.TH MPI_Win_create_dynamic 3 "11/12/2019" " " "MPI"

.SH NAME

MPI_Win_create_dynamic \-  Create an MPI Window object for one-sided communication.  This window allows memory to be dynamically exposed and un-exposed for RMA operations. 

.SH SYNOPSIS

.nf

int MPI_Win_create_dynamic(MPI_Info info, MPI_Comm comm, MPI_Win * win)

.fi

This is a collective call executed by all processes in the group of comm. It

returns a window win without memory attached. Existing process memory can be

attached as described below. This routine returns a window object that can be

used by these processes to perform RMA operations on attached memory. Because

this window has special properties, it will sometimes be referred to as a

dynamic window.  The info argument can be used to specify hints similar to the

info argument for 

.I MPI_Win_create

\&.

In the case of a window created with 

.I MPI_Win_create_dynamic

, the target_disp

for all RMA functions is the address at the target; i.e., the effective

window_base is 

.I MPI_BOTTOM

and the disp_unit is one. For dynamic windows, the

target_disp argument to RMA communication operations is not restricted to

non-negative values. Users should use 

.I MPI_Get_address

at the target process to

determine the address of a target memory location and communicate this address

to the origin process.

.SH INPUT PARAMETERS

.PD 0

.TP

.B info 

- info argument (handle)

.PD 1

.PD 0

.TP

.B comm 

- communicator (handle)

.PD 1

.SH OUTPUT PARAMETERS

.PD 0

.TP

.B win 

- window object returned by the call (handle)

.PD 1

.SH NOTES

Users are cautioned that displacement arithmetic can overflow in variables of

type 

.I MPI_Aint

and result in unexpected values on some platforms. This issue may

be addressed in a future version of MPI.

Memory in this window may not be used as the target of one-sided accesses in

this window until it is attached using the function 

.I MPI_Win_attach

\&.

That is, in

addition to using 

.I MPI_Win_create_dynamic

to create an MPI window, the user must

use 

.I MPI_Win_attach

before any local memory may be the target of an MPI RMA

operation. Only memory that is currently accessible may be attached.

.SH THREAD AND INTERRUPT SAFETY

This routine is thread-safe.  This means that this routine may be

safely used by multiple threads without the need for any user-provided

thread locks.  However, the routine is not interrupt safe.  Typically,

this is due to the use of memory allocation routines such as 

.I malloc

or other non-MPICH runtime routines that are themselves not interrupt-safe.

.SH NOTES FOR FORTRAN

All MPI routines in Fortran (except for 

.I MPI_WTIME

and 

.I MPI_WTICK

) have

an additional argument 

.I ierr

at the end of the argument list.  

.I ierr

is an integer and has the same meaning as the return value of the routine

in C.  In Fortran, MPI routines are subroutines, and are invoked with the

.I call

statement.

All MPI objects (e.g., 

.I MPI_Datatype

, 

.I MPI_Comm

) are of type 

.I INTEGER

in Fortran.

.SH ERRORS

All MPI routines (except 

.I MPI_Wtime

and 

.I MPI_Wtick

) return an error value;

C routines as the value of the function and Fortran routines in the last

argument.  Before the value is returned, the current MPI error handler is

called.  By default, this error handler aborts the MPI job.  The error handler

may be changed with 

.I MPI_Comm_set_errhandler

(for communicators),

.I MPI_File_set_errhandler

(for files), and 

.I MPI_Win_set_errhandler

(for

RMA windows).  The MPI-1 routine 

.I MPI_Errhandler_set

may be used but

its use is deprecated.  The predefined error handler

.I MPI_ERRORS_RETURN

may be used to cause error values to be returned.

Note that MPI does 

.B not

guarentee that an MPI program can continue past

an error; however, MPI implementations will attempt to continue whenever

possible.

.PD 0

.TP

.B MPI_SUCCESS 

- No error; MPI routine completed successfully.

.PD 1

.PD 0

.TP

.B MPI_ERR_ARG 

- Invalid argument.  Some argument is invalid and is not

identified by a specific error class (e.g., 

.I MPI_ERR_RANK

).

.PD 1

.PD 0

.TP

.B MPI_ERR_COMM 

- Invalid communicator.  A common error is to use a null

communicator in a call (not even allowed in 

.I MPI_Comm_rank

).

.PD 1

.PD 0

.TP

.B MPI_ERR_INFO 

- Invalid Info 

.PD 1

.PD 0

.TP

.B MPI_ERR_OTHER 

- Other error; use 

.I MPI_Error_string

to get more information

about this error code. 

.PD 1

.PD 0

.TP

.B MPI_ERR_SIZE 

- 

.PD 1

.SH SEE ALSO

MPI_Win_attach MPI_Win_detach MPI_Win_allocate MPI_Win_allocate_shared MPI_Win_create MPI_Win_free

.br