if (ignore_env == 0 && (ss = get_env_value ("COLUMNS")))
if (ignore_env == 0 && (ss = get_env_value ("COLUMNS")) && *ss != '\0')
_rl_get_screen_size (tty, ignore_env)     int tty, ignore_env;{  char *ss;#if defined (TIOCGWINSZ)  struct winsize window_size;#endif /* TIOCGWINSZ */#if defined (TIOCGWINSZ)  if (ioctl (tty, TIOCGWINSZ, &window_size) == 0)    {      screenwidth = (int) window_size.ws_col;      screenheight = (int) window_size.ws_row;    }#endif /* TIOCGWINSZ */#if defined (__EMX__)  _emx_get_screensize (&screenwidth, &screenheight);#endif  /* Environment variable COLUMNS overrides setting of "co" if IGNORE_ENV     is unset. */  if (screenwidth <= 0)    {      if (ignore_env == 0 && (ss = get_env_value ("COLUMNS")))	screenwidth = atoi (ss);#if !defined (__DJGPP__)      if (screenwidth <= 0 && term_string_buffer)	screenwidth = tgetnum ("co");#endif    }  /* Environment variable LINES overrides setting of "li" if IGNORE_ENV     is unset. */  if (screenheight <= 0)    {      if (ignore_env == 0 && (ss = get_env_value ("LINES")))	screenheight = atoi (ss);#if !defined (__DJGPP__)      if (screenheight <= 0 && term_string_buffer)	screenheight = tgetnum ("li");#endif    }  /* If all else fails, default to 80x24 terminal. */  if (screenwidth <= 1)    screenwidth = 80;  if (screenheight <= 0)    screenheight = 24;  /* If we're being compiled as part of bash, set the environment     variables $LINES and $COLUMNS to new values.  Otherwise, just     do a pair of putenv () or setenv () calls. */  set_lines_and_columns (screenheight, screenwidth);  if (_rl_term_autowrap == 0)    screenwidth--;  screenchars = screenwidth * screenheight;}