CA Dynam for VSE User Guide

Using Automatic Multifile (AMF) Data Sets
This statement creates the next AMF data set name in sequence. For instance,
if the last DSN on the current set was AMF008, CA Dynam/T would create DSN
AMF009 and place it in the Catalog as file one of a new AMF set. The next time
the job creating the AMF DSN is run, AMF009 is used. You can then delete
DSNs AMF002 through AMF008. This frees space in the Catalog. The base
DSN, AMF***, must remain in the Catalog; it contains pointers to the data set
names currently in use.
Scratching More Than the Last AMF DSN
If you manually scratch a tape other than the last DSN of an AMF set, you
must tell CA Dynam/T which DSN to use next for output.
For instance, suppose data sets AMF001 through AMF008 had been created,
but data sets AMF005 through AMF008 contained bad data and had to be
recreated, then do the following:
1. Scratch DSN AMF005 using DYNCAT DELETE. This would scratch AMF005
through AMF008 because CA Dynam/T always scratches forward on
chained multifile data sets:
DELETE 'AMF005' ALL
2. Issue the following DYNCAT update statement:
ALTER 'AMF***' MF=005
This update statement tells CA Dynam/T to use DSN AMF005 for outputting
the next file of this AMF set. The same procedure must be followed when
members of the current AMF set are deleted.
Inputting AMF Data Sets
Several methods are available to call for the desired input AMF data set. The
following examples assume that AMF001 through AMF014 have all been
created on the same tape. AMF014 is the latest (last) file. Each of the
following will result in DSN AMF007 being the data set requested (provided the
file is being opened for input):
// TLBL INFILE,'AMF***',,,,,8 (version number field)
// TLBL INFILE,'AMF***',,,,7 (file sequence number field)
// TLBL INFILE,'AMF***.(-7)' (relative generation)
// TLBL INFILE,'AMF007' (real DSN)
// TLBL INFILE,'AMF***',,,,7,2 (file sequence overriding version)
Subsequent files of AMF sets are also subsequent generations; thus, cyclic
control of these data sets does not apply. You can set retention dates and use
the MF=NEW option to divide the AMF data sets into easily manageable groups
of tapes.
Chapter 2: Maintaining Tape Files 2–71