MPIFilereadatallbegin(3OpenMPI) MPIFilereadatallbegin(3OpenMPI)

NAME
       MMPPIIFFiilleerreeaaddaattaallllbbeeggiinn  - Reads a file at explicitly specified off-
       sets; beginning part of a split collective routine (nonblocking).


SSYYNNTTAAXX
       C Syntax
           #include 
           int MPIFilereadatallbegin(MPIFile fh, MPIOffset
            offset, void *buf, int count, MPIDatatype
            datatype)

       Fortran Syntax (see FORTRAN 77 NOTES)
           INCLUDE 'mpif.h'
           MPIFILEREADATALLBEGIN(FH, OFFSET, BUF,
            COUNT, DATATYPE, IERROR)
                  BUF(*)
                 INTEGER   FH, COUNT, DATATYPE, IERROR
                 INTEGER(KIND=MPIOFFSETKIND) OFFSET


CC++++ SSyynnttaaxx
       #include 
       void MPI::File::Readatallbegin(MPI::Offset offset, void* buf,
            int count, const MPI::Datatype& datatype)


IINNPPUUTT PPAARRAAMMEETTEERRSS
       fh        File handle (handle).

       offset    File offset (integer).

       count     Number of elements in buffer (integer).

       datatype  Data type of each buffer element.


OOUUTTPPUUTT PPAARRAAMMEETTEERRSS
       buf       Initial address of buffer (choice).

       IERROR    Fortran only: Error status (integer).


DESCRIPTION
       MPIFilereadatallbegin is the beginning part of a split  collective
       routine  that attempts to read from the file associated with fh (at the
       offset position) a total number of count  data  items  having  datatype
       type into the user's buffer buf.  The offset is in etype units relative
       to the current view. That is, holes are not counted  when  locating  an
       offset.  The  data is taken out of those parts of the file specified by
       the current view.


FFOORRTTRRAANN 7777 NNOOTTEESS
       The MPI standard prescribes portable  Fortran  syntax  for  the  OFFSET
       argument only for Fortran 90. FORTRAN 77 users may use the non-portable
       syntax

            INTEGER*MPIOFFSETKIND OFFSET

       where MPIOFFSETKIND is a constant defined in  mpif.h  and  gives  the
       length of the declared integer in bytes.


NNOOTTEESS
       All  the  nonblocking  collective  routines for data access are "split"
       into two routines, each with begin or end as a  suffix.  These  split
       collective routines are subject to the semantic rules described in Sec-
       tion 9.4.5 of the MPI-2 standard.


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 2M0P0I6Filereadatallbegin(3OpenMPI)