17.2.436. MPI_Win_create_keyval

MPI_Win_create_keyval — Creates a keyval for a window.

17.2.436.1. SYNTAX

17.2.436.1.1. C Syntax

#include <mpi.h>

int MPI_Win_create_keyval(MPI_Win_copy_attr_function *win_copy_attr_fn,
     MPI_Win_delete_attr_function *win_delete_attr_fn,
     int *win_keyval, void *extra_state)

17.2.436.1.2. Fortran Syntax

USE MPI
! or the older form: INCLUDE 'mpif.h'
MPI_WIN_CREATE_KEYVAL(WIN_COPY_ATTR_FN, WIN_DELETE_ATTR_FN,
     WIN_KEYVAL, EXTRA_STATE, IERROR)
     EXTERNAL WIN_COPY_ATTR_FN, WIN_DELETE_ATTR_FN
     INTEGER WIN_KEYVAL, IERROR
     INTEGER(KIND=MPI_ADDRESS_KIND) EXTRA_STATE

17.2.436.1.3. Fortran 2008 Syntax

USE mpi_f08
MPI_Win_create_keyval(win_copy_attr_fn, win_delete_attr_fn, win_keyval,
             extra_state, ierror)
     PROCEDURE(MPI_Win_copy_attr_function) :: win_copy_attr_fn
     PROCEDURE(MPI_Win_delete_attr_function) :: win_delete_attr_fn
     INTEGER, INTENT(OUT) :: win_keyval
     INTEGER(KIND=MPI_ADDRESS_KIND), INTENT(IN) :: extra_state
     INTEGER, OPTIONAL, INTENT(OUT) :: ierror

17.2.436.2. INPUT PARAMETERS

  • win_copy_attr_fn: Copy callback function for win_keyval (function).

  • win_delete_attr_fn: Delete callback function for win_keyval (function).

  • extra_state: Extra state for callback functions.

17.2.436.3. OUTPUT PARAMETERS

  • win_keyval: Key value for future access (integer).

  • ierror: Fortran only: Error status (integer).

17.2.436.4. DESCRIPTION

The argument win_copy_attr_fn may be specified as MPI_WIN_NULL_COPY_FN or MPI_WIN_DUP_FN from either C or Fortran. MPI_WIN_NULL_COPY_FN is a function that serves only to return flag = 0 and MPI_SUCCESS. MPI_WIN_DUP_FN is a simple-minded copy function that sets flag = 1, returns the value of attribute_val_in in attribute_val_out, and returns MPI_SUCCESS.

The argument win_delete_attr_fn may be specified as MPI_WIN_NULL_DELETE_FN from either C or Fortran. MPI_WIN_NULL_DELETE_FN is a function that serves only to return MPI_SUCCESS.

The C callback functions are:

typedef int MPI_Win_copy_attr_function(MPI_Win oldwin, int win_keyval,
             void *extra_state, void *attribute_val_in,
             void *attribute_val_out, int *flag);

typedef int MPI_Win_delete_attr_function(MPI_Win win, int win_keyval,
             void *attribute_val, void *extra_state);

The Fortran callback functions are:

SUBROUTINE WIN_COPY_ATTR_FN(OLDWIN, WIN_KEYVAL, EXTRA_STATE,
     ATTRIBUTE_VAL_IN, ATTRIBUTE_VAL_OUT, FLAG, IERROR)
     INTEGER OLDWIN, WIN_KEYVAL, IERROR
     INTEGER(KIND=MPI_ADDRESS_KIND) EXTRA_STATE, ATTRIBUTE_VAL_IN,
             ATTRIBUTE_VAL_OUT
     LOGICAL FLAG

SUBROUTINE WIN_DELETE_ATTR_FN(WIN, WIN_KEYVAL, ATTRIBUTE_VAL,
     EXTRA_STATE, IERROR)
     INTEGER WIN, WIN_KEYVAL, IERROR
     INTEGER(KIND=MPI_ADDRESS_KIND) ATTRIBUTE_VAL, EXTRA_STATE

17.2.436.5. ERRORS

Almost all MPI routines return an error value; C routines as the return result of the function and Fortran routines in the last argument.

Before the error value is returned, the current MPI error handler associated with the communication object (e.g., communicator, window, file) is called. If no communication object is associated with the MPI call, then the call is considered attached to MPI_COMM_SELF and will call the associated MPI error handler. When MPI_COMM_SELF is not initialized (i.e., before MPI_Init/MPI_Init_thread, after MPI_Finalize, or when using the Sessions Model exclusively) the error raises the initial error handler. The initial error handler can be changed by calling MPI_Comm_set_errhandler on MPI_COMM_SELF when using the World model, or the mpi_initial_errhandler CLI argument to mpiexec or info key to MPI_Comm_spawn/MPI_Comm_spawn_multiple. If no other appropriate error handler has been set, then the MPI_ERRORS_RETURN error handler is called for MPI I/O functions and the MPI_ERRORS_ABORT error handler is called for all other MPI functions.

Open MPI includes three predefined error handlers that can be used:

  • MPI_ERRORS_ARE_FATAL Causes the program to abort all connected MPI processes.

  • MPI_ERRORS_ABORT An error handler that can be invoked on a communicator, window, file, or session. When called on a communicator, it acts as if MPI_Abort was called on that communicator. If called on a window or file, acts as if MPI_Abort was called on a communicator containing the group of processes in the corresponding window or file. If called on a session, aborts only the local process.

  • MPI_ERRORS_RETURN Returns an error code to the application.

MPI applications can also implement their own error handlers by calling:

Note that MPI does not guarantee that an MPI program can continue past an error.

See the MPI man page for a full list of MPI error codes.

See the Error Handling section of the MPI-3.1 standard for more information.