Communicator to which attribute is attached (handle).
.TP 1i
keyval
The key value of the deleted attribute (integer).
.SH OUTPUT PARAMETER
.ft R
.TP 1i
IERROR
Fortran only: Error status (integer).
.SH DESCRIPTION
This deprecated routine is not available in C++.
.sp
Note that use of this routine is \fIdeprecated\fP as of MPI-2. Please use MPI_Comm_delete_attr.
.sp
Delete attribute from cache by key. This function invokes the attribute delete function delete_fn specified when the 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.
.SH 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.
.sp
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.
