The setException() Function
RWTIOUEscrow has two versions of the setException() function. Both indicate whether or not the operation failed to produce a result due to an error condition. One version of the function accepts a reference to an instance of the base exception class, RWTHRxmsg. The other version accepts an RWCString message that is used internally to initialize an RWTHRxmsg instance. In either case, these functions:
Release threads that are waiting for a result. Cause the exception to be rethrown in those threads. 
