QUEUE - reserve table entries for temporary messages queues

The QUEUE control statement allows you to specify the number of temporary queues that are permitted to exist in the application at any one time. In the KDCFILE the appropriate number of table entries are reserved for temporary queues. You can also define the default settings for these queues.

Temporary queues are suitable, for example, for communication between two services. These can be created and deleted dynamically during operation using the KDCS calls QCRE and QREL.

The QUEUE statement may only be specified once during a generation run!

For more information about queues and possible applications please refer the openUTM manual “Concepts und Functions”.

QUEUE

NUMBER=queue-number   [ ,QLEV=queue_level_number ]  [ ,QMODE = { STD | WRAP-AROUND } ]

NUMBER=	queue-number Specifies the maximum number of temporary queues that are permitted to exist at any one time during an application run. Minimum value: 1 Maximum value: 500.000
QLEV=	queue_level_number (Queue Level) Specifies the standard value for the maximum number of messages that may exist at any one time in a temporary message queue. The maximum number of messages can be defined specifically using the KDCS call QCRE (KCLA parameter) for each queue when the queue is generated. The default value generated with QLEV= is used if the value 0 is entered in the parameter KCLA. QLEV=32767 means that the number of messages in the queue is not limited by default. Default: 32767 (or in other words, an unrestricted queue length) Minimum value: 1 Maximum value: 32767 (or in other words, an unrestricted queue length)
QMODE=	(Queue Mode) Determines the behavior of openUTM in the event that the maximum number of messages saved in a temporary queue has been exceeded and the queue level is thus reached. The value generated here is used when dynamically creating a temporary queue if no other value is specified in the KDCS call QCRE.
STD	openUTM rejects all additional messages for the queue with a negative return code if the queue level has been reached. Default: STD
WRAP-AROUND	openUTM continues to accept messages for the temporary queue, even if the queue level has already been reached. When writing a message to the queue openUTM deletes the oldest messages in the queue and replaces it with the new one.