Derivation: MeSsaGe Queue

MSGQ specifies the number of ISI blocks that Language Environment allocates on a per thread basis for use by the application. The ISI contains information for Language Environment to use when identifying and reacting to conditions, providing access to q_data tokens, and assigning space for message inserts used with user-created messages. When an ISI is needed and one is not available, Language Environment uses the least recently used ISI. CEECMI allocates storage for the ISI, if necessary.

Non-CICS default

MSGQ=((15),OVR)

CICS® default

MSGQ is ignored under CICS.

Syntax

                                .-OVR----.      
>>-MSGQ--=--(--(--number--)--,--+-NONOVR-+--)------------------><

number

An integer that specifies the number of ISIs to be maintained per thread within an enclave.

OVR

Specifies that the option can be overridden.

NONOVR

Specifies that the option cannot be overridden.

Usage notes

PL/I MTF considerations

In a PL/I MTF application, MSGQ sets the number of message queues allowed for each task.

For more information

• For more information about the CEECMI callable service, see z/OS Language Environment Programming Reference.
• For more information about the ISI, see z/OS Language Environment Programming Guide.