TSO/E provides default values in three parameters modules (load modules) for initializing language processor environments in non-TSO/E, TSO/E, and ISPF. In most cases, your installation probably need not change the default values. However, if you want to change one or more parameter values, you can provide your own load module that contains your values.

You can also call the initialization routine, IRXINIT, to initialize a new environment. On the call, you can pass the parameters whose values you want to be different from the previous environment. If you do not specifically pass a parameter, IRXINIT uses the value defined in the previous environment. See Initialization routine - IRXINIT for more information.

This topic describes how to create a load module containing parameter values for initializing an environment. You should also refer to Characteristics of a Language Processor Environment for information about the format of the parameters module.

When you write the code, be sure to include the correct default values for any parameters you are not changing. For example, suppose you are adding several function packages to the IRXISPRM module for ISPF. In addition to coding the function package table, you must also provide all of the other fields in the parameters module and their default values. Values provided in the three default parameters modules shows the default parameter values for IRXPARMS, IRXTSPRM, and IRXISPRM.

After you create the code, you must assemble the code and then link- edit the object code. The output is a member of a partitioned data set. The member name must be either IRXPARMS, IRXTSPRM, or IRXISPRM depending on the load module you are providing. You must then place the data set with the IRXPARMS, IRXTSPRM, or IRXISPRM member in the search sequence for an MVS LOAD macro. The parameters modules that TSO/E provides are in the LPALIB, so you could place your data set in a logon STEPLIB, a JOBLIB, or in linklist.

If you provide an IRXPARMS load module, your module may contain parameter values that cannot be used in language processor environments that are integrated into TSO/E. When IRXINIT initializes an environment for TSO/E, IRXINIT uses the IRXTSPRM parameters module. However, if a parameter value in IRXTSPRM is null, IRXINIT uses the value from the IRXPARMS module. Therefore, if you provide your own IRXPARMS load module that contains parameters that cannot be used in TSO/E, you must place the data set in either a STEPLIB or JOBLIB that is not searched by the TSO/E session. For more information about the values you can specify for different types of environments, see Specifying values for different environments.

The new values you specify in your own load module are not available until the current language processor environment is terminated and a new environment is initialized. For example, if you provide a load module for TSO/E (IRXTSPRM), you must log on TSO/E again.