 4.19. PRINTING DECIMAL POINTS
- 4.20. SUPPRESSING LEADING ZEROS
- 4.21. BE SURE TO SIZE THE REPORT-ITEM CORRECTLY
- 4.22. PRINTING DOLLAR SIGNS AND COMMAS
- 4.23. PRINTING ASTERISKS (*) FOR CHECK PROTECTION
- 4.24. PRINTING PLUS OR MINUS SIGNS
- 4.25. PRINTING DEBIT AND CREDIT SYMBOLS FOR ACCOUNTING APPLICATIONS
- 4.26. PRINTING SPACES OR ZEROS AS SEPARATORS WITHIN FIELDS
- 4.27. DE-EDITING
- 4.28. EDITING USING FLOATING STRINGS
- 4.29. BLANK WHEN ZERO OPTION
- 4.30. THE JUSTIFIED RIGHT OPTION
- 4.31. PRINTING QUOTATION MARKS
- 4.32. CONTROLLING THE SPACING OF PRINTED REPORTS
- 4.33. PRINTING THE HEADINGS ON THE FIRST PAGE
- 4.34. LINE COUNTING FOR SINGLE-SPACED REPORTS
- 4.35. LINE COUNTING FOR DOUBLE-SPACED REPORTS
- 4.36. USING A LINE LIMIT FIELD TO DETERMINE THE NUMBER OF LINES TO PRINT
- 4.37. PRINTING PAGE NUMBERS
- 4.38. USING THE READ . . . INTO STATEMENT IN PLACE OF READ AND MOVE STATEMENTS
- 4.39. CASE PROBLEM
- 4.40. END-OF-CHAPTER AIDS
- 4.41. CHAPTER SELF-TEST
- 4.42. PRACTICE PROGRAM
- 4.43. CHAPTER REVIEW QUESTIONS
- 4.44. PROGRAMMING ASSIGNMENTS
- 5. DESIGNING STRUCTURED PROGRAMS
- 5.1. CHAPTER OBJECTIVES
- 5.2. WRITING WELL-DESIGNED PROGRAMS
- 5.3. PROGRAMS SHOULD USE A TOP-DOWN MODULAR APPROACH
- 5.4. PROGRAMS SHOULD BE STRUCTURED
- 5.5. PROGRAM LOGIC SHOULD BE MAPPED OUT USING A PLANNING TOOL
- 5.6. HIERARCHY CHARTS FOR TOP-DOWN PROGRAMMING
- 5.7. NAMING MODULES OR PARAGRAPHS
- 5.8. MODULARIZING PROGRAMS USING PERFORM STATEMENTS
- 5.9. DESIGNING THE LOGIC BEFORE CODING A PROGRAM
- 5.10. FLOWCHARTS
- 5.11. PSEUDOCODE: STANDARD AND STRUCTURED
- 5.12. THE FOUR LOGICAL CONTROL STRUCTURES
- 5.13. SEQUENCE
- 5.14. SELECTION
- 5.15. ITERATION
- 5.16. THE INFINITE LOOP: AN ERROR TO BE AVOIDED
- 5.17. CASE STRUCTURE
- 5.18. STRUCTURED PROGRAMMING CODING GUIDELINES
- 5.19. INDENT LINES WITHIN A SENTENCE
- 5.20. CASE PROBLEM
- 5.21. END-OF-CHAPTER AIDS
- 5.22. CHAPTER SELF-TEST
- 5.23. CHAPTER REVIEW QUESTIONS
- 5.24. PRACTICE PROGRAM #1
- 5.25. PRACTICE PROGRAM #2
- 5.26. PROGRAMMING ASSIGNMENTS
- 6. MOVING DATA AND TEXT MANIPULATION
- 6.1. CHAPTER OBJECTIVES
- 6.2. THE INSTRUCTION FORMATS OF THE MOVE STATEMENT
- 6.3. The two instruction formats for the MOVE statement are
- 6.4. NUMERIC MOVE
- 6.5. WHEN SENDING AND RECEIVING FIELDS HAVE THE SAME PIC CLAUSES
- 6.6. WHEN SENDING AND RECEIVING FIELDS HAVE DIFFERENT PIC CLAUSES
- 6.7. AVOIDING TRUNCATION
- 6.8. MOVING NUMERIC LITERALS TO NUMERIC FIELDS
- 6.9. MOVING SIGNED NUMBERS
- 6.10. ALPHANUMERIC OR NONNUMERIC MOVE
