17.2.65. MPI_Comm_group

MPI_Comm_group - Returns the group associated with a communicator.

17.2.65.1. SYNTAX

17.2.65.1.1. C Syntax

#include <mpi.h>

int MPI_Comm_group(MPI_Comm comm, MPI_Group *group)

17.2.65.1.2. Fortran Syntax

USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_COMM_GROUP(COMM, GROUP, IERROR)
     INTEGER COMM, GROUP, IERROR

17.2.65.1.3. Fortran 2008 Syntax

USE mpi_f08
MPI_Comm_group(comm, group, ierror)
     TYPE(MPI_Comm), INTENT(IN) :: comm
     TYPE(MPI_Group), INTENT(OUT) :: group
     INTEGER, OPTIONAL, INTENT(OUT) :: ierror

17.2.65.2. INPUT PARAMETER

  • comm: Communicator.

17.2.65.3. OUTPUT PARAMETERS

  • group: Group in communicator (handle).

  • IERROR: Fortran only: Error status (integer).

17.2.65.4. DESCRIPTION

If the communicator is an intercommunicator (enables communication between two groups of processes), this function returns the local group. To return the remote group, use the MPI_Comm_remote_group function.

17.2.65.5. ERRORS

Almost all MPI routines return an error value; C routines as the value of the function and Fortran routines in the last argument.

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.