Home | History | Annotate | Line # | Download | only in libcurses
tty.c revision 1.46.12.1
      1 /*	$NetBSD: tty.c,v 1.46.12.1 2018/10/20 06:58:22 pgoyette Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1992, 1993, 1994
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. Neither the name of the University nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/cdefs.h>
     33 #ifndef lint
     34 #if 0
     35 static char sccsid[] = "@(#)tty.c	8.6 (Berkeley) 1/10/95";
     36 #else
     37 __RCSID("$NetBSD: tty.c,v 1.46.12.1 2018/10/20 06:58:22 pgoyette Exp $");
     38 #endif
     39 #endif				/* not lint */
     40 
     41 #include <sys/fcntl.h>
     42 #include <sys/ioctl.h>
     43 #include <sys/param.h>
     44 #include <sys/types.h>
     45 
     46 #include <stdlib.h>
     47 #include <termios.h>
     48 #include <unistd.h>
     49 
     50 #include "curses.h"
     51 #include "curses_private.h"
     52 
     53 /*
     54  * In general, curses should leave tty hardware settings alone (speed, parity,
     55  * word size).  This is most easily done in BSD by using TCSASOFT on all
     56  * tcsetattr calls.  On other systems, it would be better to get and restore
     57  * those attributes at each change, or at least when stopped and restarted.
     58  * See also the comments in getterm().
     59  */
     60 #ifndef TCSASOFT
     61 #define	TCSASOFT	0
     62 #endif
     63 
     64 int __tcaction = TCSASOFT != 0;		/* Ignore hardware settings */
     65 
     66 #ifndef	OXTABS
     67 #ifdef	XTABS			/* SMI uses XTABS. */
     68 #define	OXTABS	XTABS
     69 #else
     70 #define	OXTABS	0
     71 #endif
     72 #endif
     73 
     74 /*
     75  * baudrate --
     76  *	Return the current baudrate
     77  */
     78 int
     79 baudrate(void)
     80 {
     81 
     82 	if (_cursesi_screen->notty == TRUE)
     83 		return 0;
     84 
     85 	return cfgetospeed(&_cursesi_screen->baset);
     86 }
     87 
     88 /*
     89  * gettmode --
     90  *	Do terminal type initialization.
     91  */
     92 int
     93 gettmode(void)
     94 {
     95 
     96 	if (_cursesi_gettmode(_cursesi_screen) == ERR)
     97 		return ERR;
     98 
     99 	__GT = _cursesi_screen->GT;
    100 	__NONL = _cursesi_screen->NONL;
    101 	return OK;
    102 }
    103 
    104 /*
    105  * _cursesi_gettmode --
    106  *      Do the terminal type initialisation for the tty attached to the
    107  *  given screen.
    108  */
    109 int
    110 _cursesi_gettmode(SCREEN *screen)
    111 {
    112 	screen->useraw = 0;
    113 
    114 	if (tcgetattr(fileno(screen->infd), &screen->orig_termios)) {
    115 		/* if the input fd is not a tty try the output */
    116 		if (tcgetattr(fileno(screen->infd), &screen->orig_termios)) {
    117 			/* not a tty ... we will disable tty related stuff */
    118 			screen->notty = TRUE;
    119 			__GT = 0;
    120 			__NONL = 0;
    121 			return OK;
    122 		}
    123 	}
    124 
    125 	screen->baset = screen->orig_termios;
    126 	screen->baset.c_oflag &= ~OXTABS;
    127 
    128 	screen->GT = 0;	/* historical. was used before we wired OXTABS off */
    129 	screen->NONL = (screen->baset.c_oflag & ONLCR) == 0;
    130 
    131 	/*
    132 	 * XXX
    133 	 * System V and SMI systems overload VMIN and VTIME, such that
    134 	 * VMIN is the same as the VEOF element, and VTIME is the same
    135 	 * as the VEOL element.  This means that, if VEOF was ^D, the
    136 	 * default VMIN is 4.  Majorly stupid.
    137 	 */
    138 	screen->cbreakt = screen->baset;
    139 	screen->cbreakt.c_lflag &= ~(ECHO | ECHONL | ICANON);
    140 	screen->cbreakt.c_cc[VMIN] = 1;
    141 	screen->cbreakt.c_cc[VTIME] = 0;
    142 
    143 	screen->rawt = screen->cbreakt;
    144 	screen->rawt.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | INLCR | IGNCR |
    145 				  ICRNL | IXON);
    146 	screen->rawt.c_oflag &= ~OPOST;
    147 	screen->rawt.c_lflag &= ~(ISIG | IEXTEN);
    148 
    149 #if TCSASOFT == 0
    150 	/*
    151 	 * In general, curses should leave hardware-related settings alone.
