DSM/Tape Catalog User's Guide

Tape File Concepts
DSM/Tape Catalog User’s Guide 520233-008
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Expiration Date for an Incomplete Tape File
the job, the application would request the incomplete file as the current generation
to read.
Another advantage is that this procedure does not leave gaps in the absolute
generation numbers.
This procedure is also effective when your application uses the same tape file
names for input and output tape files. Immediately deleting the incomplete tape file
entry prevents another application from requesting it.
Instruct the operator to revise the output DEFINE so a new version of the same
generation is created after the application is rerun.
This procedure is an alternative to the previous case; it is another way to rerun an
application without disturbing the absolute generation numbers of the tape file
entries. After the application runs again, a new version is created within the
generation of the original run. The latest version becomes the valid tape file entry.
For example, an application uses this DEFINE for its output file:
7> ADD DEFINE =OUT, CLASS TAPECATALOG,&
7> & LABELS ANSI,&
7> & FILEID MASTER_OUT,&
7> & VOLUME SCRATCH,&
7> & POOL MKT_TAPES,&
7> & USE OUT,&
7> & GEN +1
At its next run, the application fails before writing all the records to MASTER_OUT.
The catalog has an entry for generation 3 of MASTER_OUT, which represents an
incomplete tape file. Before rerunning the application, the operator changes the
DEFINE to:
15> ADD DEFINE =OUT, CLASS TAPECATALOG,&
15> & LABELS ANSI,&
15> & FILEID MASTER_OUT,&
15> & VOLUME SCRATCH,&
15> & POOL MKT_TAPES,&
15> & USE OUT,&
15> & GEN 3,&
15> & VERSION NEW
The application runs to a successful completion, and the file cat
alog has these
entries for MASTER_OUT:
File Name Absolute Generation Version Version Status
MASTER_OUT 1 0 Valid
MASTER_OUT 2 0 Valid
MASTER_OUT 3 0 Invalid
MASTER_OUT 3 1 Valid