Variable access routine

The language processor provides an interface whereby called commands and programs can easily access and manipulate the current generation of REXX variables. Any variable can be inspected, set, or dropped; if required, all active variables can be inspected in turn. Names are checked for validity by the interface code, and optionally substitution into compound symbols is carried out according to normal REXX rules. Certain other information about the program that is running is also made available through the interface.

TSO/E REXX provides two variable access routines you can call to access and manipulate REXX exec variables:

IRXEXCOM
IKJCT441

The IRXEXCOM variable access routine lets unauthorized commands and programs access and manipulate REXX variables. IRXEXCOM can be used in both the TSO/E and non-TSO/E address spaces. IRXEXCOM can be used only if a REXX exec has been enabled for variable access in the language processor environment. That is, an exec must have been invoked, but is not currently being processed. For example, you can invoke an exec that calls a routine and the routine can then invoke IRXEXCOM. When the routine calls IRXEXCOM, the REXX exec is enabled for variable access, but it is not being processed. If a routine calls IRXEXCOM and an exec has not been enabled, IRXEXCOM returns with an error.

Tip: To permit FORTRAN programs to call IRXEXCOM, TSO/E provides an alternate entry point for the IRXEXCOM routine. The alternate entry point name is IRXEXC.

A program can access IRXEXCOM using either the CALL or LINK macro instructions, specifying IRXEXCOM as the entry point name. You can obtain the address of the IRXEXCOM routine from the REXX vector of external entry points. Format of the REXX vector of external entry points describes the vector.

If a program uses IRXEXCOM, it must create a parameter list and pass the address of the parameter list in register 1.

Environment Customization Considerations: If you use the IRXINIT initialization routine to initialize language processor environments, you can specify the environment in which you want IRXEXCOM to run. On the call to IRXEXCOM, you can optionally specify the address of the environment block for the environment in either the parameter list or in register 0.

For more information about specifying environments and how routines determine the environment in which to run, see Specifying the address of the environment block.

The IKJCT441 routine lets authorized and unauthorized commands and programs access REXX variables. IKJCT441 can be used in the TSO/E address space only. You can use IKJCT441 to access REXX or CLIST variables depending on whether the program that calls IKJCT441 was called by a REXX exec or a CLIST. z/OS TSO/E Programming Services describes IKJCT441.