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IXRCDS: Retain VIERS in Virtual Storage

z/OS DFSMSdfp Advanced Services
SC23-6861-01

This keyword applies to indexed VTOCs only.
IXRCDS=KEEP
Specifies that VIERs read into storage are to be kept in virtual storage. The VIERs are retained even if processing cannot complete successfully. The CVAF parameter list in field CVIRCDS contains the address of a buffer list with the VIR buffer addresses and RBAs of the VIERs read.

The index search function dynamically updates the buffer list and, when necessary, obtains additional buffer lists and chains them together.

If IXRCDS=KEEP is specified and no buffer list is supplied to CVAF in the CVPL, CVAF obtains a buffer list and buffers and reads the first high-level VIER. The address of the buffer list is placed in the CVMICDS field of the CVPL.

The buffer list and VIR buffers are in your protect key. The subpool is 0 if you are not authorized; it is subpool 229 if you are.

If IXRCDS=KEEP is coded for a nonindexed VTOC, a request to read or write a DSCB is performed, but an error code is returned.

When processing on the current volume is finished, release all areas that were kept.

IXRCDS=(KEEP,addr)
The index records buffer list address from one CVAF request is being passed to this CVAF parameter list by specifying its address as the second parameter in the IXRCDS keyword.
IXRCDS=NOKEEP
If IXRCDS=NOKEEP is coded, the VIERs that are accessed (if any) are not retained. Furthermore, the buffer list supplied in the CVIRCDS field in the CVAF parameter list is released, as are all buffers found in the buffer list. If the skip bit is set in any entry in the buffer list, the buffer and buffer list are not freed. This is the default.
IXRCDS=(NOKEEP,addr)
Specifies that previously accessed VIERs are not to be retained.
You must free buffer lists and buffers obtained by CVAF. This can be done in one of three ways:
  • By coding IXRCDS=NOKEEP on the CVAFDIR macro that obtained the buffers
  • By coding IXRCDS=NOKEEP on a subsequent CVAF macro
  • By coding CVAFDIR ACCESS=RLSE and providing the address of the buffer list in the BUFLIST keyword.
Requirement: You must enqueue the VTOC and reserve the unit to maintain the integrity of the VIERs read.

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