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tty.c revision 1.22
      1  1.22      jdc /*	$NetBSD: tty.c,v 1.22 2000/06/15 21:20:16 jdc Exp $	*/
      2   1.7    mikel 
      3   1.1  mycroft /*-
      4   1.6      cgd  * Copyright (c) 1992, 1993, 1994
      5   1.2      cgd  *	The Regents of the University of California.  All rights reserved.
      6   1.1  mycroft  *
      7   1.1  mycroft  * Redistribution and use in source and binary forms, with or without
      8   1.1  mycroft  * modification, are permitted provided that the following conditions
      9   1.1  mycroft  * are met:
     10   1.1  mycroft  * 1. Redistributions of source code must retain the above copyright
     11   1.1  mycroft  *    notice, this list of conditions and the following disclaimer.
     12   1.1  mycroft  * 2. Redistributions in binary form must reproduce the above copyright
     13   1.1  mycroft  *    notice, this list of conditions and the following disclaimer in the
     14   1.1  mycroft  *    documentation and/or other materials provided with the distribution.
     15   1.1  mycroft  * 3. All advertising materials mentioning features or use of this software
     16   1.1  mycroft  *    must display the following acknowledgement:
     17   1.1  mycroft  *	This product includes software developed by the University of
     18   1.1  mycroft  *	California, Berkeley and its contributors.
     19   1.1  mycroft  * 4. Neither the name of the University nor the names of its contributors
     20   1.1  mycroft  *    may be used to endorse or promote products derived from this software
     21   1.1  mycroft  *    without specific prior written permission.
     22   1.1  mycroft  *
     23   1.1  mycroft  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24   1.1  mycroft  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25   1.1  mycroft  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26   1.1  mycroft  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27   1.1  mycroft  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28   1.1  mycroft  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29   1.1  mycroft  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30   1.1  mycroft  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31   1.1  mycroft  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32   1.1  mycroft  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33   1.1  mycroft  * SUCH DAMAGE.
     34   1.1  mycroft  */
     35   1.1  mycroft 
     36   1.7    mikel #include <sys/cdefs.h>
     37   1.1  mycroft #ifndef lint
     38   1.7    mikel #if 0
     39  1.10    perry static char sccsid[] = "@(#)tty.c	8.6 (Berkeley) 1/10/95";
     40   1.7    mikel #else
     41  1.22      jdc __RCSID("$NetBSD: tty.c,v 1.22 2000/06/15 21:20:16 jdc Exp $");
     42   1.7    mikel #endif
     43  1.11      mrg #endif				/* not lint */
     44  1.11      mrg 
     45  1.11      mrg #include <sys/types.h>
     46   1.1  mycroft 
     47   1.6      cgd #include <stdlib.h>
     48   1.1  mycroft #include <termios.h>
     49   1.1  mycroft #include <unistd.h>
     50  1.16    blymn #include <sys/fcntl.h>
     51  1.16    blymn #include <sys/ioctl.h>
     52   1.1  mycroft 
     53   1.6      cgd #include "curses.h"
     54  1.14      jdc #include "curses_private.h"
     55   1.6      cgd 
     56   1.2      cgd /*
     57   1.2      cgd  * In general, curses should leave tty hardware settings alone (speed, parity,
     58   1.2      cgd  * word size).  This is most easily done in BSD by using TCSASOFT on all
     59   1.2      cgd  * tcsetattr calls.  On other systems, it would be better to get and restore
     60   1.2      cgd  * those attributes at each change, or at least when stopped and restarted.
     61   1.2      cgd  * See also the comments in getterm().
     62   1.2      cgd  */
     63   1.2      cgd #ifdef TCSASOFT
     64  1.11      mrg int	__tcaction = 1;			/* Ignore hardware settings. */
     65   1.2      cgd #else
     66  1.11      mrg int	__tcaction = 0;
     67   1.2      cgd #endif
     68   1.2      cgd 
     69  1.22      jdc struct termios	__orig_termios, __baset;
     70  1.22      jdc int		__endwin;
     71  1.22      jdc static struct	termios cbreakt, rawt, *curt;
     72  1.22      jdc static int	useraw;
     73  1.22      jdc static int	ovmin = 1;
     74  1.22      jdc static int	ovtime = 0;
     75   1.1  mycroft 
     76   1.2      cgd #ifndef	OXTABS
     77   1.2      cgd #ifdef	XTABS			/* SMI uses XTABS. */
     78   1.2      cgd #define	OXTABS	XTABS
     79   1.2      cgd #else
     80   1.2      cgd #define	OXTABS	0
     81   1.2      cgd #endif
     82   1.2      cgd #endif
     83   1.2      cgd 
     84   1.1  mycroft /*
     85   1.1  mycroft  * gettmode --
     86   1.1  mycroft  *	Do terminal type initialization.
