MPI_Group_union

Produces a group by combining two groups

Synopsis

#include "mpi.h"
int MPI_Group_union ( MPI_Group group1, MPI_Group group2, 
                     MPI_Group *group_out )

Input Parameters

	group1	first group (handle)
	group2	second group (handle)

Output Parameter

newgroup

union group (handle)

Notes for Fortran

All MPI routines in Fortran (except for MPI_WTIME and MPI_WTICK) have an additional argument ierr at the end of the argument list. ierr is an integer and has the same meaning as the return value of the routine in C. In Fortran, MPI routines are subroutines, and are invoked with the call statement.

All MPI objects (e.g., MPI_Datatype, MPI_Comm) are of type INTEGER in Fortran.

Errors

All MPI routines (except MPI_Wtime and MPI_Wtick) return an error value; C routines as the value of the function and Fortran routines in the last argument. Before the value is returned, the current MPI error handler is called. By default, this error handler aborts the MPI job. The error handler may be changed with MPI_Errhandler_set; the predefined error handler MPI_ERRORS_RETURN may be used to cause error values to be returned. Note that MPI does not guarentee that an MPI program can continue past an error.

MPI_SUCCESS

No error; MPI routine completed successfully.

MPI_ERR_GROUP

Null group passed to function.

MPI_ERR_INTERN

This error is returned when some part of the MPICH implementation is unable to acquire memory.

See Also

MPI_Group_free

Location:group_union.c