:ref:`MPI_Mrecv` |mdash| Blocking receive for a matched message
#include <mpi.h>
int MPI_Mrecv(void *buf, int count, MPI_Datatype type,
MPI_Message *message, MPI_Status *status)
USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_MRECV(BUF, COUNT, DATATYPE, MESSAGE, STATUS, IERROR)
<type> BUF(*)
INTEGER COUNT, DATATYPE, MESSAGE
INTEGER STATUS(MPI_STATUS_SIZE), IERROR
USE mpi_f08
MPI_Mrecv(buf, count, datatype, message, status, ierror)
TYPE(*), DIMENSION(..) :: buf
INTEGER, INTENT(IN) :: count
TYPE(MPI_Datatype), INTENT(IN) :: datatype
TYPE(MPI_Message), INTENT(INOUT) :: message
TYPE(MPI_Status) :: status
INTEGER, OPTIONAL, INTENT(OUT) :: ierror
count
: Number of elements to receive (nonnegative integer).datatype
: Datatype of each send buffer element (handle).message
: Message (handle).
buf
: Initial address of receive buffer (choice).status
: Status object (status).ierror
: Fortran only: Error status (integer).
The functions :ref:`MPI_Mrecv` and :ref:`MPI_Imrecv` receive messages that have been previously matched by a matching probe.
If :ref:`MPI_Mrecv` is called with MPI_MESSAGE_NULL
as the message argument,
the call returns immediately with the status object set to source =
MPI_PROC_NULL
, tag = MPI_ANY_TAG
, and count = 0, as if a receive
from MPI_PROC_NULL
was issued.
If your application does not need to examine the status field, you
can save resources by using the predefined constant
MPI_STATUS_IGNORE
as a special value for the status argument.
Note that per the "Return Status" section in the "Point-to-Point
Communication" chapter in the MPI Standard, MPI errors on messages received
by :ref:`MPI_Mrecv` do not set the status.MPI_ERROR
field in the
returned status. The error code is always passed to the back-end
error handler and may be passed back to the caller through the return
value of :ref:`MPI_Mrecv` if the back-end error handler returns it.
The pre-defined MPI error handler MPI_ERRORS_RETURN
exhibits this
behavior, for example.
.. seealso::
* :ref:`MPI_Mprobe`
* :ref:`MPI_Improbe`
* :ref:`MPI_Probe`
* :ref:`MPI_Iprobe`
* :ref:`MPI_Imrecv`
* :ref:`MPI_Cancel`