    152 	 * This includes parity and word size.  Older versions set the tty
    153 	 * to 8 bits, no parity in raw(), but this is considered to be an
    154 	 * artifact of the old tty interface.  If it's desired to change
    155 	 * parity and word size, the TCSASOFT bit has to be removed from the
    156 	 * calls that switch to/from "raw" mode.
    157 	 */
    158 	screen->rawt.c_iflag &= ~ISTRIP;
    159 	screen->rawt.c_cflag &= ~(CSIZE | PARENB);
    160 	screen->rawt.c_cflag |= CS8;
    161 #endif
    162 
    163 	screen->curt = &screen->baset;
    164 	return tcsetattr(fileno(screen->infd), TCSASOFT | TCSADRAIN,
    165 	    screen->curt) ? ERR : OK;
    166 }
    167 
    168 /*
    169  * raw --
    170  *	Put the terminal into raw mode
    171  */
    172 int
    173 raw(void)
    174 {
    175 #ifdef DEBUG
    176 	__CTRACE(__CTRACE_MISC, "raw()\n");
    177 #endif
    178 	/* Check if we need to restart ... */
    179 	if (_cursesi_screen->endwin)
    180 		__restartwin();
    181 
    182 	_cursesi_screen->useraw = __pfast = __rawmode = 1;
    183 	_cursesi_screen->curt = &_cursesi_screen->rawt;
    184 	if (_cursesi_screen->notty == TRUE)
    185 		return OK;
    186 	return tcsetattr(fileno(_cursesi_screen->infd), TCSASOFT | TCSADRAIN,
    187 	    _cursesi_screen->curt) ? ERR : OK;
    188 }
    189 
    190 /*
    191  * noraw --
    192  *	Put the terminal into cooked mode
    193  */
    194 int
    195 noraw(void)
    196 {
    197 #ifdef DEBUG
    198 	__CTRACE(__CTRACE_MISC, "noraw()\n");
    199 #endif
    200 	/* Check if we need to restart ... */
    201 	if (_cursesi_screen->endwin)
    202 		__restartwin();
    203 
    204 	_cursesi_screen->useraw = __pfast = __rawmode = 0;
    205 	if (_cursesi_screen->notty == TRUE)
    206 		return OK;
    207 	_cursesi_screen->curt = &_cursesi_screen->baset;
    208 	return tcsetattr(fileno(_cursesi_screen->infd), TCSASOFT | TCSADRAIN,
    209 	    _cursesi_screen->curt) ? ERR : OK;
    210 }
    211 
    212 /*
    213  * cbreak --
    214  * 	Enable cbreak mode
    215  */
    216 int
    217 cbreak(void)
    218 {
    219 #ifdef DEBUG
    220 	__CTRACE(__CTRACE_MISC, "cbreak()\n");
    221 #endif
    222 	/* Check if we need to restart ... */
    223 	if (_cursesi_screen->endwin)
    224 		__restartwin();
    225 
    226 	__rawmode = 1;
    227 	if (_cursesi_screen->notty == TRUE)
    228 		return OK;
    229 	_cursesi_screen->curt = _cursesi_screen->useraw ?
    230 		&_cursesi_screen->rawt : &_cursesi_screen->cbreakt;
    231 	return tcsetattr(fileno(_cursesi_screen->infd), TCSASOFT | TCSADRAIN,
    232 	    _cursesi_screen->curt) ? ERR : OK;
    233 }
    234 
    235 /*
    236  * nocbreak --
    237  *	Disable cbreak mode
    238  */
    239 int
    240 nocbreak(void)
    241 {
    242 #ifdef DEBUG
    243 	__CTRACE(__CTRACE_MISC, "nocbreak()\n");
    244 #endif
    245 	/* Check if we need to restart ... */
    246 	if (_cursesi_screen->endwin)
    247 		__restartwin();
    248 
    249 	__rawmode = 0;
    250 	if (_cursesi_screen->notty == TRUE)
    251 		return OK;
    252 	  /* if we were in halfdelay mode then nuke the timeout */
    253 	if ((_cursesi_screen->half_delay == TRUE) &&
    254 	    (__notimeout() == ERR))
    255 		return ERR;
    256 
    257 	_cursesi_screen->half_delay = FALSE;
    258 	_cursesi_screen->curt = _cursesi_screen->useraw ?
