Function mpi::ffi::MPI_File_read_at_all_begin

pub unsafe extern fn MPI_File_read_at_all_begin(fh: MPI_File,
                                                offset: MPI_Offset,
                                                buf: *mut c_void,
                                                count: c_int,
                                                datatype: MPI_Datatype)
                                                -> c_int