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

Other Advanced Topics

• Null-terminated strings
• Pointers
• Address Of Special Register
• Procedure-pointers
• Function-pointers
• Dynamic file allocation