MPIFilereadordered(3OpenMPI) MPIFilereadordered(3OpenMPI)

NAME
       MMPPIIFFiilleerreeaaddoorrddeerreedd  -  Reads  a  file  at  a location specified by a
       shared file pointer (blocking, collective).


SSYYNNTTAAXX
       C Syntax
           #include 
           int MPIFilereadordered(MPIFile fh, void *buf,
                         int count, MPIDatatype datatype,
                         MPIStatus *status)

       Fortran Syntax
           INCLUDE 'mpif.h'
           MPIFILEREADORDERED(FH, BUF, COUNT, DATATYPE,
                         STATUS, IERROR)
                       BUF(*)
                  INTEGER    FH, COUNT, DATATYPE, STATUS(MPISTATUSSIZE), IERROR


CC++++ SSyynnttaaxx
       #include 
       void MPI::File::Readordered(void* buf, int count,
            const MPI::Datatype& datatype, MPI::Status& status)

       void MPI::File::Readordered(void* buf, int count,
            const MPI::Datatype& datatype)


IINNPPUUTT PPAARRAAMMEETTEERRSS
       fh        File handle (handle).

       count     Number of elements in buffer (integer).

       datatype  Data type of each buffer element (handle).


OOUUTTPPUUTT PPAARRAAMMEETTEERRSS
       buf       Initial address of buffer (choice).

       status    Status object (Status).

       IERROR    Fortran only: Error status (integer).


DESCRIPTION
       MPIFilereadordered 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.
       MPIFilereadordered  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.


EERRRROORRSS
       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::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  set
       to   MPIERRORSRETURN.   The   error   handler  may  be  changed  with
       MPIFileseterrhandler;     the     predefined      error      handler
       MPIERRORSAREFATAL  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 MPIFilereadordered(3OpenMPI)