    259 		&_cursesi_screen->rawt : &_cursesi_screen->baset;
    260 	return tcsetattr(fileno(_cursesi_screen->infd), TCSASOFT | TCSADRAIN,
    261 	    _cursesi_screen->curt) ? ERR : OK;
    262 }
    263 
    264 /*
    265  * halfdelay --
    266  *    Put the terminal into cbreak mode with the specified timeout.
    267  *
    268  */
    269 int
    270 halfdelay(int duration)
    271 {
    272 	if ((duration < 1) || (duration > 255))
    273 		return ERR;
    274 
    275 	if (cbreak() == ERR)
    276 		return ERR;
    277 
    278 	if (__timeout(duration) == ERR)
    279 		return ERR;
    280 
    281 	_cursesi_screen->half_delay = TRUE;
    282 	return OK;
    283 }
    284 
    285 int
    286 __delay(void)
    287  {
    288 #ifdef DEBUG
    289 	__CTRACE(__CTRACE_MISC, "__delay()\n");
    290 #endif
    291 	/* Check if we need to restart ... */
    292 	if (_cursesi_screen->endwin)
    293 		__restartwin();
    294 
    295 	if (_cursesi_screen->notty == TRUE)
    296 		return OK;
    297 	_cursesi_screen->rawt.c_cc[VMIN] = 1;
    298 	_cursesi_screen->rawt.c_cc[VTIME] = 0;
    299 	_cursesi_screen->cbreakt.c_cc[VMIN] = 1;
    300 	_cursesi_screen->cbreakt.c_cc[VTIME] = 0;
    301 	_cursesi_screen->baset.c_cc[VMIN] = 1;
    302 	_cursesi_screen->baset.c_cc[VTIME] = 0;
    303 
    304 	if (tcsetattr(fileno(_cursesi_screen->infd), TCSASOFT | TCSANOW,
    305 	    _cursesi_screen->curt)) {
    306 		__restore_termios();
    307 		return ERR;
    308 	}
    309 
    310 	return OK;
    311 }
    312 
    313 int
    314 __nodelay(void)
    315 {
    316 #ifdef DEBUG
    317 	__CTRACE(__CTRACE_MISC, "__nodelay()\n");
    318 #endif
    319 	/* Check if we need to restart ... */
    320 	if (_cursesi_screen->endwin)
    321 		__restartwin();
    322 
    323 	if (_cursesi_screen->notty == TRUE)
    324 		return OK;
    325 	_cursesi_screen->rawt.c_cc[VMIN] = 0;
    326 	_cursesi_screen->rawt.c_cc[VTIME] = 0;
    327 	_cursesi_screen->cbreakt.c_cc[VMIN] = 0;
    328 	_cursesi_screen->cbreakt.c_cc[VTIME] = 0;
    329 	_cursesi_screen->baset.c_cc[VMIN] = 0;
    330 	_cursesi_screen->baset.c_cc[VTIME] = 0;
    331 
    332 	if (tcsetattr(fileno(_cursesi_screen->infd), TCSASOFT | TCSANOW,
    333 	    _cursesi_screen->curt)) {
    334 		__restore_termios();
    335 		return ERR;
    336 	}
    337 
    338 	return OK;
    339 }
    340 
    341 void
    342 __save_termios(void)
    343 {
    344 	/* Check if we need to restart ... */
    345 	if (_cursesi_screen->endwin)
    346 		__restartwin();
    347 
    348 	if (_cursesi_screen->notty == TRUE)
    349 		return;
    350 	_cursesi_screen->ovmin = _cursesi_screen->cbreakt.c_cc[VMIN];
    351 	_cursesi_screen->ovtime = _cursesi_screen->cbreakt.c_cc[VTIME];
    352 }
    353 
    354 void
    355 __restore_termios(void)
    356 {
    357 	/* Check if we need to restart ... */
    358 	if (_cursesi_screen->endwin)
    359 		__restartwin();
    360 
    361 	if (_cursesi_screen->notty == TRUE)
    362 		return;
    363 	_cursesi_screen->rawt.c_cc[VMIN] = _cursesi_screen->ovmin;
    364 	_cursesi_screen->rawt.c_cc[VTIME] = _cursesi_screen->ovtime;
    365 	_cursesi_screen->cbreakt.c_cc[VMIN] = _cursesi_screen->ovmin;
