Block until all the elements in this queue are removed. Return 0 on success, and a non-zero value otherwise. Specifically, return e_DISABLED if !isEmpty() && isPopFrontDisabled(). A blocked thread waiting for the queue to empty will return e_DISABLED if disablePopFront is invoked. The behavior is undefined unless the invoker of this method is the single producer.
Declared in <bdlcc_singleproducerqueue.h>
int
waitUntilEmpty() const;