Use ICEGENER instead of IEBGENER

You can achieve more efficient processing for applications set up to use the IEBGENER system utility by using DFSORT's ICEGENER facility. Qualifying IEBGENER jobs are processed by the equivalent (though not identical), but more efficient, DFSORT copy function. If, for any reason, the DFSORT copy function cannot be used (for example, if IEBGENER control statements are specified), control is automatically transferred to the IEBGENER system utility.

ICEGENER, like IEBGENER, will use an SDB=value parameter you supply using PARM='SDB=value', when appropriate. The valid SDB=value parameters are SDB=LARGE, SDB=YES, SDB=SMALL, SDB=INPUT and SDB=NO, as explained in OPTION control statement. If you supply an invalid SDB=value parameter, ICEGENER will transfer control to IEBGENER, which will terminate due to the invalid parameter. If you do not supply an SDB=value parameter, ICEGENER will use your site's DFSORT installation default for SDB, when appropriate (the IBM-supplied default is SDB=INPUT). If ICEGENER transfers control to IEBGENER, IEBGENER will use the SDB=value parameter you supply, if any, or its normal default for SDB.

ICEGENER will also recognize DFSORT parameters other than SDB=value you supply using PARM='parameter' that are valid on DFSORT's OPTION statement as explained in OPTION control statement. However, IEBGENER does not recognize any parameters other than the valid SDB=value forms, so if DFSORT must transfer control to IEBGENER, IEBGENER will not recognize DFSORT's parameters and will terminate. Likewise, if you supply a DFSORT parameter using PARM='parameter' that is not valid on DFSORT's OPTION statement, DFSORT will transfer control to IEBGENER and IEBGENER will terminate due to the invalid parameter.

For example, if you specify:

//S1 EXEC PGM=ICEGENER,PARM='SIZE=2000,MAINSIZE=2000K'

ICEGENER will accept SIZE=2000 and MAINSIZE=2000K as valid DFSORT OPTION parameters that specify an exact file size of 2000 records and a limit of 2000K bytes of storage, respectively. If DFSORT copy can be used, these parameters will be used. But if DFSORT must transfer control to IEBGENER, IEBGENER will terminate because it treats SIZE=2000 and MAINSIZE=2000K as invalid parameters.

As another example, if you specify:

//S2 EXEC PGM=ICEGENER,PARM='SIZE=2000K'

ICEGENER will treat SIZE=2000K as an invalid DFSORT OPTION parameter and will transfer control to IEBGENER, which will terminate because it treats SIZE=2000K as an invalid parameter.

Thus, you can pass PARM parameters to ICEGENER that are valid as DFSORT OPTION parameters, but you must be aware that if ICEGENER transfers control to IEBGENER, those parameters will cause IEBGENER to terminate. PARM parameters that are not valid as DFSORT OPTION parameters (even if they are valid as DFSORT PARM parameters) will cause ICEGENER to transfer control to IEBGENER, which will terminate.

ICEGENER can transfer control to IEBGENER due to DFSPARM or SORTCNTL statement errors or other errors detected by DFSORT. Therefore, we recommend that ICEGENER not be used for any application for which IEBGENER cannot be used, to avoid unwanted IEBGENER processing. For example, if ICEGENER is used with an INCLUDE statement in DFSPARM, IEBGENER could be used and complete successfully, but the INCLUDE statement would be ignored. Instead, DFSORT copy should be used directly so that IEBGENER cannot be called.

However, if you know that ICEGENER will use DFSORT copy, you can use a DFSPARM data set with ICEGENER to pass control statements and parameters to DFSORT. For example, if you specify:

//DFSPARM DD *
  OPTION SPANINC=RC0
/*

and ICEGENER uses DFSORT copy, any incomplete spanned records DFSORT detects in a variable spanned input data set are eliminated.

If your site has installed ICEGENER to be invoked by the name IEBGENER, you need not make any changes to your applications to use ICEGENER. If your site has not chosen automatic use of ICEGENER, you can use ICEGENER by substituting the name ICEGENER for IEBGENER on the EXEC statement (when DFSORT is directly invoked) or LINK macro (when DFSORT is program-invoked) in any applications you choose. Program-invoked applications must be recompiled.

