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 as well.

IMUF can be MUF-plexed or shared with other CA solution address spaces without any impact on ENF operation, though there is likely to be little, if any, benefit on behalf of ENF 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 normally would have been included in the JCL for the external MUF started task procedure, must be included in the ENF started task procedure for IMUF operation.

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

There are only two discernable differences between standard MUF operation and IMUF operation:

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

  For instructions on how to use the IMUFCMD, see The ENF 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 ENF started task procedure. This directs ENF to load the appropriate support routines and initialize the IMUF environment. Datacom/MUF startup/status messages will be posted to the ENF job log along with ENF startup/status messages.

Partial example illustrating placement of the IMUF statement:

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