- 6.11. MOVING LITERALS TO ALPHANUMERIC (NONNUMERIC) FIELDS
- 6.12. A GROUP MOVE IS CONSIDERED AN ALPHANUMERIC (NONNUMERIC) MOVE
- 6.13. DECIMAL DATA ERROR
- 6.14. MOVING FIGURATIVE CONSTANTS
- 6.15. SUMMARY OF MOVE OPERATIONS
- 6.16. MOVING DATA WITH TEXT MANIPULATION
- 6.17. TEXT MANIPULATION WITH THE STRING STATEMENT
- 6.18. GENERAL RULES FOR USING THE STRING
- 6.19. CASE PROBLEM
- 6.20. END-OF-CHAPTER AIDS
- 6.21. CHAPTER SELF-TEST
- 6.22. CHAPTER REVIEW QUESTIONS
- 6.23. DEBUGGING EXERCISES
- 6.24. PRACTICE PROGRAM
- 6.25. PROGRAMMING ASSIGNMENTS
- 7. COMPUTING IN COBOL: THE ARITHMETIC VERBS
- 7.1. CHAPTER OBJECTIVES
- 7.2. THE FOUR BASIC ARITHMETIC OPERATIONS
- 7.3. ADD STATEMENT
- 7.4. FIELDS USED IN AN ADD
- 7.5. USING FORMAT 1 OF THE ADD STATEMENT
- 7.6. USING FORMAT 2 OF THE ADD STATEMENT
- 7.7. USING FORMAT 3 OF THE ADD STATEMENT
- 7.8. DECIDING WHETHER TO USE THE TO OR GIVING FORMAT
- 7.9. ADDING MORE THAN TWO FIELDS
- 7.10. PRODUCING MORE THAN ONE SUM
- 7.11. SUBTRACT STATEMENT
- 7.12. DECIDING WHICH FORMAT TO USE
- 7.13. MULTIPLY STATEMENT
- 7.14. EXAMPLE OF ARITHMETIC OPERATIONS THAT USE THE MULTIPLY OPERATION
- 7.15. STORING INTERMEDIATE RESULTS
- 7.16. DIVIDE STATEMENT
- 7.17. USE OF THE REMAINDER CLAUSE IN THE DIVIDE OPERATION
- 7.18. OPTIONS AVAILABLE WITH ARITHMETIC VERBS
- 7.19. HOW ROUNDING IS ACCOMPLISHED
- 7.20. ON SIZE ERROR OPTION
- 7.21. AVOIDING SIZE ERRORS
- 7.22. DIVIDING BY ZERO CAUSES A SIZE ERROR
- 7.23. NOT ON SIZE ERROR CLAUSE
- 7.24. DETERMINING THE SIZE OF RECEIVING FIELDS
- 7.25. USING SCOPE TERMINATORS
- 7.26. THE COMPUTE STATEMENT
- 7.27. SPACING RULES WITH A COMPUTE
- 7.28. THE COMPUTE WITH AND WITHOUT ROUNDING
- 7.29. ORDER OF EVALUATION
- 7.30. COMPARING COMPUTE TO ARITHMETIC VERBS
- 7.31. SIGNED NUMBERS IN ARITHMETIC OPERATIONS FOR FIELDS THAT CAN BE NEGATIVE
- 7.32. RULES FOR PERFORMING ARITHMETIC WITH SIGNED NUMBERS
- 7.33. ENTERING A SIGN SEPARATE FROM THE DATA
- 7.34. CLEARING FIELDS USING THE INITIALIZE STATEMENT
- 7.35. LIKE CLAUSE
- 7.36. DISPLAY STATEMENT
- 7.37. CASE PROBLEM # 1
- 7.38. CASE PROBLEM # 2
- 7.39. END-OF-CHAPTER AIDS
- 7.40. CHAPTER SELF-TEST
- 7.41. CHAPTER REVIEW QUESTIONS
- 7.42. DEBUGGING EXERCISES
- 7.43. PRACTICE PROGRAM
- 7.44. PROGRAMMING ASSIGNMENTS
- 8. DECISION-MAKING USING THE IF AND EVALUATE STATEMENTS
- 8.1. CHAPTER OBJECTIVES
- 8.2. LOGICAL CONTROL STRUCTURES
- 8.3. THE IF CONDITIONAL STATEMENT
- 8.4. THE INSTRUCTION FORMAT FOR AN IF STATEMENT
- 8.5. A SIMPLE IF STATEMENT
