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mpi_intercomm_create(3openmpi) [osx man page]

MPI_Intercomm_create(3OpenMPI)											    MPI_Intercomm_create(3OpenMPI)

NAME
MPI_Intercomm_create - Creates an intercommuncator from two intracommunicators. SYNTAX
C Syntax #include <mpi.h> int MPI_Intercomm_create(MPI_Comm local_comm, int local_leader, MPI_Comm peer_comm, int remote_leader, int tag, MPI_Comm *newintercomm) Fortran Syntax INCLUDE 'mpif.h' MPI_INTERCOMM_CREATE(LOCAL_COMM, LOCAL_LEADER, PEER_COMM, REMOTE_LEADER, TAG, NEWINTERCOMM, IERROR) INTEGER LOCAL_COMM, LOCAL_LEADER, PEER_COMM, REMOTE_LEADER INTEGER TAG, NEWINTERCOMM, IERROR C++ Syntax #include <mpi.h> Intercomm Intracomm::Create_intercomm(int local_leader, const Comm& peer_comm, int remote_leader, int tag) const INPUT PARAMTERS
local_comm The communicator containing the process that initiates the inter-communication (handle). local_leader Rank of local group leader in local_comm (integer). peer_comm "Peer" communicator; significant only at the local_leader (handle). remote_leader Rank of remote group leader in peer_comm; significant only at the local_leader (integer). tag Message tag used to identify new intercommunicator (integer). OUTPUT PARAMETERS
newintercomm Created intercommunicator (handle). IERROR Fortran only: Error status (integer). DESCRIPTION
This call creates an intercommunicator. It is collective over the union of the local and remote groups. Processes should provide identical local_comm and local_leader arguments within each group. Wildcards are not permitted for remote_leader, local_leader, and tag. This call uses point-to-point communication with communicator peer_comm, and with tag tag between the leaders. Thus, care must be taken that there be no pending communication on peer_comm that could interfere with this communication. If multiple MPI_Intercomm_creates are being made, 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). NOTES
We recommend using a dedicated peer communicator, such as a duplicate of MPI_COMM_WORLD, to avoid trouble with peer communicators. The MPI 1.1 Standard contains two mutually exclusive comments on the input intracommunicators. One says that their repective groups must be disjoint; the other that the leaders can be the same process. After some discussion by the MPI Forum, it has been decided that the groups must be disjoint. Note that the reason given for this in the standard is not the reason for this choice; rather, the other opera- tions on intercommunicators (like MPI_Intercomm_merge ) do not make sense if the groups are not disjoint. 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++ func- tions 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_Intercomm_merge MPI_Comm_free MPI_Comm_remote_group MPI_Comm_remote_size Open MPI 1.2 September 2006 MPI_Intercomm_create(3OpenMPI)

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MPI_Errhandler_set(3OpenMPI)											      MPI_Errhandler_set(3OpenMPI)

NAME
MPI_Errhandler_set - Sets the error handler for a communicator -- use of this routine is deprecated. SYNTAX
C Syntax #include <mpi.h> int MPI_Errhandler_set(MPI_Comm comm, MPI_Errhandler errhandler) Fortran Syntax INCLUDE 'mpif.h' MPI_ERRHANDLER_SET(COMM, ERRHANDLER, IERROR) INTEGER COMM, ERRHANDLER, IERROR INPUT PARAMETERS
comm Communicator to set the error handler for (handle). errhandler New MPI error handler for communicator (handle). OUTPUT PARAMETER
IERROR Fortran only: Error status (integer). DESCRIPTION
Note that use of this routine is deprecated as of MPI-2. Please use MPI_Comm_set_errhandler instead. This deprecated routine is not available in C++. Associates the new error handler errhandler with communicator comm at the calling process. Note that an error handler is always associated with the communicator. 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++ func- tions 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_create_errhandler MPI_Comm_get_errhandler MPI_Comm_set_errhandler Open MPI 1.2 September 2006 MPI_Errhandler_set(3OpenMPI)
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