This document contains general considerations that apply when running Natural in batch mode.
The following topics are covered:
Adabas datasets must be specified only in single-user mode. They are identical to those required for the execution of any normal application program using Adabas. See the relevant Adabas documentation for detailed information on Adabas datasets.
Sort datasets must be specified if a Natural program containing a
SORT statement is to be executed during the Natural session.
The requirements are identical to those for execution of a normal COBOL or PL/1 application program that invokes the operating system sort program and can vary according to the sort program in use.
Natural does not require the intermediate datasets SORTIN
and SORTOUT, but communicates with the sort program via the
E15 and E35 user-exit routine interfaces.
Note:
With Natural for CMS, subtasking is not supported.
With subtasking support, you can run multiple Natural batch mode sessions within one address space. This allows parallel processing within one address space, rather than executing subsequent job steps, and can increase throughput dramatically.
Typically, client/server applications and products would take advantage of this functionality, for example, the Natural remote procedure call. Multiple server subtasks can be started to communicate with remote clients.
If you wish to restart the Natural nucleus, it must be linked as a
reentrant module (linkage editor option RENT).
The Adabas link routine (ADALNK) must be generated with
reentrancy support.
You start a subtask by issuing a CALL statement from a Natural
program. The new Natural session ("subtask") is started with an
extended front-end parameter list. This list contains up to three parameter
sets:
dynamic Natural profile parameters,
startup parameters,
user parameters.
Variable names for standard I/O datasets (for example
CMPRINT) and other parameters for the batch mode interface startup
can be passed from the starting program in the startup parameter area. Standard
I/O datasets can be undefined or dummy datasets; they can be owned by one
session or shared by multiple sessions.
Furthermore, a CALL interface is provided for reading the
user parameter area with a Natural program.
The Natural batch mode interface without extended parameter list gets initial control from the operating system using standard linkage call. Register 1 points to an address with high-order bit on as the last address indicator. This address points to a halfword field containing the length of the following parameter area.
The extended parameter list contains up to three parameter addresses. This is indicated by the high-order bit in the last address which can be the first, second or third address. All parameter addresses point to a halfword field containing the parameter length of the following parameter area. Zero length indicates that there is no parameter area.
The first parameter area contains the dynamic profile parameters for the Natural session.
The second contains special startup parameters for the initialization of the batch mode interface.
The third contains a user parameter area which can be accessed during the Natural session.
When multiple batch mode Natural (sub)tasks are running in the same
region, by default these sessions access the very same Natural standard I/O
datasets (such as CMPRINT, CMSYNIN, etc), as there
are no Natural profile parameters available to set these file names. Also by
default the Natural system variables *INIT-ID and
*INIT-USER are identical because of their
definition for batch mode.
In order to provide unique standard I/O dataset names and unique IDs for Natural subtask sessions the startup parameters in the extented parameter list can be used to overwrite the Natural system defaults. The Startup Parameter area is a table of pairs of 8-character fields:
The first entry contains the 8-byte keyword to be replaced,
the second entry contains the 8-byte replacement value.
Keywords and replacement values must be padded with trailing blanks, if necessary.
The following keywords are valid:
CMHCOPY |
Permanent hardcopy destination |
CMSYNIN
|
Command input dataset name |
CMOBJIN
|
Object input dataset name |
CMPRINT
|
Standard output dataset name |
CMPRMIN
|
Dynamic parameter input dataset name |
CMPLOG
|
Dynamic parameter output dataset name |
CMTRACE
|
Trace output dataset name |
INITID
|
Job step name (system variable
*INIT-ID)
|
MSGCLASS
|
Spool class for dynamic allocation of CMPRINT and
CMTRACE (z/OS only)
|
NATRJE
|
Job submission dataset name (z/OS only) |
STEPLIB
|
Program load library name (see also profile parameter
LIBNAM,
Name of Load Library, z/OS only)
|
SUBPOOL
|
z/OS storage subpool (0 - 127, right justified) |
USERID
|
Initial user identification (system variable
*INIT-USER)
|
The usage of these entries is optional and no particular sequence is required. A blank value for a dataset means that this dataset is not available or is empty.
By default, all print output (that is, the one resulting from
CMPRINT, CMHCOPY, CMTRACE and
CMPLOG) is routed to SYSLST. An overwrite
specification for these files starting with SYS is considered a
z/VSE system number overwrite. Possible format is
SYSnnn where
nnn is a three-digit number in the range from
000 to 099; if you specify an invalid number
nnn, it is ignored.
The format of the user parameter area is free. It can be accessed from
any Natural program by a special CALL interface see
Accessing the
User Parameter Area.
The following call interface is supplied to be used by Natural programs to start a subtask in the same address space.
PGMNAME
|
Natural nucleus name getting control (mandatory). To restart with the same nucleus, an asterisk can be specified as the first character. The actual nucleus name is passed back in this field. |
NATPARML
|
Natural dynamic parameter area |
STRPARML
|
Startup parameter area |
USRPARML
|
User parameter area |
All parameter areas must start with the length of the following
parameters. The following example illustrates the usage of
CMTASK.
Example:
DEFINE DATA LOCAL 01 PGMNAME (A8) INIT <'*'> 01 PARM1 02 NATPARML (I2) INIT <30> 02 NATPARMS (A30) INIT <'INTENS=1,IM=D,STACK=MYPROG'> 01 PARM2 02 STRPARML (I2) INIT <32> 02 STRPARM1 (A16) INIT <'CMPRINT SYSPRINT'> 02 STRPARM2 (A16) INIT <'CMPRMIN MYPARMS'> 01 PARM3 02 USRPARML (I2) INIT <80> 02 USRPARMS (A80) INIT <'special user parameters'> END-DEFINE CALL 'CMTASK' PGMNAME NATPARML STRPARML USRPARML END
A sample program, ASYNBAT, can be found in library
SYSEXTP.
The user parameter area passed during startup can be read from any
Natural program with the following CALL statement:
CALL 'CMUPARM' USRPARML USRPARMS
USRPARML is the length (I2) of the
USRPARMS area (before the call) and the length of the data
returned (after the call). USRPARMS is the parameter data
area.
If the length of the data to be returned is greater than the area length, the data is truncated to the area length. The following return codes are possible:
0 |
Data successfully moved |
4
|
Data moved but truncated |
8 |
No data available |
12
|
Length value not positive |
16
|
Insufficient number of parameters |
A sample program, GETUPARM, can be found in library
SYSEXTP.