- 8.6. AN IF STATEMENT WITH ELSE CLAUSE
- 8.7. RELATIONAL OPERATORS
- 8.8. NUMERIC FIELDS SHOULD NOT CONTAIN BLANKS
- 8.9. HOW COMPARISONS ARE PERFORMED
- 8.10. EBCDIC COLLATING SEQUENCE
- 8.11. ENDING CONDITIONAL SENTENCES WITH A PERIOD OR AN END-IF SCOPE TERMINATOR
- 8.12. THE CONTINUE CLAUSE
- 8.13. NESTED CONDITIONAL IF STATEMENT
- 8.14. COMPOUND CONDITIONAL
- 8.15. OR IN A COMPOUND CONDITIONAL
- 8.16. LIMITATIONS ON A COMPOUND CONDITIONAL
- 8.17. IMPLIED OPERANDS
- 8.18. AND IN A COMPOUND CONDITIONAL
- 8.19. USING AND AND OR IN THE SAME STATEMENT
- 8.20. ORDER OF EVALUATION OF COMPOUND CONDITIONALS
- 8.21. THE EVALUATE STATEMENT: THE CASE STRUCTURE
- 8.22. DATA VALIDATION
- 8.23. THE SIGN TEST
- 8.24. TESTING FOR REASONABLENESS
- 8.25. THE CLASS TEST
- 8.26. CHECKING FOR MISSING DATA
- 8.27. ALPHABETIC CLASS TEST
- 8.28. NEGATING CONDITIONALS
- 8.29. CONDITION-NAMES: CHECKING CODED FIELDS FOR VALID CONTENTS
- 8.30. SET STATEMENT
- 8.31. CASE PROBLEM
- 8.32. END-OF-CHAPTER AIDS
- 8.33. CHAPTER SELF-TEST
- 8.34. REVIEW QUESTIONS
- 8.35. PROGRAMMING ASSIGNMENTS
- 9. ITERATION: BEYOND THE BASIC PERFORM
- 9.1. CHAPTER OBJECTIVES
- 9.2. THE SIMPLE PERFORM REVIEWED
- 9.3. IN-LINE PERFORM STATEMENT
- 9.4. MODULARIZING PROGRAMS USING PERFORM STATEMENTS
- 9.5. NESTED PERFORM: A PERFORM WITHIN A PERFORM
- 9.6. EXECUTING A GROUP OF PARAGRAPHS WITH A SIMPLE PERFORM
- 9.7. ITERATION USING OTHER TYPES OF PERFORMS
- 9.8. ITERATION USING THE PERFORM . . . UNTIL STATEMENT
- 9.9. CODING A LOOP WITH A PERFORM ... UNTIL: AN EXAMPLE
- 9.10. A PERFORM ... UNTIL TESTS FOR THE CONDITION FIRST
- 9.11. AVOIDING THE INFINITE LOOP
- 9.12. ITERATION USING THE PERFORM ... TIMES STATEMENT
- 9.13. CODING A LOOP WITH A PERFORM ... TIMES: AN EXAMPLE
- 9.14. USING A VARIABLE FIELD IN A PERFORM . . . TIMES STATEMENT
- 9.15. THE PERFORM ... VARYING STATEMENT
- 9.16. USING NESTED PERFORM ... VARYING STATEMENTS
- 9.17. PERFORM ... VARYING: EXAMPLE 2
- 9.18. THE PERFORM WITH TEST AFTER OPTION
- 9.19. WHICH ITERATION STATEMENT TO USE
- 9.20. END-OF-CHAPTER-AIDS
- 9.21. CHAPTER SELF-TEST
- 9.22. CHAPTER REVIEW QUESTIONS
- 9.23. PROGRAMMING ASSIGNMENTS
- 10. THE COPY AND CALL STATEMENTS
- 10.1. CHAPTER OBJECTIVES
- 10.2. THE COPY STATEMENT
- 10.3. ENTRIES THAT CAN BE COPIED
- 10.4. THE FULL FORMAT FOR THE COPY STATEMENT
- 10.5. CASE PROBLEM CPCH10A
- 10.6. MODULAR PROGRAMMING
- 10.7. THE CALL STATEMENT
- 10.8. LINKAGE TYPE PHRASE
- 10.9. IN LIBRARY PHRASE
- 10.10. USING PHASE
- 10.11. THE BY CONTENT CLAUSE
- 10.12. GROUPING DATA TO BE PASSED
