In the parameter block, the MODNAMET field points to the module name table (see Characteristics of a Language Processor Environment).

Table 1 shows the format of the module name table. Each field is described in detail following the table. The end of the table is indicated by X'FFFFFFFFFFFFFFFF'. TSO/E provides a mapping macro IRXMODNT for the module name table. The mapping macro is in SYS1.MACLIB.

Each field in the module name table is described below. You can specify some fields for any type of language processor environment. You can use other fields only for environments that are integrated into TSO/E or for environments that are not integrated into TSO/E. The description of each field below indicates the type of environment for which you can use the field. Relationship of fields in module name table to types of environments summarizes the fields in the module name table and the environments for which you can specify each field.

INDD

Specifies the name of the DD from which the PARSE EXTERNAL instruction reads input data (in a language processor environment that is not integrated into TSO/E). The system default is SYSTSIN.

If the environment is integrated into TSO/E (the TSOFL flag is on), the system ignores any value you specify for INDD. In TSO/E foreground, TSO/E uses the terminal. In the background, TSO/E uses the input stream, which is SYSTSIN.

OUTDD

Specifies the name of the DD to which data is written for a SAY instruction, for REXX error messages, or when tracing is started (in a language processor environment that is not integrated into TSO/E). The system default is SYSTSPRT.

If the environment is integrated into TSO/E (the TSOFL flag is on), the system ignores any value you specify for OUTDD. In TSO/E foreground, TSO/E uses the terminal. In the background, TSO/E uses the output stream, which is SYSTSPRT.

LOADDD

Specifies the name of the DD from which REXX execs are loaded. The default is SYSEXEC. You can specify a ddname in any type of language processor environment (integrated or not integrated into TSO/E).

In TSO/E, you can store REXX execs in data sets that are allocated to SYSEXEC or SYSPROC. If you store an exec in a data set that is allocated to SYSPROC, the exec must start with a comment containing the characters REXX within the first line (line 1). This is required to distinguish REXX execs from CLISTs that are also stored in SYSPROC.

In data sets that are allocated to SYSEXEC, you can store REXX execs only, not CLISTs. If you store an exec in SYSEXEC, the exec does not need to start with a comment containing the characters "REXX". However, it is suggested that you start all REXX programs with a comment regardless of where you store them. SYSEXEC is useful for REXX execs that follow the SAA Procedures Language standards and that will be used on other SAA environments.

The NOLOADDD flag (see Flags and corresponding masks) controls whether the system searches the DD specified in the LOADDD field.

• If the NOLOADDD flag is off, the system searches the DD specified in the LOADDD field. If the language processor environment is integrated into TSO/E and the exec is not found, the system then searches SYSPROC.
• If the NOLOADDD flag is on, the system does not search the DD specified in the LOADDD field. However, if the language processor environment is integrated into TSO/E, the system searches SYSPROC.

In the default parameters module that is provided for TSO/E (IRXTSPRM), the NOLOADDD mask and flag settings indicate that SYSEXEC is searched before SYSPROC. (Note that before TSO/E 2.3, the default settings indicated that SYSPROC only was searched). In the default parameters module for ISPF (IRXISPRM), the defaults indicate that the environment inherits the values from the previous environment, which is the environment initialized for TSO/E. By default, the system searches the ddname specified in the LOADDD field (SYSEXEC). To use SYSPROC exclusively, you can provide your own parameters module or use the EXECUTIL SEARCHDD command. For more information, see Using SYSPROC and SYSEXEC for REXX execs.

IOROUT

Specifies the name of the routine that is called for input and output operations. The routine is called for:

• The PARSE EXTERNAL, SAY, and TRACE instructions when the exec is running in an environment that is not integrated into TSO/E
• The PULL instruction when the exec is running in an environment that is not integrated into TSO/E and the data stack is empty
• Requests from the EXECIO command
• Issuing REXX error messages

You can specify an I/O replaceable routine only in language processor environments that are not integrated into TSO/E. For more information about the replaceable routine, see Input/Output routine.

EXROUT

Specifies the name of the routine that is called to load and free a REXX exec. The routine returns the structure that is described in The in-storage control block (INSTBLK). The specified routine is called to load and free this structure.

You can specify an exec load replaceable routine only in language processor environments that are not integrated into TSO/E. For more information about the replaceable routine, see Exec load routine.

GETFREER

Specifies the name of the routine that is called when storage is to be obtained or freed. If this field is blank, TSO/E storage routines handle storage requests and use the GETMAIN and FREEMAIN macros when larger amounts of storage must be handled.

You can specify a storage management replaceable routine only in language processor environments that are not integrated into TSO/E. For more information about the replaceable routine, see Storage management routine.

EXECINIT

Specifies the name of an exit routine that gets control after the system initializes the REXX variable pool for a REXX exec, but before the language processor processes the first clause in the exec. The exit differs from other standard TSO/E exits. The exit does not have a fixed name. You provide the exit and specify the routine's name in the EXECINIT field. REXX exit routines describes the exec initialization exit.

You can provide an exec initialization exit in any type of language processor environment (integrated or not integrated into TSO/E).

ATTNROUT

Specifies the name of an exit routine that is invoked if a REXX exec is processing in the TSO/E address space (in an environment that is integrated into TSO/E), and an attention interruption occurs. The attention handling exit differs from other standard TSO/E exits. The exit does not have a fixed name. You provide the exit and specify the routine's name in the ATTNROUT field. REXX exit routines describes the attention handling exit.

You can provide an attention handling exit only in a language processor environment that is integrated into TSO/E.

STACKRT

Specifies the name of the routine that the system calls to handle all data stack requests.

You can specify a data stack replaceable routine only in language processor environments that are not integrated into TSO/E. For more information about the replaceable routine, see Data stack routine.

IRXEXECX

Specifies the name of an exit routine that is invoked whenever the IRXEXEC routine is called to run an exec. You can use the exit to check the parameters specified on the call to IRXEXEC, change the parameters, or decide whether IRXEXEC processing should continue.

The exit differs from other standard TSO/E exits. The exit does not have a fixed name. You provide the exit and specify the routine's name in the IRXEXECX field.

You can provide an exit for the IRXEXEC routine in any type of language processor environment (integrated or not integrated into TSO/E). For more information about the exit, see REXX exit routines.

IDROUT

Specifies the name of a replaceable routine that the system calls to obtain the user ID. The USERID built-in function returns the result that the replaceable routine obtains.

You can specify a user ID replaceable routine only in language processor environments that are not integrated into TSO/E. For more information about the replaceable routine, see User ID routine.

MSGIDRT

Specifies the name of a replaceable routine that determines whether the system should display the message identifier (message ID) with a REXX error message.

You can specify a message identifier replaceable routine only in language processor environments that are not integrated into TSO/E. For more information about the replaceable routine, see Message identifier routine.

EXECTERM

Specifies the name of an exit routine that gets control after the language processor processes a REXX exec, but before the system terminates the REXX variable pool. The exit differs from other standard TSO/E exits. The exit does not have a fixed name. You provide the exit and specify the routine's name in the EXECTERM field. REXX exit routines describes the exit in more detail.

You can provide an exec termination exit in any type of language processor environment (integrated or not integrated into TSO/E).

X'FFFFFFFFFFFFFFFF'

The end of the module name table must be indicated by X'FFFFFFFFFFFFFFFF'.