    366 	_cursesi_screen->cbreakt.c_cc[VTIME] = _cursesi_screen->ovtime;
    367 	_cursesi_screen->baset.c_cc[VMIN] = _cursesi_screen->ovmin;
    368 	_cursesi_screen->baset.c_cc[VTIME] = _cursesi_screen->ovtime;
    369 }
    370 
    371 int
    372 __timeout(int delay)
    373 {
    374 #ifdef DEBUG
    375 	__CTRACE(__CTRACE_MISC, "__timeout()\n");
    376 #endif
    377 	/* Check if we need to restart ... */
    378 	if (_cursesi_screen->endwin)
    379 		__restartwin();
    380 
    381 	if (_cursesi_screen->notty == TRUE)
    382 		return OK;
    383 	_cursesi_screen->ovmin = _cursesi_screen->cbreakt.c_cc[VMIN];
    384 	_cursesi_screen->ovtime = _cursesi_screen->cbreakt.c_cc[VTIME];
    385 	_cursesi_screen->rawt.c_cc[VMIN] = 0;
    386 	_cursesi_screen->rawt.c_cc[VTIME] = delay;
    387 	_cursesi_screen->cbreakt.c_cc[VMIN] = 0;
    388 	_cursesi_screen->cbreakt.c_cc[VTIME] = delay;
    389 	_cursesi_screen->baset.c_cc[VMIN] = 0;
    390 	_cursesi_screen->baset.c_cc[VTIME] = delay;
    391 
    392 	if (tcsetattr(fileno(_cursesi_screen->infd), TCSASOFT | TCSANOW,
    393 	    _cursesi_screen->curt)) {
    394 		__restore_termios();
    395 		return ERR;
    396 	}
    397 
    398 	return OK;
    399 }
    400 
    401 int
    402 __notimeout(void)
    403 {
    404 #ifdef DEBUG
    405 	__CTRACE(__CTRACE_MISC, "__notimeout()\n");
    406 #endif
    407 	/* Check if we need to restart ... */
    408 	if (_cursesi_screen->endwin)
    409 		__restartwin();
    410 
    411 	if (_cursesi_screen->notty == TRUE)
    412 		return OK;
    413 	_cursesi_screen->rawt.c_cc[VMIN] = 1;
    414 	_cursesi_screen->rawt.c_cc[VTIME] = 0;
    415 	_cursesi_screen->cbreakt.c_cc[VMIN] = 1;
    416 	_cursesi_screen->cbreakt.c_cc[VTIME] = 0;
    417 	_cursesi_screen->baset.c_cc[VMIN] = 1;
    418 	_cursesi_screen->baset.c_cc[VTIME] = 0;
    419 
    420 	return tcsetattr(fileno(_cursesi_screen->infd), TCSASOFT | TCSANOW,
    421 	    _cursesi_screen->curt) ? ERR : OK;
    422 }
    423 
    424 int
    425 echo(void)
    426 {
    427 #ifdef DEBUG
    428 	__CTRACE(__CTRACE_MISC, "echo()\n");
    429 #endif
    430 	/* Check if we need to restart ... */
    431 	if (_cursesi_screen->endwin)
    432 		__restartwin();
    433 
    434 	__echoit = 1;
    435 	return OK;
    436 }
    437 
    438 int
    439 noecho(void)
    440 {
    441 #ifdef DEBUG
    442 	__CTRACE(__CTRACE_MISC, "noecho()\n");
    443 #endif
    444 	/* Check if we need to restart ... */
    445 	if (_cursesi_screen->endwin)
    446 		__restartwin();
    447 
    448 	__echoit = 0;
    449 	return OK;
    450 }
    451 
    452 int
    453 nl(void)
    454 {
    455 #ifdef DEBUG
    456 	__CTRACE(__CTRACE_MISC, "nl()\n");
    457 #endif
    458 	/* Check if we need to restart ... */
    459 	if (_cursesi_screen->endwin)
    460 		__restartwin();
    461 
    462 	if (_cursesi_screen->notty == TRUE)
    463 		return OK;
    464 	_cursesi_screen->rawt.c_iflag |= ICRNL;
    465 	_cursesi_screen->rawt.c_oflag |= ONLCR;
    466 	_cursesi_screen->cbreakt.c_iflag |= ICRNL;
    467 	_cursesi_screen->cbreakt.c_oflag |= ONLCR;
    468 	_cursesi_screen->baset.c_iflag |= ICRNL;