- 10.13. CALLED PROGRAM REQUIREMENTS
- 10.14. DYNAMIC (EXTERNAL) AND STATIC BINDING
- 10.15. DYNAMIC (EXTERNAL) PROGRAM CALLS
- 10.16. STATIC PROGRAM CALLS
- 10.17. THE CREATE BOUND COBOL (CRTBNDCBL) COMMAND
- 10.18. CASE PROBLEM CPCH10B
- 10.19. CASE PROBLEM CPCH10C
- 10.20. END-OF-CHAPTER AIDS
- 10.21. CHAPTER SELF-TEST
- 10.22. CHAPTER REVIEW QUESTIONS
- 10.23. PROGRAMMING ASSIGNMENTS
- 11. LOGICAL FILES
- 11.1. CHAPTER OBJECTIVES
- 11.2. LOGICAL FILES
- 11.3. USING A SIMPLE LOGICAL FILE TO ENSURE THE DATA FILE IS IN THE CORRECT SEQUENCE
- 11.4. USING A LOGICAL FILE IN A COBOL/400 PROGRAM
- 11.5. SELECTING SPECIFIC FIELDS WITH A LOGICAL FILE
- 11.6. SELECTING AND OMITTING RECORDS USING LOGICAL FILES
- 11.7. ORED COMPARISIONS
- 11.8. ANDED COMPARISONS
- 11.9. CREATING A LOGICAL FILE
- 11.10. LOGICAL FILE WITH MULTIPLE-RECORD FORMATS
- 11.11. JOIN LOGICAL FILES
- 11.12. JOIN LOGICAL FILE CONCEPTS
- 11.13. HOW TO CODE JOIN FILES
- 11.14. EXAMPLE 1: JOINING TWO FILES AND USING DEFAULT VALUES FOR UNMATCHED RECORDS
- 11.15. EXAMPLE 2: JOINING TWO FILES AND SEQUENCING MULTIPLE MATCHES FROM A SECONDARY FILE
- 11.16. EXAMPLE 3: JOINING FOUR FILES
- 11.17. JOIN LOGICAL FILE KEYWORD DEFINITIONS
- 11.18. END-OF-CHAPTER AIDS
- 11.19. CHAPTER SELF-TEST
- 11.20. CHAPTER REVIEW QUESTIONS
- 11.21. PROGRAMMING ASSIGNMENTS
- 12. CONTROL BREAK PROCESSING
- 12.1. CHAPTER OBJECTIVES
- 12.2. DETAIL AND SUMMARY REPORTS
- 12.3. CASE PROBLEM #1: AN EXAMPLE OF A CONTROL BREAK PROCEDURE
- 12.4. USING A LOGICAL FILE IN A CONTROL BREAK PROGRAM
- 12.5. THE CONTROL BREAK PROCEDURE
- 12.6. PROGRAM REQUIREMENTS FOR SINGLE-LEVEL CONTROL BREAK PROCESSING
- 12.7. FORCING A CONTROL BREAK WHEN THERE ARE NO MORE RECORDS
- 12.8. REFINEMENTS TO IMPROVE THE QUALITY OF A CONTROL BREAK REPORT
- 12.9. PRINTING A FINAL TOTAL
- 12.10. GROUP SUPPRESSION OF A CONTROL FIELD
- 12.11. PRINTING THE CONTROL FIELD WITH THE CONTROL BREAK TOTAL LINE
- 12.12. EXECUTING THE CONTROL BREAK MODULE FROM THE MAIN MODULE AFTER AN END-OF-FILE CONDITION HAS BEEN MET
- 12.13. CASE PROBLEM #2: MULTIPLE-LEVEL CONTROL BREAKS
- 12.14. STARTING A NEW PAGE AFTER EACH CONTROL BREAK
- 12.15. END-OF-CHAPTER-AIDS
- 12.16. CHAPTER SELF-TEST QUESTIONS
- 12.17. CHAPTER REVIEW QUESTIONS
- 12.18. PROGRAMMING ASSIGNMENTS
- 13. RANDOM FILE ACCESS FOR KEYED FILES
- 13.1. CHAPTER OBJECTIVES
- 13.2. ACCESSING A KEYED FILE RANDOMLY
- 13.3. THE SELECT STATEMENT
- 13.4. THE READ STATEMENT
- 13.5. INVALID KEY CLAUSE
- 13.6. READING DATA RANDOMLY AS NEEDED: AN EXAMPLE
