Murach's Mainframe COBOL

by Murach, Mike; Prince, Anne; Menendez, Raul

• ISBN13: 9781890774240
• ISBN10: 1890774243
• Format: Paperback
• Copyright: 2004-08-31
• Publisher: Mike Murach & Associates Inc

Summary

This has been the number 1 best-selling COBOL book for professional programmers since its first edition in 1979. It is the only book that shows how to design, code, test, and maintain structured COBOL programs on the IBM mainframes (or enterprise systems) that are used by the largest companies in the world. Besides COBOL, this book presents the IBM products that every mainframe programmer needs to know including TSO, ISPF, OS/390 JCL, VSAM Access Method Services, CICS, and DB2.

Table of Contents

The essence of COBOL programming
Introduction to COBOL programming
COBOL platforms, standards, and compilers	p. 4
COBOL platforms	p. 4
COBOL standards and mainframe compilers	p. 6
An interactive COBOL program	p. 8
An interactive session	p. 8
The COBOL code	p. 10
Basic coding rules	p. 12
How to code the Identification Division	p. 14
How to code the Environment Division	p. 14
How to code the Working-Storage Section	p. 16
How to create data names	p. 16
How to code Picture clauses	p. 18
How to code Value clauses	p. 20
How to code group items	p. 22
How to code the Procedure Division	p. 24
How to create procedure names	p. 24
How to code Accept statements	p. 26
How to code Display statements	p. 28
How to code Move statements	p. 30
How to code Compute statements	p. 32
How to code arithmetic expressions	p. 34
How to code Add statements	p. 36
How to code If statements	p. 38
How to code Perform statements	p. 40
How to code Perform Until statements	p. 40
How to code the Stop Run statement	p. 40
Another interactive COBOL program	p. 42
An interactive session	p. 42
The COBOL code	p. 44
How to compile, test, and debug a COBOL program
Introduction to compiling and testing	p. 48
How a COBOL program is compiled, link-edited, and executed	p. 48
A basic procedure for developing COBOL programs	p. 50
The basic skills for compiling and testing a program	p. 52
How to enter and edit a source program	p. 52
How to compile and run a program	p. 54
How to review the diagnostic messages for compile-time errors	p. 56
How to correct compile-time errors	p. 58
How to review the message for a run-time error	p. 60
How to correct a run-time error	p. 62
How debugging tools can make debugging easier	p. 64
How to use COBOL statements to get debugging information	p. 66
How to write a program that prepares a report
A simple report-preparation program	p. 70
The file specifications	p. 70
The report specifications	p. 72
The COBOL code	p. 74
How to code Select statements and FD statements	p. 82
How to code Select statements on a mainframe	p. 82
How to code FD statements and record descriptions for disk files	p. 84
How to code FD statements and record descriptions for print files	p. 84
How to code the Procedure Division	p. 86
How to code Open and Close statements	p. 86
How to code Read statements for sequential disk files	p. 88
How to code Write statements for print files	p. 88
How to use the Current-Date function to get the current date and time	p. 90
How to use Accept statements to get the current date and time	p. 92
An enhanced version of the report-preparation program	p. 94
The enhanced report specifications	p. 94
The changes to the Data Division code	p. 96
The changes to the Procedure Division code	p. 98
How to test a report-preparation program	p. 100
How to prepare a test plan and test data	p. 100
Common run-time errors	p. 102
How to design, code, and test a structured program
How to develop a structured program	p. 106
A complete procedure for developing a structured program	p. 106
The specifications for a summary report-preparation program	p. 108
How to design a structured program	p. 110
The terms for working with a structure chart	p. 110
How to name the modules in a chart	p. 110
How to design the first two levels of a chart	p. 112
How to design the legs of a chart	p. 114
How to add the Read and Write modules to a chart	p. 116
How to number the modules in a chart	p. 118
How to draw charts that won't fit on one page	p. 118
Alternatives to the structure chart	p. 120
When and how to use pseudocode	p. 122
The basics of using pseudocode	p. 122
How to use pseudocode for the critical modules of a program	p. 124
How to code each module so it is independent	p. 126
How to code and test a program from the top down	p. 128
How to plan the coding and testing sequence	p. 128
How to code the new modules for each phase of testing	p. 130
How to code program stubs	p. 132
The code for the summary report-preparation program	p. 134
The Data Division code	p. 134
The Procedure Division code	p. 136
How COBOL programming compares to object-oriented programming	p. 142
How to use the COBOL features for structured coding
Introduction to structured programming	p. 146
