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MPI_File_read_ordered(3) man page (version 1.3.4)

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NAME

       MPI_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).

DESCRIPTION

       MPI_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.

       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.

1.3.4                            Nov 11, 2009         MPI_File_read_ordered(3)

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