- 13.7. UPDATING A KEYED FILE RANDOMLY
- 13.8. OPENING A KEYED FILE AS I-O
- 13.9. REWRITE A RECORD TO UPDATE IT
- 13.10. THE INVALID KEY CLAUSE
- 13.11. DELETING RECORDS FROM A KEYED FILE
- 13.12. CASE PROBLEM: A FULL UPDATE PROCEDURE
- 13.13. ADDING NEW RECORDS TO A KEYED FILE
- 13.14. UPDATING OR CHANGING EXISTING RECORDS IN A KEYED FILE
- 13.15. DELETING RECORDS FROM A KEYED FILE
- 13.16. UPDATING A KEYED FILE WITH MULTIPLE TRANSACTION RECORDS FOR EACH KEYED RECORD
- 13.17. PROCESSING A KEYED FILE WITHIN LIMITS
- 13.18. THE START STATEMENT
- 13.19. CHECKING FOR THE UPPER LIMIT
- 13.20. ACCESSING A KEYED FILE DYNAMICALLY THE ACCESS IS DYNAMIC CLAUSE
- 13.21. THE READ ... NEXT RECORD INSTRUCTION
- 13.22. A REVIEW OF INVALID KEY CLAUSES
- 13.23. THE FILE STATUS CLAUSE
- 13.24. EXCEPTION HANDLING WITH THE USE STATEMENT
- 13.25. END-OF-CHAPTER AIDS
- 13.26. CHAPTER SELF-TEST
- 13.27. CHAPTER REVIEW QUESTIONS
- 13.28. DEBUGGING EXERCISES
- 13.29. PRACTICE PROGRAM #1
- 13.30. PRACTICE PROGRAM #2
- 13.31. PROGRAMMING ASSIGNMENTS
- 14. INTERACTIVE PROGRAMMING
- 14.1. CHAPTER OBJECTIVES
- 14.2. BATCH VERSUS INTERACTIVE PROCESSING
- 14.3. INTERACTIVE PROCESSING
- 14.4. DISPLAY FILES
- 14.5. TYPES OF RECORD FORMATS USED IN DISPLAY FILES
- 14.6. MENU FORMAT
- 14.7. INFORMATIONAL OR QUERY FORMAT
- 14.8. DATA ENTRY FORMAT
- 14.9. List or Work With Format
- 14.10. ELEMENTS OF A RECORD FORMAT
- 14.11. ATTRIBUTES
- 14.12. SETTING ATTRIBUTES WITH THE COLOR KEYWORD
- 14.13. SETTING ATTRIBUTES WITH THE DSPATR KEYWORD
- 14.14. CASE PROBLEM: AN INTERACTIVE QUERY PROGRAM
- 14.15. DEFINING THE DDS FOR A DISPLAY FILE
- 14.16. DEFINING THE FILE-LEVEL KEYWORDS FOR THE DISPLAY FILE
- 14.17. USING INDICATORS IN INTERACTIVE PROGRAMS
- 14.18. DEFINING THE DDS FOR RECORD FORMAT SCREEN1
- 14.19. USING COLOR TO DEFINE ATTRIBUTES
- 14.20. DATE KEYWORD
- 14.21. DEFINING THE DDS FOR RECORD FORMAT SCREEN2
- 14.22. EDITING NUMERIC FIELDS
- 14.23. EDTCDE KEYWORD
- 14.24. DISPLAYING NEGATIVE VALUES
- 14.25. ZERO SUPPRESSION
- 14.26. DISPLAYING DOLLAR SIGNS
- 14.27. USING EDIT WORDS
- 14.28. CREATING THE DISPLAY FILE OBJECT
- 14.29. THE INTERACTIVE PROGRAM
- 14.30. ESTABLISHING A TRANSACTION FILE
- 14.31. THE ASSIGN CLAUSE
- 14.32. DEFINING INDICATORS IN A SEPARATE INDICATOR AREA
- 14.33. THE CONTROL-AREA CLAUSE
- 14.34. PROCESSING DISPLAY FILE INPUT/OUTPUT (I/O) OPERATIONS
- 14.35. READ OPERATION
- 14.36. PROCEDURE DIVISION SPECIFICATIONS
- 14.37. TERMINATING A WORKSTN PROGRAM
