NAME¶
MPI_Comm_free - Mark a communicator object for deallocation.
C Syntax¶
#include <mpi.h>
int MPI_Comm_free(MPI_Comm *comm)
Fortran Syntax¶
INCLUDE 'mpif.h'
MPI_COMM_FREE(COMM, IERROR)
INTEGER COMM, IERROR
C++ Syntax¶
#include <mpi.h>
void Comm::Free()
- comm
- Communicator to be destroyed (handle).
OUTPUT PARAMETER¶
- IERROR
- Fortran only: Error status (integer).
DESCRIPTION¶
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.
NOTES¶
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.
ERRORS¶
Almost all MPI routines return an error value; C routines as the value of the
function and Fortran routines in the last argument. C++ functions do not
return errors. If the default error handler is set to
MPI::ERRORS_THROW_EXCEPTIONS, then on error the C++ exception mechanism will
be used to throw an MPI::Exception object.
Before the error value is returned, the current MPI error handler
is called. By default, this error handler aborts the MPI job, except for I/O
function errors. The error handler may be changed with
MPI_Comm_set_errhandler; the predefined error handler MPI_ERRORS_RETURN may
be used to cause error values to be returned. Note that MPI does not
guarantee that an MPI program can continue past an error.
SEE ALSO¶
MPI_Comm_delete_attr