oracular (3) MPI_Comm_f2c.openmpi.3.gz

NAME

       MPI_Comm_f2c,  MPI_Comm_c2f,  MPI_File_f2c,  MPI_File_c2f,  MPI_Info_f2c,  MPI_Info_c2f, MPI_Message_f2c,
       MPI_Message_c2f, MPI_Op_f2c, MPI_Op_c2f, MPI_Request_f2c,  MPI_Request_c2f,  MPI_Type_f2c,  MPI_Type_c2f,
       MPI_Win_f2c, MPI_Win_c2f  - Translates a C handle into a Fortran handle, or vice versa.

SYNTAX

C Syntax

       #include <mpi.h>
       MPI_Comm MPI_Comm_f2c(MPI_Fint comm)
       MPI_Fint MPI_Comm_c2f(MPI_Comm comm)

       MPI_File MPI_File_f2c(MPI_Fint file)
       MPI_Fint MPI_File_c2f(MPI_File file)

       MPI_Group MPI_Group_f2c(MPI Fint group)
       MPI_Fint MPI_Group_c2f(MPI Group group)

       MPI_Info MPI_Info_f2c(MPI_Fint info)
       MPI_Fint MPI_Info_c2f(MPI_Info info)

       MPI_Message MPI_Message_f2c(MPI_Fint message)
       MPI_Fint MPI_Message_c2f(MPI_Message message)

       MPI_Op MPI_Op_f2c(MPI_Fint op)
       MPI_Fint MPI_Op_c2f(MPI_Op op)

       MPI_Request MPI_Request_f2c(MPI_Fint request)
       MPI_Fint MPI_Request_c2f(MPI_Request request)

       MPI_Datatype MPI_Type_f2c(MPI_Fint datatype)
       MPI_Fint MPI_Type_c2f(MPI_Datatype datatype)

       MPI_Win MPI_Win_f2c(MPI_Fint win)
       MPI_Fint MPI_Win_c2f(MPI_Win win)

DESCRIPTION

       Handles are passed between Fortran and C or C++ by using an explicit C wrapper to convert Fortran handles
       to C handles. There is no direct access to C or C++ handles in Fortran. Handles are passed between C  and
       C++ using overloaded C++ operators called from C++ code. There is no direct access to C++ objects from C.
       The type definition MPI_Fint is provided in C/C++ for an integer of  the  size  that  matches  a  Fortran
       INTEGER;  usually, MPI_Fint will be equivalent to int. The handle translation functions are provided in C
       to convert from a Fortran handle (which is an integer) to a C handle, and vice versa.

       For example, if comm is a valid Fortran handle to a communicator, then MPI_Comm_f2c  returns  a  valid  C
       handle  to  that  same communicator; if comm = MPI_COMM_NULL (Fortran value), then MPI_Comm_f2c returns a
       null C handle; if comm is an invalid Fortran handle, then MPI_Comm_f2c returns an invalid C handle.

NOTE

       This function does not return an error value. Consequently, the result of calling it before  MPI_Init  or
       after MPI_Finalize is undefined.