MPI_Keyval_free(3) Open MPI MPI_Keyval_free(3)
NAME
MPI_Keyval_free - Frees attribute key for communicator cache attribute
-- use of this routine is deprecated.
SYNTAX
C Syntax
#include <mpi.h>
int MPI_Keyval_free(int *keyval)
Fortran Syntax
INCLUDE 'mpif.h'
MPI_KEYVAL_FREE(KEYVAL, IERROR)
INTEGER KEYVAL, IERROR
INPUT PARAMETER
keyval Frees the integer key value (integer).
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_free_keyval instead.
This deprecated routine is not available in C++.
Frees an extant attribute key. This function sets the value of keyval
to MPI_KEYVAL_INVALID. Note that it is not erroneous to free an attri-
bute key that is in use, because the actual free does not transpire un-
til after all references (in other communicators on the process) to the
key have been freed. These references need to be explicitly freed by
the program, either via calls to MPI_Attr_delete that free one attri-
bute instance, or by calls to MPI_Comm_free that free all attribute in-
stances associated with the freed communicator.
NOTE
Key values are global (they can be used with any and all communica-
tors).
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_Keyval_create
MPI_Comm_free_keyval
4.1.2 Nov 24, 2021 MPI_Keyval_free(3)
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