Functions you can specify for parameter 1

The functions that can be specified in parameter 1 are described below.

INIT

The routine performs any initialization that is required. During the initialization of a language processor environment, the system calls the exec load routine to initialize load processing.

LOAD

The routine loads the exec specified in the exec block from the ddname specified in the exec block. Format of the exec block describes the exec block.

The routine returns the address of the in-storage control block (parameter 3) that represents the loaded exec. Format of the in-storage control block shows the format of the in-storage control block.

Note: The TSO/E IRXLOAD routine reuses an existing copy of a previously loaded exec if one already exists in storage, and if it appears that the exec did not change since the exec was originally loaded. However, if the CLOSEXFL flag is on, indicating the SYSEXEC data set should be closed after each exec is loaded from SYSEXEC, IRXLOAD will not reuse a previously loaded exec copy to satisfy a load request. Instead, each load request results in a new copy of the exec being read into storage. For more information about the CLOSEXFL flag, see Flags and corresponding masks.

TSOLOAD

The routine loads the exec specified in the exec block from the current list of ddnames that TSO/E is using to search for REXX execs. For example, the routine may search load libraries, any exec libraries as defined by the TSO/E ALTLIB command, and SYSEXEC and SYSPROC. See Search order for a description of the complete search order.

You can use the TSOLOAD function only in the TSO/E address space in a language processor environment that is integrated into TSO/E. TSOLOAD requires an environment that is integrated into TSO/E because TSOLOAD requests that the exec load routine use the current TSO/E search order to locate the exec.

The TSOLOAD function is intended for use if you call the system-supplied exec load routine (IRXLOAD) in TSO/E. TSOLOAD gives you the flexibility to search more than one DD to locate a REXX exec compared to the LOAD function, which only searches the DD specified in the exec block. You can also use the TSOLOAD function if you write your own exec load routine and then call your routine from application programs running in TSO/E.

TSOLOAD is not intended for language processor environments that are not integrated into TSO/E. Therefore, if you provide an exec load routine to replace the system- supplied exec load routine in the module name table, your routine that replaces the system routine need not handle the TSOLOAD request. This is because you can replace the system-supplied exec load routine only in environments that are not integrated into TSO/E.

For the TSOLOAD function, the exec load routine returns the:

DD from which the exec was loaded. The routine returns the ddname in the exec block (at offset +24) that you provide on the call.
Address of the in-storage control block in parameter 3 of the parameter list. The control block represents the loaded exec.

FREE

The routine frees the exec represented by the in-storage control block that is pointed to by parameter 3.

Rule: If a user written load routine calls IRXLOAD to load an exec, the user written load routine must also call IRXLOAD to free the exec. If TSO/E REXX loads an exec, it also frees the exec. For information about the IRXEXEC routine, see The IRXEXEC routine.

STATUS

The routine determines whether the exec specified in the exec block is currently loaded in storage from the ddname specified in the exec block. If the exec is loaded, the routine returns the address of the in-storage control block in parameter 3. The address that the routine returns is the same address that was returned for the LOAD function when the routine originally loaded the exec into storage.

TERM

The routine performs any cleanup before termination of the language processor environment. When the last language processor environment under the task that originally opened the DD terminates, all files associated with the environment are closed. In TSO/E REXX, when terminating the last language processor environment under a task, IRXLOAD frees any execs that were loaded by any language processor environment under the task but which were not yet freed.

CLOSEDD

The routine closes the data set specified in the exec block, it does not free any execs that have been loaded from this data set.

The CLOSEDD function allows you to free and reallocate data sets. Only data sets that were opened on the current task can be closed.