- 14.38. CASE PROBLEM: AN INTERACTIVE FILE MAINTENANCE
- 14.39. DATA VALIDATION TECHNIQUES FOR DISPLAY FILES
- 14.40. COBOL/400 FILE MAINTANANCE PROGRAM
- 14.41. THE MOVE CORRESPONDING STATEMENT
- 14.42. END-OF-CHAPTER AIDS
- 14.43. CHAPTER SELF-TEST
- 14.44. CHAPTER REVIEW QUESTIONS
- 14.45. PROGRAMMING ASSIGNMENTS
- 15. SINGLE-LEVEL ARRAYS AND TABLES
- 15.1. CHAPTER OBJECTIVES
- 15.2. AN INTRODUCTION TO SINGLE-LEVEL OCCURS CLAUSES
- 15.3. USING AN OCCURS CLAUSE IN WORKING-STORAGE
- 15.4. USING LIKE CLAUSE WITH OCCURS CLAUSE
- 15.5. VALIDATING INPUT DATA
- 15.6. RULES FOR USE OF THE OCCURS CLAUSE
- 15.7. DEFINING ELEMENTARY OR GROUP ITEMS WITH AN OCCURS CLAUSE
- 15.8. ACCESSING WORKING-STORAGE AREAS DEFINED BY AN OCCURS CLAUSE
- 15.9. PROCESSING DATA STORED IN AN ARRAY
- 15.10. PRINTING DATA STORED IN AN ARRAY
- 15.11. PRINTING SUBSCRIPTED VARIABLES IN A VARIETY OF WAYS
- 15.12. USING AN OCCURS CLAUSE FOR TABLE HANDLING
- 15.13. WHY TABLES ARE USED
- 15.14. STORING THE TABLE IN WORKING-STORAGE
- 15.15. USING THE READ ... INTO TO LOAD A TABLE
- 15.16. VALIDATING DATA
- 15.17. LOOKING UP DATA IN A TABLE: FINDING A MATCH
- 15.18. USE OF THE SEARCH STATEMENT FOR TABLE AND ARRAY PROCESSING
- 15.19. USING THE SEARCH ... AT END FOR DATA VALIDATION
- 15.20. THE INDEXED BY CLAUSE AND THE SEARCH STATEMENT
- 15.21. HOW AN INDEX DIFFERS FROM A SUBSCRIPT
- 15.22. MODIFYING THE CONTENTS OF AN INDEX
- 15.23. USING TWO WHEN CLAUSES FOR AN EARLY EXIT FROM A SEARCH
- 15.24. WHEN PART-NUMBERS DO NOT NEED TO BE STORED
- 15.25. SEARCHING FOR MULTIPLE MATCHES
- 15.26. INTERNAL VERSUS EXTERNAL TABLES
- 15.27. LOOKING UP TABLE DATA FOR ACCUMULATING TOTALS
- 15.28. THE SEARCH ... VARYING OPTION FOR PROCESSING PARALLEL TABLES
- 15.29. DEFINITION OF A SERIAL SEARCH
- 15.30. THE BINARY SEARCH
- 15.31. DEFINITION OF A BINARY SEARCH
- 15.32. THE SEARCH ALL STATEMENT
- 15.33. ASCENDING OR DESCENDING KEY WITH THE SEARCH ALL STATEMENT
- 15.34. END-OF-CHAPTER AIDS
- 15.35. CHAPTER SELF-TEST
- 15.36. CHAPTER REVIEW QUESTIONS
- 15.37. DEBUGGING EXERCISES
- 15.38. PRACTICE PROGRAM
- 15.39. PROGRAMMING ASSIGNMENTS
- 16. MULTIPLE-LEVEL ARRAYS AND TABLES
- 16.1. CHAPTER OBJECTIVES
- 16.2. DOUBLE-LEVEL OCCURS CLAUSE
- 16.3. DEFINING A DOUBLE-LEVEL, OR TWO-DIMENSIONAL, ARRAY
- 16.4. USING SUBSCRIPTS WITH DOUBLE-LEVEL OCCURS ENTRIES
- 16.5. ACCESSING A DOUBLE-LEVEL, OR TWO-DIMENSIONAL, ARRAY
- 16.6. THE PERFORM ... VARYING WITH THE AFTER OPTION
- 16.7. USING NESTED PERFORMS
- 16.8. USING PERFORM ... VARYING ... AFTER
