Retrieves messages from a named pipe local buffer.
function UnpackMessage: variant; overload;
UnpackMessage function is used to retrieve messages from a named pipe local buffer.
UnpackMessage is desined to work only with the Oracle DBMS_PIPE communication package which is the case only if TOraAlerter.EventType property has been set to etPipe.
An implementation with the parameter will return True if the Item parameter holds not Null variant value or False otherwise.