The three valid structures	p. 146
The principles of substitution and combination	p. 148
From theory to practice	p. 148
Shop standards for structured coding	p. 150
How to code conditions	p. 152
How to code relation, sign, and class tests	p. 152
How to code compound conditions	p. 154
How to code and use condition names	p. 156
How to code selection and iteration structures	p. 158
How to code If statements	p. 158
How to code nested If statements	p. 160
How to code Perform Until statements with tests before and after	p. 162
When and how to code inline Perform statements	p. 164
How to code Perform statements with Varying and Times clauses	p. 166
How to use Evaluate statements	p. 168
How to use an Evaluate statement instead of nested If statements	p. 168
How to use Evaluate statements to implement case structures	p. 170
The complete syntax of the Evaluate statement	p. 172
Other features for improved coding	p. 174
How to use Set to True statements	p. 174
When and how to use structured delimiters	p. 176
When and how to use Not clauses	p. 178
A program that prepares a two-level summary report	p. 180
The program specifications	p. 180
The structure chart	p. 182
The COBOL code for the primary control module	p. 184
Three paragraphs written with a modern coding style	p. 186
Other ways to define, move, and initialize fields
How to define fields in the Data Division	p. 190
When to omit the word Filler	p. 190
How to code literals and figurative constants	p. 192
How to code Picture, Value, and Blank When Zero clauses	p. 194
How to code Usage clauses	p. 196
How to code Redefines clauses	p. 198
How to use Move and Initalize statements	p. 200
How to code Move statements	p. 200
How to code Pictures for alphanumeric and numeric editing	p. 202
How to code Initialize statements	p. 204
Usages and data formats on an IBM mainframe	p. 206
IBM mainframe extensions to the standard usages	p. 206
Binary, hex, and EBCDIC notation	p. 208
The primary formats for numeric data	p. 210
An enhanced report-preparation program	p. 212
The changes to the one-level summary report	p. 212
The changes to the Working-Storage code	p. 212
The changes to the Procedure Division code	p. 214
Other COBOL essentials
How to use arithmetic statements and intrinsic functions
How to code arithmetic statements	p. 220
How to code Compute statements	p. 220
How to code arithmetic expressions	p. 222
How to code Add and Subtract statements	p. 224
How to code Multiply and Divide statements	p. 226
How to use intrinsic functions	p. 228
A summary of the six types of functions	p. 228
How to code any function	p. 230
How to use the mathematical functions	p. 232
How to use the statistical functions	p. 234
How to use the financial functions	p. 236
How to work with dates
How to use Accept statements and the date functions	p. 240
How to use Accept Date and Accept Time statements	p. 240
How to use Accept Day and Accept Day-Of-Week statements	p. 242
How to use the functions for working with dates	p. 244
The Y2K problem and its solutions	p. 246
The Y2K problem	p. 246
The Y2K solutions: Date expansion and century windowing	p. 248
How to use IBM's Millennium Language Extensions	p. 250
How to define date fields with the Date Format clause	p. 250
How to work with date fields in the Procedure Division	p. 252
How to work with characters
How to use reference modification and functions	p. 256
How to use reference modification	p. 256
How to use the functions for working with characters	p. 258
How to use the String and Unstring statements	p. 260
How to use the String statement	p. 260
How to use the Unstring statement	p. 262
How to use the Inspect statement	p. 264
With the Tallying clause	p. 264
With the Replacing clause	p. 266
With the Tallying and Replacing clauses	p. 268
With the Converting clause	p. 270
Two illustrative routines	p. 272
An editing routine	p. 272
A conversion routine	p. 272
How to work with tables
How to use subscripts to work with one-level tables	p. 276
How to define a one-level table that uses subscripts	p. 276
How to initialize a table	p. 278
How to define a table with constant values	p. 278
How to refer to entries in a one-level table using subscripts	p. 280
How to load a one-level table using subscripts	p. 282
How to search a one-level table using subscripts	p. 284
How to use subscripts to work with multi-level tables	p. 286
How to define a multi-level table	p. 286
How to refer to entries in a multi-level table using subscripts	p. 288
How to load a two-level table using subscripts	p. 288
How to search a two-level table using subscripts	p. 290
How to use indexes to work with tables	p. 292
How to define a table with an index	p. 292
How to refer to table entries using an index	p. 292
How to load a table using an index	p. 294
How to code the Set statement	p. 296
How to perform a sequential search	p. 298
How to perform a binary search	p. 300
How to search a two-level table using indexes	p. 302
