NAME
MMPPIIFFiilleesseettaattoommiicciittyy - Sets consistency semantics for data-access
operations (collective). SSYYNNTTAAXX C Syntax#include
int MPIFilesetatomicity(MPIFile fh, int flag) Fortran Syntax INCLUDE 'mpif.h'MPIFILESETATOMICITY(FH, FLAG, IERROR)
INTEGER FH, FLAG, IERROR
CC++++ SSyynnttaaxx#include
void MPI::File::Setatomicity(bool flag) IINNPPUUTT PPAARRAAMMEETTEERRSS fh File handle (handle). flag ttrruuee to enable atomic mode, ffaallssee to enable nonatomic mode (boolean). OOUUTTPPUUTT PPAARRAAMMEETTEERRIERROR Fortran only: Error status (integer).
DESCRIPTION
The consistency semantics for data-access operations using the set of
file handles created by one collective MPIFileopen is set by collec-
tively calling MPIFilesetatomicity. 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 MPIFileopen in Open MPI is true for jobs running on more than one node, false for jobs running on a singleSMP. For more information, see the MPI-2 standard.
EERRRROORRSS Almost all MPI routines return an error value; C routines as the valueof the function and Fortran routines in the last argument. C++ func-
tions do not return errors. If the default error handler is set toMPI::ERRORSTHROWEXCEPTIONS, 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 setto MPIERRORSRETURN. The error handler may be changed with
MPIFileseterrhandler; the predefined error handlerMPIERRORSAREFATAL 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 2006MPIFilesetatomicity(3OpenMPI)