osx man page for mpi_file_set_atomicity

MPI_File_set_atomicity(3OpenMPI)										  MPI_File_set_atomicity(3OpenMPI)

NAME
       MPI_File_set_atomicity - Sets consistency semantics for data-access operations (collective).

SYNTAX
       C Syntax
	   #include <mpi.h>
	   int MPI_File_set_atomicity(MPI_File fh, int flag)

       Fortran Syntax
	   INCLUDE 'mpif.h'
	   MPI_FILE_SET_ATOMICITY(FH, FLAG, IERROR)
		  INTEGER    FH, FLAG, IERROR

C++ Syntax
       #include <mpi.h>
       void MPI::File::Set_atomicity(bool flag)

INPUT PARAMETERS
       fh	 File handle (handle).

       flag	 true to enable atomic mode, false to enable nonatomic mode (boolean).

OUTPUT PARAMETER
       IERROR	 Fortran only: Error status (integer).

DESCRIPTION
       The  consistency  semantics for data-access operations using the set of file handles created by one collective MPI_File_open is set by col-
       lectively calling MPI_File_set_atomicity. All processes in the group must pass identical values for fh and flag.  If flag is  true,  atomic
       mode is set; if flag is false, nonatomic mode is set.

       The default value on a call to MPI_File_open in Open MPI is true for jobs running on more than one node, false for jobs running on a single
       SMP. For more information, see the MPI-2 standard.

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++ func-
       tions  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.

       Before the error value is returned, the current MPI error handler is called. For MPI I/O function errors, the default error handler is  set
       to  MPI_ERRORS_RETURN. The error handler may be changed with MPI_File_set_errhandler; the predefined error handler MPI_ERRORS_ARE_FATAL may
       be used to make I/O errors fatal. Note that MPI does not guarantee that an MPI program can continue past an error.

Open MPI 1.2							  September 2006				  MPI_File_set_atomicity(3OpenMPI)