Message Control Facility

issues messages at many different points to inform you of its actions. Some messages may seem unnecessary or only appropriate for specific individuals responsible for storage management. The Message Control Facility (MCF) lets you discard these messages or direct them to a specific user or MVS console routing code.
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Allocate
issues messages at many different points to inform you of its actions. Some messages may seem unnecessary or only appropriate for specific individuals responsible for storage management. The Message Control Facility (MCF) lets you discard these messages or direct them to a specific user or MVS console routing code.
You direct the MCF by creating a message preprocessing table using assembler macro specifications that you assemble and link with
Allocate
. You can redirect most messages using the MCF. Some exceptions follow:
  • Messages issued during the installation and removal of the Operating System Interfaces, either before the MCF itself has been initialized or after it has been shut down.
  • Any message issued directly through the IBM WTO macro. This exception applies to only a small percentage of messages.
The following diagram illustrates MCF:
Allocate_Message Control Facility
After implementation, the message control facility is active for all allocations. MCF can be temporarily deactivated in any job step by adding the VDSDIAGS DD statement or by allocating it to your TSO session. The VDSDIAGS DD statement in TSO or batch JCL causes all messages to be displayed in a normal manner. To use a different ddname for this purpose, specify the DEBUGDD= keyword on the SCANBEG macro.