Designing and Programming CICS Applications

Chapter 5. Programming the COBOL Business Logic

In this chapter:

• Writing CICS Programs in COBOL

• Handling Files

• Saving Data: Using a Scratchpad Facility

• Controlling Programs

• Abending a Transaction

• Queuing Facilities: Temporary Storage and Transient Data

• Handling Errors

• What’s Next…

You are now ready to write the COBOL code of the sample application. This chapter describes:

• Writing CICS programs in COBOL

• Dealing with file handling in CICS programs

• Saving data using a scratchpad facility

• Moving control from one program to another in the application

• The queuing facilities of temporary storage and transient data

• Handing errors in you programs

Writing CICS Programs in COBOL

The source programs are listed on the CD-ROM that is packaged with this book. They include a step-by-step description of what the code does. This chapter is about programming the business logic component, other services including Basic Mapping Support (BMS), the CICS supplied services for formatting a green screen, are described in “Programming the 3270 Presentation Logic Component” in Chapter 11.

Invoking CICS Services

When you need a CICS system service—for example, when reading a record from a file—you just include a CICS command in your code. CICS commands look like:

EXEC CICS function
          [option (argument)][option ...]... [terminator]

The options for this command are:

Terminator

The terminator is language dependent. For COBOL, the reserved word is either END-EXEC or a period (full stop). The full stop option should be avoided since it ...