Function mpi::ffi::PMPI_File_read_at_all_begin

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