VTOC Error Responses

The following actions are taken if an error occurs in the VTOC:

If an index structure error is detected and if the address space is enqueued on the VTOC, then DADSM or CVAF disables the VTOC index. The indexed VTOC bit is zeroed in the format-4 DSCB, a software error record is written to SYS1.LOGREC, and a system dump is taken at the next call to DADSM create or extend. The VTOC is converted to a nonindexed format at the next DADSM create or extend call.
If a program check, machine check, or other error occurs while using a VTOC access macro, a SYS1.LOGREC record is written, and a system dump is taken.
An error code is put in the CVSTAT field of the CVPL. The values and explanations of these error codes are listed in VTOC Index Error Message and Associated Codes.