Remove OTTYDISC, NETLDISC and NTTYDISC definitions.

When I ported most applications away from <sgtty.h>, I noticed none of
them were actually using these definitions. I kept them in place,
because I didn't want to touch tools like pstat(8) and stty(1).

In preparation for the MPSAFE TTY layer, remove these definitions. This
doesn't have any impact with respect to binary compatibility (see
tty_conf.c).

We couldn now add an #error to <sys/ioctl_compat.h> when included
outside the kernel. Unfortunately, kdump's mkioctls includes this file
unconditionally.

Approved by:	philip (mentor)

bin/stty/print.c

@@ -44,8 +44,6 @@ __FBSDID("$FreeBSD$");
 #include "stty.h"
 #include "extern.h"
 
-#include <sys/ioctl_compat.h>	/* XXX NTTYDISC is too well hidden */
-
 static void  binit(const char *);
 static void  bput(const char *);
 static const char *ccval(struct cchar *, int);
@@ -64,9 +62,6 @@ print(struct termios *tp, struct winsize *wp, int ldisc, enum FMT fmt)
 	/* Line discipline. */
 	if (ldisc != TTYDISC) {
 		switch(ldisc) {
-		case NTTYDISC:
-			cnt += printf("new tty disc; ");
-			break;
 		case SLIPDISC:
 			cnt += printf("slip disc; ");
 			break;

sys/sys/ioctl_compat.h

@@ -61,8 +61,6 @@ struct ltchars {
 /*
  * Structure for TIOCGETP and TIOCSETP ioctls.
  */
-#ifndef _SGTTYB_
-#define	_SGTTYB_
 struct sgttyb {
 	char	sg_ispeed;		/* input speed */
 	char	sg_ospeed;		/* output speed */
@@ -70,7 +68,6 @@ struct sgttyb {
 	char	sg_kill;		/* kill character */
 	short	sg_flags;		/* mode flags */
 };
-#endif
 
 #define	OTIOCGETD	_IOR('t', 0, int)	/* get line discipline */
 #define	OTIOCSETD	_IOW('t', 1, int)	/* set line discipline */
@@ -152,9 +149,4 @@ struct sgttyb {
 
 #endif /* _KERNEL */
 
-/* XXX publish these so stty(1) can still report them */
-#define	OTTYDISC	0
-#define	NETLDISC	1
-#define	NTTYDISC	2
-
 #endif /* !_SYS_IOCTL_COMPAT_H_ */

usr.sbin/pstat/pstat.c

@@ -54,7 +54,6 @@ __FBSDID("$FreeBSD$");
 #include <sys/stat.h>
 #include <sys/stdint.h>
 #include <sys/ioctl.h>
-#include <sys/ioctl_compat.h>	/* XXX NTTYDISC is too well hidden */
 #include <sys/tty.h>
 #include <sys/blist.h>
 
@@ -367,9 +366,6 @@ ttyprt(struct xtty *xt)
 	case TTYDISC:
 		(void)printf("term\n");
 		break;
-	case NTTYDISC:
-		(void)printf("ntty\n");
-		break;
 	case SLIPDISC:
 		(void)printf("slip\n");
 		break;