    469 	_cursesi_screen->baset.c_oflag |= ONLCR;
    470 
    471 	_cursesi_screen->nl = 1;
    472 	_cursesi_screen->pfast = _cursesi_screen->rawmode;
    473 	return tcsetattr(fileno(_cursesi_screen->infd), TCSASOFT | TCSADRAIN,
    474 	    _cursesi_screen->curt) ? ERR : OK;
    475 }
    476 
    477 int
    478 nonl(void)
    479 {
    480 #ifdef DEBUG
    481 	__CTRACE(__CTRACE_MISC, "nonl()\n");
    482 #endif
    483 	/* Check if we need to restart ... */
    484 	if (_cursesi_screen->endwin)
    485 		__restartwin();
    486 
    487 	if (_cursesi_screen->notty == TRUE)
    488 		return OK;
    489 	_cursesi_screen->rawt.c_iflag &= ~ICRNL;
    490 	_cursesi_screen->rawt.c_oflag &= ~ONLCR;
    491 	_cursesi_screen->cbreakt.c_iflag &= ~ICRNL;
    492 	_cursesi_screen->cbreakt.c_oflag &= ~ONLCR;
    493 	_cursesi_screen->baset.c_iflag &= ~ICRNL;
    494 	_cursesi_screen->baset.c_oflag &= ~ONLCR;
    495 
    496 	_cursesi_screen->nl = 0;
    497 	__pfast = 1;
    498 	return tcsetattr(fileno(_cursesi_screen->infd), TCSASOFT | TCSADRAIN,
    499 	    _cursesi_screen->curt) ? ERR : OK;
    500 }
    501 
    502 #ifndef _CURSES_USE_MACROS
    503 void
    504 noqiflush(void)
    505 {
    506 
    507 	(void)intrflush(stdscr, FALSE);
    508 }
    509 
    510 void
    511 qiflush(void)
    512 {
    513 
    514 	(void)intrflush(stdscr, TRUE);
    515 }
    516 #endif	/* _CURSES_USE_MACROS */
    517 
    518 /*ARGSUSED*/
    519 int
    520 intrflush(WINDOW *win, bool bf)
    521 {
    522 	/* Check if we need to restart ... */
    523 	if (_cursesi_screen->endwin)
    524 		__restartwin();
    525 
    526 	if (_cursesi_screen->notty == TRUE)
    527 		return OK;
    528 	if (bf) {
    529 		_cursesi_screen->rawt.c_lflag &= ~NOFLSH;
    530 		_cursesi_screen->cbreakt.c_lflag &= ~NOFLSH;
    531 		_cursesi_screen->baset.c_lflag &= ~NOFLSH;
    532 	} else {
    533 		_cursesi_screen->rawt.c_lflag |= NOFLSH;
    534 		_cursesi_screen->cbreakt.c_lflag |= NOFLSH;
    535 		_cursesi_screen->baset.c_lflag |= NOFLSH;
    536 	}
    537 
    538 	__pfast = 1;
    539 	return tcsetattr(fileno(_cursesi_screen->infd), TCSASOFT | TCSADRAIN,
    540 	    _cursesi_screen->curt) ? ERR : OK;
    541 }
    542 
    543 void
    544 __startwin(SCREEN *screen)
    545 {
    546 
    547 	(void)fflush(screen->infd);
    548 
    549 #ifdef BSD
    550 	/*
    551 	 * Some C libraries default to a 1K buffer when talking to a tty.
    552 	 * With a larger screen, especially across a network, we'd like
    553 	 * to get it to all flush in a single write.  Make it twice as big
    554 	 * as just the characters (so that we have room for cursor motions
    555 	 * and attribute information) but no more than 8K.
    556 	 *
    557 	 * However, setvbuf may only be used after opening a stream and
    558 	 * before any operations have been performed on it.
    559 	 * This means we cannot work portably if an application wants
    560 	 * to stop curses and start curses after a resize.
    561 	 * Curses resizing is not standard, and thus not strictly portable
    562 	 * even though all curses today support it.
    563 	 * The BSD systems do not suffer from this limitation on setvbuf.
