Defining resources with DFHCSDUP

The CSD update batch utility program DFHCSDUP is an offline utility program that you can use to define CICS® resources. See How you can define CICS resources for an introduction to DFHCSDUP and a comparison with alternative methods of resource definition. You can use DFHCSDUP to read from and write to a CICS system definition file (CSD), either while CICS is running or while it is inactive.

Restriction: DFHCSDUP opens the CSD in non-RLS mode, even when you request RLS access on your JCL. This means that, if you access the CSD from CICS in RLS mode, it cannot be open when you run DFHCSDUP. The reason for the restriction is that DFHCSDUP does not have the capabilities that are needed to open a recoverable file in RLS mode. The restriction also applies, however, if your CSD is nonrecoverable.

What you can do by using DFHCSDUP commands

Resource management utility DFHCSDUP commands lists the available commands. You can use DFHCSDUP to perform the following tasks:
  • Add a group to the end of a named list in a CSD file (ADD command)
  • Alter attributes of an existing resource definition. on the CSD (ALTER command)
  • Append a group list from one CSD file to a group list in another, or in the same, CSD file (APPEND command)
  • Copy all of the resource definitions in one group to another group in the same, or in a different, CSD file (COPY command)
  • Copy a single resource definition from one group to another group (COPY command)
  • Define a single resource, or a group of resources, on the CSD (DEFINE command)
  • Delete from the CSD a single resource definition, all of the resource definitions in a group, or all of the group names in a list (DELETE command)
  • Extract data from the CSD and pass it to a user program for processing (EXTRACT command)
  • Initialize a new CSD file, and add to it the CICS-supplied resource definitions (INITIALIZE command)
  • List selected resource definitions, groups, and lists (LIST command)
  • Process an APAR—that is, apply maintenance for a specific APAR to the CSD (PROCESS command)
  • Remove a single group from a list on the CSD file (REMOVE command)
  • Scan all IBM®-supplied and user-defined groups for a resource (SCAN command)
  • Service a CSD file when necessary (SERVICE command)
  • Upgrade the CICS-supplied resource definitions in a primary CSD file for a new release of CICS (UPGRADE command)
  • Define resources using a set of user-defined default values (USERDEFINE command)
  • Verify a CSD file by removing internal locks on groups and lists (VERIFY command)

How to invoke DFHCSDUP

You can invoke DFHCSDUP in two ways:

You can also write your own programs that modify or extend DFHCSDUP. See User programs for the system definition utility program (DFHCSDUP).

Error handling

The reaction of DFHCSDUP to an error (with return code 8 or greater) depends on the nature of the error and on how DFHCSDUP is invoked.
As a batch program
If the error occurs during connection of the CSD, no subsequent commands are completed. If the error occurs elsewhere, no subsequent commands are executed other than LIST commands. The put-message-exit routine is not applicable if DFHCSDUP runs as a batch program.
From a user program
DFHCSDUP exits can be used to control error processing. See User programs for the system definition utility program (DFHCSDUP). If you provide a put-message-exit routine for DFHCSDUP, it is invoked whenever a message is issued. If an error is detected while DFHCSDUP is receiving commands from a get-command exit, all subsequent commands are processed if possible.

Security for DFHCSDUP

DFHCSDUP requires batch access to the CSD. Ensure that only authorized users are allowed to update the CSDs. Restrict the access list on the CSD data set profile to the CICS region user IDs and other authorized users only. For more information, see Protecting data sets in z/OS Security Server RACF Security Administrator's Guide.