osx man page for mpi_pack_external_size

MPI_Pack_external_size(3OpenMPI)										  MPI_Pack_external_size(3OpenMPI)

NAME
       MPI_Pack_external_size - Calculates upper bound on space needed to write to a portable format

SYNTAX
C Syntax
       #include <mpi.h>
       int MPI_Pack_external_size(char *datarep, int incount,
	    MPI_Datatype datatype, MPI_Aint *size)

Fortran Syntax
       INCLUDE 'mpif.h'
       MPI_PACK_EXTERNAL_SIZE(DATAREP, INCOUNT, DATATYPE, SIZE, IERROR)

	    INTEGER	   INCOUNT, DATATYPE, IERROR
	    INTEGER (KIND=MPI_ADDRESS_KIND) SIZE
	    CHARACTER*(*)  DATAREP

C++ Syntax
       #include <mpi.h>
       MPI::Aint MPI::Datatype::Pack_external_size(const char* datarep,
	    int incount) const

INPUT PARAMETERS
       datarep	 Data representation (string).

       incount	 Number of input data items (integer).

       datatype  Datatype of each input data item (handle).

OUTPUT PARAMETERS
       size	 Upper bound on size of packed message, in bytes (integer).

       IERROR	 Fortran only: Error status (integer).

DESCRIPTION
       MPI_Pack_external_size  allows the application to find out how much space is needed to pack a message in the portable format defined by the
       MPI Forum. It returns in size an upper bound on the increment in position that would occur in a call to	MPI_Pack_external  with  the  same
       values for datarep, incount, and datatype.

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

NOTES
       The datarep argument specifies the data format. The only valid value in the current version of MPI is "external32". The	argument  is  pro-
       vided for future extensibility.

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::ERRORS_THROW_EXCEPTIONS, 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 MPI_Comm_set_errhandler; the predefined error handler MPI_ERRORS_RETURN  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 the MPI man page for a full list of MPI error codes.

SEE ALSO
       MPI_Pack_external
       MPI_Unpack_external

Open MPI 1.2							  September 2006				  MPI_Pack_external_size(3OpenMPI)