Following is an example of how an IEBGENER application can be changed to use ICEGENER by substituting the name ICEGENER for the name IEBGENER in the EXEC statement.

//GENER JOB...
// EXEC PGM=ICEGENER
//SYSPRINT DD SYSOUT=*
//SYSUT1 DD DSN=CONTROL.MASTER,DISP=OLD,UNIT=3380,VOL=SER=MASTER
//SYSUT2 DD DSN=CONTROL.BACKUP,DISP=OLD,UNIT=3380,VOL=SER=BACKUP
//SYSIN DD DUMMY

The IEBGENER DD statements SYSUT1 (input), SYSUT2 (output), and SYSPRINT (messages) are used by DFSORT for SORTIN, SORTOUT, and SYSOUT, respectively. These DD statement names will be translated by using an extended parameter list to invoke the copy function. If DFSORT cannot be used (for example, because IEBGENER control statements are specified), control will be transferred to IEBGENER.

Note:

The SYSUT2 data set should not be the same as the SYSUT1 data set because this can cause lost or incorrect data or unpredictable results.
Whether ICEGENER is invoked from a program or not, DFSORT will be invoked from ICEGENER using an extended parameter list. Therefore, the installation defaults for the ICEAM2 or ICEAM4 environment, or for an ICETDx environment if activated for ICEAM2 or ICEAM4, apply and SORTCNTL or DFSPARM can be used to provide additional control statements for the copy application; for example, OPTION. However, ICEGENER can transfer control to IEBGENER due to DFSPARM or SORTCNTL statement errors or other errors detected by DFSORT. Therefore, DFSORT copy should be used directly rather than ICEGENER if DFSORT processing statements such as INCLUDE, OUTREC, SUM and so on are required.
For most error conditions that prevent the use of DFSORT copy, control will be transferred to the IEBGENER system utility. DFSORT messages will not be printed unless a SORTDIAG DD statement is supplied. Use of the SORTDIAG DD statement will allow you to determine why DFSORT copy could not be used.
If DFSORT copy is used, its operation and messages will be equivalent to a directly called DFSORT copy application. If an unrecoverable error is encountered (for example, an I/O error), DFSORT's return code of 16 will be changed by ICEGENER to a return code of 12 to emulate the return code from a failing IEBGENER application.
DFSORT copy can perform some functions not provided by IEBGENER, such as certain padding and truncation operations. ICEGENER processing is not identical to IEBGENER processing in all cases, since DFSORT copy uses methods to enhance performance (EXCP, for example) that are not used by IEBGENER.
In some cases, IEBGENER terminates when the SYSUT2 LRECL is different from the SYSUT1 LRECL. ICEGENER takes one of three actions depending on the GNPAD (LRECL padding) or GNTRUNC (LRECL truncation) installation option, as appropriate.
If you want ICEGENER to transfer control to IEBGENER when the SYSUT2 LRECL is larger than the SYSUT1 LRECL, use installation option GNPAD=IEB. If you want ICEGENER to handle LRECL padding, use GNPAD=RC0 (the supplied default) or GNPAD=RC4.

If you want ICEGENER to transfer control to IEBGENER when the SYSUT2 LRECL is smaller than the SYSUT1 LRECL, use installation option GNTRUNC=IEB. If you want ICEGENER to handle LRECL truncation, use GNTRUNC=RC0 (the supplied default) or GNTRUNC=RC4.
For a call to ICEGENER, or to IEBGENER as an alias for ICEGENER, register 1 must point to a valid parameter list consisting of three addresses as follows:
- Address1: The address of the Option List.
- Address2: The address of the Alternate DDname List.
- Address3: The address of the Page Number List.
Methods of calling ICEGENER that generate a valid parameter list will allow ICEGENER to use DFSORT's copy feature, whereas methods of calling ICEGENER that generate an invalid parameter list will cause ICEGENER to transfer control to IEBGENER. For example:
```
call *(icegener)
```
on the TSO command line generates a valid parameter list, whereas:
```
icegener
```
on the TSO command line generates an invalid parameter list.