If the system fails when a KSAM file is open for any type of access except read-only, the file cannot
be reopened until it has been recovered. In such a circumstance, any attempt to reopen the file
causes the following message to be issued:
#192 -- SYSTEM FAILURE OCCURRED WHILE THE KSAM FILE WAS OPENED
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The file is easily recovered in most cases by running KSAMUTIL.PUB.SYS and then requesting
KEYINFO. This command resets any incorrect end-of-file marks and deletes any key values that
point to non-existent data records. If key values are missing or are out of sequence, the keys cannot
be recovered by KEYINFO and, in this case, the file must be reloaded. (You can refer to section II
for a discussion of KEYINFO; also an example of file recovery and reloading is provided later in
this appendix,) If you want to examine the file statistics, you can run the VERIFY command of
KSAMUTIL using the NOCHECK option. (If KEYINFO does not complete execution successfully,
then the KSAM file must be reloaded.)
For most purposes, this is all you need to know in order to recover a file when a system failure
prevents you from opening it. This appendix provides internal details that explain why recovery is
necessary and what KEYINFO does in order to recover. It is intended primarily for the
sophisticated programming staff.
