Familiarize yourself with terms that have special meanings
in CICS®.
- Transaction
- A unit of processing, consisting of one or more programs.
- Task
- The processing of a transaction for a program user.
- Conversational
- The CICS term for running
a program in nonsegmented mode. A conversational program consists
of a sequence of alternating entries and responses between a user
and the program. File and database position and locks, and storage
resources are held across the terminal I/O operation.
- Pseudoconversational
- The CICS term for running
a program in segmented mode. A pseudoconversational program consists
of a series of single CICS tasks
designed to appear to the user as a continuous conversation. File
and database position and locks, and storage resources are released
across the terminal I/O operation. The program must save conversation
status before terminal output and restore it on terminal input.
- Communication area (COMMAREA)
- A data area used to transfer information between two programs
within a transaction or between two transactions from the same terminal.
When one program transfers to another, the COMMAREA can be any data
area the transferring program can access. The transferred-from program
can both pass data to that area and receive results in the area. The
data area is usually the working storage area of that program.
- Transaction Work Area (TWA)
- A fixed length storage area allocated for each transaction task
control area. Generated EGL programs use a 1024 byte section of the
TWA. The offset of the EGL section of bytes is controlled by the twaOffset build
descriptor option.
- Resource Definitions Online (RDO)
- Definitions of resources used or managed by the CICS system. Each definition is created by using
resource definition online (RDO). The following list shows the types
of definitions:
- TDQUEUE
- Used to define transient data destinations for the system.
- FILE
- Used to define files used by the system.
- PROGRAM
- Contains information about each program. The Rational® COBOL Runtime for z/Series programs,
generated COBOL programs, libraries, and servers, FormGroup online
print services programs, FormGroup format modules, and DataTables
must be defined. Alternatively, if you use the CICS autoinstall feature for programs you do
not need to create PROGRAM definitions.
- TRANSACTION
- Defines the transaction identifiers that can be entered by program
users. For each transaction, it also defines the related program that
starts the processing for the transaction.
- DB2CONN, DB2ENTRY, and DB2TRAN
- Describe the interface between the CICS region
and DB2®, including the association
of transaction codes with DB2 program
plans.
- PROFILE, TYPETERM, and TERMINAL
- Contain descriptions of terminals, their features, and operating
information.
- Temporary storage queue
- A CICS managed file for
storing intermediate results. Records in a temporary storage queue
can be accessed serially or by a relative record number. Descriptions
of the two types of temporary storage follow:
- Auxiliary
- A temporary storage queue that is stored on DASD. It can be recovered
and maintained from one CICS run
to the next.
- Main
- A temporary storage queue that exists in the CICS address space. It is not recoverable and
is not maintained from one CICS run
to the next.
- Transient data queue
- A CICS managed file that
is serially organized. Descriptions of the two types of transient
data queues follow:
- Extrapartition transient data queue
- A CICS managed serial file
in a system sequential data set or tape. The file can be an input
file or an output file but not both. Extrapartition queues are not
recoverable.
- Intrapartition transient data queue
- A transient data queue that is accessible to transactions running
in a CICS region. The queue
can be used for both input and output. On z/OS®, the queue is stored in a VSAM entry sequenced
data set. Intrapartition queues can be recovered.