Selecting versions of CICS programs and tables

A CICS® program is usually made up from a group of related CICS functional modules, one example of which is the terminal control program. For most CICS programs you can only have one version, which is supplied with CICS. However, for some CICS programs you can create more than one version; for example, with different service levels. To select a particular version of a program, you can include the load library containing that version in the CICS startup JCL. For the basic mapping support (BMS) suite, however, you can select from different versions, by explicitly selecting the level of function needed.

You can also specify that a program is not needed (see Excluding unwanted programs for details).

You can use these methods only for the programs referred to in this topic and in Excluding unwanted programs, by coding system initialization parameters.

Using an explicit level of function to select programs

You use an explicit level of function to select the BMS suite of programs. When you specify your BMS requirement on the system initialization parameter BMS, you can select one of three versions. The BMS level of function is selected by the parameter options MINIMUM, STANDARD, or FULL, from which the system initialization program loads the set of programs you require.

Excluding unwanted programs

The three ways of excluding programs that are not required are by specifying:

  1. programname=NO
  2. tablename=NO
  3. function=NO

Specifying programname=NO

If you code programnamesystem initialization parameter=NO as a , (for example, DIP=NO), you exclude the named management program at CICS system initialization.

The programs that you can exclude by coding programname:=NO are

Note:
In the case of DIP, you get a dummy version of the management program, which is supplied on the distribution tape with a suffix of DY.

Specifying tablename=NO for the programs control table

Not all of the CICS programs have a programname parameter in the SIT. Ansystem initialization parameter alternative method is to code NO on the for the associated table. This has the same effect as coding NO against a program name parameter, and the associated CICS program is excluded at system initialization, either by loading a dummy program, or by some other technique.

The system recovery table (SRT) can be used in this way, and the associated system recovery program (SRP) will be excluded.

The dummy TCT, DFHTCTDY

There is a special case where you can also specify tablename=NO, but this does not load a dummy terminal control program. You specify TCT=NO when you are using resource definition online, and all your terminal resource definitions are in the CSD.

When you specify TCT=NO, CICS loads a dummy TCT named DFHTCTDY. A pregeneratedCICSTS31.CICS dummy table of this name is supplied in .SDFHLOAD, and the sourceCICSTS31.CICS statements of DFHTCTDY are supplied in .SDFHSAMP. If you specify TCT=NO, a generated table of this name must be available in a library of the DFHRPL concatenation when you start CICS.

The dummy TCT provides only the CICS and VTAM® control blocks that you need if you are using VTAM terminals and using the CSD for storing terminal definitions. You define your VTAM terminals using the RDO transaction, CEDA, or the DEFINE command of the CSD batch utility program, DFHCSDUP.

Specifying function=NO

If you code function=NO as a system initialization parameter (for example, XRF=NO), you exclude the management program associated with the named function at CICS system initialization.

You can exclude intersystem communication (ISC), the 3270 print-request facility, the system spooling interface, or the extended recovery facility (XRF), in this way.

Related tasks
Specifying CICS system initialization parameters
Specifying DFHSIT macro parameters
The default system initialization table
Assembling the SIT
Processing system initialization parameters
Related concepts
System initialization parameters for open TCBs
Related reference
The system initialization parameter descriptions
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