CA Dynam for VSE User Guide

Using Automatic Multifile (AMF) Data Sets
Any combination of letters and numbers can be used as with any other DSN.
The only restriction is that there must be three asterisks (***) somewhere in
the DSN; they indicate where the three-digit numbers will be inserted.
The following are valid data set names for AMF data sets:
'AMF***'
'PAYROLL BACKUP***'
'FILE***PR TRANS'
Example:
This DEFINE statement creates a multifile data set named 'AMF***'. It is the
prototype for the AMF set.
DEFINE 'AMF***' NGEN=1 MF=AUTO
A program creating the file above using file name OUTFILE would require a
TLBL as below:
// TLBL OUTFILE,'AMF***'
The first time this job is run, CA Dynam/T creates version one of data set
AMF001. The next time, CA Dynam/T finds a valid version for AMF001; it
subsequently creates a new data set, AMF002.
If the data set AMF002 was not closed or if it was closed and later scratched
manually, this same DSN would be used the next time the job was run. In
other words, the last file on the existing AMF set is checked to see if it contains
a good version. Depending on whether it contains a valid version CA Dynam/T
does the following:
• If it does contain a valid version, CA Dynam/T adds one to the DSN and
creates a new DSN as the last file on the AMF set. Each data set created
will have the same characteristics (retention, owner, and so on.) as the
base data set.
• If it does not contain a valid version, CA Dynam/T uses the DSN again.
Volume Switching with AMF Data Sets
CA Dynam/T provides automatic volume switching when end-of-volume is
reached.
Use the DYNCAT ALTER command whenever you want to start the next file on
a separate volume:
ALTER 'AMF***' MF=NEW
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