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Table of Contents
- Checking Error Information
- Protecting Data When File Access is Shared
- Writing Directly to Disk
- Recovering from a System or Software Abort
- Backing Up KSAM Files
- Recovering from Index Corruption
Attention must be paid to protecting a KSAM file's data. Check an intrinsic's
status after a call to find information about a failed routine. The
FCHECK and FERRMSG intrinsics provide error codes and
messages after an intrinsic call has failed.
Various intrinsics control file access when a file is shared
by more than one process. Locking and unlocking the file controls
access to a shared file during critical modification operations.
The item numbers 2 and 6 of the FCONTROL intrinsic ensure that data
is written to the disk before processing is allowed to continue. This protects
the data from system and software aborts that may occur between the time that
data is written to the transaction log and the time that it is actually written
to the disk. Transaction management provides automatic recovery from system and
software aborts.
Regular maintenance and file backups are needed for data protection
against hardware failures or improper processing. If index corruption
exists, files can be restored quickly through the FCOPY facility.
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