[Boost-users] [mpi] potentially blocking send - require blocking

The boost::mpi documentation for send() is: "This routine executes a potentially blocking send" This differs from MPI_Send() "This routine will block until the message is sent to the destination." I am developing an application which requires the code not to progress until the communication is complete. In which situations does "potentially blocking" apply? And, is there a way of guaranteeing it is complete, the equivalent of MPI_Wait() for MPI_Isend()? Regards, Dave