rev.c revision 1.7 
1/*	$NetBSD: rev.c,v 1.7 2003/08/07 11:15:39 agc 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\n\
35	The Regents of the University of California.  All rights reserved.\n");
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 1.7 2003/08/07 11:15:39 agc 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	char *filename, *p, *t;
64	FILE *fp;
65	size_t len;
66	int ch, rval;
67
68	while ((ch = getopt(argc, argv, "")) != -1)
69		switch(ch) {
70		case '?':
71		default:
72			usage();
73		}
74
75	argc -= optind;
76	argv += optind;
77
78	fp = stdin;
79	filename = "stdin";
80	rval = 0;
81	do {
82		if (*argv) {
83			if ((fp = fopen(*argv, "r")) == NULL) {
84				warn("%s", *argv);
85				rval = 1;
86				++argv;
87				continue;
88			}
89			filename = *argv++;
90		}
91		while ((p = fgetln(fp, &len)) != NULL) {
92			if (p[len - 1] == '\n')
93				--len;
94			t = p + len - 1;
95			for (t = p + len - 1; t >= p; --t)
96				putchar(*t);
97			putchar('\n');
98		}
99		if (ferror(fp)) {
100			warn("%s", filename);
101			rval = 1;
102		}
103		(void)fclose(fp);
104	} while(*argv);
105	exit(rval);
106}
107
108void
109usage()
110{
111	(void)fprintf(stderr, "usage: rev [file ...]\n");
112	exit(1);
113}
114