NAME

       MPI_Win_create -  Specifies an window accessible by remote processes

SYNOPSIS

       #include <mpi.h>
       int
       MPI_Win_create(void *base, MPI_Aint size, int disp_unit,
                      MPI_Info info, MPI_Comm comm, MPI_Win *newwin)

INPUT PARAMETERS

       base   - initial address of window (choice)
       size   - size of window in bytes (nonnegative integer)
       disp_unit
              - local unit size for displacements, in bytes (positive integer)
       info   - info argument (handle)
       comm   - communicator (handle)
       newwin - window object returned by the call (handle)

NOTES

       Common  choices  for  disp_unit  are 1 (no scaling), and (in C syntax) sizeof(type), for a
       window that consists of an array of elements of type type. The later choice will allow one
       to  use array indices in RMA calls, and have those scaled correctly to byte displacements,
       even in a heterogeneous environment. (  End  of  advice  to  users.)   The  info  argument
       provides optimization hints to the runtime about the expected usage pattern of the window.

       The  various  processes  in  the  group  of  comm  may specify completely different target
       windows, in location, size, displacement units and info arguments. As long as all the get,
       put  and accumulate accesses to a particular process fit their specific target window this
       should pose no problem. The same area in memory  may  appear  in  multiple  windows,  each
       associated with a different window object. However, concurrent communications to distinct,
       overlapping windows may lead to erroneous results.

NOTES FOR FORTRAN

       All MPI routines in Fortran (except for MPI_WTIME  and  MPI_WTICK  )  have  an  additional
       argument  ierr  at  the  end  of  the  argument list.  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 call statement.

       All MPI objects (e.g., MPI_Datatype , MPI_Comm ) are of type INTEGER in Fortran.

USAGE WITH IMPI EXTENSIONS

       The  IMPI  standard  only supports MPI-1 functions.  Hence, this function is currently not
       designed to operate within an IMPI job.

ERRORS

       If an error occurs in an MPI function, the current MPI error handler is called  to  handle
       it.   By default, this error handler aborts the MPI job.  The error handler may be changed
       with MPI_Errhandler_set ; the predefined error handler MPI_ERRORS_RETURN may  be  used  to
       cause  error values to be returned (in C and Fortran; this error handler is less useful in
       with the C++ MPI bindings.   The  predefined  error  handler  MPI::ERRORS_THROW_EXCEPTIONS
       should  be  used in C++ if the error value needs to be recovered).  Note that MPI does not
       guarantee that an MPI program can continue past an error.

       All MPI routines (except MPI_Wtime and MPI_Wtick ) return an error value;  C  routines  as
       the value of the function and Fortran routines in the last argument.  The C++ bindings for
       MPI do not return error  values;  instead,  error  values  are  communicated  by  throwing
       exceptions of type MPI::Exception (but not by default).  Exceptions are only thrown if the
       error value is not MPI::SUCCESS .

       Note that if the MPI::ERRORS_RETURN handler is set in C++, while MPI functions will return
       upon an error, there will be no way to recover what the actual error value was.
       MPI_SUCCESS
              - No error; MPI routine completed successfully.
       MPI_ERR_COMM
              -  Invalid  communicator.   A  common error is to use a null communicator in a call
              (not even allowed in MPI_Comm_rank ).
       MPI_ERR_ARG
              - Invalid argument.  Some argument is invalid and is not identified by  a  specific
              error class.  This is typically a NULL pointer or other such error.
       MPI_ERR_OTHER
              - Other error; use MPI_Error_string to get more information about this error code.
       MPI_ERR_INTERN
              - An internal error has been detected.  This is fatal.  Please send a bug report to
              the LAM mailing list (see http://www.lam-mpi.org/contact.php ).

SEE ALSO

       MPI_Put(3),   MPI_Get(3),   MPI_Accumulate(3),   MPI_Win_start(3),    MPI_Win_complete(3),
       MPI_Win_fence(3),     MPI_Win_free(3),     MPI_Win_get_group(3),     MPI_Win_get_group(3),
       MPI_Win_wait(3)

MORE INFORMATION

       For more information, please see the official MPI Forum web site, which contains the  text
       of both the MPI-1 and MPI-2 standards.  These documents contain detailed information about
       each MPI function (most of which is not duplicated in these man pages).

       http://www.mpi-forum.org/

LOCATION

       wcreate.c