- 16.9. USING A DOUBLE-LEVEL, OR TWO-DIMENSIONAL, ARRAY FOR ACCUMULATING TOTALS
- 16.10. LOADING INPUT DATA INTO A DOUBLE-LEVEL, OR TWO-DIMENSIONAL, ARRAY
- 16.11. PERFORMING A LOOK-UP USING A DOUBLE-LEVEL OCCURS
- 16.12. THE IDENTIFIER USED WITH THE SEARCH REFERS TO THE LOWEST-LEVEL OCCURS ENTRY
- 16.13. SEARCHING ONLY PART OF A TABLE
- 16.14. VARYING ONLY ONE INDEX
- 16.15. SEARCHING ELEMENTS IN AN ARRAY
- 16.16. SEARCHING AN ARRAY UNTIL A MATCH IS FOUND
- 16.17. SEARCHING AN ENTIRE ARRAY FOR MULTIPLE MATCHES
- 16.18. TRIPLE-LEVEL OCCURS CLAUSES AND MORE
- 16.19. END-OF-CHAPTER AIDS
- 16.20. CHAPTER SELF-TEST
- 16.21. DEBUGGING EXERCISES
- 16.22. PRACTICE PROGRAM
- 16.23. PROGRAMMING ASSIGNMENTS
- 17. SUBFILE PROGRAMMING
- 17.1. CHAPTER OBJECTIVES
- 17.2. LIST SCREEN OR WORK WITH SCREEN
- 17.3. SUBFILE RECORD FORMATS
- 17.4. DESIGNING SCREEN FORMATS FOR AN INTERACTIVE SUBFILE PROGRAM
- 17.5. THE PROMPT RECORD FORMAT-SFLPROMPT
- 17.6. DEFINING SUBFILE RECORD FORMATS
- 17.7. THE SUBFILE RECORD FORMAT—SFLRECORD
- 17.8. THE SUBFILE CONTROL-RECORD FORMAT-SFLCONTROL
- 17.9. LOADING THE SUBFILE
- 17.10. CASE PROBLEM #1—LOAD-ALL SUBFILE
- 17.11. THE LOAD-ALL SUBFILE PROGRAM
- 17.12. ESTABLISHING A SUBFILE TRANSACTION FILE
- 17.13. ACCESS IS DYNAMIC CLAUSE
- 17.14. THE RELATIVE KEY CLAUSE
- 17.15. THE CONTROL-AREA CLAUSE
- 17.16. FILE STATUS CLAUSE
- 17.17. DEFINING INDICATORS AND FUNCTION KEYS IN SEPARATE AREAS
- 17.18. QUALIFICATION OF NAMES
- 17.19. WRITING TO A SUBFILE TRANSACTION FILE
- 17.20. PROCEDURE DIVISION SPECIFICATIONS
- 17.21. EXPANDING SUBFILE
- 17.22. SINGLE-PAGE-AT-A-TIME SUBFILE
- 17.23. CASE PROBLEM #2: AN INTERACTIVE SUBFILE UPDATE
- 17.24. UPDATING RECORDS IN A SUBFILE
- 17.25. END-OF-CHAPTER AIDS
- 17.26. CHAPTER SELF-TEST
- 17.27. CHAPTER REVIEW QUESTIONS
- 17.28. PROGRAMMING ASSIGNMENTS
- A. THE 5250 KEYBOARD
- B. COBOL CHARACTER SET AND RESERVED WORDS
- C. CRTBNDCBL COMMAND AND PROCESS STATEMENT
EBCDIC, which stands for Extended Binary Coded Decimal Interchange Code and is pronounced eb-ce-dick, is used to represent letters, digits, the character blank, and special characters. The chart shown in Figure B.1 illustrates, in ascending sequence, the EBCDIC collating sequence codes for letters, numbers, and the character blank. In addition, the chart shows the binary representation and hexadecimal codes used by the computer to represent EBCDIC codes.