     87   1.1  mycroft  */
     88   1.1  mycroft int
     89  1.15    blymn gettmode(void)
     90   1.1  mycroft {
     91   1.2      cgd 	useraw = 0;
     92  1.11      mrg 
     93   1.2      cgd 	if (tcgetattr(STDIN_FILENO, &__orig_termios))
     94   1.2      cgd 		return (ERR);
     95   1.2      cgd 
     96   1.2      cgd 	__baset = __orig_termios;
     97   1.2      cgd 	__baset.c_oflag &= ~OXTABS;
     98  1.19    blymn 
     99  1.11      mrg 	GT = 0;			/* historical. was used before we wired OXTABS
    100  1.11      mrg 				 * off */
    101   1.2      cgd 	NONL = (__baset.c_oflag & ONLCR) == 0;
    102   1.1  mycroft 
    103   1.2      cgd 	/*
    104   1.2      cgd 	 * XXX
    105   1.2      cgd 	 * System V and SMI systems overload VMIN and VTIME, such that
    106   1.2      cgd 	 * VMIN is the same as the VEOF element, and VTIME is the same
    107   1.2      cgd 	 * as the VEOL element.  This means that, if VEOF was ^D, the
    108   1.2      cgd 	 * default VMIN is 4.  Majorly stupid.
    109   1.2      cgd 	 */
    110   1.2      cgd 	cbreakt = __baset;
    111  1.18  mycroft 	cbreakt.c_lflag &= ~(ECHO | ECHONL | ICANON);
    112   1.2      cgd 	cbreakt.c_cc[VMIN] = 1;
    113   1.2      cgd 	cbreakt.c_cc[VTIME] = 0;
    114   1.2      cgd 
    115   1.2      cgd 	rawt = cbreakt;
    116  1.11      mrg 	rawt.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | INLCR | IGNCR | ICRNL | IXON);
    117   1.2      cgd 	rawt.c_oflag &= ~OPOST;
    118  1.18  mycroft 	rawt.c_lflag &= ~(ISIG | IEXTEN);
    119   1.2      cgd 
    120   1.2      cgd 	/*
    121   1.2      cgd 	 * In general, curses should leave hardware-related settings alone.
    122   1.2      cgd 	 * This includes parity and word size.  Older versions set the tty
    123   1.2      cgd 	 * to 8 bits, no parity in raw(), but this is considered to be an
    124   1.2      cgd 	 * artifact of the old tty interface.  If it's desired to change
    125   1.2      cgd 	 * parity and word size, the TCSASOFT bit has to be removed from the
    126   1.2      cgd 	 * calls that switch to/from "raw" mode.
    127   1.2      cgd 	 */
    128   1.2      cgd 	if (!__tcaction) {
    129   1.2      cgd 		rawt.c_iflag &= ~ISTRIP;
    130  1.11      mrg 		rawt.c_cflag &= ~(CSIZE | PARENB);
    131   1.2      cgd 		rawt.c_cflag |= CS8;
    132   1.2      cgd 	}
    133   1.1  mycroft 
    134   1.2      cgd 	curt = &__baset;
    135   1.2      cgd 	return (tcsetattr(STDIN_FILENO, __tcaction ?
    136   1.2      cgd 	    TCSASOFT | TCSADRAIN : TCSADRAIN, curt) ? ERR : OK);
    137   1.1  mycroft }
    138   1.1  mycroft 
    139   1.1  mycroft int
    140  1.15    blymn raw(void)
    141   1.1  mycroft {
    142   1.9     phil 	/* Check if we need to restart ... */
    143  1.22      jdc 	if (__endwin)
    144   1.9     phil 		__endwin = 0;
    145  1.11      mrg 
    146   1.1  mycroft 	useraw = __pfast = __rawmode = 1;
    147   1.2      cgd 	curt = &rawt;
    148   1.2      cgd 	return (tcsetattr(STDIN_FILENO, __tcaction ?