    564 	 */
    565 	if (screen->stdbuf == NULL) {
    566 		screen->len = LINES * COLS * 2;
    567 		if (screen->len > 8192)
    568 			screen->len = 8192;
    569 		if ((screen->stdbuf = malloc(screen->len)) == NULL)
    570 			screen->len = 0;
    571 	}
    572 	(void)setvbuf(screen->outfd, screen->stdbuf, _IOFBF, screen->len);
    573 #endif
    574 
    575 	ti_puts(screen->term, t_enter_ca_mode(screen->term), 0,
    576 		__cputchar_args, (void *) screen->outfd);
    577 	ti_puts(screen->term, t_cursor_normal(screen->term), 0,
    578 	    __cputchar_args, (void *) screen->outfd);
    579 	if (screen->curscr->flags & __KEYPAD)
    580 		ti_puts(screen->term, t_keypad_xmit(screen->term), 0,
    581 		    __cputchar_args, (void *) screen->outfd);
    582 	screen->endwin = 0;
    583 }
    584 
    585 int
    586 endwin(void)
    587 {
    588 #ifdef DEBUG
    589 	__CTRACE(__CTRACE_MISC, "endwin\n");
    590 #endif
    591 	return __stopwin();
    592 }
    593 
    594 bool
    595 isendwin(void)
    596 {
    597 
    598 	return _cursesi_screen->endwin ? TRUE : FALSE;
    599 }
    600 
    601 int
    602 flushinp(void)
    603 {
    604 
    605 	(void)fpurge(_cursesi_screen->infd);
    606 	return OK;
    607 }
    608 
    609 /*
    610  * The following routines, savetty and resetty are completely useless and
    611  * are left in only as stubs.  If people actually use them they will almost
    612  * certainly screw up the state of the world.
    613  */
    614 /*static struct termios savedtty;*/
    615 int
    616 savetty(void)
    617 {
    618 
    619 	if (_cursesi_screen->notty == TRUE)
    620 		return OK;
    621 	return tcgetattr(fileno(_cursesi_screen->infd),
    622 			 &_cursesi_screen->savedtty) ? ERR : OK;
    623 }
    624 
    625 int
    626 resetty(void)
    627 {
    628 
    629 	if (_cursesi_screen->notty == TRUE)
    630 		return OK;
    631 	return tcsetattr(fileno(_cursesi_screen->infd), TCSASOFT | TCSADRAIN,
    632 			 &_cursesi_screen->savedtty) ? ERR : OK;
    633 }
    634 
    635 /*
    636  * erasechar --
    637  *     Return the character of the erase key.
    638  */
    639 char
    640 erasechar(void)
    641 {
    642 
    643 	if (_cursesi_screen->notty == TRUE)
    644 		return 0;
    645 	return _cursesi_screen->baset.c_cc[VERASE];
    646 }
    647 
    648 /*
    649  * killchar --
    650  *     Return the character of the kill key.
    651  */
    652 char
    653 killchar(void)
    654 {
    655 
    656 	if (_cursesi_screen->notty == TRUE)
    657 		return 0;
    658 	return _cursesi_screen->baset.c_cc[VKILL];
    659 }
    660 
    661 /*
    662  * erasewchar --
    663  *     Return the wide character of the erase key.
    664  */
    665 int
    666 erasewchar(wchar_t *ch)
    667 {
    668 
    669 #ifndef HAVE_WCHAR
    670 	return ERR;
    671 #else
    672 	if (_cursesi_screen->notty == TRUE)
    673 		return ERR;
    674 	*ch = _cursesi_screen->baset.c_cc[VERASE];
    675 	return OK;
    676 #endif /* HAVE_WCHAR */
    677 }
    678 
    679 /*
    680  * killwchar --
    681  *     Return the wide character of the kill key.
    682  */
    683 int
    684 killwchar( wchar_t *ch )
    685 {
    686 
    687 #ifndef HAVE_WCHAR
    688 	return ERR;
    689 #else
    690 	if (_cursesi_screen->notty == TRUE)
    691 		return 0;
    692 	*ch = _cursesi_screen->baset.c_cc[VKILL];
    693 	return OK;
    694 #endif /* HAVE_WCHAR */
    695 }
    696 
    697 int
    698 typeahead(int filedes)
    699 {
    700 
    701 	_cursesi_screen->checkfd = filedes;
    702 	return OK;
    703 }
    704