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Customizing File Manager
Customizing File Manager to use an I/O exit
Using the I/O exit control block
The I/O exit control block is a single parameter that is passed with each call from File Manager to the I/O exit and returns data from the I/O exit to File Manager.
Information that should always be returned from the I/O Exit to File Manager

Customizing File Manager
- Preparing to customize File Manager
- Customizing the operating environment for File Manager
- Customizing File Manager
- Customizing the File Manager security environment
  File Manager provides security for system-oriented functions through ®either RACF (or an equivalent security product) or the FMNSECUR exit.
- Customizing File Manager to write audit records to SMF
- Customizing the File Manager audit facility for the File Manager Base component
- Customizing File Manager for national languages
  You can customize File Manager for national languages other than English.
- Customizing File Manager Service Provider for z/OS® Connect
  File Manager Service Provider for IBM® z/OS® Connect Enterprise Edition enables client applications to access IBM Z data sources using z/OS Connect.
- Customizing File Manager to use library management system libraries
- Customizing File Manager to use the Optim™ Data Privacy Provider API
- Customizing File Manager to use an I/O exit
  - Exit protocol
  - Writing your exit
  - Exit control block data names
  - Using the I/O exit control block
    The I/O exit control block is a single parameter that is passed with each call from File Manager to the I/O exit and returns data from the I/O exit to File Manager.
  - Installing your exit
- Customizing File Manager to use a scrambling exit
- Verifying the customization of File Manager
  After you have completed the initial installation and customization of File Manager Base function, you can perform the following steps to verify your customization.

Information that should always be returned from the I/O Exit to File Manager

The I/O exit should set any non-zero exit return code as appropriate. The exit return code field is initialized to zero on every call from File Manager to the exit.

The I/O exit can also set an informational, warning, or error message into the message field of the I/O exit control block. You can code your exit to return any number of messages, however File Manager will suppress all informational (RC=0) and warning (RC=4) messages after the first 100. Error messages (RC=8 or higher) are never suppressed. The File Manager message:

Number of messages issued by exit reached the limit. Remaining non-error (RC < 8)
messages will be suppressed

is issued after 100 non-error messages have been produced. The limit of 100 messages cannot be changed.

The I/O exit can set the warning code to 2 at any time, to tell File Manager to continue processing and not call the I/O exit again. The I/O exit will still be called for termination and, if an open was made, for close. For File Manager to check the warning code, the I/O exit must also set the exit return code to 4 (warning).