WaitInterval (MQLONG)

This is the approximate time, expressed in milliseconds, that the MQGET call waits for a suitable message to arrive (that is, a message satisfying the selection criteria specified in the MsgDesc parameter of the MQGET call.

Important: There is no wait, or delay, if a suitable message is available immediately.

See the MsgId field described in MQMD - Message descriptor for more details). If no suitable message has arrived after this time has elapsed, the call completes with MQCC_FAILED and reason code MQRC_NO_MSG_AVAILABLE.

On z/OS®, the period of time that the MQGET call actually waits is affected by system loading and work-scheduling considerations, and can vary between the value specified for WaitInterval and approximately 250 milliseconds greater than WaitInterval.

WaitInterval is used in conjunction with the MQGMO_WAIT or MQGMO_SET_SIGNAL option. It is ignored if neither of these is specified. If one of these is specified, WaitInterval must be greater than or equal to zero, or the following special value:

MQWI_UNLIMITED: Unlimited wait interval.

The initial value of this field is 0.