MPI_File_read_ordered(3) Open MPI MPI_File_read_ordered(3)NAMEMPI_File_read_ordered - Reads a file at a location specified by a
shared file pointer (blocking, collective).
SYNTAX
C Syntax
#include <mpi.h>
int MPI_File_read_ordered(MPI_File fh, void *buf,
int count, MPI_Datatype datatype,
MPI_Status *status)
Fortran Syntax
INCLUDE 'mpif.h'
MPI_FILE_READ_ORDERED(FH, BUF, COUNT, DATATYPE,
STATUS, IERROR)
<type> BUF(*)
INTEGER FH, COUNT, DATATYPE, STATUS(MPI_STATUS_SIZE), IERROR
C++ Syntax
#include <mpi.h>
void MPI::File::Read_ordered(void* buf, int count,
const MPI::Datatype& datatype, MPI::Status& status)
void MPI::File::Read_ordered(void* buf, int count,
const MPI::Datatype& datatype)
INPUT PARAMETERS
fh File handle (handle).
count Number of elements in buffer (integer).
datatype Data type of each buffer element (handle).
OUTPUT PARAMETERS
buf Initial address of buffer (choice).
status Status object (Status).
IERROR Fortran only: Error status (integer).
DESCRIPTIONMPI_File_read_ordered is a collective routine. This routine must be
called by all processes in the communicator group associated with the
file handle fh. Each process may pass different argument values for
the datatype and count arguments. Each process attempts to read, from
the file associated with fh, a total number of count data items having
datatype type into the user's buffer buf. For each process, the loca‐
tion in the file at which data is read is the position at which the
shared file pointer would be after all processes whose ranks within the
group are less than that of this process had read their data.
MPI_File_read_ordered returns the actual number of datatype elements
read in status. The shared file pointer is updated by the amounts of
data requested by all processes of the group.
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.
1.7.4 Feb 04, 2014 MPI_File_read_ordered(3)
