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Trident Services Provides New Free Exit Analysis Tool

Trident Services, Inc. released FEMSNIFR, a utility that searches the IBM z/OS system for more than 500 exit points and gathers the information into a detailed report. For in-depth information, go to learn more.

Customization via Exit Programs

From the earliest days of the operating system, provision has been made to customize system operation by augmenting the operating system with code provided by the installation. The operating system and associated products provided exit points from which installation exit routines are called. The installation exit code typically must be written in assembler language and execute in an authorized state. This is to say that an installation must express the JCL rules and other policies in assembler code in a way that can crash the system.

The Current Concerns

Even now, 50 years later, a good deal of customization must still be done using installation exits. However, the level of skill in assembler language has diminished greatly. Perhaps worse, the knowledge of operating system internals required for implementing and maintaining installation exits has nearly vanished. Many installations know little about the exit code that runs on their critical production systems. In some cases, they don’t even know the inventory of the active installation exit code.

Addressing the Exits Issues

The first step is to locate and inventory the exit code. Trident Services has created a powerful utility to find and identify the installation exit routines associated with the exit points provided by z/OS elements and related products. Having identified the exit routines and located the source code, it’s possible to “reverse engineer” the installation policy they are attempting to enforce. Once the installation policy is determined, much of the exit code can be replaced with zOSEM functionality and the installation’s exit code can be retired.


Exit Points are listed by Group, e.g. JES2 or TSO. The exit point name and the name and location of the exit load module are listed. The first 80 byte of the exit load module are listed. They may provide a clue as to the source of the module.

Specifying Rules to zOSEM

The installation specifies the JCL and Job rules on ISPF panels. The policy can be updated and later activated. The updated policy can be activated dynamically without re-IPLing or recycling JES2 or other subsystems. zOSEM also supports the addition of custom exit routines which can be updated dynamically in the rare case that there is something zOSEM doesn’t handle.

Simplify Your Next z/OS Upgrade

Eliminate (or greatly reduce) your custom assembler language exits. Translate your existing exit functionality to zOSEM functions and specify policy via ISPF panels instead of writing assembler code. Trident will help with the specification. zOSEM supports new z/OS releases at GA and all customizations are preserved with no effort.

About Trident Services

Trident Services, Inc. is a privately held California corporation with current small business certification, and holds both GSA and CMAS contracts. We are a committed member of the Mainframe community and have been an IBM Business Partner for over 25 years. Trident Services began as a consulting firm, and it was through this experience that we identified needs within the industry. Since launching our first software solution in 1988, we have continued to develop and enhance our software products and services to keep pace with industry changes, emerging technologies and client driven needs. Our flagship product, zOSEM (zOperating System Environment Manager) is a powerful software tool of strategic importance in the enterprise server environment. Driven by a simple ISPF interface, zOSEM encompasses a multitude of features for improved control, throughput, and processing efficiency in a z/OS environment. zOSEM is enabling customers to reduce & control ISV costs, eliminate exit migration issues, and provides an easy-to-use DFSMShsm Optimizer which can dramatically improve HSM performance. Working smarter is a necessity in today's economic climate; Trident customers can relax knowing they have a smart solution that Saves Time, Money and Maximizes Resources!

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