rev.c revision 1.9 
1/*	$NetBSD: rev.c,v 1.9 2009/04/13 04:36:34 lukem Exp $	*/
2
3/*-
4 * Copyright (c) 1987, 1992, 1993
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__COPYRIGHT("@(#) Copyright (c) 1987, 1992, 1993\
35 The Regents of the University of California.  All rights reserved.");
36#endif /* not lint */
37
38#ifndef lint
39#if 0
40static char sccsid[] = "@(#)rev.c	8.3 (Berkeley) 5/4/95";
41#else
42__RCSID("$NetBSD: rev.c,v 1.9 2009/04/13 04:36:34 lukem Exp $");
43#endif
44#endif /* not lint */
45
46#include <sys/types.h>
47
48#include <err.h>
49#include <errno.h>
50#include <stdio.h>
51#include <stdlib.h>
52#include <string.h>
53#include <unistd.h>
54
55int	main __P((int, char **));
56void	usage __P((void));
57
58int
59main(argc, argv)
60	int argc;
61	char *argv[];
62{
63	const char *filename;
64	char *p, *t;
65	FILE *fp;
66	size_t len;
67	int ch, rval;
68
69	while ((ch = getopt(argc, argv, "")) != -1)
70		switch(ch) {
71		case '?':
72		default:
73			usage();
74		}
75
76	argc -= optind;
77	argv += optind;
78
79	fp = stdin;
80	filename = "stdin";
81	rval = 0;
82	do {
83		if (*argv) {
84			if ((fp = fopen(*argv, "r")) == NULL) {
85				warn("%s", *argv);
86				rval = 1;
87				++argv;
88				continue;
89			}
90			filename = *argv++;
91		}
92		while ((p = fgetln(fp, &len)) != NULL) {
93			if (p[len - 1] == '\n')
94				--len;
95			t = p + len - 1;
96			for (t = p + len - 1; t >= p; --t)
97				putchar(*t);
98			putchar('\n');
99		}
100		if (ferror(fp)) {
101			warn("%s", filename);
102			rval = 1;
103		}
104		(void)fclose(fp);
105	} while(*argv);
106	exit(rval);
107}
108
109void
110usage()
111{
112	(void)fprintf(stderr, "usage: rev [file ...]\n");
113	exit(1);
114}
115