In COBOL, the primary unit of data is the character. In the COBOL/400 language, the letters of the alphabet, digits, and special characters that form the COBOL character set are represented by a subset of the EBCDIC character set. Figure B.2 shows the complete set of COBOL characters with their meanings and uses.
COBOL/400 incorporates many enhancements that are not incorporated in the ANSI COBOL 85 Standard. Among them are extensions that aid in writing interactive workstation applications as well as support for externally described files.
With these extensions to COBOL/400, IBM introduced several reserved words that have special meaning. A reserved word is a word or character-string with a predefined meaning in a COBOL source program. A reserved word must not be used as a user-defined word or as a system-name. Reserved words can be used only as specified in the formats for a COBOL source program.
Figure B.3 contains a list of COBOL reserved words. In addition to the reserved words unique to COBOL/400, there are many reserved words in the ANSI Standard that are not used by the COBOL/400 compiler. If used, a diagnostic message will be generated. Reserved words that have special meaning or are not valid with the COBOL/400 compiler are identified in Figure B.3 with a number within parenthesis. The blank or number within parenthesis represents the following:
Blank | A COBOL/400 reserved word from the 1985 ANSI Standard. |
1 | A COBOL/400 reserved word that is an IBM extension to the 1985 ANSI Standard. |
2 | A COBOL reserved word from the 1985 ANSI Standard that is not used by the COBOL/400 compiler. These words should not be used. If used, a diagnostic message will be issued. |
3 | A COBOL reserved word that is not in the 1985 ANSI Standard and is not supported by the COBOL/400 compiler. If used, a diagnostic message will be issued. |
4 | A COBOL reserved word that is supported by the COBOL/400 compiler when *EXTACCDSP is specified in the CRTCBLPGM CL command, or when EXTACCDSP is used in the PROCESS statement. |
When defining alphanumeric literals, iSeries Servers and the AS/400 expect the literals to be defined within quotation marks ("). The apostrophe (') can also be used in place of quotation marks. If the apostrophe is used, the compiler will generate a warning error for each alphanumeric literal defined within apostrophes. To have the COBOL/400 compiler accept the apostrophes and not produce warning errors, you should override the default compiler option with the PROCESS statement. See Appendix C for information about the PROCESS statement.
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