Consumes a message previously offered by this source_block object and successfully reserved by the target, transferring ownership to the caller.
virtual message<_Target_type> * consume( runtime_object_identity _MsgId, ITarget<_Target_type> * _PTarget );
The method throws an invalid_argument exception if the parameter _PTarget is NULL.
The method throws a bad_target exception if the parameter _PTarget does not represent the target that called reserve.
The consume method is similar to accept, but must always be preceded by a call to reserve that returned true.