st_backward_space_files
rval = st_backward_space_files(un, -files, 0);
rval = st_backward_space_files(un, 1, 1);
return (st_backward_space_files(un, files, 1));
ST_FUNC(ST_DEVINFO, st_backward_space_files);
rval = st_backward_space_files(un, count, 0);
static int st_backward_space_files(struct scsi_tape *un, int64_t count,