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zCICS VSAM Guide

zCICS VSAM Installation

I recommend that the catalog and file structures are kept in a common directory. More flexibility will be added if time permits.

Step 1

  • Create and assemble a catalog and the files it is to contain using the DEFINE macro.
  • The test files used in zZ390\cics are in the cics\vsam subdirectory, and many more examples in vsam\demo.
  • Multiple catalogs are supported.

Step 2

  • Use REPRO to create the VSAM base cluster, paths and alternate indexes as needed.

Step 3

  • Add the FCT entries for your files to DFHFCTUS and assemble.

Step 4:

  • Add SET statements to Z390FILE.BAT to define the catalog and filename that will be used at OPEN time.

VSAM Extensions

The following facilities are not supported in standard CICS/VSAM, but they are in zCICS VSAM: - Support of 4 gigabyte files and record sizes greater than 32K for all VSAM file types. - Skip-sequential access (browse) of an ESDS by RBA (fixed or variable), forward or backward.

[!NOTE] Knowledge of the file will be necessary for variable ESDS in order to set the initial RBA.

VSAM limits

  • For KSDSs and AIXs, there is an internal limit on all keylengths of 128 bytes. Please raise an issue if this is not sufficient for you.
  • There is an internal limit in zCICS on record sizes of 32K bytes. Please raise an issue if this is not sufficient for you.