    149   1.6      cgd 	    TCSASOFT | TCSADRAIN : TCSADRAIN, curt) ? ERR : OK);
    150   1.1  mycroft }
    151   1.1  mycroft 
    152   1.1  mycroft int
    153  1.15    blymn noraw(void)
    154   1.1  mycroft {
    155   1.9     phil 	/* Check if we need to restart ... */
    156  1.22      jdc 	if (__endwin)
    157   1.9     phil 		__endwin = 0;
    158  1.11      mrg 
    159   1.1  mycroft 	useraw = __pfast = __rawmode = 0;
    160   1.2      cgd 	curt = &__baset;
    161   1.2      cgd 	return (tcsetattr(STDIN_FILENO, __tcaction ?
    162   1.6      cgd 	    TCSASOFT | TCSADRAIN : TCSADRAIN, curt) ? ERR : OK);
    163   1.1  mycroft }
    164   1.1  mycroft 
    165   1.1  mycroft int
    166  1.15    blymn cbreak(void)
    167   1.1  mycroft {
    168   1.9     phil 	/* Check if we need to restart ... */
    169  1.22      jdc 	if (__endwin)
    170   1.9     phil 		__endwin = 0;
    171  1.11      mrg 
    172   1.1  mycroft 	__rawmode = 1;
    173   1.2      cgd 	curt = useraw ? &rawt : &cbreakt;
    174   1.2      cgd 	return (tcsetattr(STDIN_FILENO, __tcaction ?
    175   1.6      cgd 	    TCSASOFT | TCSADRAIN : TCSADRAIN, curt) ? ERR : OK);
    176   1.1  mycroft }
    177   1.1  mycroft 
    178   1.1  mycroft int
    179  1.15    blymn nocbreak(void)
    180   1.1  mycroft {
    181   1.9     phil 	/* Check if we need to restart ... */
    182  1.22      jdc 	if (__endwin)
    183   1.9     phil 		__endwin = 0;
    184   1.1  mycroft 
    185   1.1  mycroft 	__rawmode = 0;
    186   1.2      cgd 	curt = useraw ? &rawt : &__baset;
    187   1.2      cgd 	return (tcsetattr(STDIN_FILENO, __tcaction ?
    188   1.6      cgd 	    TCSASOFT | TCSADRAIN : TCSADRAIN, curt) ? ERR : OK);
    189   1.1  mycroft }
    190  1.11      mrg 
    191  1.11      mrg int
    192  1.15    blymn __delay(void)
    193  1.11      mrg  {
    194  1.11      mrg 	/* Check if we need to restart ... */
    195  1.22      jdc 	if (__endwin)
    196  1.11      mrg 		__endwin = 0;
    197  1.11      mrg 
    198  1.11      mrg 	rawt.c_cc[VMIN] = 1;
    199  1.11      mrg 	rawt.c_cc[VTIME] = 0;
    200  1.11      mrg 	cbreakt.c_cc[VMIN] = 1;
    201  1.11      mrg 	cbreakt.c_cc[VTIME] = 0;
    202  1.11      mrg 	__baset.c_cc[VMIN] = 1;
    203  1.11      mrg 	__baset.c_cc[VTIME] = 0;
    204  1.11      mrg 
    205  1.11      mrg 	return (tcsetattr(STDIN_FILENO, __tcaction ?
    206  1.11      mrg 		TCSASOFT : TCSANOW, curt) ? ERR : OK);
    207  1.11      mrg }
    208  1.11      mrg 
    209  1.11      mrg int
    210  1.15    blymn __nodelay(void)
    211  1.11      mrg {
    212  1.11      mrg 	/* Check if we need to restart ... */
    213  1.22      jdc 	if (__endwin)
    214  1.11      mrg 		__endwin = 0;
    215  1.11      mrg 
    216  1.11      mrg 	rawt.c_cc[VMIN] = 0;
    217  1.11      mrg 	rawt.c_cc[VTIME] = 0;
    218  1.11      mrg 	cbreakt.c_cc[VMIN] = 0;
    219  1.11      mrg 	cbreakt.c_cc[VTIME] = 0;
    220  1.11      mrg 	__baset.c_cc[VMIN] = 0;
    221  1.11      mrg 	__baset.c_cc[VTIME] = 0;
    222  1.11      mrg 
    223  1.11      mrg 	return (tcsetattr(STDIN_FILENO, __tcaction ?
