echo.c revision 1.8 
1/*	$NetBSD: echo.c,v 1.8 1996/11/02 18:26:06 christos Exp $	*/
2
3/*-
4 * Copyright (c) 1991, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Kenneth Almquist.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 *    must display the following acknowledgement:
20 *	This product includes software developed by the University of
21 *	California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 *    may be used to endorse or promote products derived from this software
24 *    without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 *
38 *	@(#)echo.c	8.1 (Berkeley) 5/31/93
39 */
40
41/*
42 * Echo command.
43 */
44
45#define main echocmd
46
47#include "bltin.h"
48
49/* #define eflag 1 */
50
51int
52main(argc, argv)  char **argv; {
53	register char **ap;
54	register char *p;
55	register char c;
56	int count;
57	int nflag = 0;
58#ifndef eflag
59	int eflag = 0;
60#endif
61
62	ap = argv;
63	if (argc)
64		ap++;
65	if ((p = *ap) != NULL) {
66		if (equal(p, "-n")) {
67			nflag++;
68			ap++;
69		} else if (equal(p, "-e")) {
70#ifndef eflag
71			eflag++;
72#endif
73			ap++;
74		}
75	}
76	while ((p = *ap++) != NULL) {
77		while ((c = *p++) != '\0') {
78			if (c == '\\' && eflag) {
79				switch (*p++) {
80				case 'b':  c = '\b';  break;
81				case 'c':  return 0;		/* exit */
82				case 'f':  c = '\f';  break;
83				case 'n':  c = '\n';  break;
84				case 'r':  c = '\r';  break;
85				case 't':  c = '\t';  break;
86				case 'v':  c = '\v';  break;
87				case '\\':  break;		/* c = '\\' */
88				case '0':
89					c = 0;
90					count = 3;
91					while (--count >= 0 && (unsigned)(*p - '0') < 8)
92						c = (c << 3) + (*p++ - '0');
93					break;
94				default:
95					p--;
96					break;
97				}
98			}
99			putchar(c);
100		}
101		if (*ap)
102			putchar(' ');
103	}
104	if (! nflag)
105		putchar('\n');
106	return 0;
107}
108