CICS Reviewer Part 2

What is the function of the EXEC CICS HANDLE CONDITION command?
To specify the paragraph or program label to which control is to be passed if the "handle condition" occurs.

How many conditions can you include in a single HANDLE CONDITION command?
No more than 16 in a single handle condition. If you need more, then you must code another HANDLE CONDITION command.

What is the EXEC CICS HANDLE ABEND?
It allows the establishing of an exit so cleanup processing can be done in the event of abnormal task termination.

What is the difference between EXEC CICS HANDLE CONDITION and an EXEC CICS IGNORE command?
A HANDLE CONDITION command creates a "go-to" environment. An IGNORE command does not create a go-to environment; instead, it gives control back to the next sequential instruction following the command causing the condition. They are opposites.

What happens when a CICS command contains the NOHANDLE option?
No action is going to be taken for any exceptional condition occuring the execution of this command. The abnormal condition that occurred will be ignored even if an EXEC CICS HANDLE condition exist. It has the same effect as the EXEC CICS IGNORE condition except that it will not cancel the previous HANDLE CONDITION for any command.

When a task suspends all the handle conditions via the PUSH command, how does the task reactivate all the handle conditions?
By coding an EXEC CICS POP HANDLE command.

Explain re-entrancy as applies to CICS.
Reentrant program is a program which does not modify itself so that it can reenter to itself and continue processing after an interruption by the operating system which, during the interruption, executes other OS tasks including OS tasks of the same program. It is also called "reenterable" program or "serially reusable" program.

A quasi-reentrant program is a reentrant program under the CICS environment. That is, the quasi-reentrant program is a CICS program which does not modify itself. That way it can reenter to iself and continue processing after an interruption by CICS which, during the interruption, executes other tasks including CICS tasks of the same program. In order to maintain the quasi-reentrancy, a CICS application program must follow the following convention:

Constants in Working Storage: the quasi-reentrant program defines only constants in its ordinary data area (e.g. working storage section). These constant will never be modified and shared by the tasks.

Variable in the Dynamic Working Storage: The quasi-reentrant program acquires a unique storage are (called Dynamic Working Storage - DWS) dynamically for each task by issuing the CICS macro equivalent GETMAIN. All variables will be placed in this DWS for each task. All counters would have to be initialized after the DWS has been acquired.

Restriction on Program Alteration: The program must not alter the program itself. If it alters a CICS macro or command, it must restore the alteration before the subsequent CICS macro or command.

CICS Reviewer Part 3 is continued here.