How to work with variable-length tables	p. 304
How to define a variable-length table	p. 304
How to load a variable-length table	p. 306
How to search a variable-length table	p. 306
Another technique for working with variable-length tables	p. 308
Other features for working with tables	p. 310
How to use the Perform Varying statement to vary more than one index or subscript	p. 310
How to use intrinsic functions with tables	p. 312
How to use copy members and subprograms
How to use copy members	p. 316
How to use the Copy statement	p. 316
Guidelines for using copy members	p. 318
How to use subprograms	p. 320
How to call a subprogram	p. 320
How to write a subprogram	p. 322
Another example of a calling program and subprogram	p. 324
Guidelines for using subprograms	p. 326
COBOL for working with files
Concepts and terms for working with disk files
Disk concepts and terms	p. 332
How data is stored on a disk drive	p. 332
How the data in a sector is read or written	p. 334
Blocked versus unblocked records	p. 336
Fixed-length versus variable-length records	p. 336
File organization concepts	p. 338
Sequential file organization	p. 338
Indexed file organization	p. 340
Indexed file organization with alternate indexes	p. 342
Relative file organization	p. 344
VSAM file organizations	p. 344
Typical programs that work with disk files	p. 346
Interactive programs	p. 346
Batch programs	p. 348
How to work with sequential files
COBOL for fixed-length records	p. 354
How to code Select and FD statements	p. 354
How to code Procedure Division statements	p. 356
How to work with file status codes	p. 358
A sequential update program	p. 360
The program specifications	p. 360
The test data and matching record logic	p. 362
The structure chart	p. 364
The COBOL code	p. 366
A sequential maintenance program	p. 372
The program specifications	p. 372
The test data and matching record logic	p. 374
The structure chart	p. 376
The COBOL code	p. 378
Special considerations for sequential update and maintenance programs	p. 386
Error processing for I/O operations	p. 386
Testing and debugging	p. 388
Design alternatives	p. 390
COBOL for variable-length records	p. 392
How to code FD statements	p. 392
How to write to a file that contains record types with different lengths	p. 394
How to process a file that contains record types with different lengths	p. 396
How to write records with a varying number of segments	p. 398
How to process records with a varying number of segments	p. 400
How to work with indexed files
COBOL for indexed files	p. 404
How to code Select statements	p. 404
File status codes	p. 406
How to code the Open, Close, Read, Write, and Rewrite statements	p. 408
How to code the Start statement	p. 410
How to code the Delete statement	p. 410
A sequential file creation program	p. 412
The program specifications	p. 412
The structure chart	p. 412
The COBOL code	p. 414
A random maintenance program	p. 418
The program specifications	p. 418
The structure chart	p. 420
The COBOL code	p. 422
How to work with alternate indexes	p. 430
How to code Select statements	p. 430
How to code Start and Read statements	p. 432
How to process an alternate index sequentially	p. 434
How to process an alternate index randomly	p. 436
Other processing techniques	p. 438
How to use dynamic processing	p. 438
How to use skip-sequential processing	p. 440
How to work with relative files
COBOL for relative files	p. 444
How to code Select statements	p. 444
How to code I/O statements	p. 446
How to process relative files	p. 448
Sequential processing	p. 448
Random processing	p. 450
How to use the sort/merge feature
Concepts for sorting and merging	p. 454
Sorting concepts	p. 454
Merging concepts	p. 456
Why COBOL sorts and merges improve efficiency	p. 458
COBOL for sorting	p. 460
How to code Select and SD statements	p. 460
How to code the Sort statement	p. 462
How to code the Release statement	p. 464
How to code the Return statement	p. 464
An edit-sort-and-update program	p. 466
The program specifications	p. 466
The structure chart	p. 468
The COBOL code	p. 470
Efficiency considerations	p. 472
COBOL for merging	p. 476
How to code the Merge statement	p. 476
How to use the Sort statement to merge files	p. 478
How to merge files using JCL	p. 478
Two more sort/merge considerations	p. 480
IBM special registers	p. 480
The FASTSRT compiler option	p. 480
The IBM mainframe environment for COBOL
Introduction to IBM mainframes
IBM mainframe processors	p. 486
The basic architecture of a processor	p. 486
The history of the System 360/370 family of processors	p. 488
Input/output devices for IBM mainframes	p. 490
Terminal display devices	p. 492
Direct access storage devices	p. 494
Printer devices	p. 494
Magnetic tape and optical disk devices	p. 494
The basic features of a mainframe operating system	p. 496
Virtual storage	p. 496
Multiprogramming	p. 496
Spooling	p. 498
Batch processing	p. 500
Time sharing	p. 502
