Function mpi::ffi::MPI_File_read_at

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