-/* Define _POSIX_VDISABLE if we are not using the `new' tty driver and
- it is not already defined. It is used both to determine if a
- special character is disabled and to disable certain special
- characters. Posix systems should set to 0, USG systems to -1. */
-#if !defined (NEW_TTY_DRIVER) && !defined (_POSIX_VDISABLE)
-# if defined (_POSIX_VERSION)
-# define _POSIX_VDISABLE 0
-# else /* !_POSIX_VERSION */
-# define _POSIX_VDISABLE -1
-# endif /* !_POSIX_VERSION */
-#endif /* !NEW_TTY_DRIVER && !_POSIX_VDISABLE */
-
-#if 1
-# define D_NAMLEN(d) strlen ((d)->d_name)
-#else /* !1 */
-
-#if !defined (SHELL) && (defined (_POSIX_VERSION) || defined (USGr3))
-# if !defined (HAVE_DIRENT_H)
-# define HAVE_DIRENT_H
-# endif /* !HAVE_DIRENT_H */
-#endif /* !SHELL && (_POSIX_VERSION || USGr3) */
-
-#if defined (HAVE_DIRENT_H)
-# include <dirent.h>
-# if !defined (direct)
-# define direct dirent
-# endif /* !direct */
-# define D_NAMLEN(d) strlen ((d)->d_name)
-#else /* !HAVE_DIRENT_H */
-# define D_NAMLEN(d) ((d)->d_namlen)
-# if defined (USG)
-# if defined (Xenix)
-# include <sys/ndir.h>
-# else /* !Xenix (but USG...) */
-# include "ndir.h"
-# endif /* !Xenix */
-# else /* !USG */
-# include <sys/dir.h>
-# endif /* !USG */
-#endif /* !HAVE_DIRENT_H */
-#endif /* !1 */
-
-#if defined (USG) && defined (TIOCGWINSZ) && !defined (Linux)
-# include <sys/stream.h>
-# if defined (HAVE_SYS_PTEM_H)
-# include <sys/ptem.h>
-# endif /* HAVE_SYS_PTEM_H */
-# if defined (HAVE_SYS_PTE_H)
-# include <sys/pte.h>
-# endif /* HAVE_SYS_PTE_H */
-#endif /* USG && TIOCGWINSZ && !Linux */
-