1 /* $NetBSD: ttyin.c,v 1.3 1998/02/04 11:09:13 christos 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 #include <sys/cdefs.h> 38 #ifndef lint 39 #if 0 40 static char sccsid[] = "@(#)ttyin.c 8.1 (Berkeley) 6/6/93"; 41 #else 42 __RCSID("$NetBSD: ttyin.c,v 1.3 1998/02/04 11:09:13 christos Exp $"); 43 #endif 44 #endif /* not lint */ 45 46 /* 47 * Routines dealing with getting input from the keyboard (i.e. from the user). 48 */ 49 50 #include <sys/types.h> 51 52 #include "less.h" 53 #include "extern.h" 54 55 static int tty; 56 57 /* 58 * Open keyboard for input. 59 * (Just use file descriptor 2.) 60 */ 61 void 62 open_getchr() 63 { 64 tty = 2; 65 } 66 67 /* 68 * Get a character from the keyboard. 69 */ 70 int 71 getchr() 72 { 73 char c; 74 int result; 75 76 do 77 { 78 result = iread(tty, &c, 1); 79 if (result == READ_INTR) 80 return (READ_INTR); 81 if (result < 0) 82 { 83 /* 84 * Don't call error() here, 85 * because error calls getchr! 86 */ 87 quit(); 88 } 89 } while (result != 1); 90 return (c & 0177); 91 } 92