Signal1 (MQLONG)

This is an input field that is used only in conjunction with the MQGMO_SET_SIGNAL option; it identifies a signal that is to be delivered when a message is available.

Note:
The data type and usage of this field are determined by the environment; for this reason, applications that you want to port between different environments must not use signals.

The signal completion codes are:

MQEC_MSG_ARRIVED
A suitable message has arrived on the queue. This message has not been reserved for the caller; a second MQGET request must be issued, but another application might retrieve the message before the second request is made.
MQEC_WAIT_INTERVAL_EXPIRED
The specified WaitInterval has expired without a suitable message arriving.
MQEC_WAIT_CANCELED
The wait was canceled for an indeterminate reason (such as the queue manager terminating or the queue being disabled). Reissue the request if you want further diagnosis.
MQEC_Q_MGR_QUIESCING
The wait was canceled because the queue manager has entered the quiescing state (MQGMO_FAIL_IF_QUIESCING was specified on the MQGET call).
MQEC_CONNECTION_QUIESCING
The wait was canceled because the connection has entered the quiescing state (MQGMO_FAIL_IF_QUIESCING was specified on the MQGET call).

The initial value of this field is determined by the environment: