MPI_Intercomm_create(3)

NAME
     MPI_Intercomm_create - Creates an intercommuncator from two
     intracommunicators

SYNOPSIS
     C:

          #include <mpi.h>

          int MPI_Intercomm_create ( local_comm, local_leader,
          peer_comm, remote_leader, tag, comm_out )
          MPI_Comm  local_comm;
          int       local_leader;
          MPI_Comm  peer_comm;
          int       remote_leader;
          int       tag;
          MPI_Comm *comm_out;


     C++:

          #include <mpi.h>

          Intercomm Intracomm::Create_intercomm(
          int               local_leader,
          const Comm&       peer_comm,
          int               remote_leader,
          int               tag) const


     Fortran:

          INCLUDE "mpif.h" (or USE MPI)

          INTEGER local_comm, local_leader, peer_comm, remote_leader,
          tag, newintercomm, ierror

          Call MPI_INTERCOMM_CREATE(local_comm, local_leader, peer_comm,
          remote_leader, tag, newintercomm, ierror)


STANDARDS
     This release implements the MPI 1.2 standard, as documented by the MPI
     Forum in the spring 1997 release of MPI:  A Message Passing Interface
     Standard.

DESCRIPTION
     The MPI_Intercomm_create routine creates an intercommunicator from two
     intracommunicators.  This routine accepts the following parameters:
     local_comm     Specifies a local intracommunicator.

     local_leader   Specifies the rank in the local communicator (local_comm)
                    of the leader (often 0).

     peer_comm      Specifies the remote communicator.

     remote_leader  Specifies the rank in the remote communicator (peer_comm)
                    of the leader (often 0).

     tag            Specifies the message tag to use in constructing the
                    intercommunicator.  If multiple MPI_Intercomm_create
                    routines are being called, they should use different tags
                    (more precisely, they should ensure that the local and
                    remote leaders are using different tags for each
                    MPI_intercomm_create routine).

     comm_out       Returns the created intercommunicator.

     ierror         Specifies the return code value for successful completion,
                    which is in MPI_SUCCESS.  MPI_SUCCESS is defined in the
                    mpif.h file.