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MPI_File_iread(3) man page (version 1.3.4)

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NAME

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

SYNTAX

       C Syntax
           #include <mpi.h>
           int MPI_File_iread(MPI_File fh, void  *buf, int  count,
                  MPI_Datatype  datatype, MPI_Request  *request)

       Fortran Syntax
           INCLUDE 'mpif.h'
           MPI_FILE_IREAD(FH, BUF, COUNT, DATATYPE, REQUEST, IERROR)
                 <type>         BUF(*)
                 INTEGER        FH, COUNT, DATATYPE, REQUEST, IERROR

C++ Syntax

       #include <mpi.h>
       MPI::Request MPI::File::Iread(void* buf, int count,
            const MPI::Datatype& datatype)

INPUT/OUTPUT PARAMETER

       fh        File handle (handle).

INPUT PARAMETERS

       count     Number of elements in the buffer (integer).

       datatype  Data type of each buffer element (handle).

OUTPUT PARAMETERS

       buf       Initial address of buffer (choice).

       request   Request object (handle).

       IERROR    Fortran only: Error status (integer).

DESCRIPTION

       MPI_File_iread is a nonblocking version of MPI_File_read.  It  attempts
       to read from the file associated with fh at the current individual file
       pointer position maintained by the system in which a  total  number  of
       count  data items having datatype type  are read into the user's buffer
       buf.  The data is taken out of those parts of the file specified by the
       current  view.  MPI_File_iread  stores the number of data-type elements
       actually read in status.  All other fields of status are undefined.  It
       is  erroneous  to  call  this  function if MPI_MODE_SEQUENTIAL mode was
       specified when the file was opened.

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  does not guarantee that an MPI program can continue past an error.

1.3.4                            Nov 11, 2009                MPI_File_iread(3)

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