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ttyin.c revision 1.2 
      1 /*	$NetBSD: ttyin.c,v 1.2 1998/01/09 08:03:38 perry Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1988 Mark Nudleman
      5  * Copyright (c) 1988, 1993
      6  *	The Regents of the University of California.  All rights reserved.
      7  *
      8  * Redistribution and use in source and binary forms, with or without
      9  * modification, are permitted provided that the following conditions
     10  * are met:
     11  * 1. Redistributions of source code must retain the above copyright
     12  *    notice, this list of conditions and the following disclaimer.
     13  * 2. Redistributions in binary form must reproduce the above copyright
     14  *    notice, this list of conditions and the following disclaimer in the
     15  *    documentation and/or other materials provided with the distribution.
     16  * 3. All advertising materials mentioning features or use of this software
     17  *    must display the following acknowledgement:
     18  *	This product includes software developed by the University of
     19  *	California, Berkeley and its contributors.
     20  * 4. Neither the name of the University nor the names of its contributors
     21  *    may be used to endorse or promote products derived from this software
     22  *    without specific prior written permission.
     23  *
     24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     34  * SUCH DAMAGE.
     35  */
     36 
     37 #ifndef lint
     38 static char sccsid[] = "@(#)ttyin.c	8.1 (Berkeley) 6/6/93";
     39 #endif /* not lint */
     40 
     41 /*
     42  * Routines dealing with getting input from the keyboard (i.e. from the user).
     43  */
     44 
     45 #include <less.h>
     46 
     47 static int tty;
     48 
     49 /*
     50  * Open keyboard for input.
     51  * (Just use file descriptor 2.)
     52  */
     53 open_getchr()
     54 {
     55 	tty = 2;
     56 }
     57 
     58 /*
     59  * Get a character from the keyboard.
     60  */
     61 getchr()
     62 {
     63 	char c;
     64 	int result;
     65 
     66 	do
     67 	{
     68 		result = iread(tty, &c, 1);
     69 		if (result == READ_INTR)
     70 			return (READ_INTR);
     71 		if (result < 0)
     72 		{
     73 			/*
     74 			 * Don't call error() here,
     75 			 * because error calls getchr!
     76 			 */
     77 			quit();
     78 		}
     79 	} while (result != 1);
     80 	return (c & 0177);
     81 }
     82