Returns the first valid transaction at the head of the output queue referenced by the hObject parameter. If one or more transactions at the head of the queue have been deleted (because their port has been deleted or they have been canceled) this call invisibly dequeues them and returns them to the pool. Therefore it is recommended that this call is used to test a queue before removing the head item (using DequeueOutputTransaction).

LPTRANSACTION QueryOutputTransactionQueue(
    RTHANDLE hObject
);

Parameters

hObject

A handle for either a service or a port.

Return Values

A valid pointer to a TRANSACTION structure, or NULL if queue was empty.

Success.

BAD_POINTER

Failure. To determine the status, call GetLastRtError.

Status

E_CONTEXT 0x0005

The port is being deleted or the service is being uninstalled.

E_EXIST 0x0006

The hObject parameter is not a valid handle.

E_TYPE 0x8002

The hObject parameter is not a handle for a port or a service.

Requirements

See Also

RT Service system calls, DequeueOutputTransaction, TRANSACTION