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¶

USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_COMM_DELETE_ATTR(COMM, COMM_KEYVAL, IERROR)
	INTEGER	COMM, COMM_KEYVAL, IERROR 

Fortran 2008 Syntax¶

USE mpi_f08
MPI_Comm_delete_attr(comm, comm_keyval, ierror)
	TYPE(MPI_Comm), INTENT(IN) :: comm
	INTEGER, INTENT(IN) :: comm_keyval
	INTEGER, OPTIONAL, INTENT(OUT) :: 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.

NOTES¶

Note that it is not defined by the MPI standard what happens if the delete_fn callback invokes other MPI functions. In Open MPI, it is not valid for delete_fn callbacks (or any of their children) to add or delete attributes on the same object on which the delete_fn callback is being invoked.

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++ functions 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.