    224  1.11      mrg 		TCSASOFT : TCSANOW, curt) ? ERR : OK);
    225  1.11      mrg }
    226  1.11      mrg 
    227  1.11      mrg void
    228  1.15    blymn __save_termios(void)
    229  1.11      mrg {
    230  1.11      mrg 	/* Check if we need to restart ... */
    231  1.22      jdc 	if (__endwin)
    232  1.11      mrg 		__endwin = 0;
    233  1.11      mrg 
    234  1.11      mrg 	ovmin = cbreakt.c_cc[VMIN];
    235  1.11      mrg 	ovtime = cbreakt.c_cc[VTIME];
    236  1.11      mrg }
    237  1.11      mrg 
    238  1.11      mrg void
    239  1.15    blymn __restore_termios(void)
    240  1.11      mrg {
    241  1.11      mrg 	/* Check if we need to restart ... */
    242  1.22      jdc 	if (__endwin)
    243  1.11      mrg 		__endwin = 0;
    244  1.11      mrg 
    245  1.11      mrg 	rawt.c_cc[VMIN] = ovmin;
    246  1.11      mrg 	rawt.c_cc[VTIME] = ovtime;
    247  1.11      mrg 	cbreakt.c_cc[VMIN] = ovmin;
    248  1.11      mrg 	cbreakt.c_cc[VTIME] = ovtime;
    249  1.11      mrg 	__baset.c_cc[VMIN] = ovmin;
    250  1.11      mrg 	__baset.c_cc[VTIME] = ovtime;
    251  1.11      mrg }
    252  1.11      mrg 
    253  1.11      mrg int
    254  1.15    blymn __timeout(int delay)
    255  1.11      mrg {
    256  1.11      mrg 	/* Check if we need to restart ... */
    257  1.22      jdc 	if (__endwin)
    258  1.11      mrg 		__endwin = 0;
    259  1.11      mrg 
    260  1.11      mrg 	ovmin = cbreakt.c_cc[VMIN];
    261  1.11      mrg 	ovtime = cbreakt.c_cc[VTIME];
    262  1.11      mrg 	rawt.c_cc[VMIN] = 0;
    263  1.11      mrg 	rawt.c_cc[VTIME] = delay;
    264  1.11      mrg 	cbreakt.c_cc[VMIN] = 0;
    265  1.11      mrg 	cbreakt.c_cc[VTIME] = delay;
    266  1.11      mrg 	__baset.c_cc[VMIN] = 0;
    267  1.11      mrg 	__baset.c_cc[VTIME] = delay;
    268  1.11      mrg 
    269  1.11      mrg 	return (tcsetattr(STDIN_FILENO, __tcaction ?
    270  1.11      mrg 		TCSASOFT | TCSANOW : TCSANOW, curt) ? ERR : OK);
    271  1.11      mrg }
    272  1.11      mrg 
    273  1.11      mrg int
    274  1.15    blymn __notimeout(void)
    275  1.11      mrg {
    276  1.11      mrg 	/* Check if we need to restart ... */
    277  1.22      jdc 	if (__endwin)
    278  1.11      mrg 		__endwin = 0;
    279  1.11      mrg 
    280  1.11      mrg 	rawt.c_cc[VMIN] = 1;
    281  1.11      mrg 	rawt.c_cc[VTIME] = 0;
    282  1.11      mrg 	cbreakt.c_cc[VMIN] = 1;
    283  1.11      mrg 	cbreakt.c_cc[VTIME] = 0;
    284  1.11      mrg 	__baset.c_cc[VMIN] = 1;
    285  1.11      mrg 	__baset.c_cc[VTIME] = 0;
    286  1.11      mrg 
    287  1.11      mrg 	return (tcsetattr(STDIN_FILENO, __tcaction ?
