D725 Advanced Topics in COBOL (Enterprise, z/OS)

Advanced Topics in COBOL (Enterprise, z/OS) - Topical Outline

Day One

Introduction to Subroutines

Invoking Subroutines - CALL

Leaving a CALLed program

Passing Arguments and Receiving Parameters

Computer Exercise: A Mainline and Subroutines

Additional Subroutine Topics

Static vs. Dynamic CALLS

CALL ... ON OVERFLOW / EXCEPTION

CANCEL

Passing Arguments BY VALUE

How arguments are passed

How parameters are received

Returning values: the RETURNING phrase

Shared Data: the EXTERNAL Attribute

Computer Exercise: External Subroutines and Shared Data

Nested Programs

Nested Programs - The Concept

Nested Program Structures

The Uses of Nested Programs

The INITIAL Attribute

Computer Exercise: Nested Programs

Additional Subroutine Capabilities - Optional

ENTRY Points

Local-storage

Recursive programs

Table Handling

Tables and subscripts

Loading a Table From a File

Looking Up an Element in a Table

Computer Exercise: Build and Print a Table

Day Two

Table Handling, II

Sorting a Table

Computer Exercise: Table Sorting

Table Handling, III

Variable Length Tables

Two-Dimensional Tables

Initializing Tables

VALUE clauses, REDEFINES and INITIALIZE

Loops and I/O

PERFORM ... VARYING

Computer Exercise: Two Dimensional Tables

Indexing

Index-names and Index Data Items

SET, SEARCH, SEARCH ALL

Computer Exercise: Using Indexes and SEARCH

Intrinsic Functions and Tables

Concepts and Syntax

The ALL subscript

Day Three

Variable Length Records

Defining

Processing

Computer Exercise: Reading a File With Variable Length Records

Introduction to String Handling In COBOL

Hex Notation

Reference Modification

LENGTH OF special register (IBM extension)

LENGTH intrinsic function

INSPECT

Computer Exercise: Analyzing Strings

More String Handling in COBOL

STRING

UNSTRING

Computer Exercise: More String Handling

COBOL SORT Facility (Optional)

Sort files

The SORT verb

Sort control statements

MERGE

Computer Exercise: COBOL SORT