mpi_comm_delete_attr(3openmpi) [osx man page]

MPI_Comm_delete_attr(3OpenMPI)											    MPI_Comm_delete_attr(3OpenMPI)

NAME

       MPI_Comm_delete_attr - Deletes attribute value associated with a key.

SYNTAX

C Syntax
       #include <mpi.h>
       int MPI_Comm_delete_attr(MPI_Comm comm, int comm_keyval)

Fortran Syntax
       INCLUDE 'mpif.h'
       MPI_Comm_delete_attr(COMM, COMM_KEYVAL, IERROR)
	    INTEGER   COMM, COMM_KEYVAL, IERROR

C++ Syntax
       #include <mpi.h>
       void MPI::Comm::Delete_attr(int comm_keyval)

INPUT
/OUTPUT PARAMETER
       comm	 Communicator from which the attribute is deleted (handle).

INPUT PARAMETER

       comm_keyval
		 Key value (integer).

OUTPUT PARAMETER

       IERROR	 Fortran only: Error status (integer).

DESCRIPTION

       MPI_Comm_delete_attr  deletes  an attribute from cache by key. This function invokes the attribute delete function delete_fn specified when
       the comm_keyval was created. The call will fail if the delete_fn function returns an error code other than MPI_SUCCESS.

       Whenever a communicator is replicated using the function MPI_Comm_dup, all callback copy functions for attributes that  are  currently  set
       are  invoked  (in  arbitrary order). Whenever a communicator is deleted using the function MPI_Comm_free, all callback delete functions for
       attributes that are currently set are invoked.

       This function is the same as MPI_Attr_delete but is needed to match the communicator-specific functions introduced in the  MPI-2  standard.
       The use of MPI_Attr_delete is deprecated.

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.

Open MPI 1.2							  September 2006				    MPI_Comm_delete_attr(3OpenMPI)

MPI_Comm_dup(3OpenMPI)													    MPI_Comm_dup(3OpenMPI)

NAME

       MPI_Comm_dup  -	Duplicates an existing communicator with all its cached information.

SYNTAX

C Syntax
       #include <mpi.h>
       int MPI_Comm_dup(MPI_Comm comm, MPI_Comm *newcomm)

Fortran Syntax
       INCLUDE 'mpif.h'
       MPI_COMM_DUP(COMM, NEWCOMM, IERROR)
	    INTEGER   COMM, NEWCOMM, IERROR

C++ Syntax
       #include <mpi.h>
       Intracomm Intracomm::Dup() const

       Intercomm Intercomm::Dup() const

INPUT PARAMETER

       comm	 Communicator (handle).

OUTPUT PARAMETERS

       newcomm	 Copy of comm (handle).

       IERROR	 Fortran only: Error status (integer).

DESCRIPTION

       MPI_Comm_dup  duplicates  the existing communicator comm with associated key values. For each key value, the respective copy callback func-
       tion determines the attribute value associated with this key in the new communicator; one particular action that a copy callback  may  take
       is to delete the attribute from the new communicator. Returns in newcomm a new communicator with the same group, any copied cached informa-
       tion, but a new context (see Section 5.7.1 of the MPI-1 Standard, "Functionality").

NOTES

       This operation is used to provide a parallel library call with a duplicate communication space that has the same properties as the original
       communicator.  This  includes  any attributes (see below) and topologies (see Chapter 6, "Process Topologies," in the MPI-1 Standard). This
       call is valid even if there are pending point-to-point communications involving the communicator comm. A  typical  call	might  involve	an
       MPI_Comm_dup at the beginning of the parallel call, and an MPI_Comm_free of that duplicated communicator at the end of the call. Other mod-
       els of communicator management are also possible.

       This call applies to both intra- and intercommunicators.

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.

Open MPI 1.2							  September 2006					    MPI_Comm_dup(3OpenMPI)