    288  1.11      mrg 		TCSASOFT | TCSANOW : TCSANOW, curt) ? ERR : OK);
    289  1.11      mrg }
    290  1.11      mrg 
    291   1.1  mycroft int
    292  1.15    blymn echo(void)
    293   1.1  mycroft {
    294   1.9     phil 	/* Check if we need to restart ... */
    295  1.22      jdc 	if (__endwin)
    296   1.9     phil 		__endwin = 0;
    297   1.9     phil 
    298   1.1  mycroft 	__echoit = 1;
    299  1.17  mycroft 	return (OK);
    300   1.1  mycroft }
    301   1.1  mycroft 
    302   1.1  mycroft int
    303  1.15    blymn noecho(void)
    304   1.1  mycroft {
    305   1.9     phil 	/* Check if we need to restart ... */
    306  1.22      jdc 	if (__endwin)
    307   1.9     phil 		__endwin = 0;
    308   1.9     phil 
    309   1.1  mycroft 	__echoit = 0;
    310  1.17  mycroft 	return (OK);
    311   1.1  mycroft }
    312   1.1  mycroft 
    313   1.1  mycroft int
    314  1.15    blymn nl(void)
    315   1.1  mycroft {
    316   1.9     phil 	/* Check if we need to restart ... */
    317  1.22      jdc 	if (__endwin)
    318   1.9     phil 		__endwin = 0;
    319   1.9     phil 
    320   1.1  mycroft 	rawt.c_iflag |= ICRNL;
    321   1.1  mycroft 	rawt.c_oflag |= ONLCR;
    322   1.2      cgd 	cbreakt.c_iflag |= ICRNL;
    323   1.2      cgd 	cbreakt.c_oflag |= ONLCR;
    324   1.2      cgd 	__baset.c_iflag |= ICRNL;
    325   1.2      cgd 	__baset.c_oflag |= ONLCR;
    326   1.1  mycroft 
    327   1.1  mycroft 	__pfast = __rawmode;
    328   1.2      cgd 	return (tcsetattr(STDIN_FILENO, __tcaction ?
    329   1.6      cgd 	    TCSASOFT | TCSADRAIN : TCSADRAIN, curt) ? ERR : OK);
    330   1.1  mycroft }
    331   1.1  mycroft 
    332   1.1  mycroft int
    333  1.15    blymn nonl(void)
    334   1.1  mycroft {
    335   1.9     phil 	/* Check if we need to restart ... */
    336  1.22      jdc 	if (__endwin)
    337   1.9     phil 		__endwin = 0;
    338   1.9     phil 
    339   1.1  mycroft 	rawt.c_iflag &= ~ICRNL;
    340   1.1  mycroft 	rawt.c_oflag &= ~ONLCR;
    341   1.2      cgd 	cbreakt.c_iflag &= ~ICRNL;
    342   1.2      cgd 	cbreakt.c_oflag &= ~ONLCR;
    343   1.2      cgd 	__baset.c_iflag &= ~ICRNL;
    344   1.2      cgd 	__baset.c_oflag &= ~ONLCR;
    345   1.1  mycroft 
    346   1.1  mycroft 	__pfast = 1;
    347   1.2      cgd 	return (tcsetattr(STDIN_FILENO, __tcaction ?
    348   1.6      cgd 	    TCSASOFT | TCSADRAIN : TCSADRAIN, curt) ? ERR : OK);
    349   1.2      cgd }
    350   1.2      cgd 
    351  1.14      jdc int
    352  1.15    blymn intrflush(WINDOW *win, bool bf)	/*ARGSUSED*/
    353  1.14      jdc {
    354  1.14      jdc 	/* Check if we need to restart ... */
    355  1.22      jdc 	if (__endwin)
    356  1.14      jdc 		__endwin = 0;
    357  1.14      jdc 
    358  1.14      jdc 	if (bf) {
    359  1.14      jdc 		rawt.c_lflag &= ~NOFLSH;
    360  1.14      jdc 		cbreakt.c_lflag &= ~NOFLSH;
    361  1.14      jdc 		__baset.c_lflag &= ~NOFLSH;
    362  1.14      jdc 	} else {
    363  1.14      jdc 		rawt.c_lflag |= NOFLSH;
    364  1.14      jdc 		cbreakt.c_lflag |= NOFLSH;
    365  1.14      jdc 		__baset.c_lflag |= NOFLSH;
    366  1.14      jdc 	}
    367  1.14      jdc 
    368  1.14      jdc 	__pfast = 1;
    369  1.14      jdc 	return (tcsetattr(STDIN_FILENO, __tcaction ?
