Coding COBOL programs to run under CICS
To code a program to run under CICS®, code CICS commands
in the PROCEDURE DIVISION
by using the EXEC
CICS
command format.
About this task
EXEC CICS command-name command-options
END-EXEC
CICS commands
have the basic format shown above. Within EXEC
commands,
use the space as a word separator; do not use a comma or a semicolon.
Do not code COBOL statements within EXEC CICS
commands.
-
Db2® files that will interoperate with TXSeries or CICS TX must be created with
FILEMODE(SMALL)
in effect. - Object-oriented programming and interoperability with Java™ are not supported.
- The source program must not contain any nested programs.
- COBOL programs that will run under TXSeries or CICS TX must be 32 bit.
Do not use EXEC
, CICS
, or END-EXEC
as
variable names, and do not use user-specified parameters to the main
program. In addition, it is recommended that you not use any of the
following COBOL language elements:
FILE-CONTROL
entry in theENVIRONMENT DIVISION
FILE SECTION
in theDATA DIVISION
USE
declaratives, exceptUSE FOR DEBUGGING
The following COBOL statements are also not recommended for use in a CICS environment:
ACCEPT
format 1CLOSE
DELETE
DISPLAY UPON CONSOLE
,DISPLAY UPON SYSPUNCH
MERGE
OPEN
READ
REWRITE
SORT
START
STOP
literalWRITE
Apart from some
forms of the ACCEPT
statement, mainframe CICS does not support any of the
COBOL language elements in the preceding list. If you use any of those
elements, be aware of the following limitations:
- The program is not completely portable to the mainframe CICS environment.
- In the case of a CICS failure, a backout (restoring the resources that are associated with the failed task) for resources that were updated by using the above statements will not be possible.