CAIENF Control Options › Imbedded Multi-User Facility (IMUF) Option › IMUF Implementation and Startup

IMUF Implementation and Startup

An IMUF is configured and customized exactly as it would have been configured and customized for standard (external) MUF operation as described in the CA Datacom/AD Installation and Maintenance Guide.

IMUF is not "MUFLite". The same rules and regulations that apply to external MUF operation, apply to IMUF operation too.

IMUF can be MUF-plexed or can be shared with other CA Technologies solution address spaces without any impact on CAIENF operation. Though there is likely to be little, benefit on behalf of CAIENF by doing so.

In a mutli-MUF environment, IMUF must be uniquely identified through the CA-Datacom/AD DBSIDPR element like any other MUF.

All of the job steps and DD statements that typically would have been included in the JCL for the external MUF started task procedure, must be included in the CAIENF started task procedure for IMUF operation.

A small amount of "handshaking" logic has been added to CAIENF and CA-Datacom/AD to support IMUF operation, but essentially, the IMUF is unaware that it is running as a CAIENF subtask.

The two discernable differences between standard MUF operation and IMUF operation:

• In IMUF mode, CAIENF attaches the MUF, within its own borders, rather than by a z/OS initiator.
• Because CAIENF is in control of the address space, the CAIENF command processor seized control of the address space operator communication "handle" by the time IMUF is launched. The IMUF is unable to listen directly for, and respond to, operator modify (F) or stop (P) commands that are intended for the IMUF task. However, CAIENF and the IMUF task negotiate a "handshake" during startup that, in addition to synchronizing CAIENF/IMUF startup and shutdown procedures, lets CAIENF forward MUF-specific operator commands to IMUF through the CAIENF command processor.

  For instructions on how to use the IMUFCMD, see The CAIENF Imbedded Multi-User Facility Command.

To activate the IMUF feature, place a single "IMUF" statement anywhere in the ENFPARMS PDS member or data set of the CAIENF started task procedure. This directs CAIENF to load the appropriate support routines and initialize the IMUF environment. Datacom/MUF startup/status messages are posted to the CAIENF job log with CAIENF startup/status messages.

Partial example illustrating placement of the IMUF statement:

//ENFPARMS   DD  *
……
DCM(CAS9DCM0)
DCM(CAS9DCM2)
……
IMUF
RECORD(YES)
……
/*