DFSMSdss tape read channel programs are built to read the maximum possible amount of data that any version of DFSMSdss can create. DFSMSdss provides a patch byte to modify how DFSMSdss builds channel programs to read tape blocks. You can control this function by setting the flag at offset X'59' in ADRPATCH. The valid settings are:

X'00'

DFSMSdss continues to build channel programs to read the maximum amount of data that can be created by DFSMSdss.

Any other value

DFSMSdss builds channel programs to read the maximum block size written to the dump data set that the restore is being performed on.

To set the flag on dynamically, use the SET PATCH command to set the patch byte at offset X'59' to a value of X'FF'. To set the flag on permanently, modify the sample JCL (see Sample JCL) as follows:

//SYSIN DD *
NAME ADRDSSU ADRPATCH
VER   59        00
REP   59        FF