:ref:`MPI_Comm_free` - Mark a communicator object for deallocation.
#include <mpi.h>
int MPI_Comm_free(MPI_Comm *comm)
USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_COMM_FREE(COMM, IERROR)
INTEGER COMM, IERROR
USE mpi_f08
MPI_Comm_free(comm, ierror)
TYPE(MPI_Comm), INTENT(INOUT) :: comm
INTEGER, OPTIONAL, INTENT(OUT) :: ierror
comm
: Communicator to be destroyed (handle).
ierror
: Fortran only: Error status (integer).
This operation marks the communicator object for deallocation. The handle is set to MPI_COMM_NULL. Any pending operations that use this communicator will complete normally; the object is actually deallocated only if there are no other active references to it. This call applies to intracommunicators and intercommunicators. Upon actual deallocation, the delete callback functions for all cached attributes (see Section 5.7 in the MPI-1 Standard, "Caching") are called in arbitrary order.
Note that it is not defined by the MPI standard what happens if the delete_fn callback invokes other MPI functions. In Open MPI, it is not valid for delete_fn callbacks (or any of their children) to add or delete attributes on the same object on which the delete_fn callback is being invoked.
.. seealso::
* :ref:`MPI_Comm_delete_attr`