CICS for Applications Programmers

Prerequisites:

Some coding experience in Cobol, PL/1 or Assembler. The course does not seek to teach delegates their respective programming language but concentrates on the CICS Commands.

Course Description:

This course is suitable for Programmers who will be coding or maintaining CICS applications and Programmers who wish to have CICS coding expertise. Project managers, Systems Designers and Programmers working in CICS will also benefit.

After taking this course, students will:

- Be able to code programs with embedded CICS Commands.
- Understand the concepts of on-line processing through CICS.
- Understand the fundamentals of Pseudo-conversational Programming and the use of COMMAREAs.
- Be able to code and have a working knowledge of Basic Mapping Support (BMS).
- Understand and code CICS Commands to access VSAM files in CICS.
- Know how to use CICS facilities such as File Control, Temporary Storage, Transient Data and Interval Control.
- Understand the requirements for Multitasking and Reentrancy.
- Know how to code efficient CICS programs.

This course includes the following modules:

Introduction to CICS Concepts

• We discuss on-line processing, what CICS is and how it fits into the DP environment.
• Basic terminology is explained including Psuedo-conversational programming (what it is, how we code it).
• Transaction and program concepts are introduced.
• CICS command format syntax is covered in detail.

Exception Processing

• HANDLE CONDITION
• Command
• Options
• Techniques.
• Emphasis is on using structured programming techniques in CICS.

Terminal Communications

• Telecommunications concepts
• VTAM
• 3270 processing fundamentals.
• Data transmission via maps
• Basic Mapping Support (BMS) to build maps is introduced.

Basic Mapping Support

• Mapset and DSECT concepts explained.
• Defining a Mapset, the DFHMSD macro, with its options and defaults.
• Difining a Map, the DFHMDI macro, with its options and defaults.
• Defining a Field, the DFHMDF macro, with its options and defaults.

Map Commands

• The SEND MAP command to output the BMS map with its functions.
• The MAPONLY/DATAONLY concepts to reduce transmission costs.
• The RECEIVE MAP command to input data Pseudo-conversationally.
• DSECT copybook fields are explained in detail. The length, attribute and erased flags along with the input and output data fields are discussed. Extended attributes (colour, highlighting etc) are presented.

File Operations

• VSAM file concepts are introduced. CICS/VSAM interaction is explained.
• KSDS, ESDS, REDS file commands (READ, WRITE etc) and their options.
• Record Level locking and simultaneous updating problems are explained.
• Generic DELETE pitfalls are shown.
• BROWSE functions (forward and backward) are presented.

Temporary Storage

• An overview of Temporary Storage, which will emphasise the scratched type concept, is presented along with examples.
• The commands and problems with suggested solutions are presented.
• Future changes in Temporary Storage are explained.

CICS Transactions

• An overview of the CICS supplied application transactions useful to the programmer is given.
• CEMT is explained, with its dangers.
• CEDF is used in a hands-on environment.
• CECI concepts are shown.

Summary

• A review of the concepts and commands is given.
• Sample programs are walked through.
• The future of CICS is discussed.
• DB2 and VSAM file concepts are addressed in the workshops.