plucky (3) MPI_Comm_delete_attr.openmpi.3.gz
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
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 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:
• MPI_Comm_create_errhandler then MPI_Comm_set_errhandler
• MPI_File_create_errhandler then MPI_File_set_errhandler
• MPI_Session_create_errhandler then MPI_Session_set_errhandler or at MPI_Session_init
• MPI_Win_create_errhandler then MPI_Win_set_errhandler
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.
COPYRIGHT
2003-2025, The Open MPI Community
Feb 17, 2025 MPI_COMM_DELETE_ATTR(3)