    370  1.14      jdc 	    TCSASOFT | TCSADRAIN : TCSADRAIN, curt) ? ERR : OK);
    371  1.14      jdc }
    372  1.14      jdc 
    373   1.2      cgd void
    374  1.15    blymn __startwin(void)
    375   1.2      cgd {
    376   1.6      cgd 	static char *stdbuf;
    377   1.6      cgd 	static size_t len;
    378   1.6      cgd 
    379  1.11      mrg 	(void) fflush(stdout);
    380   1.6      cgd 
    381   1.6      cgd 	/*
    382   1.6      cgd 	 * Some C libraries default to a 1K buffer when talking to a tty.
    383   1.6      cgd 	 * With a larger screen, especially across a network, we'd like
    384   1.6      cgd 	 * to get it to all flush in a single write.  Make it twice as big
    385   1.6      cgd 	 * as just the characters (so that we have room for cursor motions
    386  1.11      mrg 	 * and attribute information) but no more than 8K.
    387   1.6      cgd 	 */
    388   1.6      cgd 	if (stdbuf == NULL) {
    389   1.6      cgd 		if ((len = LINES * COLS * 2) > 8192)
    390   1.6      cgd 			len = 8192;
    391   1.6      cgd 		if ((stdbuf = malloc(len)) == NULL)
    392   1.6      cgd 			len = 0;
    393   1.6      cgd 	}
    394  1.11      mrg 	(void) setvbuf(stdout, stdbuf, _IOFBF, len);
    395   1.2      cgd 
    396   1.2      cgd 	tputs(TI, 0, __cputchar);
    397   1.2      cgd 	tputs(VS, 0, __cputchar);
    398  1.20      jdc 	if (curscr->flags & __KEYPAD)
    399  1.20      jdc 		tputs(KS, 0, __cputchar);
    400  1.22      jdc 	__endwin = 0;
    401   1.1  mycroft }
    402   1.1  mycroft 
    403   1.1  mycroft int
    404  1.15    blymn endwin(void)
    405   1.1  mycroft {
    406   1.8     phil 	return __stopwin();
    407  1.11      mrg }
    408  1.11      mrg 
    409  1.13    blymn bool
    410  1.15    blymn isendwin(void)
    411  1.11      mrg {
    412  1.13    blymn 	return (__endwin ? TRUE : FALSE);
    413  1.11      mrg }
    414  1.11      mrg 
    415  1.11      mrg int
    416  1.15    blymn flushinp(void)
    417  1.11      mrg {
    418  1.13    blymn 	(void) fpurge(stdin);
    419  1.11      mrg 	return (OK);
    420  1.14      jdc }
    421  1.14      jdc 
    422   1.1  mycroft /*
    423   1.1  mycroft  * The following routines, savetty and resetty are completely useless and
    424   1.1  mycroft  * are left in only as stubs.  If people actually use them they will almost
    425   1.1  mycroft  * certainly screw up the state of the world.
    426   1.1  mycroft  */
    427   1.1  mycroft static struct termios savedtty;
    428   1.1  mycroft int
    429  1.15    blymn savetty(void)
    430   1.1  mycroft {
    431   1.6      cgd 	return (tcgetattr(STDIN_FILENO, &savedtty) ? ERR : OK);
    432   1.1  mycroft }
    433   1.1  mycroft 
    434   1.1  mycroft int
    435  1.15    blymn resetty(void)
    436   1.1  mycroft {
    437   1.2      cgd 	return (tcsetattr(STDIN_FILENO, __tcaction ?
    438   1.6      cgd 	    TCSASOFT | TCSADRAIN : TCSADRAIN, &savedtty) ? ERR : OK);
    439  1.19    blymn }
    440  1.19    blymn 
    441  1.19    blymn /*
    442  1.19    blymn  * erasechar --
    443  1.19    blymn  *     Return the character of the erase key.
    444  1.19    blymn  *
    445  1.19    blymn  */
    446  1.19    blymn char
    447  1.19    blymn erasechar(void)
    448  1.19    blymn {
    449  1.19    blymn 	return __baset.c_cc[VERASE];
    450  1.19    blymn }
    451  1.19    blymn 
    452  1.19    blymn /*
    453  1.19    blymn  * killchar --
    454  1.19    blymn  *     Return the character of the kill key.
    455  1.19    blymn  */
    456  1.19    blymn char
    457  1.19    blymn killchar(void)
    458  1.19    blymn {
    459  1.19    blymn 	return __baset.c_cc[VKILL];
    460   1.1  mycroft }
    461