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MPI_Comm_get_attr(3) man page (version 1.2.9)

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NAME

       MPI_Comm_get_attr - Retrieves attribute value by key.

SYNTAX


C Syntax

       #include <mpi.h>
       int MPI_Comm_get_attr(MPI_Comm comm, int comm_keyval,
            void *attribute_val, int *flag)

Fortran Syntax (see FORTRAN 77 NOTES)

       INCLUDE 'mpif.h'
       MPI_COMM_GET_ATTR(COMM, COMM_KEYVAL, ATTRIBUTE_VAL, IERROR)
            INTEGER   COMM, COMM_KEYVAL, IERROR
            INTEGER(KIND=MPI_ADDRESS_KIND) ATTRIBUTE_VAL
            LOGICAL FLAG

C++ Syntax

       #include <mpi.h>
       bool MPI::Comm::Get_attr(int comm_keyval, void* attribute_val)
            const

INPUT PARAMETERS

       comm      Communicator to which the attribute is attached (handle).

       comm_keyval
                 Key value (integer).

OUTPUT PARAMETER

       attribute_val
                 Attribute value, unless flag = false.

       flag      False if no attribute is associated with the key (logical).

       IERROR    Fortran only: Error status (integer).

DESCRIPTION

       MPI_Comm_get_attr  retrieves  an  attribute  value  by key. The call is
       erroneous if there is no key with value keyval. On the other hand,  the
       call  is  correct if the key value exists, but no attribute is attached
       on comm for that key; in that case, the call returns flag =  false.  In
       particular, MPI_KEYVAL_INVALID is an erroneous key value.

       This  function  replaces  MPI_Attr_get, the use of which is deprecated.
       The C binding  is  identical.  The  Fortran  binding  differs  in  that
       attribute_val is an address-sized integer.

FORTRAN 77 NOTES

       The   MPI   standard   prescribes   portable  Fortran  syntax  for  the
       ATTRIBUTE_VAL argument only for Fortran 90. Sun FORTRAN  77  users  may
       use the non-portable syntax

       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_get_attr(3OpenMPI)

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