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MPI_File_read(3) man page (version 1.2.9)

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NAME

       MPI_File_read  - Reads a file starting at the location specified by the
       individual file pointer (blocking, noncollective).

SYNTAX

       C Syntax
           #include <mpi.h>
           int MPI_File_read(MPI_File fh, void *buf,
                  int count, MPI_Datatype datatype, MPI_Status *status)

       Fortran Syntax
           INCLUDE 'mpif.h'
           MPI_FILE_READ( 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(void* buf, int count,
            const MPI::Datatype& datatype, MPI::Status& status)

       void MPI::File::Read(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 (integer).

       status    Status object (status).

       IERROR    Fortran only: Error status (integer).

DESCRIPTION

       MPI_File_read attempts to read from the file associated with fh (at the
       current  individual  file  pointer position maintained by the system) a
       total number of count data items having datatype type into  the  user's
       buffer buf.  The data is taken out of those parts of the file specified
       by the current view. MPI_File_read stores the number of data-type  ele-
       ments  actually  read  in status.  All other fields of status are unde-
       fined.

       It is erroneous to call this function if MPI_MODE_SEQUENTIAL  mode  was
       specified when the file was opened.

       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_read(3OpenMPI)

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