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Diagnosing
CICS Problems
Using No-
Charge
Supplied
Facilities
By Phyllis Donofrio
In this age of budget-challenged IT
resources, many sites are finding it
necessary to use facilities readily
available and shipped with the product
rather than turning to outside sources
that usually come with a monthly or
yearly license fee. While those products
are certainly admirable and usually provide
function not available with the
supplied facilities, they may be beyond
the reach of some shops’ budgets.
With that in mind, it may be worth
reviewing facilities that you may not
have known were available or may have
forgotten were updated and shipped
with every new release. The CICS developers
in Hursley, U.K., spend a great
deal of resources and effort to keep
these facilities current, and provide support
for new product enhancements
that come with every release. There may
be a time when Hursley resources, just
as our own, are stretched and decisions
must be made whether to continue support
for some of these facilities.
The CICS Operations Guide
The CICS Operations Guide is one of
two publications that document the
facilities and the proper syntax for using
them. Updated with every release, the
CICS Operations Guide uses a vertical
bar (|) to show whether a facility has
been added or changed with that particular
release. While these facilities
aren’t “CICS Supplied Transactions,”
they’re modules or utilities shipped to
assist customers with diagnosing CICS
problems and support issues. Make sure
you use the publication that matches
the version of CICS you’re running.
While this publication contains a great
deal of information, this article will
cover three components:
• DFHEISUP: the load module scanner
• DFHDUnnn: the transaction dump
formatter
• DFHPDnnn: the system dump formatter.
The “nnn” in the module name refers
to the particular version/release of CICS
you’re using. Every version must be formatted
with its own module; for example,
DFHDU640 would format dumps
from CICS TS 3.2. These modules ship
with every release and refer to control
blocks specific to that release.
Load Module Scanner
The load module scanner,
DFHEISUP, is a utility that helps you
identify which load modules in your
CICS load libraries contain specific
Application Program Interface (API) or
Serial Peripheral Interface (SPI) commands
you’ve listed or identified. For
example, if you know a command
should be changed to take advantage of
a new feature in CICS, you can use the
load module scanner to identify all the
program modules that contain that
command. For example, you could look
for threadsafe or non-threadsafe commands.
The list of API commands that
aren’t threadsafe is well-documented
and can be used with this utility to
determine if applications currently running
are viable candidates. Many customers
can’t find (or don’t have) the
source to some of the old legacy programs,
so this utility could be used
without source code, scanning only the
module from the existing load library.
Transaction Dump Formatter
The transaction dump utility program,
DFHDUnnn, formats transaction
dumps written to DFHDMPA or
DFHDMPB, whichever is specified in
the batch job. These dump data sets are
retained across a restart of CICS, but
once opened a second time, the contents
are rewritten and the previous
contents are removed. If you wish to
retain any history of these dumps, a
process should be created to regularly
copy them to files so they can be referenced.
There are several program products
that format these dumps and retain
the output, but again, if your installation
is budget-constrained, this utility is
available and shipped free with the
product.
A sample job stream for this utility is
well-documented in the CICS Operations
Guide. Simple and straightforward, it
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