Example 12: Reblock Load Library and Distribute It to Different Device Types

In this example, a load library is distributed (by copying it) to devices whose maximum block size differs from that on which the original load library resides. The library is first reblocked to a maximum block size that is compatible with each of the devices to which the library will be copied. Then, the library is copied to those devices.

This example illustrates how load libraries can be developed on one type of direct access device and then distributed to other types of direct access devices.

  //RBLKCOPY JOB  ...
  //REBLOCK  EXEC PGM=IEBCOPY
  //SYSPRINT DD   SYSOUT=A
  //TESTED   DD   DSN=TESTED.MASTER.LOADLIB,DISP=SHR
  //STDSIZE  DD   DSN=PROGRAM.MASTER.LOADLIB,DISP=(OLD,KEEP),
  //              UNIT=3390,VOL=SER=PROG01,DCB=(BLKSIZE=23470)
  //SYSIN    DD   *
             COPYMOD OUTDD=STDSIZE,INDD=TESTED,MAXBLK=13030
  /*
  //DISTRIB  EXEC PGM=IEBCOPY
  //SYSPRINT DD   SYSOUT=A
  //STDSIZE  DD   DSN=PROGRAM.MASTER.LOADLIB,DISP=SHR
  //LIB3350  DD   DSN=PROGRAM.LIB3380.LOADLIB,DISP=(OLD,KEEP),
  //              UNIT=3380,VOL=SER=PACK01,DCB=(BLKSIZE=19069)
  //LIB3330  DD   DSN=PROGRAM.LIB3380.LOADLIB,DISP=(OLD,KEEP),
  //              UNIT=3380,VOL=SER=PACK02,DCB=(BLKSIZE=13030)
  //SYSIN    DD   *
             COPY OUTDD=LIB3380,INDD=STDSIZE
             COPY OUTDD=LIB3380,INDD=STDSIZE
  /*

The control statements are discussed below:

The REBLOCK EXEC statement begins the reblocking step.
TESTED DD defines the cataloged load library TESTED.MASTER.LOADLIB.
STDSIZE DD defines an existing data set, PROGRAM.MASTER.LOADLIB, which resides on a 3390 direct access device and has a block size of 23470.
The COPYMOD statement in the SYSIN data set specifies that TESTED.MASTER.LOADLIB is to be merged into PROGRAM.MASTER.LOADLIB. It also specifies that PROGRAM.MASTER.LOADLIB is to be reblocked with a maximum block size of 13030. This block size is chosen because it is small enough to fit on both 3380 and 3390 direct access devices.
The DISTRIB EXEC statement begins the distribution step, where the reblocked data set is copied to devices with different maximum block sizes.
STDSIZE DD defines the same data set that was reblocked in the previous step.
LIB3380 DD defines the data set PROGRAM.LIB3380.LOADLIB, which resides on a 3380 direct access device.
The COPY statements in the SYSIN data set specify that the data set PROGRAM.MASTER.LOADLIB is to be copied to the output data sets without being reblocked. If PROGRAM.MASTER.LOADLIB had not been reblocked to the smaller block size, this step would end unsuccessfully.