Operating systems for IBM mainframes	p. 504
The OS family of operating systems	p. 504
Other IBM mainframe operating systems	p. 504
Features of the OS/390 and z/OS operating systems	p. 506
OS/390 and z/OS subsystems and facilities	p. 508
How to compile and test programs on an IBM mainframe
An introduction to program development on a mainframe	p. 512
How a COBOL program is compiled, link-edited, and executed on a mainframe	p. 512
A general procedure for developing a COBOL program on a mainframe	p. 512
How to create a source program using ISPF	p. 514
Basic skills for working with ISPF	p. 514
How to create a partitioned data set	p. 516
How to start an edit session	p. 518
How to work in the edit data display	p. 520
How to use line commands and primary commands	p. 522
How to terminate an edit session	p. 522
How to compile, link-edit, and execute a program	p. 524
An introduction to jobs and Job Control Language	p. 524
The cataloged procedures for COBOL program development	p. 526
How to use the compile-link-and-go procedure	p. 528
How to execute an existing program	p. 530
How to create a sequential data set	p. 532
How to use SDSF to work with jobs and job output	p. 534
Basic skills for working with SDSF	p. 534
How to work with jobs	p. 536
How to use SDSF to work with jobs and job output (continued)
How to work with job output	p. 538
How to display job output	p. 540
How to handle compile-time and run-time error messages	p. 542
How to handle compile-time error messages	p. 542
How to handle run-time error messages	p. 544
How to use Access Method Services to work with VSAM files
How VSAM manages data sets	p. 548
The Integrated Catalog Facility (ICF)	p. 548
Control intervals and control areas	p. 550
Free space and record additions for a KSDS	p. 552
How a record in a KSDS is randomly accessed by primary key	p. 554
How alternate indexes work	p. 554
Introduction to Access Method Services	p. 556
Some commonly used AMS commands	p. 556
The JCL requirements for using AMS commands	p. 558
The syntax requirements for AMS commands	p. 558
How to use the Define Cluster command to define a data set	p. 560
Parameters that identify a data set	p. 562
Parameters that describe the data set's characteristics	p. 564
Parameters that allocate space to the data set	p. 566
Other Define Cluster parameters	p. 568
How to use the Listcat command to list catalog information	p. 570
How to identify the entries you want to list	p. 572
How to limit the amount of information that's listed for each entry	p. 572
How to use AMS commands to print, copy, and delete data sets	p. 574
How to use the Print command to print a data set	p. 574
How to use the Repro command to copy a data set	p. 576
How to use the Delete command to delete a data set	p. 578
How to define and build an alternate index	p. 580
How to use the Define Alternateindex command	p. 580
How to use the Define Path command	p. 582
How to use the Bldindex command	p. 584
How to use CICS to develop interactive programs
Program development concepts and techniques	p. 588
How application programs use CICS services	p. 588
How pseudo-conversational programming works	p. 590
How to develop CICS programs	p. 592
The Execute Interface Block and the Dfhaid copy member	p. 594
A CICS inquiry program	p. 596
The program specifications	p. 596
The BMS mapset	p. 598
The symbolic map	p. 602
The structure chart	p. 606
The COBOL listing	p. 608
Introduction to CICS web programming	p. 616
The benefits of using CICS for web applications	p. 616
How to connect to CICS through the Internet	p. 616
Three techniques for accessing CICS programs	p. 618
How the CICS Transaction Gateway works	p. 620
How the 3270 Bridge exit works	p. 622
How to use DB2 to develop database programs
DB2 and the relational database model	p. 626
How a relational database is organized	p. 626
How the tables in a relational database are related	p. 628
How to use SQL to work with a DB2 database	p. 630
Introduction to Structured Query Language	p. 630
How to retrieve data from a single table	p. 632
How to join data from two or more tables	p. 634
How to create and work with result tables using embedded SQL	p. 636
A DB2 inquiry program	p. 638
The interactive screen	p. 638
The DCLGEN output	p. 640
The structure chart	p. 642
The COBOL listing	p. 644
How to develop a COBOL program that accesses DB2 data	p. 650
How to become an effective maintenance programmer
Statements and features you should be aware of	p. 654
Perform Thru and Go To statements	p. 654
Go To Depending statements	p. 656
Section names in the Procedure Division	p. 658
Qualification and the Move, Add, and Subtract Corresponding statements	p. 660
Declarative sections	p. 662
The basic skills for maintaining programs	p. 664
A structured procedure for maintaining a program	p. 664
What to change and where to change it	p. 666
How to document the changes in the source code	p. 668
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