MPIPacksize(3OpenMPI) MPIPacksize(3OpenMPI)

NAME
       MMPPIIPPaacckkssiizzee  -  Returns the upper bound on the amount of space needed
       to pack a message.


SSYYNNTTAAXX
CC SSyynnttaaxx
       #include 
       int MPIPacksize(int incount, MPIDatatype datatype, MPIComm comm,
            int *size)


FFoorrttrraann SSyynnttaaxx
       INCLUDE 'mpif.h'
       MPIPACKSIZE(INCOUNT, DATATYPE, COMM, SIZE, IERROR)
            INTEGER   INCOUNT, DATATYPE, COMM, SIZE, IERROR


CC++++ SSyynnttaaxx
       #include 
       int Datatype::Packsize(int incount, const Comm& comm) const


IINNPPUUTT PPAARRAAMMEETTEERRSS
       incount   Count argument to packing call (integer).

       datatype  Datatype argument to packing call (handle).

       comm      Communicator argument to packing call (handle).


OOUUTTPPUUTT PPAARRAAMMEETTEERRSS
       size      Upper bound on size of packed message, in bytes (integer).

       IERROR    Fortran only: Error status (integer).


DESCRIPTION
       MPIPacksize allows the application to find  out  how  much  space  is
       needed  to  pack  a message. A call to MPIPacksize(incount, datatype,
       comm, size) returns in size an upper bound on the increment in position
       that  would  occur  in  a  call  to  MPIPack, with the same values for
       incount, datatype, and comm.

       RRaattiioonnaallee::  The call returns an  upper  bound,  rather  than  an  exact
       bound,  since  the exact amount of space needed to pack the message may
       depend on the context (e.g., first message packed in a packing unit may
       take more space).


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. By default, this error handler aborts the MPI job,  except  for
       I/O   function   errors.   The   error  handler  may  be  changed  with
       MPICommseterrhandler; the predefined error handler MPIERRORSRETURN
       may  be  used  to cause error values to be returned. Note that MPI does
       not guarantee that an MPI program can continue past an error.


SEE ALSO
       MPIPack
       MPIUnpack





Open MPI 1.2                    September 2006         MPIPacksize(3OpenMPI)